BRIEF REPORT | doi:10.20944/preprints202306.0463.v2
Subject: Biology And Life Sciences, Plant Sciences Keywords: Chloroplast genome; Passifloraceae; Passiflora tripartita; poro-poro; Huánuco; Peru
Online: 7 June 2023 (12:23:59 CEST)
Poro-poro is an important native fruit used in traditional Peruvian medicine with relevant agro-industrial and pharmaceutical potential for its antioxidant capacity for human health. However, to date, there have been few genetic studies. The lack of genomic exploration limits the possibility of expanding our knowledge of its molecular evolution, new molecular pathways, genetic traits, and evolutionary relationships. Here, we report the plastid genome sequence of Passiflora tripartita var. mollissima and the reconstructed phylogenetic tree to infer the phylogenetic relationships among Passiflora species. Our phylogenetic analysis showed that poro-poro is most closely related to Passiflora menispermifolia and Passiflora oerstedii. In summary, our study provides the basis for developing new molecular markers that constitutes a valuable resource for studying molecular evolution and domestication. It also provides a powerful foundation for conservation genetics research and plant breeding programs. To our knowledge, this is the first report on the plastid genome of Passiflora tripartita var. mollissima from Peru.
ARTICLE | doi:10.20944/preprints202306.0444.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Climate change; Net photosynthetic rate; Chalky grain; Growth; High temperature
Online: 6 June 2023 (11:07:59 CEST)
Global warming causes an alarming increase in temperature which negatively affects growth, physiology, and yield of rice. To gain some insights into the impacts of booting HT (at 42°C, 3 h for 7 days), we investigated its effect in three rice genotypes, namely, N22, KDML105 and IR64. Booting HT caused an extended phenology and lower photosynthesis and plant growth rate but an increase in chalkiness. Although, prolonged phenology from dough to physiological maturity led to longer duration of grain filling, the negative effects of its was significantly lower yield components, yield and harvest index in all rice. Among cultivars, N22 presented adapted ability to maintain leaf gas exchange and compensated vegetative part by an increase in tiller numbers resulting in less affected growth rate. It prolonged phenology that caused extended grain filling. Consequence, N22 was the lowest reduction in number of seed panicle–1, number of filled seeds hill–1, yield, HI as well as the lowest percentage chalkiness. KDML105 adapted to booting HT by maintaining leaf gas exchange, increasing specific leaf area and prolonging phenology. The longest extended phenology together with the maintenance of high photosynthesis during dough grain were associated with moderate yield reduction and chalkiness. However, IR64 showed dramatic reductions in photosynthesis, growth rate, and yield but highest percentage grain chalkiness. Therefore, in response to booting HT, N22, KDML105 and IR64 could be indicated as being heat tolerant, moderately heat sensitive, and heat sensitive, respectively. This can be applied for crop modelling and rice heat tolerance in breeding program.
ARTICLE | doi:10.20944/preprints202306.0437.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Azospirillum brasilense; biological nitrogen fixation; microbial auxin biosynthesis; ATP biosynthesis; micronutrient uptake; light stimulation
Online: 6 June 2023 (10:01:34 CEST)
As the use of microbial inoculants in agriculture rises, it becomes important to understand how the environment may influence microbial ability to promote plant growth. This work examines whether there are light dependencies in the biological functions of Azospirillum brasilense, a commercialized prolific grass-root colonizer. Though classically defined as non-phototrophic, A. brasilense possesses photoreceptors that could perceive light conducted through its host’s roots. Evidence for light dependency of four microbial processes were examined and noted: biological nitrogen fixation (BNF), auxin biosynthesis, ATP biosynthesis, and iron and manganese uptake. Functional mutants of A. brasilense were leveraged and studied in light and dark environments: HM053 (high BNF and auxin production), ipdC (capable of BNF, deficient in auxin production), and FP10 (capable of auxin production, deficient in BNF). HM053 exhibited the highest rate of nitrogenase activity with the greatest light dependency comparing iterations in light and dark environments. The ipdC mutant showed similar behavior with relatively lower nitrogenase activity observed, while FP10 did not show a light dependency. Auxin biosynthesis showed strong light dependencies in HM053 and FP10 strains, but not for ipdC. Iron is involved in the BNF biological process, and light dependency was observed for microbial 59Fe2+ uptake in HM053 and ipdC, but not FP10. Surprisingly, a light dependency for 52Mn2+ uptake was only observed in ipdC. Finally, ATP biosynthesis was sensitive to light across all three mutants favoring blue light over red light compared to darkness with observed ATP levels in descending order for HM053 > ipdC > FP10.
ARTICLE | doi:10.20944/preprints202306.0225.v2
Subject: Biology And Life Sciences, Plant Sciences Keywords: Auxin; cell wall composition; chlorogenic acid; lignin; pectin; post harvest wounding; tap roots
Online: 6 June 2023 (03:57:18 CEST)
The blackening of cut carrots decreases their shelf life and causes severe economic losses but the molecular and metabolic mechanisms that underpin this phenomenon remain poorly characterized. Studies were therefore undertaken to determine the molecular and metabolic causes of the blackening. The susceptibility of blackening was dependent on the period of time that the crop was stored underground prior to harvest. The structure of the cell walls in the black regions was substantially changed compared to the orange regions. The black regions of carrot batons had decreased immunodetection of xyloglucan, HG-pectin, RG-I pectin, galactan and arabinan but had higher levels of lignin and phenolic compounds compared to the orange regions. Transcript profiling analysis revealed that phytohormone signalling processes were activated in the black regions. Transcripts associated with auxin signalling and ethylene-responsive transcription factors were increased in the black regions. In contrast, the levels of transcripts encoding proteins associated with secondary metabolism were decreased in the black regions. These findings implicate ethylene and auxin-related processes in the control of the primary to secondary metabolism shift that results in lignification and cell wall disruption that underpin the blackening process.
ARTICLE | doi:10.20944/preprints202306.0366.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Liquid liquid phase separation; protein oligomerization; GO; domain-domain interaction; domain linker; intrinsically disordered regions; domain-peptide interaction; beta-sheet; transmembrane helices; post-translational modification
Online: 6 June 2023 (03:43:57 CEST)
Although there are a large number of databases available for regulatory elements, bottleneck has been created by the lack of bioinformatics tools for predicting types of mechanisms underlying actions of regulatory elements. To reduce the gap, we developed ARabidopsis Transcription regulatory Factor Domain-domain interaction Analysis Tool- Liquid-liquid phase separation (LLPS), Oligomerization, GO analysis (ART FounDATion-LOG), a useful toolkit for protein-nucleic acid interactions (PNI) and protein-protein interactions (PPI) analysis based on domain-domain interaction (DDI). LLPS, protein oligomerization, structural properties of protein domains, and protein modifications are major components in orchestrating spatio-temporal dynamics of PPI and PNI. Our goal is to integrate PPI/PNI information into development of prediction model for identifying important genetic variants in peach. The program unified inter-database relational keys by protein domains for facilitating inference from the model species. Key advantage of the program lies in the integrated information of related features: LOG, structural characterization of domain (e.g. domain linker, intrinsically disordered regions, DDI, domain-motif (peptide) interaction, beta-sheet and transmembrane helices), and post-translational modification. We provided simple tests to demonstrate how to use the program. The program may be applied to other eukaryotic organisms. The program codes and data are freely available for download at and https://sourceforge.net/projects/artfoundation-log/.
ARTICLE | doi:10.20944/preprints202306.0349.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Alkaloids; Cells; Cranichideae; Ergastic substances; Leaf; Micromorphology; Orchidoideae; Rhizomes; Roots; Spiranthinae
Online: 5 June 2023 (16:19:40 CEST)
The orchid genus Brachystele Schltr. comprises 20 species distributed from Mexico to Argentina; 10 are found in Brazil. Anatomical studies of Orchidoideae Lindl. have been scarce, and the anatomy and histochemistry of Brachystele are still largely unknown. We characterized the vegetative organs of B. guayanensis (Lindl.) Schltr. using standard anatomical and histochemical microtechniques. Brachystele guayanensis was observed to display the anatomical characters commonly found in the vegetative organs of representatives of the Orchidaceae and Orchidoideae (including a uniseriate epidermis, thin cuticle, amphistomatic leaves, anomocytic, diacytic and tetracytic stomata, a homogeneous mesophyll, collateral vascular bundles, rhizomes with pericyclic fibers, roots with velamen, uniseriate exodermis, endodermis and pericycle). Histochemical tests confirmed the presence of lignin, proteins, and alkaloids, the lipidic nature of the cuticle, starch grains stored in spiranthosomes in the roots, and the composition of the raphides. Alkaloids were observed in great abundance, especially in the roots, and may have potentially useful medicinal activities, as has been observed in groups phylogenetically related to Brachystele.
ARTICLE | doi:10.20944/preprints202306.0347.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: soil amendment; Fenton reaction; seedling growth; plant proteomics; Lettuce
Online: 5 June 2023 (16:14:19 CEST)
Information regarding physiological and molecular plant responses to the treatment with new biofertilizers is limited. In this study a fast-composting soil amendment (FCA), obtained from solid waste by means of a Fenton reaction, was tested to evaluate the effects on the growth of Lactuca sativa L. var. longifolia seedlings. Growth rate, leaves and roots biomass, chlorophyll concentration and total soluble proteins of seedlings treated with the 2% FCA soil amendment showed significant increase in comparison with control seedlings. Leaf proteomic analysis revealed that the FCA soil amendment induced the up-regulation of proteins belonging to photosynthesis machinery, carbohydrate metabolism and promoted the up-regulation of the water stress response. Root proteomics indicated that FCA strongly induced the organs morphogenesis and developments; root cap development, lateral root formation, post-embryonic root morphogenesis were the main biological processes enriched by the treatment. Overall, our data suggest that addition of FCA formulation to the base soils might ameliorate plant growth by inducing carbohydrates primary metabolism and the differentiation of a robust root system.
ARTICLE | doi:10.20944/preprints202306.0183.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: allelopathy; barnyardgrass; root trait; phytohormone; biotic stress
Online: 2 June 2023 (10:29:48 CEST)
Barnyardgrass (Echinochloa spp.) is a prevalent type of weed in rice fields worldwide. Despite the growing knowledge concerning allelopathic interference with barnyardgrass, little is understood regarding the competitive mechanisms between allelopathic rice and herbicide-resistant barnyardgrass at the plant physiological level. In this context, a hydroponic system was employed to investigate the root morphological traits and different phytohormones levels of two rice cultivars, i.e., the allelopathic rice cultivar “PI312777” (PI) and the non-allelopathic rice cultivar “Lemont” (LE), when co-planted with quinclorac-resistant and -susceptible barnyardgrass, respectively. The results showed that the shoot and root biomass were greater in the allelopathic rice cultivar. Moreover, the treatments at the two time points induced an increase in shoot and root biomass of PI when subjected to barnyardgrass stress. In terms of root morphology, PI exhibited significantly higher fine-root length in diameters <0.5 mm, a greater number of root tips, and longer root tips compared to LE. In addition, the levels of different plant hormones, including auxin (IAA), abscisic acid (ABA), jasmonic acid (JA), and salicylic acid (SA), known for their diverse adaptation strategies to biotic stress, were analysed. The response to quinclorac-resistant barnyardgrass stress was consistent in terms of the content of well-known stress-related hormones, namely SA and JA. The accumulation of SA and JA was observed in both rice cultivars under the stress of quinclorac-resistant barnyardgrass, with higher contents of these hormones in PI than that in LE. The most significant change was observed in IAA and ABA contents in rice, which decreased significantly from 7 days to 14 days under co-culture stress. Additionally, PI contained higher levels of IAA and ABA than LE in the presence of barnyardgrass stress. This research may aid in the development of strategies for reducing the environmental impact of herbicides through the prudent selection of non-chemical herbicide control tactics.
ARTICLE | doi:10.20944/preprints202305.2192.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Bread wheat; climate-smart germplasm; adaptation; global warming; heat tolerance; yield stability
Online: 31 May 2023 (07:53:47 CEST)
Bread wheat (Triticum aestivum L.) is one of the world's most important staple food crop providing 20% global energy and dietary proteins. It is widely grown in sub-tropical and tropical areas and as such exposed to heat-stress especially at grain filling period (GFP). Global warming has further affected its production and productivity in these heat-stressed environments. We examined the effect of heat-stress on 18 morpho-physiological and yield-related traits in 96 bread wheat accessions. Heat susceptibility index (HSI <0.60) and yield stability (i <0.55) used as criteria for selecting the tolerant accessions. Heat-stress, imposed by delayed sowing, decreased crop growth and GFP, and as a result reduced morphological and yield-related traits, namely days to 50% anthesis, plant height, peduncle length, flag-leaf area, spike length, spikelets per spike, grain length and width, thousand grain weight (TGW), harvest index and yield. The reduction in the trait values was severe in susceptible accessions (48.2% yield reduction in IC277741) than the tolerant. Physiological traits like chlorophyll content, canopy temperature depression (CTD), normalized difference vegetation index (NDVI), plant waxiness and leaf rolling showed higher expression in the tolerant accessions under heat-stress. Scanning electron microscopy of matured wheat grains revealed ultrastructural changes in endosperm and aleurone cells caused due to heat-stress. The reduction of size and density of large starch granules is the major cause of yield and TGW decrease in the heat-stress susceptible lines. The most stable and high-yielding accessions namely IC566223, IC128454, IC335792, EC576707, IC535176, IC529207, IC446713 and IC416019 were identified as the climate-smart germplasm lines. Germplasm lines possessing desirable traits were selected as po-tential parents for the development of bi-parental and multi-parental populations.
REVIEW | doi:10.20944/preprints202305.2182.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Banana; Somatic embryogenesis; Embryogenic cell suspension; Morphogenic genes
Online: 31 May 2023 (07:33:09 CEST)
Bananas and plantains (Musa spp.) cultivation holds significant global economic importance, but it faces numerous challenges, which may include diverse abiotic and biotic factors such as drought and various diseases caused by fungi, viruses, and bacteria. The genetic and asexual nature of cultivated banana varieties makes them unattractive for improvement via traditional breeding. To overcome these constraints, modern biotechnological approaches like genetic modification and genome editing have become essential for banana improvement. However, these techniques rely on somatic embryogenesis, which has only been successfully achieved in a limited number of banana cultivars. Therefore, developing new strategies for improving somatic embryogenesis in banana is crucial. This review article focuses on advancements in banana somatic embryogenesis, highlighting the progress, the various stages involved, cryopreservation techniques, and the molecular mechanisms underlying the process. Furthermore, the article discusses the factors that could influence somatic embryogenesis and explores the prospects for improving the process, especially in recalcitrant banana cultivars. By addressing these challenges and exploring potential solutions, researchers aim to unlock the full potential of somatic embryogenesis as a tool for banana improvement, ultimately benefiting the global banana industry.
REVIEW | doi:10.20944/preprints202305.2065.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Green Tea Catechins (ECGC); andrographolide; curcumin; Skin photoprotection; Skin permeation; Oxidative stress; Antimicrobial; Cosmetic and dermatologic formulations
Online: 30 May 2023 (07:27:36 CEST)
Here we have chosen to highlight the main natural molecules extracted from camellia sinensis, andrographis paniculata and curcuma longa that may possess antioxidant activities of interest for skin protection. The molecules involved, in the antioxidant process are respectively catechins derivatives, in particular EGCG, andrographolide and its derivatives as well as various curcuminoids. These plants are generally used as beverages for camellia sinensis (tea tree), as dietary supplements or as spices. The molecules they contain are known for their diverse therapeutic activities, including anti-inflammatory, antimicrobial, anti-cancer, antidiabetic and dermatological treatment. Their common antioxidant activities and therapeutic applications are widely documented, but their use in cosmetic is more recent. In this review, we will endeavor to compile the cosmetic uses of these natural molecules of interest, the various structural modulations reported, with the aim of improving their bioavailability as well as establishing their different mechanisms of action.
ARTICLE | doi:10.20944/preprints202305.1960.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: C. dactylon; C. transvaalensis; interspecific hybrids; cluster analysis; genetic similarity; genetic diversity; directional breeding
Online: 29 May 2023 (08:55:06 CEST)
Bermudagrass (Cynodon spp.) is one of the drought-resistant warm-season turfgrasses adapted to the southern and transitional zones in the United States. Multiple hybrid varieties have been developed and released for use as a turfgrass and others are in pipeline. Increasing genetic di-versity of commercial varieties is vital to tackle stress tolerance. A DNA profiling study of 21 experimental selections from the Oklahoma State University (OSU) turfgrass breeding program and 11 cultivars was conducted using 51 simple sequence repeat (SSR) primer pairs that spread across the bermudagrass genome. Pairwise genetic relationship analysis among the genotypes using 352 polymorphic bands showed genetic similarity coefficients ranging from 0.59 to 0.89. Cluster analysis using the un-weighted paired group method with arithmetic average (UPGMA) method grouped the entries into six clusters. Correlation analysis identified different levels of pairwise genetic relationship among the entries that largely reflected parental relationship. Di-rectional breeding and selection for cold hardiness or drought resistance created progeny that had distinct genetic diversity in the tested bermudagrasses. It is evident that an increase in genetic diversity of the existing cultivar pool with the release of one or more of the experimental selec-tions for commercial use will strengthen and improve bermudagrass systems.
ARTICLE | doi:10.20944/preprints202305.1946.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: RACK1B; Rice; Salt stress; Stay-green; Light Harvesting Complex; Chlorophyll degradation; Senescence
Online: 29 May 2023 (02:26:49 CEST)
Abstract: The widely conserved RACK1 protein is a WD-40 type scaffold protein that regulates diverse environmental stress signal transduction pathways. Arabidopsis RACK1A has been reported to interact with various proteins in salt stress and Light-Harvesting Complex (LHC) pathways. However, the mechanism of how RACK1 contributes to the photosystem and chlorophyll metabolism in stress conditions remains elusive. Using T-DNA-mediated activation tagging transgenic rice (Oryza sativa L.) lines, we show that leaves from rice RACK1B gene (OsRACK1B) gain-of-function (RACK1B-OX) plants exhibit the stay-green phenotype under salinity stress. In contrast, leaves from down-regulated OsRACK1B (RACK1B-UX) plants display an accelerated yellowing. qRT-PCR analysis revealed that several genes encoding chlorophyll catabolic enzymes (CCEs) are differentially expressed in both RACK1B-OX and RACK1B-UX rice plants. In addition to CCEs, STAY-GREEN (SGR) is a key component that forms the SGR-CCE complex in senescing chloroplasts, which causes LHCII complex instability. Transcript and protein profiling revealed a significant upregulation of OsSGR in RACK1B-UX plants than that in RACK1B-OX rice plants during salt treatment. The results imply that senescence-associated transcription factors (TFs) are altered in accordance with altered OsRACK1B expression, indicating a transcriptional reprogramming by OsRACK1B and a novel regulatory mechanism involving the OsRACK1B-OsSGR-TFs complex. Our findings suggest that ectopic expression of OsRACK1B negatively regulates chlorophyll degradation, leads to the steady level of LHC-II isoform Lhcb1, an essential prerequisite for the state transition of photosynthesis for adaptation, and delays salinity-induced senescence. Taken together, these results provide important insights into the molecular mechanisms of salinity-induced senescence, which can be useful in circumventing the effect of salt on photosynthesis and in reducing the yield penalty of important cereal crops, like rice, in global climate change conditions.
REVIEW | doi:10.20944/preprints202305.1919.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Orchids; microorganisms; fungi; bacteria
Online: 26 May 2023 (10:37:30 CEST)
Orchids are often a mystery because of their close and complex relationships with various microorganisms in the natural environment. Orchids rely on microorganisms to obtain nutrients, affecting their seed germination, protocorm, and adult plant growth. Currently, the majority of relevant research is concentrated on isolating and identifying environmental microorganisms that support orchid development and growth. With the development of metagenomic technology, our understanding of orchid mycorrhizal fungi (OMF) and root-associated bacteria (RAB) has been expanded. New research results and discoveries have emerged, which require a comprehensive assessment to provide a reference for studying microorganisms related to orchids. Therefore, we present a comprehensive summary, identifying significant inadequacies of present methodologies while providing ideas for further research.
ARTICLE | doi:10.20944/preprints202305.1897.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: GmCAMTA; circadian rhythm; development; drought stress
Online: 26 May 2023 (09:14:59 CEST)
The calmodulin-binding transcription activators (CAMTAs) mediate transcriptional regulation of development, growth, and responses to various environmental stresses in plants. To characterize the biological processes of soybean CAMTA (GmCAMTA) family members in response to abiotic stress, we identified 15 GmCAMTA genes from soybean (Glycine max L.) and investigated their roles in the abiotic stress response. The transcriptions of GmCAMTAs exhibited distinct circadian regulation patterns and were expressed differently in response to salt, drought, and cold stresses, except ABA. Interestingly, the expression levels of GmCAMTA2, GmCAMTA8, and GmCAMTA12 were higher in stem tissue than in other soybean tissues. To determine the roles of GmCAMTAs in the regulation of developmental processes and stress responses, we isolated GmCAMTA2 and GmCAMTA8 cDNAs from soybean and generated Arabidopsis overexpressing transgenic plants. The GmCAMTA2-OX and GmCAMTA8-OX plants showed hypersensitivity to drought stress. The water in the leaves of GmCAMTA2-OX and GmCAMTA8-OX plants was lost faster than that in WT plants under drought stress conditions. In addition, stress-responsive genes in the GmCAMTA2-OX and GmCAMTA8-OX plants were down-regulated under drought stress conditions. Our results suggest that GmCAMTA2 and GmCAMTA8 genes are regulated by circadian rhythms and function as negative regulators in development and drought stress responses.
ARTICLE | doi:10.20944/preprints202305.1861.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: grain yield; biomass; N application rate; high-quality rice
Online: 26 May 2023 (05:23:37 CEST)
High-quality rice (Oryza sativa L.) is increasingly widely planted in China with the improvement of people's living standards and the achievement of rice breeding efforts in recent years. However, the agronomic and physiological performances of high-quality indica rice (HQIR) under different nitrogen(N) application conditions in southern China are little known. Two-year consecutive field experiments were conducted with two HQIR and two ordinary-quality indica rice (OQIR) varieties under moderate and high N application rates, with yield and yield components, biomass, N up-take, and their related traits investigated. We found that grain yields of HQIR were slightly de-creased, but grain yields of OQIR were significantly increased by 6.60%-8.88% under high N rate compared with moderate N rate in both years. Thereby, OQIR produced 8.34%-11.87% and 22.00%-22.50% higher grain yield than HQIR under moderate and high N rates, respectively. The different responses of grain yield to N application rates were mainly due to decreased grain set-ting rate in HQIR and increased spikelets m-2 in OQIR under high N rate. Furthermore, high N rate significantly reduced pre-anthesis AE and improved grain-leaf area ratio, while did not in-crease post-anthesis DM compared with moderate N rate in HQIR, which might result in carbon metabolic deterioration and imbalance of source-sink relationship and subsequently lower supply of carbohydrate to panicle. Our results suggest that a moderate N rate (165 kg N ha-1) is beneficial for HQIR varieties to balance the maximum grain yield and high quality in southern China
ARTICLE | doi:10.20944/preprints202305.1751.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: hydrographic network; Posidonia oceanica meadow; burial process; regression rate; Calabria region; Mediterranean Sea
Online: 25 May 2023 (07:24:36 CEST)
In the Mediterranean Sea, there are two critical issues affecting marine benthic biocenosis: the sedimentation process and the increasing trend in marine biodiversity loss. These processes are very marked along the western side of Calabria coastline where siltation is one of the main reasons for the regression of Posidonia beds in the regional coastal waters. This research aims to investigate the relationships between the geomorphological features of the debris source areas, represented by fluvial basins, and the distribution of Posidonia meadows. So, a geomorphological study of the Tyrrhenian fluvial basins with area greater than 200 km2 and its correlation with the mapping of the meadows in the Calabria Tyrrhenian waters was carried out. Furthermore, in order to assess the increased level of burial in a Posidonia oceanica meadow and its health state over time, a program of Posidonia monitoring was undertaken between 2000 and 2010, in a test area located in the Marine Regional Park of Isca (Calabria, Southern Italy). The results of this survey highlighted that, at the beginning of the study period, for a silting rate of 4 - 5 cm/year, the meadow suffered a reduction of its photosynthetic ratio with a rate of mortality of 50%. In the following years, the siltation rate reach 12 cm/year in 2010 and the meadow began to disappear. Therefore, the marine pollution by sedimentation represents a serious factor for the regression of Posidonia oceanica meadows, enhancing the risk of a gradual loss in marine biodiversity.
ARTICLE | doi:10.20944/preprints202305.1744.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Frankenia; Frankeniaceae; nomenclature; ITS phylogeny; plant endemics; plant morphology; southern African flora; taxonomy
Online: 25 May 2023 (05:44:36 CEST)
The taxonomic identity and phylogenetic relationships of several southern African perennial taxa related to Frankenia repens are discussed. In particular, F. nodiflora Lam., a misunderstood species described from the Cape region and synonymised to F. pulverulenta, is restored for plants endemic to salt-pans and riverbeds in the coastal lowlands across the Cape plains (Western Cape Province, South Africa). Further, a revision of morphologically close plants, usually identified as F. pulverulenta or F. repens, also occurring in similar saline ecosystems of the inland western South Africa revealed the existence of two distinct new entities not matching any described taxa of the genus. Molecular analyses of nuclear ribosomal (ITS1-5.8S-ITS2 region) DNA sequence data together with morphological divergence allow recognition of those taxa at species rank, within an independent lineage close to F. repens. In consequence, two new species are described in the so-called “F. repens group”: F. nummularia from the Nama-Karoo Biome (Western Cape and Northern Cape Provinces), and F. namaquana from the Succulent Karoo Biome (Northern Cape Province). Full morphological description and type designation are reported for each accepted species, as well as data on ecology, habitat, distribution and taxonomic relationships to other close relatives are given. Further, an identification key is presented to facilitate recognition of the southern African taxa of Frankenia.
ARTICLE | doi:10.20944/preprints202305.1701.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: ITS phylogeny; plant endemics; plant morphology; South African flora; Spergularia; Sperguleae; taxonomy; trnL-trnF phylogeny.
Online: 24 May 2023 (05:20:49 CEST)
The name “Spergularia hanoverensis Simon” has been misapplied for an endemic taxon confined to inland semi-desert ecosystems in central-western South Africa. It is commonly accepted to be a small annual species occurring in saline habitats in a wide elevation range, but its real identity still remains obscure. In the context of a taxonomic and phylogenetic research on the African species of Spergularia, we found that the name apparently was never validly published still. After revision of herbarium material housed in the South African herbaria, a voucher collected from Hanover was found at PRE bearing some labels handwritten by E. Simon that suggest it might be an intended type for the name. Additional herbarium material and wild populations from Karoo region were identified that matched the samples in that voucher, and taxonomic research was conducted to clarify their identity. Those Karoo plants show a woody dense compact habit, woody perennial at base; stems prostrate to ascendent; leaves entirely glabrous, somewhat glaucous; with large white-hyaline conspicuous stipules; inflorescence glanduliferous, many-flowered subdichasial cyme, with minute bracts; flowers small, with white petals about equalling sepals, stamens 78, and styles free from base; capsule small, with seeds dimorphic, unwinged to broadly winged, with testa always densely tuberculate, among other characters. Molecular analyses of plastid (trnL-trnF region) and nuclear ribosomal (5.8S-ITS2 region) DNA sequence data support morphological differentiation of the Karoo plants, for which the name S. hanoverensis is here effectively published. A full morphological description, as well as data on ecology, habitat, distribution, and taxonomic and phylogenetic relationships of S. hanoverensis are compared to other members of the “South African group”, namely S. glandulosa. S. namaquensis, and S. quartzicola, from which the new species considerably differs. Adaptative significance of dimorphic seeds of S. hanoverensis is briefly commented in context to habitat preference of the species. An identification key is presented for the South African related taxa.
ARTICLE | doi:10.20944/preprints202305.1669.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Phytometabolites; ethnobotany; polyphenols; antiviral activity; molecular docking
Online: 24 May 2023 (02:30:24 CEST)
Traditional medicine is one of the main bases for studying and discovering natural sources of phytometabolites with antiviral properties. This research aims to demonstrate that the medicinal plants used as a treatment of viral diseases in the La Libertad region have, in fact, antiviral ac-tivity. The study evaluated the ethnobotany of the 8 most widely used medicinal plants in the region (Azadirachta indica A. Juss. “paraíso”, Caesalpinia spinosa (Molina) Kuntze “tara”, Citrus limon (L.) Osbeck “limón”, Clinopodium pulchellum (Kunth) Govaerts “panizara”, Cordia lutea Lam. “overo”, Ocimum basilicum L. “albahaca”, Schinus molle L. “molle”, and Taraxacum campylodes G.E. Haglund “diente de león”). The phytometabolites responsible for the antiviral activity were identified by LC-MS and evaluated in silico against the viral proteins NS2B/NS3 (DENV-2), NS5B (HCV), and ICP27 (HSV-1) using molecular docking in Autodock Vina and UCSF Chimera. The presence of five polyphenols (chlorogenic acid, gallic acid, caffeic acid, rosmarinic acid, and rutin) was found and, in the in silico test, the antiviral activity of chlorogenic acid stood out against DENV-2 and HCV, rutin against HCV and HSV-1, rosmarinic acid against DENV-2 and HCV. Therefore, it is verified that the medicinal plants studied have antiviral activity, which supports their use in traditional medicine
ARTICLE | doi:10.20944/preprints202305.1588.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: multi-stress responses; Arabidopsis; comparative transcriptomics; Pachycladon; cross-species comparison; network analysis
Online: 23 May 2023 (10:47:08 CEST)
The environment is seldom optimal for plant growth and changes in abiotic and biotic signals, including temperature, water availability, radiation and pests, induce plant responses to optimise survival. The New Zealand native plant species and close relative to Arabidopsis thaliana, Pachycladon cheesemanii grows under environmental conditions that are unsustainable for many plant species. Here we compare the responses of both plant species to different stressors (low temperature, salt and UV-B radiation) to help understand how P. cheesemanii can grow in such harsh environments. The stress transcriptomes were then determined and comparative transcriptome and network analyses discovered similar and unique responses within species between different stresses, and between the two plant species. A number of widely studied plant stress processes were highly conserved in A. thaliana and P. cheesemanii. However, in response to cold stress, Gene Ontology terms related to glycosinolate metabolism were only enriched in P. cheesemanii. Salt stress was associated with alteration of the cuticle and proline biosynthesis in A. thaliana and P. cheesemanii, respectively. Anthocyanin production may be a strategy to cope with UV-B radiation stress in P. cheesemanii only. These results allowed us to construct broad stress response pathways in A. thaliana and P. cheesemanii and identify possible novel plant strategies that help mitigate environmental stress.
ARTICLE | doi:10.20944/preprints202305.1530.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Abiotic stresses; Molecular breeding; Machine learning; Responsive genes; Adapted crops
Online: 22 May 2023 (15:29:12 CEST)
Plants have a natural protective process of altering their genetic molecules in response to changing environments. To uncover the genetic potential of plants, it is crucial to understand how they adapt to adverse conditions by analyzing their genetic molecules. In the study, we focused on understanding the responsive genes of tomatoes under drought conditions. We analyzed RNASeq data from different Tomato genotypes, tissue types, and different drought durations. We used a time series scale to identify early and late drought-responsive gene modules and applied a machine learning method to identify the best responsive genes. We found six candidate genes of Tomato (ASCT, FLA2, BAG5, DCL2b, NFP7.3, and ADC1) that were responsive to drought. We further constructed their protein-protein interaction network to identify their potential interactors and found them drought responsive proteins. The candidate genes can help to explore the adaptation of tomato plants under drought conditions. The identification of these candidate genes and modules can have far-reaching implications for molecular breeding and genome editing in Tomato, providing insights into the molecular mechanisms that underlie drought adaptation. This research underscores the importance of the genetic basis of plant adaptation, particularly in changing climates and growing populations.
REVIEW | doi:10.20944/preprints202305.1479.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: calcium homeostasis; AGPs; proton pump; cell wall
Online: 22 May 2023 (08:55:24 CEST)
Since Darwin’s “Power of movement in plants” the precise mechanism of oscillatory plant growth remains elusive. Hence the search continues for the hypothetical growth oscillator that regulates a huge range of growth phenomena ranging from circumnutation to pollen tube tip growth and stomatal movements. Oscillators are essentially simple devices with few components. A universal growth oscillator with only four major components became apparent recently with the discovery of a missing component, notably arabinogalactan glycoproteins (AGPs) that store dynamic Ca2+ at the cell surface. Demonstrably, auxin-activated proton pumps, AGPs, Ca2+ channels and auxin efflux “PIN” proteins, embedded in the plasma membrane, combine to generate cytosolic Ca2+ oscillations that ultimately regulate oscillatory growth: Hechtian adhesion of the plasma membrane to the cell wall and auxin-activated proton pumps trigger the release of dynamic Ca2+ stored in periplasmic AGP monolayers. These four major components represent a molecular PINball machine a strong visual metaphor that also recognizes auxin efflux “PIN” proteins as an essential component. Proton “pinballs” dissociate Ca2+ ions bound by paired glucuronic acid residues of AGP glycomodules, hence reassesses the role of proton pumps. It shifts the prevalent paradigm away from the recalcitrant “acid growth” theory that proposes direct action on cell wall properties, with an alternative explanation that connects proton pumps to Ca2+ signaling with dynamic Ca2+ storage by AGPs, auxin transport by auxin-efflux PIN proteins and Ca2+ channels. The extensive Ca2+ signalling literature of plants ignores arabinogalactan proteins (AGPs). Such scepticism leads us to reconsider the validity of the universal growth oscillator proposed here with some exceptions that involve marine plants and perhaps the most complex stress-test, stomatal regulation.
ARTICLE | doi:10.20944/preprints202305.1433.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Japanese apricot; scab; resistance; genome-wide association study (GWAS)
Online: 19 May 2023 (10:46:02 CEST)
Japanese apricot (Prunus mume) is a culturally and economically important fruit tree in East Asia. ‘Nanko’, the primary cultivar of the Japanese apricot well known in Japan, usually suffers from scab, a disease caused by Venturia carpophila. Scab results in the development of black spots on the fruit surface, which considerably reduces its commercial value. Despite being an economic concern for Japanese apricot, there have been few reports on the phenotypic variation in scab resistance/susceptibility, the underlying genetic factors, and the development of DNA markers. Therefore, in this study, we performed a comprehensive trait analysis for scab resistance and susceptibility for four years and conducted a genome-wide association study (GWAS) to identify the associated loci. The results showed that significant GWAS peaks were detected in 2017 and 2018. Promising candidate gene encoding domains associated with disease resistance were found at the nine single-nucleotide polymorphisms (SNPs) identified in 2017 and 2018. These SNPs were thought to be associated with scab susceptibility of ‘Nanko’ lineages. These findings shed light on the mechanisms of scab resistance in P. mume and will assist future breeding programs to improve scab resistance in ‘Nanko’ lineages.
ARTICLE | doi:10.20944/preprints202305.1364.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Ceratonia siliqua L.; Morocco; HPLC-DAD; Phenolics; Antioxidant activity; Antimicrobial activitiy; cytotoxicity; breast cancer; genotoxicity
Online: 19 May 2023 (03:23:35 CEST)
The botanical species Ceratonia siliqua L., commonly referred to as the Carob tree, and locally as “L’Kharrûb”, holds significance as an agro-sylvo-pastoral species, and is traditionally utilized in Morocco for treating a variety of ailments. This current investigation aims to ascertain the antioxidant, antimicrobial, and cytotoxic properties of the ethanolic extract of C. siliqua leaves (CSEE). Initially, we analyzed the chemical composition of CSEE through high-performance liquid chromatography with Diode-Array Detection (HPLC-DAD). Subsequently, we conducted various assessments, including DPPH scavenging capacity, β-carotene bleaching assay, ABTS scavenging, and total antioxidant capacity assays, to evaluate the antioxidant activity of the extract. In this study, we investigated the antimicrobial properties of CSEE against five bacterial strains (two gram-positive, Staphylococcus aureus, and Enterococcus faecalis; and three gram-negative bacteria, Escherichia coli, Escherichia vekanda, and Pseudomonas aeruginosa) and two fungi (Candida albicans, and Geotrichum candidum). Additionally, we evaluated the cytotoxicity of CSEE on three human breast cancer cell lines (MCF-7, MDA-MB-231, and MDA-MB-436) and assessed the potential genotoxicity of the extract using the comet assay. Through HPLC-DAD analysis, we determined that phenolic acids and flavonoids were the primary constituents of the CSEE extract. The results of the DPPH test indicated a potent scavenging capacity of the extract with an IC50 of 302.78 ± 7.55 µg/mL, which was comparable to that of ascorbic acid with an IC50 of 260.24 ± 6.45 µg/mL. Similarly, the β-carotene test demonstrated an IC50 of 352.06 ± 12.16 µg/mL, signifying the extract's potential to inhibit oxidative damage. The ABTS assay revealed IC50 values of 48.13 ± 3.66 TE µmol/mL, indicating a strong ability of CSEE to scavenge ABTS radicals, and the TAC assay demonstrated an IC50 value of 165 ± 7.66 µg AAE/mg. The results suggest that the CSEE extract had potent antioxidant activity. Regarding its antimicrobial activity, the CSEE extract was effective against all five tested bacterial strains, indicating its broad-spectrum antibacterial properties. However, it only showed moderate activity against the two tested fungal strains, suggesting it may not be as effective against fungi. The CSEE exhibited a noteworthy dose-dependent inhibitory activity against all the tested tumor cell lines in vitro. The extract did not induce DNA damage at the concentrations of 6.25, 12.5, 25, and 50 µg/ml, as assessed by the comet assay. However, the 100 µg/ml concentration of CSEE resulted in a significant genotoxic effect compared to the negative control. A computational analysis was conducted to determine the physicochemical and pharmacokinetic characteristics of the constituent molecules present in the extract. The Prediction of Activity Spectra of Substances (PASS) test was employed to forecast the potential biological activities of these molecules. Additionally, the toxicity of the molecules was evaluated using the Protox II webserver.
REVIEW | doi:10.20944/preprints202305.1327.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Plum consumption; Consumer Quality Index; flesh breakdown; temperature management; critical bruising thresholds; maximum maturity; late harvest; firmness; SSC
Online: 18 May 2023 (10:25:20 CEST)
Plums are primarily marketed for fresh consumption, canning, freezing, jam and jelly. Unfortunately, plum consumption has remained steady or declined. Consumers complain about a lack of flavor quality but are willing to pay for higher quality. Thus, lack of flavor and cold storage disorders are the main barriers to consumption. Plum cultivars are susceptible to gel breakdown, flesh browning and ‘off flavors’. Consumer acceptance and postharvest life are highly dependent on genotype, quality attributes, harvest date and proper postharvest handling. A consumer quality index (CQI) based on soluble solids concentration (SSC) and minimum firmness is proposed to maximize flavor and postharvest life. In most cases, late harvest increases quality attributes. Our work and industry experience demonstrated that using critical bruising thresholds (CBT) based on minimum firmness measured at harvest acts as a reliable predictor of how late to harvest safely for maximum visual and sensory quality. Plums are well adapted to late harvest because of their low susceptibility to bruising damage, but proper postharvest temperature management and marketing within the potential market life are necessary to maintain flavor and avoid the onset of storage disorders. Thus, to maximize flavor and postharvest life, a CQI based on SSC and minimum firmness measured at consumption is proposed. This article provides guidance on using this CQI, combined with proper postharvest handling techniques such as correct harvest date determination and temperature management, to maintain quality and increase consumption.
ARTICLE | doi:10.20944/preprints202305.1271.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Chenopodiaceae; Salicornioideae; Salicornieae; Kazakhstan; hybrid; tetraploid
Online: 18 May 2023 (05:09:25 CEST)
The article presents data on phylogeny, genome size, and ploidy of species of the genus Kalidium Moq. in the flora of Kazakhstan. Genus Kalidium belongs to the tribe Salicornieae of the subfamily Salicornioideae of the family Chenopodiaceae and unites 8 species, the main range of which covers the Iranian-Turanian and Central Asian deserts. There are 4 species in the flora of Kazakhstan: K. foliatum, K. caspicum, K. schrenkianum and the recently described K. juniperinum. Populations of species of the genus Kalidium in the saline deserts of Kazakhstan occupy large areas, often forming monodominant communities. Sometimes there is a joint growth of 2 and very rarely 3 species of the genus. During the period of fieldwork (2021-2022), populations were identified in which these species grew together with a predominance, in most cases, of K. caspicum. Samples of representatives from 15 populations were collected for research. Selected plant samples were studied by flow cytometry to determine plant ploidy. Sequencing of nrITS and two chloroplast fragments were used to build a phylogenetic tree, including sequences from the NCBI database., A phylogenetic tree of species of the genus Kalidium was compiled which considers previously published data. In the valley of the middle reaches of the Syrdarya River tetraploid populations of K. caspicum were found. A hybrid between K. foliatum and K. caspicum was found in the Ili River valley (Almaty region, Uigur district). To identify phylogenetic processes at the intraspecific level, the SCoT (Start codon targeted) fingerprinting method was used.
ARTICLE | doi:10.20944/preprints202305.1117.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Palynology; Taxonomy; Pollen morphology; Convolvulaceae; Carajás.
Online: 16 May 2023 (07:24:00 CEST)
Canga vegetation has high ecological importance in the Serra dos Carajás, southeastern Amazonia, but it coexists with the potential threat of large-scale iron ore mining. Considering Convolvulaceae, this canga environment has only 17 species, and 15 of these species had their pollen grains described in detail in this present work, aiming to contribute to the taxonomic knowledge of critically endangered plants, including Ipomoea cavalcantei. Pollen grains were examined by light and scanning electron microscopy, and the morphological parameters obtained were statistically analyzed using principal component analysis. Therefore, Aniseia cernua was described for the first time in the literature. In general, the echinae morphology were the main differentiating character among the Ipomoea species and was the basis for the proposed pollen key. The family Convolvulaceae in Carajás is eurypalynous, and the genus Ipomoea may be classified as stenopalynous. The set of morphological characters statically treated and correlated was effective for the separation of Ipomoea.
ARTICLE | doi:10.20944/preprints202305.1058.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Brassica napus; Plant Cysteine Oxidase (PCO); gene expression; abiotic stress
Online: 15 May 2023 (15:35:43 CEST)
Plant Cysteine Oxidase (PCO) is a plant O2-sensing enzyme of catalyzing oxidation of cysteine to Cys-sulfinic acid at the N-termini of target proteins. To better understand the Brassica napus PCO gene family, PCO genes in B. napus and related species were analyzed. In this study, 20, 7 and 8 PCO genes were identified in Brassica napus, Brassica rapa and Brassica oleracea, respectively. According to phylogenetic analysis, the PCOs were divided into five groups: PCO1, PCO2, PCO3, PCO4 and PCO5. Gene organization and motif distribution analysis suggested that PCO gene family was relatively conserved during evolution. Expression analysis showed that PCO genes were expressed in different tissues at different developmental stages. Interestingly, most of the Bna/Br/BoPCO5 members were expressed in leaves, roots, flowers, buds and siliques, suggesting an important role in both vegetative and reproductive development. Expression of BnaPCO was induced by various abiotic stress, especially waterlogging stress, which was consistent with the result of cis-element analysis. In this study, the PCO gene family of Brassicaceae was analyzed for the first time, which contributes to a comprehensive understanding of the origin and evolution of PCO genes in Brassicaceae and the function of BnaPCO in regulating plant responses to abiotic stresses.
ARTICLE | doi:10.20944/preprints202305.1005.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: auxin; signaling; gene expression; transcription regulation; auxin receptors; Aux/IAA proteins; ARF transcription factors; potato cultivars
Online: 15 May 2023 (09:02:05 CEST)
It has long been known that auxins play a promoting role in tuber formation and stress tolerance in potatoes. Our study aimed to identify and characterize the complete sets of auxin-related genes that presumably constitute the entire auxin signaling system in potato (Solanum tuberosum L.). The corresponding genes were retrieved from sequenced genomes of the doubled monoploid S. tuberosum DM1-3-516-R44 (DM) of the Phureja group, the heterozygous diploid line RH89-039-16 (RH), and the autotetraploid cultivar Otava. Both canonical and noncanonical auxin signaling pathways were considered. Phylogenetic and domain analyzes of deduced proteins were supplemented by their expression profiling and 3D molecular modeling. Total number of potato genes/proteins involved in canonical auxin signaling is 43and 100 for monoploid DM and tetraploid Otava, respectively. Among studied potatoes, spectra of expressed genes associated with auxin signaling were partly cultivar-specific and quite different from analogous spectrum in Arabidopsis. Orthologs of noncanonical auxin signaling genes have also been identified and characterized in detail. Results show that some known noncanonical pathways are low probable in potato. Thus, according to cumulative data, potatoes use a variety of pathways for auxin signaling, where some important features of these pathways may be variable and even species-specific.
COMMUNICATION | doi:10.20944/preprints202305.0950.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: genebank; digital phenotyping; RDA-Genebank; Nagoya Protocol
Online: 12 May 2023 (13:31:37 CEST)
The National Agrobiodiversity Center under the Rural Development Administration (RDA) in Jeonju, Republic of Korea, is the largest international genebank of Korea. The National Agrobi-odiversity Center has continuously been making efforts to introduce overseas genetic resources to its collection and has currently grown into a world-class PGR holding genebank. Currently, several steps are undertaken to, improve the accessibility of the collection to national as well as international researchers, improve data available on the resources and amend the passport in-formation of the accessions. With the implementation of the Nagoya Protocol, the origin of ge-netic resources is being highlighted as an important input in the passport information of germplasms. The RDA-Genebank actively responds to the Nagoya Protocol by supplementing passport data of resources lacking information on the origin of germplasm. In addition, a large number of conserved resources are continuously multiplied, and agronomic traits are investi-gated concurrently. With the traditional methods of characterization of the germplasm requiring a significant amount of time and effort, we have intiated high-throughput phenotyping using digital techniques to improve our germplasm data. Primarily, we have started adding seed phenotype information followed by measuring root phenotypes which are stored under agro-nomic traits. This may be the initial step for a germplasm center to use large-scale high-throughput techniques for their collection. In this shortcommunication, we aim to provide an introduction to the RDA- Genebank, adopted international standards, and establishment of high throughput phenotyping techniques for improvement of passport information.
ARTICLE | doi:10.20944/preprints202305.0943.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: barley; Hordeum vulgare ssp; vulgare; Wheat dwarf virus (WDV); leafhoppers; resistance; tolerance; single nucleotide polymorphisms (SNPs); marker; QTL
Online: 12 May 2023 (11:50:31 CEST)
Wheat dwarf virus (WDV) causes an important vector transmitted virus disease, which leads to significant yield losses in barley production. Due to the fact, that at the moment no plant protection products are approved to combat the vector Psammotettix alienus and this disease cannot be controlled by chemical means, therefore the use of WDV resistant or tolerant genotypes is the most efficient method to control and reduce negative effects of WDV on barley growth and production. In this study, a set of 480 barley genotypes were screened to identify genotypic differences in response to WDV and five traits were assessed under infected and non-infected conditions. In total, 32 genotypes showed resistance or tolerance against WDV. Subsequently, the phenotypic data of 191 out of 480 genotypes combined with 34,408 single nucleotide polymorphisms (SNPs) in a genome wide association study to identify quantitative trait loci (QTLs) and markers linked to resistance/tolerance to WDV, using Tassel, GAPIT, and FARM CPU. In total, 1, 3, 2, 2 and 1 significantly associated markers on chromosomes 3H, 4H, 5H and 7H identified by all three methods for ELISA-60, relative performance of total grain weight, plant height, number of ears per plant and thousand grain weight, respectively.
ARTICLE | doi:10.20944/preprints202305.0928.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Fabaceae; transcriptomics; proteomics; metabolomics; low doses; abiotic stress
Online: 12 May 2023 (10:39:57 CEST)
Our understanding of the long-term consequences of chronic ionising radiation for living organisms remains scarce. Modern molecular biology techniques are helpful tools for researching pollutant effects on biota. To reveal the molecular phenotype of plants growing under chronic radiation exposure, we sampled Vicia cracca L. plants in the Chernobyl Exclusion Zone and in areas with normal radiation backgrounds. We performed a detailed analysis of soil and gene expression patterns, and made coordinated multi-omics analyses of plant samples, including transcriptomics, proteomics, and metabolomics. Chronic exposure to ionising radiation induced complex and multidirectional changes, including significant alterations in the metabolism and gene expression patterns of irradiated plants. We revealed profound changes in carbon metabolism, nitrogen reallocation, and photosynthesis. These plants were characterised by increased DNA damage, redox imbalance, and stress response reactions. The upregulation of histones, chaperones, peroxidases, and secondary metabolism were noted.
ARTICLE | doi:10.20944/preprints202305.0627.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Non-headed Chinese cabbage; heat stress; physiological mechanism; heat-resistant varieties
Online: 9 May 2023 (09:40:07 CEST)
Under the increasingly severe global heat threat, continuous high temperature has far-reaching effects on plant growth and development and become a major constraint to crop production. The development of heat-resistant varieties has become research hotspot in many fields, and it is also necessary to establish effective identification methods. In this study, twenty Brassica rapa varieties were selected to to investigate the physiological and biochemical characteristics under heat stress, explore the relationship between physiological response and the heat resistance mechanism, select some typical heat-resistant and heat-sensitive varieties. The effects of photosynthetic electron transfer and antioxidant pathway on heat resistance of Brassica rapa were identified. These findings will providing an important reference for the physiological regulation and identification method of high-temperature stress in plants.
REVIEW | doi:10.20944/preprints202305.0622.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Begomovirus; Whitefly; Viral genome; Viral transmission; Host-vector-pathogen interaction; Host defense
Online: 9 May 2023 (09:15:31 CEST)
Begomovirus infection in plant causes a great economic loss in many countries every year. Increasing rate of the infectivity of this single stranded DNA virus forces to study of its transmission in detail for the necessary researches regarding the control of this disease. This pathogenic virus is whitefly vector borne and transferred from one plant to another plant during the suckling of phloem sap by that vector. Viral transmissibility through this insect vector may depend on the genetic variations within the cryptic species groups. Two distinct categories of begomoviruses viz., bipartite and monopartite types consist of different genome organization. Virion particles modify the intracellular environment of the host according to their need of replication and survival. Viral replication takes place through RCR as well as RDR methods. Interplay among host, vector and pathogen is crucial for the establishment of infection. Several endosymbiotic organisms living within the insect vector also have vital role here. Being infected with this virus, host plant responds with defensive activities like TGS, PTGS, autophagy, hormonal regulation, metabolic alteration etc. However, virus also counteracts those through the manipulation of several pathways of cellular events. It is necessary to study in different directions and utilize advanced molecular biological techniques to develop begomovirus resistance within plants.
ARTICLE | doi:10.20944/preprints202305.0569.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Occurrence; larval density; population; cropping system; farming practice
Online: 9 May 2023 (04:57:38 CEST)
The false codling moth (FCM), Thaumatotibia leucotreta (Meyrick), is believed to have originated from Ethiopia and sub-Saharan Africa. Currently, this pest has extensively spread and is found in most parts of Africa, with records in approximately 40 countries in over 100 host plant species. Despite Thaumatotibia leucotreta being the leading cause of interceptions of Capsicum and cut flowers exported by Kenya to the European Union, information on abundance and damage levels inflicted on capsicum is limited. The objective of the study was to assess the abundance and damage levels of T. leucotreta on capsicum in the selected counties in Lower Eastern Kenya (Kitui, Machakos, and Makueni counties). Higher T.leucotreta larval density per farm was recorded in Kitui County compared to other counties. In farms with capsicum only (not intercropped with other crops), the mean number of FCM larvae was relatively higher in Kitui. Farming practices such as the use of uncertified seeds and seedlings and the excessive use of pesticides may be the major contributors to high larval incidence in Kitui County.
ARTICLE | doi:10.20944/preprints202305.0339.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Banana; fine mapping; quantitative trait locus; Musa acuminata ssp. malaccensis; Fusarium wilt; Fusarium oxysporum f. sp. cubense; Tropical Race 4; Subtropical Race 4; marker assisted selection; resistance gene expression; receptor-like kinase; RNAseq
Online: 5 May 2023 (09:51:49 CEST)
Fusarium wilt of banana is a devastating disease that has decimated banana production worldwide. Host resistance to Fusarium oxysporum f. sp. cubense (Foc), the causal agent of this disease, is genetically dissected in this study using two Musa acuminata ssp. malaccensis segregating populations segregating for Foc Tropical (TR4) and Subtropical (STR4) race 4 resistance. Marker loci and trait association using 11 SNP-based PCR markers allowed the candidate region to be delimited to a 12.9 cM genetic interval corresponding to a 959 kb region on Chromosome 3 of ‘DH-Pahang’ reference assembly v4. Within this region, there is a cluster of pattern recognition receptors, namely leucine rich repeat ectodomain containing receptor-like protein kinases, cysteine-rich cell wall associated protein kinases, and leaf rust 10 disease-resistance locus receptor-like proteins positioned in an interspersed arrangement. Their transcript levels were rapidly upregulated in the resistant but not in susceptible F2 progenies at the onset of infection. This suggests that one or several of these genes may control resistance at this locus. To confirm the segregation of single-gene resistance, we generated an inter-cross between the resistant parent ‘Ma850’ and a susceptible line ‘Ma848’, to show that the STR4 resistance co-segregated with marker ‘28820’ at this locus. Finally, an informative SNP marker 29730 allowed the locus specific resistance to be assessed in a collection of diploid and polyploid banana plants. Out of the 60 lines screened, 22 lines were predicted to carry resistance at this locus, including lines known to be TR4 resistant, such as ‘Pahang’, ‘SH-3362’, ‘SH-3217’, ‘Ma-ITC0250’, and ‘DH-Pahang/CIRAD 930’. Additional screening in the International Institute for Tropical Agriculture’s collection suggests that the dominant allele is common among in the elite ‘Matooke’ NARITA hybrids, as well as in other triploid or tetraploid hybrids derived from East African highland bananas. Fine-mapping and candidate gene identification will allow characterization of molecular mechanisms underlying TR4 resistance. The markers developed in this study can now aid the marker-assisted selection of TR4 resistance in breeding programs around the world.
ARTICLE | doi:10.20944/preprints202305.0337.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Dendrobium officinale; leaf color; qRT-PCR; reference gene; leaf color mutant
Online: 5 May 2023 (09:34:44 CEST)
Leaf color mutants (LCMs) are important resources for studying diverse metabolic processes such as chloroplast biogenesis and differentiation, pigments’ biosynthesis and accumulation, and photosynthesis. However, in Dendrobium officinale, LCMs are yet to be fully studied and exploited due to the unavailability of reliable RGs (reference genes) for qRT-PCR (quantitative real-time reverse transcription PCR) normalization. Hence, this study took advantage of previously released transcriptome data to select and evaluate the suitability of ten candidate RGs, including Actin (Actin), polyubiquitin (UBQ), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), elongation factor 1-α (EF1α), β-tubulin (β-TUB), α-tubulin (α-TUB), 60S ribosomal protein L13-1 (RPL13AD), aquaporin PIP1-2 (PIP1-2), Intima protein (ALB3) and Cyclin (CYCB1-2) for normalizing leaf color-related genes’ expression levels via qRT-PCR. Stability rankings analysis via common software Best-Keeper, GeNorm, and NormFinder disclosed that both ten genes met the requirements of RGs. Of them, EF1α exhibited the highest stability and was selected as the most reliable. The reliability and accuracy of EF1α were confirmed through qRT-PCR analysis of fifteen chlorophyll pathway-related genes. The expression patterns of these genes via EF1α normalization were consistent with the results by RNA-Seq. Our results will pave the way for molecular dissection of leaf color mutations in D. officinale.
ARTICLE | doi:10.20944/preprints202305.0301.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: boron toxicity; proteomic analysis; maize landrace; Zea mays
Online: 5 May 2023 (05:01:52 CEST)
Boron (B) toxicity is an important stress that negatively affects maize yield and quality production. The excessive B content in agricultural lands is a growing problem due to the increase in arid and semi-arid areas because of climate change. Recently, two Peruvian maize landraces, Sama and Pachía, were physiologically characterized based on their tolerance to B toxicity, the former being more tolerant to B excess than Pachía. However, many aspects regarding the molecular mechanisms of these two maize landraces against B toxicity are still unknown. In this study, a leaf proteomic analysis of Sama and Pachía was performed. Out of a total of 2793 proteins identified only 303 proteins were differentially accumulated. Functional analysis indicated that many of these proteins are involved in transcription and translation processes, amino acids metabolism, photosynthesis, carbohydrate metabolism, protein degradation, and protein stabilization and folding. Compared to Sama, Pachía had a higher number of differentially expressed proteins related to protein degradation, and transcription and translation processes under B toxicity conditions, which might reflect the greater protein damage caused by B toxicity in Pachía. Our results suggest that higher tolerance to B toxicity of Sama can be attributed to more stable photosynthesis that would avoid damage caused by stromal over-reduction under this stress condition.
ARTICLE | doi:10.20944/preprints202304.1276.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: transcription factors; interactome network; sex development; sex determination; Cucumber (Cucumis sativus); metabolomic processes
Online: 1 May 2023 (00:01:26 CEST)
Plant reproduction is a very important process on Earth from the perspective of biodiversity, biomass gain and crop productivity. It is therefore important to understand sex determination process and many researchers are investigating the molecular basis of this phenomenon. However, information on the influence of transcription factors (TFs) on this process is limited, although cucumber is a model plant in this regard. In the present study, based on RNA-seq data for differential gene expression (DEG) analyses, we aimed to investigate the regulatory TFs that may influence the metabolomic processes in the shoot apex containing the forming flower buds. Therefore, a robust TF database was established for the B10v3 cucumber genome. Sex-specific interactome network maps were generated, indicating the regulatory TFs by their effects on DEGs and further on processes leading to the formation of different sex flowers. The network analysis identified major families of regulatory TFs. The most abundant families were: MYB, AP2/ERF, NAC and bZIP, and those with the greatest impact on developmental processes were identified, namely the AP/ERF family, followed by DOF, MYB, MADS and others. Thus, the central nodes and key regulators in the networks were identified with respect to male, female and hermaphrodite. Here, we proposed the first model of the regulatory network of TFs that influences the metabolism of sex development in cucumber. These findings may help to understand the molecular genetics and functional mechanisms underlying sex determination processes.
ARTICLE | doi:10.20944/preprints202304.1122.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: plant cell culture; elicitation; methyl jasmonate; paclitaxel; plant secondary metabolism; C14-hydroxylated taxoids
Online: 28 April 2023 (05:28:39 CEST)
The effects of methyl jasmonate (MeJ) on growth and taxoid formation in the cell culture of Himalayan yew was investigated for elucidate the specifics of the action of phytohormones on dedifferentiated plant cells in vitro. The characteristics of the same suspension culture of Taxus wallichiana was compared in 2017 ("young culture") and in 2022 ("old culture") - 1.5 or 6 years after culture induction, respectively. Cells were grown in flasks and bioreactors, MeJ (100 µM) was added at the exponential growth phase. It was found that cell culture demonstrated good growth (dry weight (DW) accumulation 10–18 g/l, specific growth rate µ = 0.15–0.35 day-1) regardless of "age", cultivation system and MeJ addition. UPLC–ESI-MS analysis showed the presence of C14-hydroxylated taxoids (yunnanxane, taxuyunnanine C, sinenxane C, sinenxane B) in cell biomass in the amounts comparable to plants. The content of C14-OH taxoids during 5 years of cultivation increased by 3-5 times. It was 0.2–1.6 mg/g DW for "young culture” and 0.6-10.1 mg/g for “old culture” depending on cultivation conditions. The ratio of individual compounds changed also: in the "young culture" was predominant yunnanxane, in the "old culture" - sinenxane C. Important that C13-hydroxylated taxoids were found in trace amounts only in the "young culture” (below 0.05 mg/g DW) and were not detected in the "old culture”. The response to MeJ was radically different depending on culture’s «age». In the “young culture”, exogenous MeJ had no effect on the content of C14-OH com-pounds, but significantly (almost 10 times) increased the content of C13-OH compounds. In particular, paclitaxel concentration was elevated up to 0.12–0.19 mg/g DW, which is comparable to its content in the bark of yew trees. By contrast, MeJ added to the "old culture” had minor effect on the synthesis of C13-OH toxoids that appeared in trace amounts only (below 3.5 µg/g DW for paclitaxel) but notably increased the content of C14-OH compounds (1.5–2.0 times in flasks and 5–8 times in bioreactors). These findings suggest that hormonal signaling in dedifferentiated yew cells grown in vitro is different from that in plants and change with culture age. This might be a result of the high level of heterogeneity of cells in vitro and their constant auto-selection for proliferate intensity which leads to predominant formation of C14-OH taxoids versus C13-OH taxoids and modified cell response to exogenous MeJ treatment. These results have both fundamental and practical biotechnological application.
REVIEW | doi:10.20944/preprints202304.0666.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Heavy metal; Mineral Nutrition; Phytohormones; Selenium
Online: 21 April 2023 (03:34:38 CEST)
Abstract: Heavy metals (HMs) contamination is one of the main among abiotic factors affecting crop productivity and also threatens human health via consuming metal contaminated crops as a food source. Over the past few years, HMs have drawn a lot of attention due to their increased use for commercial purposes and their harmful effects on plants and other life forms, thus threatening human survival. However, in recent years, several methods have been adopted to combat the harsh effects of HMs. After phytohormones, use of mineral nutrients such as selenium (Se) in the prevention of HM stress has been explored by the researchers more recently. Selenium is an important micronutrient widely known for its antioxidant properties in both plants and animals. Exogenous Se inhibits metal uptake and its translocation and also improves the antioxidant system, thus imparts resistance to HM toxicity in plants. Moreover, Se also regulates the production of various osmolytes in cells that helps in developing cell osmolarity. Selenium also induces the production of different types of secondary metabolites (SMs) that are also involved in plant's secondary defense mechanisms to different stresses. Uptake of mineral nutrients is a vital process for plant growth and development, which is also positively correlated with Se under metalloid toxicity. However, in order to understand the exact mechanism of Se in HM tolerance, different metabolic processes stimulated by Se and their pathways need to be explored. Hence, this review focuses on the role of Se on nutritional status, antioxidants metabolism, interaction with phytohormones and its role in the regulation of various genes involved in Se induced HM tolerance. Thus, this study will help researchers in the future for the improvement of HM tolerance via Se application in plants.
ARTICLE | doi:10.20944/preprints202304.0586.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Brassica napus L.; Shoot apical meristem (SAM); shoot branching; Transcriptome; Cytokinin
Online: 19 April 2023 (10:38:49 CEST)
Rapeseed (Brassica napus L.) is a globally important oilseed crop with various uses, including consumption of its succulent stems as a seasonal vegetable, but its uniaxial branching habit limits the stem yield. Therefore, developing a multi-stem rapeseed variety has become increasingly crucial. In this study, a nature mutant of wild type from germplasm resources with stable inheritance of the multi-stem trait (MS) was obtained and showed abnormal shoot apical meristem (SAM) development and increased main stem number compared to WT. Histological and scanning electron microscopy analyses revealed multiple SAMs in the MS mutant, while only a single SAM was found in WT. Compared to WT, the mutant exhibited increased accumulation of cytokinins (CKs), transcriptome and RT-qPCR analyses showed the expression of genes involved in CK biosynthesis and metabolism pathways were altered in MS mutant. These findings provide insight into the mechanism of multiple main stems formation in Brassica napus L. and lay a theoretical foundation for breeding multi-main stem rapeseed vegetable varieties.
ARTICLE | doi:10.20944/preprints202304.0574.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: ABA biosynthesis; ABA perception; Fragaria chiloensis; fruit ripening; NCED; PYR/PYL receptors; phylogenic analysis; RT-qPCR
Online: 19 April 2023 (08:43:03 CEST)
Hormones act as master ripening regulators. In non-climacteric fruit ABA plays a key role in ripening. Recently we confirmed in Fragaria chiloensis fruit that in response to ABA treatment the fruit induces ripening associated changes such as softening and color development. In consequence with these phenotypic changes, transcriptional variations associated with cell wall disassembly and anthocyanins biosynthesis were reported. As ABA stimulates ripening of F. chiloensis fruit, the molecular network involved in ABA metabolism was analyzed. Therefore, the expression level of genes involved in ABA biosynthesis and ABA perception were quantified during development of the fruit. Four NCED/CCDs and 6 PYR/PYLs family members were identified in F. chiloensis. Bioinformatics analyses confirmed the existence of key domains related to functional properties. Through RT-qPCR analyses the level of transcripts were quantified. FcNCED1 codifies a protein that displays crucial functional domains and the level of transcripts increased as the fruit develops and ripens, in parallel with the increment in ABA. In addition, FcPYL4 codifies for a functional ABA receptor and its expression follows an incremental pattern during ripening. The study concludes that FcNCED1 is involved in ABA biosynthesis, meanwhile FcPYL4 participates in ABA perception during ripening of F. chiloensis fruit.
ARTICLE | doi:10.20944/preprints202304.0493.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Autotetraploid; Potato; RNA-Seq; WGCNA analysis; Hub genes
Online: 18 April 2023 (05:25:28 CEST)
The formation and development of potato tissues and organs is a complex process regulated by a variety of genes and environmental factors. However, the regulatory mechanisms underlying the growth and development are still unclear. In this study, we used autotetraploid potato JC14 as experimental subject to analyze the transcriptome of root, stem and leaf at seedling, tuber formation and tuber expansion stages to explore the spatio-temporal expression pattern of genes and genetic development characteristics. The results identified thousands of differentially expressed genes and KEGG pathway enrichment analysis showed that these genes were mainly involved in defense response and carbohydrate metabolism pathways. A total of 12 co-expressed Gene modules were identified by Weighted Gene Co-expression Network Analysis (WGCNA), and 4 modules were screened out with the highest correlation with potato stem developmental traits. Core genes in the network were further investigated and functionally annotated by computing the connectivity of genes within the module. The results unveiled number of hub genes in stems at different developmental stages, including carbohydrate metabolism related genes, the defense response related genes, and transcription factors. These findings provide important leads for further understanding of the molecular regulation and genetic mechanisms of potato tissue development.
REVIEW | doi:10.20944/preprints202304.0367.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: species distribution modeling; machine learning; MaxEnt; bryophytes; climatic change.
Online: 14 April 2023 (10:35:42 CEST)
Species distribution modeling (SDM) has come a long way since its inception. Starting as simple bioclimatic envelope models based on expert knowledge, species distribution models (SDMs) have evolved into complex and sophisticated models that incorporate multiple sources of data and machine learning algorithms. Today, SDMs play a crucial role in addressing pressing conservation and management issues, including the impacts of climate change on species ranges and the as-sessment of species vulnerability to extinction. In this article, we will embark on a journey through the history, present, and future of SDM, exploring its evolution from bioclimatic envelopes to machine learning. We will also provide practical tips on how to use SDMs effectively and discuss the exciting future developments in this field. Whether you are a seasoned SDM expert or new to this field, this article will provide valuable insights into the exciting world of SDM. By exploring the rich history and current state of the field, we hope to shed light on the tremendous potential of SDM for improving our understanding of the distribution of species in a changing world.
ARTICLE | doi:10.20944/preprints202304.0240.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Dryopteris affinis ssp. affinis; Dryopteris oreades; fern; gametophyte; non-seed plants; proteome; STRING database
Online: 12 April 2023 (04:42:51 CEST)
Ferns and fern-allies, now known as Monylophytes, have received scant molecular attention, in relation to angiosperm group. The advent of high-throughput technologies allows to advance towards a greater knowledge of their elusive genome. In this work, samples of apogamous and sexual heart-shaped gametophytes from two ferns: the apomictic species Dryopteris affinis ssp. af-finisand its sexual relative Dryopteris oreades were extracted and identified. In total, a set of 218 proteins shared by these gametophytes were analysed by using the STRING database, and the proteome associated to metabolism, genetic information processing and responses to abitotic stress is discussed. Specifically, there are reported proteins involved in metabolism of carbohy-drates and lipids, biosynthesis of amino acids, metabolism of nucleotides, energy, and secondary compounds, oxido-reduction, transcription, translation, folding, sorting, and degradation, and response to abiotic stress. Some homologs of proteins found are MACCI-BOU (MAB1), MOSAIC DEATH 1 (MOD1), MAINTENANCE OF PHOTOSYSTEM II UNDER HIGH LIGHT 2 (MPH2), TRANSPARENT TESTA 5 (TT5), ALBINO OR GLASSY YELLOW 1 (AGY1), LEUCYL AMINOPEP-TIDASE 1 and 3 (LAP1 and LAP3), or LOW EXPRESSION OF OSMOTICALLY RESPONSIVE GENES 1 (LOS1). The interactome of the set of proteins was also studied, being the most common interac-tions database and textmining. All these data about the interactions that exist between the stud-ied proteins of the ferns D. affinis and D. oreades, together with the description of their biological function, might contribute to better understand the functioning and development of ferns as well as to fulfil gaps of knowledge in plant evolution.
ARTICLE | doi:10.20944/preprints202304.0179.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Acmella oleracea; Anti-oxidant; In vitro; Anti-bacterial; Methanol extract
Online: 11 April 2023 (03:09:50 CEST)
Acemella oleracea is known as toothache plant belongs to the family of Asteraceae. It is treated as a medicinal remedy like tuberculosis, illness, cough, rheumatism, and illness. This study was concentrated on the antioxidant, cytotoxic, antimicrobial & thrombolytic activities of methanol extract of Acmella oleracea leaves using in vitro model. The antioxidant activity was estimated as trolox equivalent antioxidant capacity utilizing the DPPH and reducing power tests. The plant extract was tested for its cytotoxic action using a brine shrimp lethality bioassay, thrombolytic activity using clot disruption, and antibacterial activity using a disc diffusion assay technique against four distinct gram-positive and gram-negative bacteria. IC50 value of standard ascorbic acid for DPPH was 7.8µg/ml and the IC50 of the methanol extract of Acmella oleracea leaves was 198.34µg/ml that was moderate effect at all compare with ascorbic acid. Thrombolytic assay of Streptokinase as a positive control showed 88.49% where the extract shows 18.69% lytic activity shows the assay. In this study, the sample of LC50 results of cytotoxicity assay was 1.431 µg/mL which can be treated as less activity. Moreover, the extracts showed low to moderate antibacterial activity against both gram-negative and gram-positive bacterial stains (zone of inhibition-10-26 mm). Vibrio Mimicus bacteria stains exhibited the highest level of activity, with a range of 23 for the diameter of the growth inhibition zone. The current review shows leaf extracts of Acmella oleracea may be used as a source of antioxidant and thrombolytic activity, as well as a significant source of antibacterial and anticancer substances. Further research is required to evaluate in-vivo the pharmacological activity of Acmella oleracea leaves in order to identify the essential metabolites and potential mechanisms.
ARTICLE | doi:10.20944/preprints202304.0058.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Aerobic Rice; Chlorosis; Iron Deficiency; Oryza; Wild Germplasm; IDIC; SPAD
Online: 5 April 2023 (11:34:36 CEST)
Transplanted rice cultivation has caused groundwater depletion in several regions globally. Direct-seeded rice under aerobic conditions is a water-saving alternative. However, under aerobic conditions, iron in the soil is oxidized from ferrous to ferric, which is not easily available for rice, resulting in iron deficiency induced chlorosis (IDIC) causing significant reduction in yield. Cultivated rice genotypes have limited variations for IDIC tolerance, while wild Oryza germplasm could be a potential source for IDIC tolerance. In this study, 313 Oryza accessions were evaluated for IDIC tolerance at the tillering stage under aerobic conditions and twenty IDIC tolerant lines were identified. The twenty lines showed no signs of chlorosis and had high levels of iron content and SPAD values, while eight cultivated controls exhibited varying degrees of chlorosis symptoms and low levels of SPAD and iron content. To confirm their tolerance, the selected lines were evaluated again in a subsequent year, and they showed comparable levels of tolerance indicating these lines were efficient in iron uptake and utilization resulted maintained high chlorophyll and leaf area index. These accessions may be useful for developing IDIC-tolerant cultivars for aerobic rice cultivation and future study of molecular basis of IDIC tolerance.
ARTICLE | doi:10.20944/preprints202304.0023.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Arabidopsis; ER-bodies; aspartic proteinases; Plant Specific Insert; Vacuolar sorting; Endomembranes
Online: 3 April 2023 (10:36:29 CEST)
The endomembrane system in plant cells enables the cell to manage and coordinate a variety of membranous compartments so that they and their contents arrive at the right location. The secretory pathway takes part in this complex network and has its gateway at the Endoplasmic Reticulum. Therefore, alterations at the Endoplasmic reticulum level could condition how protein trafficking takes place or, at least, influence how such cargo leaves this organelle. With this work, we intended to assess how abnormalities at the Endoplasmic Reticulum would interfere with protein sorting and trafficking. Thus, we used a novel Arabidopsis mutant - leb-2 GFP-h -, presenting ER morphology alterations. Our results show that alterations in the leb-2 GFP-h mutant did not disrupt PSI A/B–mCherry transport to the vacuole but influences the expression of endogenous aspartic proteinases. Furthermore, the study of key-endomembrane genes expression revealed an upregulation of the SNAREs AtVAMP722 and AtVAMP723. As a whole, the leb-2 mutant seems not to interfere with vacuolar routes but may be implicated in secretion events.
ARTICLE | doi:10.20944/preprints202303.0481.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: genetic fidelity; genetic diversity; IRAP; ISSR; Rhododendron
Online: 28 March 2023 (09:56:04 CEST)
Rhododendron is well-known for the colorful corolla. Molecular marker systems have the potentials to elucidate genetic diversity as well as to assess the genetic fidelity in rhododendrons. In the present study, the reverse transcription domains of long terminal repeat retrotransposons were cloned from rhododendrons and used to develop inter-retrotransposon amplified polymorphism (IRAP) marker system. Subsequently, 198 polymorphic loci were generated from the IRAP and inter-simple sequence repeat (ISSR) markers, of which 119 were derived from the IRAP markers. It was justified that in rhododendrons, IRAP markers were superior to the ISSRs in some polymorphic parameters such as the average number of polymorphic loci (14.88 versus 13.17). In comparison with the single one, the combination of IRAPs and ISSRs systems was more discriminative for detecting 46 rhododendron accessions. Further, IRAP markers demonstrated more efficiency in genetic fidelity detection of in vitro R. bailiens, an endangered species just recorded in Guizhzhou Province, China. The available evidences revealed the distinct properties of IRAP and ISSR markers in the rhododendron-associated applications, and highlighted the availability of highly informative ISSR and IRAP markers in the genetic diversity evaluation and the genetic fidelity assessment of rhododendrons, which may facilitate the preservation and genetic breeding in rhododendron plants.
ARTICLE | doi:10.20944/preprints202202.0295.v2
Subject: Biology And Life Sciences, Plant Sciences Keywords: Alfalfa; bZIP transcription factor; phylogenetic analysis; expression pattern; abiotic stress
Online: 27 March 2023 (08:37:10 CEST)
Alfalfa (Medicago sativa L.) is the most cultivated forage legume around the world. Under a variety of growing conditions, forage yield in alfalfa is stymied by biotic and abiotic stresses including heat, salt, drought, and disease. Given the sessile nature of plants, they use strategies such as differential gene expression to respond to environmental cues. Transcription factors control the expression of genes that contribute to or enable tolerance and survival during periods of stress. Basic-leucine zipper (bZIP) transcription factors have been demonstrated to play a critical role in regulating plant growth and development as well as mediate the responses to abiotic stress in several species, including Arabidopsis thaliana, Oryza sativa, Lotus japonicus, and Medicago truncatula. However, there is little information about bZIP transcription factors in cultivated alfalfa. In the present study, 237 bZIP genes were identified in alfalfa from publicly available sequencing data. Multiple sequence alignments showed the presence of intact bZIP motifs in the identified sequences. Based on previous phylogenetic analyses in Arabidopsis thaliana, alfalfa bZIPs were similarly divided and fell into 10 groups. The physicochemical properties, motif analysis, and phylogenetic study of the alfalfa bZIPs revealed high specificity within groups. The differential expression of alfalfa bZIPs in a suite of tissues indicates that particular bZIP genes are specifically expressed at different developmental stages in alfalfa. Similarly, expression analysis in response to ABA, cold, drought, and salt stresses, indicates that a subset of bZIP genes are also differentially expressed and likely play a role in abiotic stress signaling and/or tolerance. These expression patterns were further verified by qRT-PCR. However, further functional characterization of bZIP transcription factors in alfalfa will help illuminate the role they play in stress tolerance mechanisms in legumes and facilitate the molecular breeding of stress tolerance in alfalfa.
ARTICLE | doi:10.20944/preprints202303.0382.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Microalgae; Monoraphidium sp.; Abiotic stress; Biomass; Carotenoids; Lipids
Online: 22 March 2023 (01:49:20 CET)
Carotenoids are essential pigments that play a vital role in the photosynthetic process of algae and are important for human health and nutrition. Despite their potential value, algal carotenoids are being neglected by biofuel industries. Recent research is aimed at producing microalgal lipids and carotenoids simultaneously under abiotic stresses. In this study, the effect of different abiotic stress factors such as Nitrogen (N), Potassium (K), Phosphorous (P), Sulphur (S), light intensity, and photoperiod on biomass, lipid, and carotenoids synthesis in Monoraphidium sp. (MP) were explored utilizing a statistical method. In addition, 2, 7-dichlorofluorescein diacetate (DCF-DA) mediated spectrofluorimetry was employed to detect the ele-vation in ROS level. The results revealed that variations in nutrients and light con-ditions are the key factors in the up-regulation of biomolecules lipids and carote-noids in the algae. The carotenoids profiling was done by Ultra Performance Liquid Chromatography Quadrupole Time-of-Flight Mass Spectroscopy (UPLC-Q-ToF-MS). Among consisting carotenoids violaxanthin, astaxanthin, and beta-carotene were enhanced by 1.3 folds, 1.19 folds, 1.08 folds, while lutein was declined by 1.32 folds under stressed condition compared to control. The identified carotenoids are rec-ognized for their importance in the pharmaceutical and nutraceutical industries, highlighting the significant role of MP in these sectors.
ARTICLE | doi:10.20944/preprints202303.0348.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: low-k dielectrics; organosilica glass; interconnects; photoluminescence; oxygen deficient centers
Online: 20 March 2023 (07:05:55 CET)
UV induced photoluminescence of organosilica films with ethylene and benzene bridging groups in their matrix and terminal methyl groups on the pore wall surface is studied to reveal optically active defects and understand their origin and nature. Careful selection of the film’s precursors and conditions of deposition and curing, analysis of chemical and structural properties led to the conclusion that luminescence sources are not associated with the presence of oxygen-deficient centers, as in the case in pure SiO2. It is shown that the sources of luminescence are the carbon-containing components that are part of the low-k-matrix, as well as the carbon residues formed upon removal of the template and UV induced destruction of organosilica samples. A good correlation between the energy of the photoluminescence peaks and the chemical composition is observed. This correlation is confirmed by the results obtained by the Density Functional theory. The photoluminescence intensity increases with porosity and internal surface area. The spectra become more complicated after annealing at 400 °C, although Fourier transform infrared spectroscopy does not show these changes. The appearance of additional bands is associated with compaction of low-k matrix and segregation of template residues on the surface of the pore wall.
ARTICLE | doi:10.20944/preprints202303.0280.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: transitional water ecosystems; coastal lagoons; biodiversity; typology; aquatic vegetation; abiotic factors; benthic communities; conservation; environmental variability
Online: 15 March 2023 (10:08:21 CET)
Coastal lagoons are dynamic transitional water ecosystems hosting valuable biological communities, including rich and diverse macrophyte assemblages. Aquatic macrophytes must cope with large fluctuations of environmental conditions on a spatial and seasonal scale. Salinity is one of the most variable parameters, changing from nearly freshwater to hypersalinity, and it is known to have a strong influence on the composition and structure of macrophyte assemblages. This study is focused on the effect of salinity on macrophyte communities of the eight most important coastal lagoons of Apulia (south-eastern Mediterranean Sea). A set of eleven transitional water body types (sensu Water Framework Directive) were allocated in a range of meso- to hyperhaline lagoons. Macrophyte sampling was carried out between 2011 and 2019 and a total of 324 samples (18 sampling stations x 2 seasons x 9 years) was analyzed. Then, macrophyte occurrence in each transitional water body (T-WB) was expressed as frequency values (%) and assemblages were compared to assess any similarity in relation to four salinity classes (mesohaline, polyhaline, euhaline, hyperhaline). Species richness varied according to the salinity class, being much higher in polyhaline and euhaline T-WBs and strongly decreasing at the extremes of salinity range (mesohaline and hyperhaline T-WBs). Moreover, statistical analysis showed a high resemblance of macrophyte assemblages of T-WBs within the same salinity class, which shared a great number of species. Four distinct macrophyte communities were distinguished, reflecting the salinity conditions of different T-WB types and confirming the effectiveness of a lagoon typology based on this descriptor.
ARTICLE | doi:10.20944/preprints202303.0274.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: elevated CO2; fluctuation; photosynthesis; stomatal conductance; photosystem II; cycling; fluorescence
Online: 15 March 2023 (08:57:01 CET)
Experimental systems to simulate future elevated CO2 conditions in the field often have large, rapid fluctuations in CO2. To examine possible impacts of such fluctuations on photosynthesis, intact leaves of field grown plants of five species were exposed to two-minute cycles of CO2 between 400 and 800 mol mol-1 lasting a total of 10 minutes, with photosynthesis, stomatal conductance and PSII fluorescence measured at the end of each half-cycle, and also 10 minutes after the end of the cycling. Prior to the cyclic CO2 treatments, steady-state responses of leaf gas exchange and fluorescence to CO2 were determined. In four of the five species, in which stomatal conductance decreased with increasing CO2, the cyclic CO2 treatments reduced stomatal conductance. In those species, both photosynthesis and the photochemical efficiency of PSII were reduced at limiting internal CO2 levels, but not at saturating CO2. In the fifth species, there was no change in stomatal conductance with CO2, and no change in either photosynthesis or PSII efficiency at any CO2 level with CO2 cycling. It is concluded that in many, but not all, species fluctuations in CO2 may reduce photosynthesis at low CO2 partly by decreasing the photochemical efficiency of photosystem II, as well as by decreasing stomatal conductance.
ARTICLE | doi:10.20944/preprints202303.0229.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: rice; variety; selection; mutagenesis; gamma rays; fast neutrons; salinity; drought tolerance
Online: 13 March 2023 (10:28:52 CET)
The article presents research results of the γ-ray and fast neutrons impact on various rice species, in order to obtain mutant forms resistant to salinity (NaCl) and drought factors (sorbitol. They are going to be used as initial forms in synthetic selection when creating varieties, adapted to the stressful conditions of, both, soil and climate in the Kazakhstan Aral Sea. The average lethal doses (LD50) of γ-rays and fast neutrons, as well as the average NaCl and sorbitol lethal concentrations were established. Such environment is best suited for clear manifestation of the mutagenic effect of ionizing radiation and the resistance of rice plants to salinity and drought. A distinct dependence in the effect of ionizing radiation and stress factors on the number of induced resistant mutant forms has been related to the initial rice sort. The largest number of mutant forms was obtained from the local variety Syr Suluy, followed by Leader and AyKerim varieties. From all varieties, the number of mutants obtained from exposure to γ-rays was 43 pieces out of 4500 grains, and from the impact of fast neutrons - 115 pieces out of 2700 grains. M1 mutant plants significantly differ from the initial forms in terms of morphological features – plant height, panicle length, grain size Most plants are characterized by short growth and even dwarfism (˂80 cm). They are lodging tolerant, have short and highly sterile panicles, indicating that they are mutants and resistant to salinity, drought, or both.
ARTICLE | doi:10.20944/preprints202303.0168.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: rhizosphere; phyllosphere; metagenomics; microbiome; nutrient cycling; metagenomic assembled-genomes (MAGs); nitrogen-fixation; nitrogen
Online: 9 March 2023 (06:30:48 CET)
Switchgrass (Panicum virgatum L.) remains the preeminent American perennial (C4) bioenergy crop for cellulosic ethanol that could help displace over a quarter of the US current petroleum consumption. Intriguingly, there is often little response to nitrogen fertilizer once stands are established. The rhizosphere microbiome plays a critical role in nitrogen cycling and overall plant nutrient uptake. We used high-throughput metagenomic sequencing to characterize the switchgrass rhizosphere microbial community (5.37 billion Illumina reads at 805 Gbp of data) before and after a nitrogen fertilization event for established stands on marginal land. We examined community structure, bulk metabolic potential, and resolved 29 individual bacteria genomes via metagenomic de novo assembly. Community structure and diversity were not significantly different before and after fertilization; however, the bulk metabolic potential of carbohydrate-active enzymes was depleted after fertilization. We resolved 29 metagenomic assembled genomes including some from the ‘most wanted’ soil taxa such as Verrucomicrobia, Candidate phyla UBA10199, Acidobacteria (rare subgroup 23), Dormibacterota, and the very rare Candidatus Eisenbacteria. The Dormibacterota (formally candidate division AD3) we identified have the potential for autotrophic CO utilization, which may impact carbon partitioning and storage. Our study also suggests that the rhizosphere microbiome may be involved in providing associative nitrogen fixation (ANF) via the novel diazotroph Janthinobacterium, which may partially explain why switchgrass growth is insensitive to fertilizer.
ARTICLE | doi:10.20944/preprints202302.0499.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Choy Sum; Penicillium citrinum; growth promotion; gibberellin; cytokinin; phytohormone
Online: 28 February 2023 (03:22:23 CET)
Soil-borne beneficial microbes establish symbioses with plant hosts, and play key roles during growth and development therein. In this study, two fungal strains, FLP7 and B9, were isolated from the rhizosphere microbiome associated with Choy Sum (Brassica rapa var. parachinensis) and barley (Hordeum vulgare), respectively. Sequence analyses of the internal transcribed spacer and 18S ribosomal RNA genes combined with colony and conidial morphology identified FLP7 and B9 to be Penicillium citrinum strains/isolates. Plant-fungus interaction assays revealed that isolate B9 showed significant growth promotion effects in Choy Sum plants cultivated in normal soil, as well as under phosphate-limiting conditions. In comparison to the mock control, B9-inoculated plants showed a 34% increase in growth in aerial parts, and an 85% upsurge in the fresh weight of roots when cultivated in sterilized soil. The dry biomass of such fungus-inoculated Choy Sum increased by 39% and 74% for the shoots and roots, respectively. Root colonization assays showed that P. citrinum associates directly with the root surface but does not enter or invade the root cortex of the inoculated Choy Sum plants. Preliminary results also indicated that P. citrinum can promote growth in Choy Sum via volatile metabolites too. Interestingly, we detected relatively higher amounts of gibberellins and cytokinins in axenic P. citrinum culture filtrates through liquid-chromatography mass-spectrometry analyses. This could plausibly explain the overall growth induction in P. citrinum-inoculated Choy Sum plants. Furthermore, the phenotypic growth defects associated with the Arabidopsis ga1 mutant could be chemically complemented by the exogenous application of P. citrinum culture filtrate, which also showed accumulation of fungus-derived active gibberellins. Our study underscores the importance of transkingdom beneficial effects of such mycobiome-assisted nutrient assimilation, and beneficial fungus-derived phytohormone-like metabolites in induction of robust growth in urban farmed crops.
ARTICLE | doi:10.20944/preprints202302.0407.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Calcium sensors; CBL; CIPK; Salt stress; Kinases; Cell signaling
Online: 23 February 2023 (09:44:44 CET)
Plants have acquired sets of highly regulated and complex signaling pathways to respond to unfavorable environmental conditions during evolution. Calcium signaling, as a vital mechanism, enables plants to respond to external stimuli, including abiotic and biotic stresses, and coordinate the basic processes of the growth and development. In the present study, the calcium sensor families, including CBL and CIPK, were investigated in the halophyte plant, Aeluropus littoralis, with a comprehensive analysis. Here, six AlCBL genes, and twenty AlCIPK genes were presented. The analysis of the gene structure and conserved motifs, as well as physicochemical properties, showed that these genes are highly conserved during evolution. The expression levels of AlCBL genes and AlCIPK genes were evaluated under salt stress in leaf and root tissue. Based on the real-time RT-PCR results, AlCIPK gene family had a higher variation in mRNA abundance compared to the AlCBL gene family. The AlCIPKs were found to have a higher abundance in leaves than in roots. The results suggest that the interaction pattern of AlCBL genes with AlCIPK is tissue-specific, and different interactions can be expected in leaves and roots. Based on these patterns AlCIPK3.1 - AlCBL4.1 and AlCIPK1.2 - AlCBL4.4 can interact in root tissue, while the AlCBL10 has the potential to interact with the AlCIPK5, AlCIPK26 and AlCIPK12.3 in the leaf tissue. These findings provide valuable information on the structure and function of calcium sensor families in Aeluropus littoralis a halophyte plant, for future research on the biological function of CBLs and CIPKs on salt stress resistance.
REVIEW | doi:10.20944/preprints202209.0152.v2
Subject: Biology And Life Sciences, Plant Sciences Keywords: Plant disease epidemics
Online: 23 February 2023 (02:56:41 CET)
A synoptic review of plant disease epidemics and outbreaks was made using two complementary approaches. The first approach involved reviewing scientific literature published in 2021, in which quantitative data related to new plant disease epidemics or outbreaks were obtained via surveys or similar methodologies. The second approach involved retrieving new records added in 2021 to the CABI Distribution Database, which contains over a million global geographic records of organisms from over 50,000 species. The literature review retrieved 186 articles, describing studies in 62 categories (pathogen species/species complexes) across >40 host species on 6 continents. Pathogen species with >5 articles were: Bursaphelenchus xylophilus, Candidatus Liberibacter asiaticus, cassava mosaic viruses, citrus tristeza virus, Erwinia amylovora, Fusarium spp. complexes, Fusarium oxysporum f. sp. cubense, Magnaporthe oryzae, maize lethal necrosis co-infecting viruses, Meloidogyne spp. complexes, Pseudomonas syringae pvs, Puccinia striiformis f. sp. tritici, Xylella fastidiosa, and Zymoseptoria tritici. Automated searches of the CABI Distribution Database identified 617 distribution records new in 2021 of 283 plant pathogens. A further manual review of these records confirmed 15 pathogens reported in new locations: apple hammerhead viroid, apple rubbery wood viruses, Aphelenchoides besseyi, Biscogniauxia mediterranea, Ca. Liberibacter asiaticus, citrus tristeza virus, Colletotrichum siamense, cucurbit chlorotic yellows virus, Erwinia rhapontici, Erysiphe corylacearum, Fusarium oxysporum f. sp. cubense Tropical Race 4, Globodera rostochiensis, Nothophoma quercina, potato spindle tuber viroid, and tomato brown rugose fruit virus. Of these, 4 pathogens had at least 25% of all records reported in 2021. We assessed two of these pathogens – tomato brown rugose fruit virus and cucurbit chlorotic yellows virus – to be actively emerging in/spreading to new locations. Although three important pathogens – Ca. Liberibacter asiaticus, citrus tristeza virus and Fusarium oxysporum f. sp. cubense – were represented in the results of both our literature review and our interrogation of the CABI Distribution Database, in general our dual approaches revealed distinct sets of plant disease outbreaks and new records, with little overlap.
REVIEW | doi:10.20944/preprints202301.0532.v2
Subject: Biology And Life Sciences, Plant Sciences Keywords: natural products; plant extracts; Myrtus communis; medicinal plants; antimicrobial; antioxidants; antiviral; biofilm inhibition
Online: 7 February 2023 (03:33:29 CET)
Myrtus communis L., commonly known as true myrtle, is a medicinal plant native to the Mediterranean area. Since ancient times inhabitants of this area have been using it for its cultural and medicinal properties. Due to the high content of essential oil in its flowers, leaves and fruits, M. communis is an important medicinal and aromatic species from Myrtaceae family. Because of the presence of vast diversity of biomolecules in its aerial parts, it exhibits several biological properties of antioxidant, antimicrobial and anticancer. There has been increasing scientific interest in the field to understand the pleotropic effects of its extracts or essential oils on various ailments and diseases. This purpose of this review is to summarizes the chemical composition, traditional uses, and biological activities of M. communis L. leaves documented in numerous recent studies.
ARTICLE | doi:10.20944/preprints202302.0087.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: intensive horticulture; bush habit; qualitative characteristics of berries; sintering and shedding of berries; yield; technologies; mechanized harvesting
Online: 6 February 2023 (08:37:14 CET)
The cultivation of berry crops by the type of "intensive plantings" is an economic and scientific approach in modern horticulture. The principles of forming a red currant assortment adapted to mechanized harvesting are considered. The bush should be compact for mechanized harvesting and have a straight-growing or slightly spreading shape. The morphological structure of the bush is a feature determined by the genotype. The ripening period of berries and the mechanical parameters of berries assess the effectiveness of the berry harvesting process. With the help of agrotechnical techniques, the mechanical parameters of berries cannot be improved and are de-termined by weather, soil, water, and climatic factors. The present study was conducted in the 2021-2022 season using 14 red currant genotypes of different geographical and genetic origins to assess cultivars' suitability for machine harvesting. In most of the studied cultivars, berry quality indicators, the parameters of separation force (Fs) and crushing force (Fc) decreased by the time of biological maturity of the genotype. Several cultivars have shown a non-simultaneous decrease in Fs and Fc. A minor limiting feature determines the duration of harvesting. The high correlation of Fs and Fc (R=0.75-0.85) allows us to predict the most significant period for the high-quality operation of a mechanized harvester. There was no dependence of the strength of the attachment of berries to the peduncle on the thickness of the skin of the berries. Jonkheer Van Tets, Red Lake, Rovada, Rolan, Vika, Asya, and Niva can be attributed to technological cultivars as sources of compact and erect bush habit, Jonkheer Van Tets, Rovada, Rolan, Vika, and Asya are recommended for mechanized harvesting.
ARTICLE | doi:10.20944/preprints202301.0422.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Biological control; fitness attributes; glyphosate; Herbicide; insect; integrated weed management; Parthenium; Zygogramma bicolorata; weed
Online: 24 January 2023 (03:31:54 CET)
The ecotoxic effect of glyphosate, a commonly used Parthenium control herbicide, was evaluated in laboratory on biological and fitness attributes of Zygogramma bicolorata. Bioassay of glyphosate was carried within a minimum range of field recommended dose. Indirect exposure experiment reveals that glyphosate caused maximum mortality of 3rd larval instars, extends the development stages of larvae, pre pupation and pupation. Significant negative effect was observed on sex ratio, fecundity, egg viability and on other fitness attributes. The study demonstrated the non-compatibility of glyphosate and unsafe with Zygogramma bicolorata. The study concludes that owing to acute toxicity of glyphosate at recommended field dose may be used in combination with Z. bicolorata for successful control of Parthenium weed, but needs to be evaluated under natural field conditions.
ARTICLE | doi:10.20944/preprints202301.0366.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Encephalartos natalensis; microbe-symbiosis; soil nutrition; enzyme activities; soil nutrient cycling
Online: 19 January 2023 (15:29:52 CET)
Encephalartos spp. establish symbioses with nitrogen (N)-fixing bacteria that contribute to soil nutrition and improve plant growth. Despite the Encephalartos mutualistic symbioses with N-fixing bacteria, the identity of other bacteria and their contribution to soil fertility and eco-system functioning are not well understood. This limited information presents a challenge in developing comprehensive conservation and management strategies for these cycad species. Therefore, this study identified the nutrient cycling bacteria in Encephalartos natalensis coral-loid roots, rhizosphere, and non-rhizosphere soils. Additionally, the soil characteristics and soil enzyme activities of the rhizosphere and non-rhizosphere soils were assayed. The coral-loid roots, rhizosphere, and non-rhizosphere soils of E. natalensis were collected from a popu-lation of >500 E. natalensis in a disturbed savanna woodland at Edendale in KwaZulu-Natal (South Africa) for nutrient analysis, bacterial identification, and enzyme activity assays. Nu-trient cycling bacteria such as Lysinibacillus xylanilyticus; Paraburkholderia sabiae, and Novo-sphingobium barchaimii were identified in the coralloid roots, rhizosphere, and non-rhizosphere soils of E. natalensis. Phosphorus (P) cycling (alkaline and acid phosphatase) and N cycling (β-(D)-Glucosaminidase and nitrate reductase) enzyme activities showed a pos-itive correlation with the P and N concentrations in the rhizosphere and non-rhizosphere soils of E. natalensis. Nutrient cycling bacteria identified in E. natalensis coralloid roots, rhizo-sphere, and non-rhizosphere soils and associated enzymes assayed may contribute to soil nu-trient inputs of E. natalensis plants growing in acidic and nutrient-poor savanna woodland ecosystems.
ARTICLE | doi:10.20944/preprints202301.0182.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Sugars; metabolism; yam; tuber; genotypes; dormancy; regulation
Online: 10 January 2023 (10:24:48 CET)
Abstract: Changes in sugar composition occur continuously in plants tissues, at different develop-mental stages. Tuber dormancy induction, stability, and breaking are very critical developmental transitions in yam crop production. Prolonged tuber dormancy after physiological maturity has constituted a great challenge in yam genetic improvement and productivity. In the present study, biochemical profiling of non-structural sugar in yam tuber during dormancy was performed to determine the role of non-structural sugar in yam tuber dormancy regulation. Two genotypes of white yam specie; one local genotype (Obiaoturugo) and (TDr1100873) were used for this study. Tubers were sampled at (42, 56, 87, 101, 115, and 143) days after physiological maturity (DAPM). Obiaoturugo exhibited a short dormant phenotype and sprouted at 101DAPM, whereas TDr1100873 exhibited a long-dormant phenotype, and sprouted at 143DAPM. Significant metabolic changes were observed in non-structural sugar parameters, dry matter, and moisture content in Obiaoturugo from 56DAPM, whereas, in TDr1100873 significant metabolic changes were observed from 101DAPM. It was observed that the onset of these metabolic changes occurred at a point when the tubers of both genotypes exhibited dry matter content of 60%, indicating that dry matter content of 60% might be a critical threshold for white yam tuber sprouting. Nonreducing sugars increased by 9-10-fold during sprouting in both genotypes which indicates its key role in tuber dormancy regulation in white yam. This result implies that some key sugar metabolites can be targeted for dormancy manipulation of yam crop.
ARTICLE | doi:10.20944/preprints202301.0117.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Temporary Immersion Bioreactor; Micropropagation; Plantain; plant tissue culture
Online: 6 January 2023 (06:26:15 CET)
The genus Musa spp. contains commercially important fleshy fruit producing plants including plantains and bananas with a strong potential of providing food security and source of revenue to farmers. Occasionally, plantlets are often not available to fulfill the supply demand of farmers particularly in Caribbean region. Concerns with the quality of vegetative tissues along with the possibility of the transmission of phytopathogens makes availability of plantlets limited to farm-ers. Micropropagation of plantains offers an alternative to producing large number of in-vitro plantlets. However, conventional methods of micropropagation techniques require high produc-tion costs and are labor-intensive. Recently, Temporary Immersion Bioreactor (TIB) has emerged as an alternative to conventional micropropagation methods. Our work utilized SEM (Scanning Electron Microscope), molecular and biochemical tools (qRT-PCR and ICP-OES) to characterize and compare the morphological, elemental composition, and photosynthetic gene expression of plantains cultured on TIB. Additionally, morphological features of growth and propagation rates were analyzed for comparing outputs obtained from temporary immersion bioreactor with conventional micropropagation (CM) techniques. Results showed higher growth and multiplication rates for plantlets cultivated in TIB. Gene expression analysis of selected photosynthetic genes demonstrated high transcript abundance of phosphoenol pyruvate carboxylase (PEPC) in plantain tissues obtained by TIB. Elemental composition analysis showed higher content of iron in plantains grown in TIB suggesting a potential correlation with PEPC expression. These results demonstrate the potential of TIB to be an efficient method to produce healthy in-vitro plantains.
ARTICLE | doi:10.20944/preprints202301.0097.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: mitochondria; iron transporters; MIT; developmental defects; RNA-seq
Online: 5 January 2023 (03:42:32 CET)
Iron is the most abundant micronutrient in plant mitochondria and it has a crucial role in biochemical reactions involving electron transfer. It has been described in Oryza sativa that Mitochondrial Iron Transporter (MIT) is an essential gene and that knockdown mutant rice plants have a decreased amount of iron in mitochondria, strongly suggesting that OsMIT is involved in mitochondrial iron uptake. In Arabidopsis thaliana, two genes encode MIT homologues. In this study, we analyzed different AtMIT1 and AtMIT2 mutant alleles, confirming that individually AtMIT1 nor AtMIT2 genes are essential. When we generated crosses between Atmit1 and Atmit2 alleles we were able to isolate homozygous double mutant plants. Interestingly, homozygous double mutant plants were obtained only when mutant alleles of Atmit2 with the T-DNA insertion in the intron region were used for crossings, and in these cases a correctly spliced AtMIT2 mRNA was generated, although at a low level. Atmit1 Atmit2 double homozygous mutant plants, which were knockout for AtMIT1 and knockdown for AtMIT2, were grown and chacterised in iron sufficient conditions. Pleiotropic developmental defects were observed including abnormal seeds, increased number of cotyledons, slow growth rate, pinoid stems, defects in flower structures and reduced seed set. We observed a possible phenomenon of T-DNA suppression in the next generation of Atmit1 Atmit2 double homozygous mutant plants, correlating with an increased splicing of the AtMIT2 intron containing the T-DNA. Molecular analysis of gene expression markers for mitochondrial and oxidative stress showed that Atmit1 Atmit2 double homozygous mutant plants express a degree of mitochondrial perturbation. A RNA-Seq study was performed and we could identify more than 760 genes differentially expressed in Atmit1 Atmit2, including genes involved in iron transport, coumarin metabolism, and hormones metabolism, transport and signaling. Our data suggest that some of the phenotypes observed in Atmit1 Atmit2 double homozygous mutant plants are mediated by defects in auxin homeostasis.
REVIEW | doi:10.20944/preprints202301.0028.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: indole-3-acetic acid; abscisic acid; plant hormones; crosstalk; signaling
Online: 3 January 2023 (09:36:32 CET)
Plants are constantly exposed to a variety of different environmental stresses, including drought, salinity, and elevated temperatures. These stress cues are assumed to aggravate in the future driven by the global climate change scenario which we are currently experiencing. These stressors have largely detrimental effects on plant growth and development and, therefore, put global food security in jeopardy. For this reason, it is necessary to expand our understanding of the underlying mechanisms by which plants respond to abiotic stresses. Especially boosting our insight into the ways by which plants balance their growth and their defense programs appears to be of paramount importance, as this may lead to novel perspectives that can pave the way to increase agricultural productivity in a sustainable manner. In this review, our aim was to present a detailed overview of different factettes of the crosstalk between the antagonistic plant hormones abscisic acid (ABA) and auxin, two phytohormones that are the main drivers of plant stress responses, on the one hand, and plant growth, on the other.
ARTICLE | doi:10.20944/preprints202212.0506.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Senecio; Jacoboea; Orbitrap; chemophenetic; clustering; R
Online: 27 December 2022 (03:16:47 CET)
Herein, a chemophenetic significance, based on phenolic metabolite profiling of three Senecio (S. hercynicus, S. ovatus and S. rupestris) and two Jacobaea species (J. pancicii and J. maritima) coupled to morphometric data, is presented. A set of twelve morphometric characters were recorded from each plant species and used as predictor variables in a Linear Discriminant Analysis (LDA) model. From a total 75 observations (15 from each of the five species), the model correctly assumed their species' membership, except 2 observations. Among the studied species, S. hercynicus and S. ovatus presented the greatest morphological similarity. A phytochemical profiling of phenolic specialized metabolites by UHPLC-Orbitrap-HRMS revealed 46 hydroxybenzoic, hydroxycinnamic, acylquinic acids and their derivatives, 1 coumarin, and 21 flavonoids. Hierarchical and PCA clustering applied to the phytochemical data corroborated the similarity of S. hercynicus and S. ovatus, observed in the morphometric analysis. This study contributes to the phylogenetic relationships between the tribe Senecioneae taxa and highlights the chemophenetic similarity/dissmilarity of the studied species belonging to Senecio and Jacobaea genera.
REVIEW | doi:10.20944/preprints202212.0411.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: chemical herbicides; phytotoxin; natural compounds; biorational herbicides; screening; formula-tions; synthesis; mechanisms of action
Online: 22 December 2022 (03:18:18 CET)
Weeds are a permanent component of anthropogenic ecosystems, which requires strict control to avoid the accumulation of their long–lasting seeds in the soil. With high crop infestation, many elements of crop production technologies (fertilization, productive varieties, growth stimulators, etc.) turn out to be practically meaningless due to high yield losses. Intensive use of chemical herbicides (CH) has led to undesirable consequences: contamination of soil and wastewater, accumulation of their residues in the crop, the emergence of CH-resistant populations of weeds. In this regard, the development of environmentally friendly CH with new mechanisms of action is relevant. Natural phytotoxins of plant or microbial origin may be directly explored in herbicidal formulations (biorational CH) or indirectly as scaffolds for nature-derived CH. This review considers: 1) the main current trends in the development of CH that may be important for enhancement of biorational herbicides; 2) advances in the development and practical application of natural compounds for weed control; 3) the use of phytotoxins as prototypes of synthetic herbicides. Some modern approaches such as computational methods of virtual screening and design herbicidal molecules, development of modern formulations, determination of molecular targets are stressed as important to make exploration of natural compounds more effective.
ARTICLE | doi:10.20944/preprints202212.0281.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Water channel; Abiotic stresses; Wheat genes; Post-translation modification; Gene expression
Online: 15 December 2022 (10:07:52 CET)
During the response of plants to adverse stresses, aquaporin (AQP) plays a prominent role in membrane water transport based on received upstream signals. In addition, they have various physical parts for dealing with environmental stresses. Due to the importance of the AQP gene family, studies have been conducted investigating the function and regulatory system of these genes. However, many of their molecular aspects are still unknown. This study aims to carry out a genomic-wide investigation of the AQP gene family in durum wheat using bioinformatics tools and to investigate the expression patterns of some members in response to salt stress. Our results showed that there are 80 TtAQP genes in durum wheat, which are classified into four main groups based on phylogenetic analysis. Many duplications were observed between the members of the TtAQP gene family, and high diversity in response to post-translational modifications was observed between TtAQP family members. The expression pattern of TtAQP genes disclosed that these genes are primarily upregulated in response to salt stress. Besides, qPCR data revealed that TtAQPs are more induced in delayed responses to salinity stress. Overall, our findings illustrate that TtAQP members are diverse in terms of their structure, regulatory systems and expression levels.
REVIEW | doi:10.20944/preprints202212.0272.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Apiaceae plant; Traditional use; Phytochemistry; Bolting and flowering; Controlling approach; Lignification
Online: 15 December 2022 (07:18:54 CET)
Ethnopharmacological relevance: Apiaceae plants have been widely used as traditional Chinese medicines (TCMs) for the treatment of removing dampness to relieve pain, relaxing tendons, and activating blood, as well as relieving superficies and dispelling cold. Aim of the review: This review aims to summarize the traditional use, phytochemistry, and modern pharmacological use of Apiaceae medicinal plants (AMPs), highlight the effect of bolting and flowering (BF) on yield and quality, and provide a basis for controlling the BF. Materials and methods: All literatures involved in AMPs were searched using various online databases (e.g., PubMed, Web of science, Google Scholar, Springer, and CNKI). Additional information was collected from ethnobotanical literature focusing on herbs from Flora of China and local herbal classic literature. Result: A total of 228 AMPs have been recorded to be used as TCMs, with 6 medicinal parts (i.e., the whole plants, rhizomes and/or roots, stems, leaves, fruits, and seeds) categorized, 72 traditional uses (e.g., relieving pain, dispelling wind, and eliminating dampness) enriched, 62 modern pharmacological uses (e.g., anti-inflammatory, antioxidative, and antitumor activities) enriched, and 5 main kinds of metabolites (i.e., polysaccharides, alkaloids, phenylpropanoids, flavonoids, and terpenoids) categorized. Based on the influence level of BF on the yield and quality, 38 rhizomatous AMPs are categorized into 3 classes including: significantly affected, differently affected to some extent, and no significantly affected. Although the mechanism of BF inducing the rhizome lignification has been revealed to some extent, and several attempts have been made to control the BF, especially in Angelica sinensis, the problem of BF has not been solved in the practical production. Conclusions: So far, the traditional use of the 228 AMPs has been recorded, while the phytochemistry and modern pharmacological researches are still limited, thus, it is a treasure to find out new therapeutic agents. Since the BF regulated by internal factors and external factors have been demonstrated, and several key genes involved in BF have been identified, thus, it is available to control the BF by planting with standard techniques and innovating new cultivars using the CRISPR/Cas9 gene editing system. This review will provide useful references for the exploration and utilization, as well as the improvement of yield and quality of AMPs.
ARTICLE | doi:10.20944/preprints202212.0185.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Salix; shrub willow; genome assembly; sex determination
Online: 12 December 2022 (01:46:15 CET)
Poplar and willow species in the Salicaceae are dioecious, yet have been shown to use different sex determination systems located on different chromosomes. Willows in the section Vetrix are interesting for comparative studies of sex determination systems, yet genomic resources for these species are still quite limited. Only a few annotated reference genome assemblies are available, despite many species in use in breeding programs. Here we present de novo assemblies and annotations of 11 shrub willow genomes from six species. Copy number variation of candidate sex determination genes within each genome was characterized and revealed remarkable differences in putative master regulator gene duplication and deletion. We also analyzed copy number and expression of candidate genes involved in floral secondary metabolism, and identified substantial variation across genotypes, which can be used for parental selection in breeding programs. Lastly, we report on a genotype that produces only female descendants and identified gene presence/absence variation in the mitochondrial genome that may be responsible for this unusual inheritance.
REVIEW | doi:10.20944/preprints202212.0184.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: CRISPR; genome editing; gene editing; forage grass; abiotic stress; plant
Online: 12 December 2022 (01:38:47 CET)
Due to an increase in the consumption of food, feed, and fuel and to meet global food security needs for the rapidly growing human population, there is a necessity to obtain high-yielding crops that can adapt to future climate changes. Currently, the main feed source used for ruminant livestock production is forage grasses. In temperate climate zones, perennial grasses grown for feed are widely distributed and tend to suffer under unfavorable environmental conditions. Gene editing has been shown to be an effective tool for the development of abiotic stress-resistant plants. The highly versatile CRISPR-Cas system enables increasingly complex modifications in genomes while maintaining precision and low off-target frequency mutations. In this review, we provide an overview of forage grass species that have been subjected to gene editing. We offer a perspective view on the generation of plants resilient to abiotic stresses. Due to the broad factors contributing to these stresses the review focuses on drought, salt, heat, and cold stresses. The application of new genomic techniques (e.g., CRISPR-Cas) allows addressing several challenges caused by climate change and abiotic stresses for developing forage grass cultivars with improved adaptation to the future climatic conditions. Gene editing will contribute towards developing safe and sustainable food systems.
ARTICLE | doi:10.20944/preprints202211.0481.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Cynodon dactylon; Aspergillus flavus; endophytic fungus; secondary metabolites; anticancer; breast cancer; Bcl-2
Online: 25 November 2022 (10:19:48 CET)
Endophytic fungi are a diverse group of microorganisms that colonize the inter- or intracellular spaces of plants for mutual benefits. The interactions with a host plant and other microbiomes are multidimensional and play a crucial role in the production of secondary metabolites. We screened bioactive compounds present in the extracts of Aspergillus flavus, an endophytic fungus isolated from the roots of the medicinal grass Cynodon dactylon, for its anticancer potential. Ethyl acetate extract from isolated A. flavus showed significant cytostatic effects (IC50: 16.25 μg mL−1) against breast cancer cells (MCF-7). Morphology of cells and DAPI stained nuclei along with the results of flow cytometry annexin V/PI assay suggested apoptosis to be the main process leading to cells’ death. While investigating the mechanism that triggers apoptosis, we found that the extract of A. flavus increased ROS generation and caused loss of mitochondrial membrane potential of MCF-7 cells. To identify the metabolites that might be responsible for the anticancer effect, the extract was examined using gas chromatography-mass spectrometry (GC-MS). Interestingly, nine phytochemicals were found to have potential inhibitory effects of anti-apoptotic protein (Bcl-2) in the breast cancer cells. In the in silico molecular docking and molecular dynamics simulation studies revealed that two compounds: 2,4,7-Trinitrofluorenone and 3alpha, 5alpha-Cyclo-ergosta-7,9(11),22t-triene-6beta-ol exhibited significant binding affinities (-9.20, and -9.50 Kcal mol-1, respectively) against Bcl-2 along with binding stability and intermolecular interactions of its ligand-Bcl-2 complexes. Overall, the study found that the endophytic A. flavus from C. dactylon contains plant-like bioactive compounds that have a promising effect in breast cancer.
ARTICLE | doi:10.20944/preprints202211.0408.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: abiotic variables; altitude; immobilization; mineralization; mixed oak-pine forest
Online: 22 November 2022 (07:04:44 CET)
This study assessed the periodic ﬂuctuations among microbial biomass Carbon (C), Nitrogen (N) and Phosphorus (P), and the consequences of variations in altitude and abiotic factors on the soil microbial biomass (C, N and P) in a temperate mixed-oak pine forest of Central Himalaya. This research was directed at three forest stands along an altitudinal gradient. Samples were collected in triplicates, seasonally from each selected site and microbial C, N and P were determined through the fumigation extraction method. Microbial biomass C, N and P decreased significantly (P<0.01, correlation coefficient -0.985, -0.963, -0.948, respectively) with increasing altitude, while the rainy season showed the highest values, and winter season revealed the least values. Microbial biomass C, N and P showed positive correlation with silt particles, water holding capacity, bulk density, porosity, soil moisture, organic C, total N and P, and negative correlations with sand particles and soil pH. The microbial biomass C showed strong associations with soil microbial N (r=0.80, P<0.01) and P (r=0.89, P<0.01) contents, while the soil microbial biomass N and P also showed strong positive correlation (r=0.92, P< 0.01). Soil microbial biomass was greatly inﬂuenced by the altitude and abiotic variables whereas, weakly by temporal variation. The microbial C: N ratio indicated that fertility of soil is inﬂuenced by the species assemblage. Our findings suggest that high microbial biomass and low C: N ratio during rainy season could be considered as a strategy to conserve nutrients by temperate mixed-oak pine forest ecosystem.
ARTICLE | doi:10.20944/preprints202211.0199.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: cyanobacteria; photosystem; fast fluorescence kinetics; optical microcavity; fluorescence microscopy
Online: 10 November 2022 (11:05:24 CET)
Photosynthesis is one the most important biological processes on earth, producing life-giving oxygen and is the basis for a large variety of plant products. Measurable properties of photosynthesis provide information about its biophysical state and, in turn, the physiological conditions of a photoautotrophic organism. For instance, chlorophyll fluorescence of an intact photosystem is not linear as in the case of a single fluorescent dye in solution, but shows temporal changes related to the quantum yield of the photosystem. Commercial photosystem analyzers already use the fluorescence kinetics characteristics of photosystems to infer the viability of organisms under investigation. Here, we provide a novel approach based on an optical Fabry-Pérot microcavity or that enables the readout of photosynthetic properties and activity for an individual cyanobacterium. This approach offers a completely new dimension of information, which would normally be lost due to averaging in ensemble measurements obtained from a large population of bacteria.
ARTICLE | doi:10.20944/preprints202211.0173.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: aconitate hydratase; CRISPR/Cas9; male sterility; seedless tomato
Online: 9 November 2022 (10:01:29 CET)
Tomato (Solanum lycopersicum) is one of the most cultivated vegetables in the world due to its consumption in a large variety of raw, cooked, or processed foods. Tomato breeding and productivity highly depend on the use of hybrid seeds and their higher yield, environmental adaption, and disease tolerance. However, the emasculation procedure during hybridization raises tomato seed production costs and labor expenses. Using male sterility is an effective way to reduce the cost of hybrid seeds and ensure cultivar purity. Recent developments in CRISPR genome editing technology enabled tomato breeders to investigate the male sterility genes and to develop male-sterile tomato lines. In the current study, the tomato Acotinase (SlACO) gene family was investigated via in-silico tools and functionally characterized with CRISPR/Cas9-mediated gene disruption. Genome-wide blast and HMM search represented two SlACO genes located on different tomato chromosomes. Both genes were estimated to have a segmental duplication in the tomato genome due to their identical motif and domain structure. One of these genes, SlACO2, showed a high expression profile in all generative cells of tomato. Therefore, the SlACO2 gene was targeted with two different gRNA/Cas9 construct to identify their functional role in tomato. The gene was mutated in a total of 6 genome-edited tomato lines, 2 of which were homozygous. Surprisingly, pollen viability was found to be extremely low in mutant plants compared to their wild-type (WT) counterparts. Likewise, the number of seeds per fruit also sharply decreased more than fivefold in mutant lines (10-12 seed) compared to that in WT (67 seed). The pollen shape, anther structures, and flower colors/shapes were not significantly varied between the mutant and WT tomatoes. The mutated lines were also subjected to salt and mannitol-mediated drought stress to test the effect of SlACO2 on abiotic stress tolerance. The results of the study indicated that mutant tomatoes have higher tolerance with significantly lower MDA content under stress conditions. This is the first CRISPR-mediated characterization of ACO genes on pollen viability, seed formation, and abiotic stress tolerance in tomato.
ARTICLE | doi:10.20944/preprints202211.0156.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Anaerobic Preservation; Dendrochronology; Peatland Archives; Pine Decline; Pinus sylvestris L.; Radiocarbon (14C) Dating
Online: 8 November 2022 (11:56:28 CET)
A dendrochronological investigation was undertaken on subfossil Scots pine (Pinus sylvestris L.) stumps following their discovered during conservation management activities at Wem Moss, a small (28ha) former raised mire in Shropshire, UK. Two ring-width chronologies were constructed from 14 of the 17 trees investigated spanning 198 and 208 years respectively. Whilst absolute dating was not possible, radiocarbon assays provided an estimated age for this mire-rooting woodland of between 3015 – 2505 years Cal BC, coinciding with the age traditionally associated with the widespread mortality of pine trees throughout much of the UK and Ireland, The Pine Decline (circa 4 ka radiocarbon years BP). Placed in a wider geographical context, the Wem Moss pines are located within the wider lowland area of the Meres and Mosses Region, where previous studies on subfossil pine have demonstrated protracted declines in mire-rooting trees. These have included tree mortality significantly post-dating The Pine Decline, notably at larger peatland sites exceeding 5.5 km2. This macrofossil evidence for the presence of Scots pine into the late Holocene is supported by continuous Pinus pollen representation at peatland sites in the Welsh Marches (English-Welsh border) suggesting the possible survival of native Scots pine trees in this area up to the present-day. This research highlights the incomplete and patchy nature of palaeo-vegetational records and also the potential for genetic research on living Scots pine in possible refugial areas in the UK and Ireland.
ARTICLE | doi:10.20944/preprints202211.0145.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Mucuna seed; L-Dopa content; Lyophilized extract; Sugars identification; TLC; Mass spectrometry
Online: 8 November 2022 (03:31:47 CET)
Human societies demand sustainable alternatives for goods and services. Plants are sustainable sources of important metabolites with beneficial impacts on human health. There are many reported methodologies and commercial suppliers for extract preparations from the plant Mucuna sp. They usually claim to be enriched in L-dopa, their distinctive metabolite. However, there are poor characterizations of the metabolite's components in that extracts. Here, we present the metabolite characterization of a Mucuna seed extract, emphasizing the L-dopa identification and quantification. To obtain the extracts, we follow a green and sustainable extraction protocol. The lyophilized extract was subject to liquid chromatography and mass spectrometry to identify its primary metabolites. Additionally, we follow thin-layer chromatography to identify some carbohydrates in the sample. The resultant extract has a 56% L-dopa. Other main components in the extract were arginine, stizolamine, and the fructooligosaccharides sucrose and nystose. The characterized Mucuna extract can be easily standardized as powder presentation and used in several biomedical applications.
ARTICLE | doi:10.20944/preprints202210.0165.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: aerobic rice; high temperature; water limitation; yield component; seed quality; amylose content
Online: 12 October 2022 (07:28:25 CEST)
Drought and high temperature often occur simultaneously will eventually affect rice (Oryza sativa L.) yield and seed quality. The objective of the study was to compare the effects of high temperature (HT) and water limitation (WL) during seed development and maturation on yield component, seed quality, and amylose content in aerobic rice cv. MRIA. Two experiments were conducted concurrently in greenhouse with ⁓35/26℃ subjected to elevated HT and/or WL; 5 days 38/28°C at 10, 15, 29 DAA and/or HT; 7 days at 40/28℃ at 8 and 21 DAA with 12h photoperiod in control environment growth chamber. Both experiments were respectively harvested at physiological maturity of 31 and 35 DAA. Grain yielded from the irrigated plant declined from over 27% to below 18% between 15 and 29 DAA. Combination stresses resulted in greater reduction of grain yield than single stress. Late seed development (29 DAA) had no effect either on yield component or seed quality as well as produce a high concentration in amylase content (16.7%) with greater germination capacity (91%). The non-stress plant harvested at 21 DAA resulted the highest percentage of germinated seeds (97%) whereas the vigour index (VI) was reduced to 70.3% and 58.9% at 8 and 21 DAA respectively. Extended plant stress to 7 consecutive days incurred the highest VI with low concentration of amylose content. There was a linear relationship incurred between seed amylase content with germination capacity and VI, however, there was an inverse relationship (R2 = 0.19) between amylase content with VI from plant treated with (HT and/or WL) for 7 days. The present results confirmed that the avoidance HT and WL during early (10 DAA) and mid (15 DAA) seed development with short duration of stress (5 days) obtained better in yield component, enhanced the seed quality and amylose concentration. The combined HT and WL damaged seeds’ quality were more than each stress alone. Therefore, avoiding HT and WL can be practically applied by farmers by irrigating throughout the rice plant during histodifferentiation to save water usage during seed maturation.
ARTICLE | doi:10.20944/preprints202210.0106.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: within-plant phenotypic plasticity; combined stresses; additive, antagonistic and synergic effects; VOC
Online: 9 October 2022 (03:56:12 CEST)
Background: Drought, N deficiency and herbivory are considered the most important stressors caused by climate change in the agro- and eco-systems and varied in space and time shaping a highly dynamic and heterogeneous stressful environments. This study aims to evaluate the to-mato morpho-physiological and metabolic responses to combined abiotic and herbivory at dif-ferent within-plant spatial levels and temporal scales. Methods: Leaf-level morphological, gas exchange traits and VOC profiles were measured in to-mato plants exposed to N deficiency and drought, T. absoluta larvae and their combination. Ad-ditive, synergistic or antagonistic effects of the single stress when combined were also evaluat-ed. Morpho-physiological traits and VOC profile were also measured on leaves located at three different positions along the shoot axes. Results: The combination of the abiotic and biotic stress has been more harmful than single stress with antagonistic and synergistic but non-additive effects for the morpho-physiological and VOC tomato responses, respectively. Combined stress also determined a high within-plant phenotypic plasticity of the morpho-physiological responses. Conclusions: These results suggest that the combined stress in tomato determined a “new stress state” and a higher within-plant phenotypic plasticity which could permit an efficient use of the growth and defence resources in the heterogeneous and multiple stressful environmental condi-tions.
ARTICLE | doi:10.20944/preprints202210.0048.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Lead; Field trial; Phytostabilization; Phytomanagement; Aromatic plants; Bacterial community
Online: 5 October 2022 (17:51:14 CEST)
This field study aimed to assess the base line conditions of a long-term polluted shooting range in Argentina polluted with 428 mg kg-1 lead (Pb), to evaluate the establishment and development of Helianthus petiolaris plants and address the efficacy of the phytomanagement strategy through: i) element accumulation in plant tissues; ii) rhizosphere bacterial diversity changes by Illumina Miseq™ and iii) floral water and essential oil yield, composition and element concentration by GC-MS and ICP. After one life cycle growing in the polluted sites, in the roots of Helianthus petiolaris plants Pb concentration was between 195 and 304 mg kg-1 Pb. Only a limited fraction of the Pb was translocated to the aerial parts. The predominance of the genus Serratia in the rhizosphere of Helianthus petiolaris plants cultivated in the polluted sites and the decrees of the essential oil yield were some effects significantly associated with soil Pb concentration. No detectable Pb concentration was found in the floral water and essential oil obtained. Extractable Pb concentration in the soil reduced between 28-45 % after the harvest.
COMMUNICATION | doi:10.20944/preprints202209.0301.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Warrior (-) race; stripe rust; GWAS; Yr29/Lr46 gene; European wheat; SNP marker
Online: 20 September 2022 (09:58:25 CEST)
To evaluate genetic variability and seedling plant response to a dominated Warrior (-) race of yellow rust in Northern and Central European germplasm, we used a population of 229 winter wheat cultivars and breeding lines for genome-wide association study (GWAS). A wide variation in yellow rust disease severity (based on infection types 1-9) was observed in this panel. Four breeding lines TS049 (from Austria), TS111, TS185, and TS229 (from Germany) and one cultivar TS158 (KWS Talent) from Germany were found to be resistant to Warrior (-) FS 53/20 and Warrior (-) G 23/19. GWAS identified five significant SNPs associated with yellow rust on chromosomes 1B, 2A, 5B, and 7A for Warrior (-) FS 53/20, while one SNP on chromosome 5B was associated with disease for Warrior (-) G 23/19. For Warrior (-) FS 53/20, we discovered a new QTL for yellow rust resistance associated with the marker Kukri_c5357_323 on chromosome 1B. The resistant allele G at the marker locus Kukri_c5357_323 on chromosome 1B and the susceptible allele T at the marker locus Excalibur_c17489_804 on chromosome 5B showed the largest effects (1.21 and 0.81, respectively) on the severity of yellow rust detected in Warrior (-) FS 53/20 and Warrior (-) G 23/19. Among 144 putative genes within the flanking sequence of the significant SNPs detected by GWAS, the function of the best candidate genes was determined as protein kinase activity and oxidoreductase activity. Our results provide the basis for knowledge-based resistance breeding in the face of the enormous impact of the Warrior (-) race on wheat production in Europe.
ARTICLE | doi:10.20944/preprints202209.0272.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Pruning frequency; Sesbania sesban; 15N Natural abundance; N2 fixation; Ndfa
Online: 19 September 2022 (09:34:48 CEST)
Tree pruning is a management tool in agroforestry systems for reducing shade, enhancing nutrient cycling or providing fodder. However, little information is available on the effect of pruning management on plant growth, non-structural carbohydrate (NSC) levels in the roots and N2 fixation of Sesbania sesban. A glasshouse experiment was conducted to assess the effect of pruning frequency on biomass production, NSC levels and N2 fixation of Sesbania sesban. Treatments included pruning at (i) 3 months only, (ii) 3 and 6 months, and (iii) 3, 6 and 9 months, with each pruning removing shoot biomass above 50% of the initial height. Increased pruning frequency decreased above- and belowground dry matter (DM), and root NSC levels. The decrease in aboveground DM correlated with reduced levels of starch, sugar and total non-structural carbohydrates. Pruning more frequently significantly decreased nodulation, the percentage N derived from the atmosphere and N2 fixed. It could be concluded that more frequent prunings decreases biomass and NSC levels which could reduce the regeneration capacity of trees since they rely on NSCs to regrow. The suppressive effects of increased pruning frequency on N2 fixation could decrease the desirable benefits of legume trees on soil N fertility improvement.
ARTICLE | doi:10.20944/preprints202209.0191.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Acinetobacter baumannii; Etlingera elatior; antibiofilm activity; essential oil
Online: 14 September 2022 (04:37:05 CEST)
The current study investigates the antibiofilm properties of essential oil extracted from the Flower of a Zingiber plant used in traditional medicines. EO from Etlingera elatior (Jack) R. M Smith tested against one of the critical nosocomial pathogens, Acinetobacter baumannii. The antibiofilm studies of Flower essential oil (FEO) by crystal violet staining method exhibited maximum inhibition of 80% at a concentration of 0.7% oil. The biochemical assays and microscopic analysis showed that the FEO significantly reduced extracellular polymeric substance production. Furthermore, FEO reduced the survival rate of A. baumannii in human blood. The chemical composition of extracted FEO was analyzed by Gas chromatography- Mass spectrometry. Dodecanal, 1-dodecanol, and alpha-pinene were identified as the major compounds. Concerning previous research, our study is the first investigation of the antibiofilm property of E. elatior flower oil. More detailed studies are required to identify the compound responsible for biofilm inhibition and its mode of action against A. baumannii biofilms.
ARTICLE | doi:10.20944/preprints202208.0511.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Zingiber cassumunar Roxb.; essential oils; microencapsulated products; antibacterial activity; agricultural pathogens; foodborne pathogens; gram-positive bacteria; gram-negative bacteria
Online: 30 August 2022 (07:02:54 CEST)
Zingiber cassumunar Roxb. is a powerful medicinal plant that has been used as traditional medicine to cure respiratory problems, pain, and inflammation in China, Indonesia, Thailand and other Asian countries by using the crude extracts. The objective of this research is to identify phytochemical composition of Z. cassumunar Roxb. and to analyze antibacterial activity of crude extract, purified compounds, and their microencapsulated products of Rhizome Z. cassumunar Roxb. Identification of phytochemical composition in crude extract of rhizome Z. cassumunar Roxb. was achieved by chromatography-mass spectrophotometer. The major phytochemical composition in crude extract of Z. cassumunar Roxb. is essential oils, including terpinen4-ol (37.7%), β-pinene (20.8%), and (E)-1-(3,4-dimethoxyphenyl)but-1-ene (13.3%). Crude extract of Z. cassumunar Roxb. was purified with silica gel flash column chromatography, resulting two purified compounds. The antibacterial activity of crude extract, purified compounds, and their microencapsulated products of Rhizome Z. cassumunar Roxb. were evaluated against agricultural and foodborne pathogens by using disc agar diffusion and broth microdilution techniques. All of the samples studied (crude extracts, purified compounds, and microencapsulated of Z. cassumunar Roxb.) were effective against all the bacteria. Based on the results of the disc-diffusion assay suggested that amongst the samples studied, purified compounds (compound 1 and 2) and microencapsulated purified compounds (compound 1 and 2) exhibited more effective against all the bacteria compared to the crude extracts. Antibacterial activity of the rhizome of Z. cassumunar Roxb. was contributed mainly by the essential oils components as the active compounds. Gram-negative bacteria (X. oryzae, X. translucens, Pseudomonas spp, E. coli, and S. typhimurium) appeared to the most resistant to the crude extracts, purified compounds, and microencapsulated of Z. cassumunar Roxb. compared to the gram-positive bacteria (S. aureus, B. cereus, and L. monocytogenes). Microencapsulated of the tested samples (crude extract, purified compound 1, and purified compound 2) of the rhizome Z. cassumunar Roxb. exhibited high antibacterial activity with no significantly different with the tested samples without microencapsulation. These results suggest potential antibacterial properties of Z. cassumunar Roxb., which useful for agricultural plant health, food preservation, natural therapies, and pharmaceuticals.
ARTICLE | doi:10.20944/preprints202208.0414.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: ethnobotanical indices; ethnobotanical uses; native and exotic species; local community; semi-structured interviews; natural resources in mountains areas; traditional knowledge and manage-ment; ornamental plants
Online: 24 August 2022 (05:51:58 CEST)
Iturbide is located in the Northeast of Mexico, it has a rich native and exotic flora, however, there are no ethnobotanical records, therefore, it requires attention in the documentation of traditional practices and uses of its botanical resources. In 2021, twelve field trips were carried out, applying 110 semi-structured interviews. Plant samples were collected, identified and deposited in an herbarium. We used the Chi-square test to compare ethnobotanical uses with respect to others reported in Mexico. To determine the cultural importance, three ethnobotanical indices were applied (UVI, ICF and FL). We recorded 250 species with ethnobotanical uses associated with 121 genera and 83 families, including 140 native and 110 exotic species. The most common plant families were Asteraceae, Lamiaceae, and Fabaceae. The main uses were ornamental, medicinal and food. The species with the highest UVI values were Lepidium peruvianum, Ocimum basilicum and Rosmarinus officinale. The multifunctionality of the native and exotic flora demonstrates the extensive knowledge associated with botanical resources. Examples, the role of ornamental plants, with a direct impact on human well-being, the resilience of healers and traditional inhabitants by using different species for the treatment of various ailments. or indigenous edible plants in the daily diet.
ARTICLE | doi:10.20944/preprints202208.0321.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: 5-aminolevulinic acid; loquat; low-temperature stress; glutathione
Online: 17 August 2022 (10:33:22 CEST)
Reduced glutathione (GSH) is an antioxidant in plants and is one of the important ways for plants to combat low-temperature stress. In this paper, Eriobotrya japonica Lindl. cv. Zaozhong No. 6 seedlings were used to study the effects of exogenous 5-aminolevulinic acid (ALA) application on glutathione synthesis and cyclic metabolism of loquat seedlings under low-temperature stress and to explore the regulatory mechanism of ALA on loquat cold tolerance. The results showed that ALA treatment could increase the content of GSH and the reduced glutathione/oxidized glutathione (GSH/GSSG) ratio in loquat leaf slices under low-temperature stress; reduce the electrolyte leakage rate and GSSG, H2O2 and MDA contents in leaf tissues; and alleviate the peroxidation damage caused by low temperature. ALA treatment increased the activity of γ-glutamine synthetase (γ-ECS) in loquat leaf slices under low-temperature stress and promoted the biosynthesis of reduced glutathione, thereby increasing the GSH content in leaf tissues. On the other hand, ALA treatment could also improve the activities of glutathione reductase (GR), glutathione S-transferase (GST) and glutathione peroxidase (GPX) and promote the cyclic regeneration of GSH, accordingly maintaining a high GSH/GSSG ratio, promoting the removal of reactive oxygen species (ROS), and enhancing the antioxidant capacity of leaves. The regulatory effect of ALA on enhancing the antioxidant capacity of loquat seedlings under low-temperature stress can be inhibited by L-buthionine-sulfoximine (BSO, GSH biosynthesis inhibitor). The results showed that ALA improved the antioxidant capacity of loquat seedlings under low-temperature stress, and GSH was involved in the regulation of the antioxidant effect of ALA on loquat seedlings under low-temperature stress.
ARTICLE | doi:10.20944/preprints202208.0315.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Transcription Factors; Evolutionary progression; Pearl millet; Phytohormones; Abiotic stress
Online: 17 August 2022 (09:50:48 CEST)
Transcription factors (TFs) are the regulatory proteins that act as molecular switches in controlling stress responsive gene expression. Among them MYB transcription factor family is one of the largest TF family in plants, playing a significant role in plant growth, development, phytohormone signaling and stress-responsive processes. Pearl millet (Pennisetum glaucum L.) is one of the most important C4 crop plant of the arid and semi-arid regions of Africa and South-east Asia for sustaining food and fodder productions. To explore the evolutionary mechanism and functional diversity of the MYB family in pearl millet, we conducted a comprehensive genome-wide survey and identified 279 MYB TFs (PgMYB) in pearl millet and distributed unevenly across seven chromosomes of pearl millet. Phylogenetic analysis of identified PgMYBs classified them into 18 subgroups and members of the same group showed a similar gene structure and conserved motif/s pattern. Further, duplication events were identified in pearl millet that indicated towards evolutionary progression and expansion of the MYB family. Transcriptome data and relative expression analysis by qRT-PCR identified differentially expressed candidate PgMYBs (PgMYB2, PgMYB9, PgMYB88 and PgMYB151) under dehydration, salinity, heat and phytohormones (ABA, SA and MeJA) treatment. Taken together, this study provides valuable information for a prospective functional characterization of MYB family members of pearl millet and genetic improvement of crop plants.
ARTICLE | doi:10.20944/preprints202208.0302.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Verticillium wilt; cotton; transmembrane protein; resistance; plant immunity
Online: 17 August 2022 (05:28:04 CEST)
Verticillium wilt (VW) is a soil borne fungal diseases caused by Verticillium dahliae Kleb, and lead to serious damage to cotton production annually in the world. In our previous study, a transmembrane protein 214 protein (TMEM214) gene associated with VW resistance was map-based cloned from Gossypium barbadense (G. barbadense). TMEM214 proteins are a kind of transmembrane protein, but their function in plants is rarely studied. To reveal the function of TMEM214s in VW resistance, all six TMEM214s were cloned from G. barbadense in this study. These genes were named as GbTMEM214-1, GbTMEM214-4 and GbTMEM214-7 according to their location on the chromosomes, and the encoded proteins are all located on cell membrane. TMEM214 genes were all induced by Verticillium dahliae inoculation and showed significant differences between resistant and susceptible varieties, but the expression patterns of GbTMEM214s under different hormone treatments were significantly different. Virus-induced gene silencing analysis showed the resistance to VW of GbTMEM214s-silenced lines decreased significantly, which further proves the important role of GbTMEM214s in the resistance to Verticillium dahliae. Our study provides an insight into the involvement of GbTMEM214s in VW resistance, which was helpful to better understand the disease resistance mechanism of plants.
ARTICLE | doi:10.20944/preprints202208.0175.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: biopesticides, ethnobotany; survey; indigenous people; Nigeria
Online: 9 August 2022 (06:11:42 CEST)
The quest for sustainable health, environmental protection and conservation of beneficial organisms makes the use of biopesticides a desirable option. This research aimed to identify botanicals used in the management of farm and household pest in Plateau State, Nigeria. A cross sectional study was carried out using semi-structured questionnaires and on the spot face-to-face interviews. The main issues captured include the pest, plants used to managed the pest, parts used, cultivation status, availability, effect on pest, formulation methods and modes of application. The quantitative data were analyzed using the Frequency of Citation (FC), Relative Frequency of Citation RFC (%) and Use Value (UV). A total of 45 plant species belonging to 42 genera, 20 orders and 30 families were found to be useful in the management of 15 different pests. The FC, RFC(%) and UV values identified the most popularly used plants as: Hyptis suaveolens, Vernonia amygdalina, Azadirachta indica, Canarium schweinfurthii and Euphorbia unispina and Erythrophloem africanum. Plants that showed broad activity include Azadirachta indica (7 uses), Erythrophloem africanum, Khaya senegalensis and Vernonia amygdalina. The perception of the respondents indicated that most of the biopesticides are available, affordable, effective, eco-friendly and safe. This survey provides a pathway for formulation of biopesticides.
ARTICLE | doi:10.20944/preprints202208.0026.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: rhizosphere; phyllosphere; endophyte; plant microbiome; plant mycobiome; rare microbiome; fungi; bacteria; microbes; soil microbiology; inoculum; microbial ecology
Online: 1 August 2022 (15:22:30 CEST)
A plant’s health and productivity is influenced by its associated microbes. Although the common microbiome is often thought to be the most influential, significant numbers of rare or uncommon microbes (eg. specialized endosymbionts) may also play an important role in the health and productivity of certain plants in certain environments. To help identify rare/specialized bacteria and fungi in the most important angiosperm plants, we contrasted microbiomes of the shoots, roots and rhizospheres of Arabidopsis, Brachypodium, maize, wheat, sugarcane, rice, tomato, coffee, common bean, cassava, soybean, switchgrass, sunflower, Brachiaria, barley, sorghum, and pea. Plants were grown inside sealed jars on sterile sand or field soil. About 95% and 86% of fungal and bacterial diversity inside plants was uncommon, however judging by read abundance, up to half of the mycobiome consists of uncommon fungal cells, while less than 11% of bacterial endophytes are rare. Uncommon seed transmitted microbiomes consisted mostly of Proteobacteria, Firmicutes, Bacteriodetes, Ascomycetes and Basidiomycetes that most heavily colonized shoots, to a lesser extent roots and least of all rhizospheres. Soil served as a more diverse source of rare microbes than seeds, replacing or excluding the majority of the uncommon seed transmitted microbiome. With the rarest microbes, their colonization pattern could either be the result of stringent biotic filtering by most plants, or uneven/stochastic inoculum distribution in seeds or soil. Several strong plant-microbe associations were observed such as seed transmission to shoots, roots and/or rhizospheres of Sarocladium zeae (maize), Penicillium (pea and Phaseolus), and Curvularia (sugarcane), while robust bacterial colonization from cassava field soil occurred with the cyanobacteria Leptolyngbya into Arabidopsis and Panicum roots, and Streptomyces into cassava roots. Some abundant microbes such as Sakaguchia in rice shoots or Vermispora in Arabidopsis roots appeared in no other samples, suggesting they were infrequent, stochastically deposited propagules from either soil or seed (impossible to know based on the available data). Future experiments with culturing and cross inoculation of these microbes between plants may help us better understand host preferences and their role in plant productivity, perhaps leading to their use in crop microbiome engineering and enhancement of agricultural production.
REVIEW | doi:10.20944/preprints202207.0404.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Abiotic stress; biotic stress; biotechnology; climate change; CRISPR; crop improvement; genome editing
Online: 26 July 2022 (10:44:22 CEST)
Climate change poses a serious threat to global agricultural activity and food production. To address this issue, plant genome editing technologies have been developed to provide an alternative solution for crop improvement. Unlike conventional breeding techniques (e.g., selective breeding and mutation breeding), modern genome editing tools offer more targeted and specific alterations of the plant genome to produce crops with desired traits, such as higher yield and/or stronger resilience to the changing environment. In this review, we discuss the current development and future applications of genome editing technologies in mitigating the impacts of biotic and abiotic stresses on agriculture. We focus specifically on the CRISPR/Cas system, which has been the center of attention in the last few years as a revolutionary genome-editing tool in various species. We also conducted a bibliographic analysis on CRISPR-related papers published from 2012 to 2021 (10 years) to identify trends and possible gaps in the CRISPR/Cas-related plant research. In addition, this review article outlines the current shortcomings and challenges of employing genome editing technologies in agriculture with notes on future prospective. We believe combining conventional and more innovative technologies in agriculture would be the key to optimizing crop improvement beyond the limitations of traditional agricultural practices.
REVIEW | doi:10.20944/preprints202207.0387.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Artocarpus; Artocarpus camansi; kamansi; phytochemistry; pharmacology; secondary metabolites
Online: 26 July 2022 (05:52:46 CEST)
Artocarpus camansi Blanco or breadnut (Family: Moraceae) is primarily found in tropical regions of the world. Different parts of the plant provide potential use in medicine, nutraceutical development, and livelihood. The present review attempts to document literature on the traditional use, nutritional value, phytochemistry, and pharmacological investigation carried out with breadnuts. The included literatures of the plant were collected from various sources and databases like Google scholar, PubMed, ScienceDirect, Crossref, and Scopus. Breadnuts are rich in secondary metabolites. Studies have reported the isolation of several triterpenoid compounds and the broad spectrum of its pharmacological activities such as antidiabetic, antimalarial, antioxidant, anti-tumor, antibacterial, and immunomodulatory properties. The approximate composition of the seed and the fruit also highlights the nutritional importance of this plant. A. camansi Blanco is an underutilized tree that holds significant potential if further research and sustainable conservation is applied. Efforts to mainstream its use as functional food and increase awareness among the locals should also be given attention.
ARTICLE | doi:10.20944/preprints202207.0334.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Rubber tree capillovirus 1; microRNAs; plant-virus interaction; RNAi: computational algorithms; gene silencing, minimum free energy
Online: 22 July 2022 (09:52:38 CEST)
Tapping panel dryness (TPD) syndrome is a complex disease of Rubber tree (Hevea brasiliensis L.) which causes cessation of latex drainage upon tapping of rubber tree. Rubber tree virus (RTV1) was identified as a novel pathogen associated with rubber tree and a potential causal agent of TPD. RTV1 is a monopartite RNA virus that is linear, non-enveloped and has a single-stranded (ss) positive RNA genome of approximately 6081 nucleotides and is composed of two major open reading frames (ORFs), ORF1 (polyprotein), and ORF2 (movement protein. This study aimed to investigate the possibility of rubber genome encoded tree microRNAs (miRNAs) as novel therapeutic targets against RTV1 using in silico algorithms. Mature rubber tree miRNAs are retrieved from the miRBase database and are used for hybridization of RTV1 using five different five different computational algorithms including miRanda, RNA22, RNAhybrid and psRNATarget. A total of eleven common rubber tree miRNAs were identified based on consensus genomic positions. The consensus of four algorithms predicted the hybridization sites of hbr-miR396a and hbr-miR398 at common locus positions 6676, 1840 respectively. To validate the prediction, secondary structures of the consensual rubber tree miRNAs and free energy of duplex binding were calculated using the RNAfold and RNAcofold algorithms respectively. We created a plot between rubber tree miRNAs and RTV1 ORFs by using Circos algorithm. In this study, we predicted eleven consensual rubber tree miRNAs. Among these miRNAs, hbr-miR398 was identified as the most effectual miRNA that may target the ORF1 gene of the RTV1 genome. The predicted data will be important in the development of rubber trees resistant to RTV1.
REVIEW | doi:10.20944/preprints202207.0309.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: ubiquitin; E3 ligase; chloroplast; stress; photosynthesis; homeostasis; enzymes
Online: 21 July 2022 (03:20:20 CEST)
Chloroplasts are ancient organelles responsible for photosynthesis and various biosynthetic functions essential to most life on Earth. Many of these functions require tightly controlled regulatory processes to maintain homeostasis at the protein level. One such regulatory mechanism is the ubiquitin-proteasome system whose fundamental role is increasingly emerging in chloroplasts. In particular, the role of E3 ubiquitin ligases as determinants in the ubiquitination and degradation of specific intra-chloroplast proteins. Here, we highlight recent advances in understanding the roles of plant E3 ubiquitin ligases in chloroplast function.
ARTICLE | doi:10.20944/preprints202207.0293.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: altitudinal variation; nutrient composition; Quercus leucotrichophora; seasonal variation
Online: 20 July 2022 (05:12:55 CEST)
Quercus leucotrichophora leaves were collected for assessment of nutritive composition between four seasons i.e. spring season (March-April), summer season (June-July), autumn (September-October), winter December-January) respectively, in 2017. The experiment was conducted within the laboratory of Shoolini University campus. Leaves samples were collected from 12 different provenances starting from 1189 to 2578 m a.s.l. Crude protein, ash content, ether extract, phenol content, total sugar and tannin content were expressively higher within middle to higher altitudinal populations. Crude fiber, ether extract, acid detergent fibre, neutral detergent fibre, saponin content were higher in winter month while crude protein, ash content, phenol content, tannin content were higher in autumn season. Total sugar was higher in summer season and nitrogen free extract was higher in spring season. Q. leucotrichophora leaves were harvested at the right stage of maturity (winter months) offers considerable potential as good quality forage for livestock to meet the deficiency of nutritive components.
ARTICLE | doi:10.20944/preprints202207.0143.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: pollination; pollen adhesion; pollenkitt; atomic force microscopy; cryogenic scanning electron microscopy; centrifugation
Online: 10 July 2022 (05:57:28 CEST)
Although pollination is one of the most crucial biological processes that ensures plant reproduction, its mechanisms are poorly understood. Especially in insect-mediated pollination, a pollen undergoes several attachment and detachment cycles when being transfered from anther to insect and from insect to stigma. The influence of the surface properties of pollen, insect and floral surfaces on the adhesion forces that mediate pollen transfer are poorly studied. Here, we investigate the adhesive properties of Hypochaeris radicata pollen and their dependence on pollen ageing by quantifying the pull-off forces from glass slides using centrifugation and atomic force microscopy. We found that the properties of the pollenkitt – the viscous, lipid liquid on the surface of most pollen grains – influences the forces necessary to detach a pollen from hydrophilic surfaces. Our results show that aged H. radicata pollen form weaker adhesions to hydrophilic glass than fresh ones. On the other hand, when a pollen grain ages in contact with glass, the adhesion between the two surfaces increases over time. This study shows for the first time the pollen ageing effect on the pollination mechanism.