ARTICLE | doi:10.20944/preprints202010.0357.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: unpadded; strip tillage; crop residues; yield
Online: 16 October 2020 (19:35:42 CEST)
On-farm research was conducted at Gouripur sub-district under Mymensingh district of Bangladesh during boro (mid November-June) season in 2013-14 and 2014-15 to evaluate the performance of unpadded rice cultivation with crop residue retention. The rice var. BRRI dhan28 was transplanted by two tillage practices viz., puddled conventional tillage (CT) and non-puddled strip tillage (ST) and two levels of mustard residues, i.e., no residue (R0) and 50% residue (R50). The experiment had designed in a randomized complete block design with four replications. There were no significant yield differences between tillage practices and residue levels in 2013-14. But in the following year, ST yielded higher grains (5.72 t ha-1), which was about 9.36 % higher compared to CT. The higher grain yield in ST, leading to 22.23% higher BCR compared to CT. Retention of 50% residue increased by 3.15 % yield compared to no-residue, which contributed to 10.58 % higher benefit-cost ratio (BCR). The ST combine with 50 % residue retention yielded the highest grain yield (5.81 t ha-1) which credited to obtain the highest BCR (1.06).
Thu, 1 October 2020
ARTICLE | doi:10.20944/preprints202010.0001.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Association mapping; chromosomes; drought tolerance; markers, structure; traits
Online: 1 October 2020 (08:40:47 CEST)
The objective of this study were to conduct association mapping for drought tolerance at the seedling stage and yield-related traits. 60 cowpea accessions were used in the study. Single-nucleotide polymorphisms (SNPs) discovered through genotyping by sequencing (GBS) were used for genotyping. Association mapping was conducted using single-marker regression (SMR) in Q Gene, and general linear model (GLM) and mixed linear model (MLM) built in TASSEL. The population of the cowpea accessions were analysed using STRUCTURE 2.3.4 and the peak of delta K in the greenhouse showed seven population types, whereas the peak of delta K in the glasshouse indicated the presence of six population types. One SNP marker, 14083649|F|0-9 was associated with NP with a p value <0.001. Fifty SNP markers were associated with PWT at p <0.001. Four SNP markers, 14074781|F|0-16, 100047392|F|0-36, 14083801|F|0-28 and 100051488|F|0-49 were associated with AVSPD at p <0.001. SNP markers, 14074781|F|0-16, 14083801|F|0-28 and 100051488|F|0-49 were associated with PL at P <0.001. Five SNP markers, 100047392|F|0-36, 14083801|F|0-28, 100072738|F|0-34, 14076881|F|0-49 and 14076881|F|0-49 were associated with PWDTH at p <0.001. The 65 SNP markers identified can be used in cowpea molecular breeding to select for AVSPD, NP, PL, PWDTH, PWT, and RR through marker assisted selection (MAS).
Tue, 29 September 2020
ARTICLE | doi:10.20944/preprints202009.0646.v2
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Grapevine leafroll disease; viromics; dsRNA extraction; virus epidemiology; virus co-occurrence; Vitis vinifera; interspecific hybrid
Online: 29 September 2020 (08:49:24 CEST)
Quebec is the third-largest wine grape producing province in Canada, and the industry is constantly expanding. Traditionally, 90% of the grapevine cultivars grown in Quebec were rustic or semi-rustic and largely dominated by winter hardy interspecific hybrid Vitis sp. cultivars. Over the years, the winter protection techniques adopted by growers and climate changes have offered an opportunity to establish V. vinifera L. cultivars (e.g. Pinot Noir). We characterized the virome of leafroll-infected interspecific hybrid cultivar and compared it to the virome of V. vinifera cultivar to support and facilitate the transition of the industry. A dsRNA sequencing method was used to sequence symptomatic and asymptomatic grapevine leaves of different cultivars. The results suggested a complex virome in terms of composition, abundance, richness, and phylogenetic diversity. Three viruses, grapevine Rupestris stem pitting-associated virus, grapevine leafroll-associated virus (GLR) 3 and 2 and hop stunt viroid (HSVd) largely dominated the virome. However, their presence and abundance varied among grapevine cultivars. The symptomless grapevine cultivar Vidal was frequently infected by multiple virus and viroid species and different strains of the same virus, including GLR virus 3 and 2. Our data shows that viruses and viroids associated with the highest number of grapevines expressing symptoms included HSVd, GLR3 and GLR2, in gradient order. However, co-occurrence analysis revealed that the presence of GLR species was randomly associated with the development of virus-like symptoms. These findings and their implication for grapevine leafroll disease management were discussed.
Sat, 19 September 2020
ARTICLE | doi:10.20944/preprints202009.0458.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: machine learning; deep leaning; physiological maturity; computer vision; plant breeding; Phenology; Glycine max (L.) Merr.
Online: 19 September 2020 (10:08:43 CEST)
Soybean maturity is a trait of critical importance for the development of new soybean cultivars, nevertheless, its characterization based on visual ratings has many challenges. Unmanned aerial vehicles (UAVs) imagery-based high-throughput phenotyping methodologies have been proposed as an alternative to the traditional visual ratings of pod senescence. However, the lack of scalable and accurate methods to extract the desired information from the images remains a significant bottleneck in breeding programs. The objective of this study was to develop an image-based high-throughput phenotyping system for evaluating soybean maturity in breeding programs. Images were acquired twice a week, starting when the earlier lines began maturation until the latest ones were mature. Two complementary convolutional neural networks (CNN) were developed to predict the maturity date. The first using a single date and the second using the five best image dates identified by the first model. The proposed CNN architecture was validated using more than 15,000 ground truth observations from five trials, including data from three growing seasons and two countries. The trained model showed good generalization capability with a root mean squared error lower than two days in four out of five trials. Four methods of estimating prediction uncertainty showed potential at identifying different sources of errors in the maturity date predictions. The architecture used solves limitations of previous research and can be used at scale in commercial breeding programs.
REVIEW | doi:10.20944/preprints202009.0449.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: oleaginous microorganisms; microbial lipids; lignocellulose pretreatment; enzymatic hydrolysis; inhibitors
Online: 19 September 2020 (05:16:42 CEST)
The microorganisms able of accumulating lipids in high percentages, known as oleaginous microorganisms, have been widely studied as an alternative for producing oleochemicals and biofuels. Microbial lipid, so called Single Cell Oil (SCO), production depends on several growth parameters, including the nature of the carbon substrate, which must be efficiently taken up and converted into storage lipid. Οn the other hand, substrates considered for large scale applications must be abundant and of low acquisition cost. Among others, lignocellulosic biomass is a promising renewable substrate containing high percentages of assimilable sugars (hexoses and pentoses). However, it is also highly recalcitrant and therefore it requires specific pretreatments in order to release its assimilable components. The main drawback of lignocellulose pretreatment is the generation of several by-products that can inhibit the microbial metabolism. In this review, we discuss the main aspects related to the cultivation of oleaginous microorganisms using lignocellulosic biomass as substrate, hoping to contribute to the development of a sustainable process for SCO production in the near future.
ARTICLE | doi:10.20944/preprints202009.0444.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: blueberry; crop modeling; plant nutrition; machine learning
Online: 19 September 2020 (03:27:32 CEST)
Nutrient management of lowbush blueberry (Vaccinium angustifolium Ait.) depends on several yield-limiting features. Machine learning models can process such yield-impacting variables to predict berry yield. We investigated the effects of local variables on yields and nutrient management of lowbush blueberry. We collected 1504 observations from N-P-K fertilizer trials conducted in Quebec, Canada. Meteorological indices at various phenological stages showed the greatest impact on yield. High mean temperature at flower bud opening and after fruit maturation, and total precipitation at flowering showed positive effects. Low mean temperature and low total precipitation before bud opening, at flowering, and by fruit maturity, as well as number of freezing days (< -5ºC) before flower bud opening, showed negative effects. Soil fertility variables, leaf nutrient compositions and N-P-K fertilization showed smaller effects. Gaussian processes predicted berry yields from historical weather data, soil analysis, fertilizer dosage, and leaf nutrients with a root-mean-square-error of 1447 kg ha-1 on the testing data set. An in-house Markov chain algorithm optimized yields modelled with Gaussian processes from leaf nutrient composition, soil test value, and fertilizer dosage conditioned to specified historical weather features. We propose to use conditioned machine learning models to manage nutrients of lowbush blueberry at local scale.
Thu, 17 September 2020
ARTICLE | doi:10.20944/preprints202009.0386.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: RTE salads; Microbiological quality; shelf-life; MBS method
Online: 17 September 2020 (08:03:50 CEST)
The market of ready-to-eat salads is experiencing a noticeable growth in Europe. Since they are intended to be consumed without additional treatments, these ready-to-eat products are associated with a high microbiological risk. The aim of this work was to evaluate the microbiological quality and safety of ready-to-eat salads sold in widespread supermarket chains in Lazio, Italy, at the packaging date, during shelf-life and during home-refrigeration. The study also aimed to determine the differences between low, medium, and high cost products. Salmonella spp., L. monocytogenes were chosen as safety indicators as specified by European regulations while total aerobic mesophilic bacteria and Escherichia coli were chosen as quality indicators as suggested by national guidelines. Analyses were performed following the ISO standards and in parallel, for the evaluation of total aerobic mesophilic bacteria, with an alternative colorimetric system, the Micro Biological Survey method, in order to propose a simple, affordable and accurate alternative for testing the microbiological quality of products, especially suitable for small and medium enterprises and on-site analyses. The study revealed high, unsatisfactory, total bacterial loads in all analyzed samples at the packaging date and expiring date and a very high prevalence of Salmonella spp. (67%) regardless of the selected varieties and cost-categories; L. monocytogenes was instead not recovered aligning with the results obtained in other studies.
ARTICLE | doi:10.20944/preprints202007.0336.v3
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Prediction accuracy; Mixed linear and Bayesian models; Machine Learning algorithms; Training set size and composition; Parametric and nonparametric models
Online: 17 September 2020 (05:41:51 CEST)
Genomic selection (GS) can accelerate variety improvement when training set (TS) size, and its relationship with the breeding set (BS) are optimized for prediction accuracies (PA) of genomic prediction (GP) models. Sixteen GP algorithms were run on phenotypic best linear unbiased predictors (BLUPs) and estimators (BLUEs) of resistance to both fall armyworm (FAW) and maize weevil (MW) in a tropical maize panel. For MW resistance, 37% of the panel was the TS, and BS was the remainder whilst for FAW, random-based training sets (RBTS) and pedigree-based training sets (PBTS) were designed. PAs achieved with BLUPs varied from 0.66 to 0.82 for MW resistance traits, and, for FAW resistance, 0.694 to 0.714 for RBTS of 37%, and 0.843 to 0.844 for RBTS of 85%, and, these were at least two-fold those from BLUEs. For PBTS, FAW resistance PAs were generally higher than those for RBTS, except for one dataset. GP models generally showed similar PAs across individual traits whilst the TS designation was determinant since a positive correlation (R=0.92***) between TS size and PAs was observed for RBTS and, for the PBTS, it was negative (R=0.44**). This study pioneers the use of GS for maize resistance to insect pests in sub-Saharan Africa.
Wed, 16 September 2020
ARTICLE | doi:10.20944/preprints202009.0345.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: food safety; SARS-CoV-2; coronavirus; ACEII; agricultural security; national security
Online: 16 September 2020 (03:57:36 CEST)
Coronavirus is now a significant human pathogen with the emergence of SARS-CoV-2. Until now there has been no data to support a threat to agricultural industries. Using a comparative genomic protein analysis, this study examined the angiotensin-converting enzyme II (ACEII) gene of 17 animal species with an emphasis on agriculture. To determine viral vulnerability the 20 known SARS-CoV-2 receptor-binding domain (RBD)/ACEII receptor interaction sites were compared to determine their potential susceptibility to the SARS-CoV-2 virus. With the known bat host’s (XP_032963186) number of binding sites as a threshold, we note that ALL animal species examined in this study contained significant numbers (≥10) of SARS-CoV-2 binding sites and could be at risk for SARS-CoV-2 infection. The data from this study suggest SARS-CoV-2 imposes a grave threat to the safety and security of the agricultural industry. Urgent studies are needed to determine if infected animals can transmit SARS-CoV-2 before and/or after processing.
Mon, 14 September 2020
ARTICLE | doi:10.20944/preprints202009.0142.v3
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Plant Diseases; Modern Agriculture; Plant Health; AWS DeepLens; SageMaker; Machine Learning; Deep Learning
Online: 14 September 2020 (06:24:16 CEST)
In the Agriculture sector, control of plant leaf diseases is crucial as it influences the quality and production of plant species with an impact on the economy of any country. Therefore, automated identification and classification of plant leaf disease at an early stage is essential to reduce economic loss and to conserve the specific species. Previously, to detect and classify plant leaf disease, various Machine Learning models have been proposed; however, they lack usability due to hardware incompatibility, limited scalability and inefficiency in practical usage. Our proposed DeepLens Classification and Detection Model (DCDM) approach deal with such limitations by introducing automated detection and classification of the leaf diseases in fruits (apple, grapes, peach and strawberry) and vegetables (potato and tomato) via scalable transfer learning on A.W.S. SageMaker and importing it on AWS DeepLens for real-time practical usability. Cloud integration provides scalability and ubiquitous access to our approach. Our experiments on extensive image data set of healthy and unhealthy leaves of fruits and vegetables showed an accuracy of 98.78% with a real-time diagnosis of plant leaves diseases. We used forty thousand images for the training of deep learning model and then evaluated it on ten thousand images. The process of testing an image for disease diagnosis and classification using AWS DeepLens on average took 0.349s, providing disease information to the user in less than a second.
REVIEW | doi:10.20944/preprints202009.0308.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Tomato; genetic breeding value; training population; genotyping; marker effect; phenotyping; selection schemes
Online: 14 September 2020 (00:08:23 CEST)
Genomic selection (GS) is a predictive approach that was build up to increase the rate of genetic gain per unit of time in breeding programs. It has emerged as a valuable method for improving complex traits that are controlled by many genes with small effect. GS enables the prediction of breeding value of candidate genotypes for selection. In this work we address important issues related to GS and its implementation in tomato breeding context. Genomic constrains and critical parameters affecting the accuracy of prediction in such crop such as phenotyping, genotyping training population composition and size and statistical method should be carefully evaluated. Comparison of GS approaches for facilitating the selection of tomato superior genotypes during breeding program are also discussed. GS applied to tomato breeding has already shown to be feasible. We illustrated how GS can improve the rate of gain in elite lines selection, descendent and in backcross schemes. The GS schemes begin to be delineated and computer science can provide support for future selection strategies. A new breeding framework is beginning to emerge for optimizing tomato improvement procedures.
Tue, 8 September 2020
ARTICLE | doi:10.20944/preprints202009.0176.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: soil health; soil organic matter; greenhouse gases; climatic change scenarios; Chernozems; long-term experiment
Online: 8 September 2020 (06:11:53 CEST)
Organic carbon (OC) accumulation in soil mitigates greenhouse gases emission and improves soil health. We aimed to quantify the dynamics of OC stock in soils and to justify technologies that allow annual increasing OC stock in the arable soil layer by 4‰. We based the study on a field experiment established in 1936 in the 9-field crop rotation with a fallow on Chernozem in European Russia. The RothC version 26.3 was used for the reproducing and forecasting OC dynamics. In all fertilizer applications at FYM background, there was a decrease in the OC stock with preferable loss of active OC, except the period 1964-71 with 2-5‰ annual OC increase. The model estimated the annual C input in the arable soil layer as 1,900 kg·ha-1. For increasing OC stocks by 4‰ per year, one should raise input to 2400 kg·ha-1. Simulation was made for 2016-2090 using climate scenarios RCP4.5 and RCP8.5. Crop rotation without fallowing provided an initial increase of 3‰ and 6‰ of stocks in the RCP8.5 and RCP4.5 scenarios accordingly, followed by a loss in accumulated OC. Simulation demonstrates difficulties to increase OC concentration in Chernozems under intensive farming and potential capacity to rise OC stock through yield management.
Mon, 7 September 2020
ARTICLE | doi:10.20944/preprints202009.0142.v2
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Plant Diseases; Modern Agriculture; Plant Health; AWS DeepLens; SageMaker; Machine Learning; Deep Learning
Online: 7 September 2020 (10:08:00 CEST)
In the Agriculture sector, control of plant leaf diseases is crucial as it influences the quality and production of plant species with an impact on the economy of any country. Therefore, automated identification and classification of plant leaf disease at an early stage is essential to reduce economic loss and to conserve the specific species. Previously, to detect and classify plant leaf disease, various Machine Learning models have been proposed; however, they lack usability due to hardware incompatibility, limited scalability and inefficiency in practical usage. Our proposed DeepLens Classification and Detection Model (DCDM) approach deal with such limitations by introducing automated detection and classification of the leaf diseases in fruits (apple, grapes, peach and strawberry) and vegetables (potato and tomato) via scalable transfer learning on A.W.S. SageMaker and importing it on A.W.S. DeepLens for real-time practical usability. Cloud integration provides scalability and ubiquitous access to our approach. Our experiments on extensive image data set of healthy and unhealthy leaves of fruits and vegetables showed an accuracy of 98.78% with a real-time diagnosis of plant leaves diseases. We used forty thousand images for the training of deep learning model and then evaluated it on ten thousand images. The process of testing an image for disease diagnosis and classification using A.W.S. DeepLens on average took 0.349s, providing disease information to the user in less than a second.
Sun, 6 September 2020
ARTICLE | doi:10.20944/preprints202009.0142.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Diseases; A.W.S. DeepLens; SageMaker; Machine Learning; Deep Learning
Online: 6 September 2020 (15:33:05 CEST)
In the Agriculture sector, control of plant leaf diseases is crucial as it influences the quality and production of plant species with an impact on the economy of any country. Therefore, automated identification and classification of plant leaf disease at an early stage is essential to reduce economic loss and to conserve the specific species. Previously, to detect and classify plant leaf disease, various Machine Learning models have been proposed; however, they lack usability due to hardware incompatibility, limited scalability and inefficiency in practical usage. Our proposed DeepLens Classification and Detection Model (D.C.D.M.) approach deal with such limitations by introducing automated detection and classification of the leaf diseases in fruits (apple, grapes, peach and strawberry) and vegetables (potato and tomato) via scalable transfer learning on A.W.S. SageMaker and importing it on A.W.S. DeepLens for real-time practical usability. Cloud integration provides scalability and ubiquitous access to our approach. Our experiments on extensive image data set of healthy and unhealthy leaves of fruits and vegetables showed an accuracy of 98.78% with a real-time diagnosis of plant leaves diseases. We used forty thousand images for the training of deep learning model and then evaluated it on ten thousand images. The process of testing an image for disease diagnosis and classification using A.W.S. DeepLens on average took 0.349s, providing disease information to the user in less than a second.
Sat, 5 September 2020
REVIEW | doi:10.20944/preprints202009.0123.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Brazilian artisanal cheeses; safety; challenges
Online: 5 September 2020 (06:08:11 CEST)
Artisanal cheeses made with raw milk are highly appreciated products in Brazil. Most of these cheeses are produced in small properties across different production regions in the country, many of which have been granted a protected designation of origin. The most prominent state that manufactures these products is Minas Gerais, but production is also gaining strength in other Brazilian states. This text presents an overview of the many types of artisanal cheeses produced in the country, grouped by geographical regions, and reviews the current challenges faced by producers and government considering the safety of these cheeses.
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Euphorbia helioscopia; fungal pathogens; spore suspension; sustainable agriculture
Online: 5 September 2020 (04:02:35 CEST)
Euphorbia helioscopia is a common weed of the agricultural crops, it not only competes with the crop plants for food and space but also causes a significant losses to the final crop production. Therefore, it was need of the hour to find some sustainable approach to control this weed in agricultural lands. An experiment was conducted to access the potential of various fungal organisms (Alternaria tenuissimia, Alternaria alternata and Fusarium oxysporum) to inhibit the growth of Euphorbia helioscopiai in vegetable crops. E. helioscopia was transplanted in March 2020, the experiment was designed with three treatments and having five replicates for each treatment. Plantlets were inoculated with different concentrations (1×103, 1×105, 1×107 spores/ml.) of fungal spore suspensions of selected fungi. A control experiment was also added in the experiment which was not inoculated with any of the spore suspension. Maximum disease severity was observed in case of inoculation with the spore suspension of Alternaria tenuissimia. The agronomic traits which were observed after inoculation as indicator were number of infected leaves, number of infected plants, and number of spots on leaves. Control experiment has exhibited the plants without any sign of infection.
Fri, 4 September 2020
ARTICLE | doi:10.20944/preprints202007.0336.v2
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Prediction accuracy; Mixed linear and Bayesian models; Machine Learning algorithms; Training set size and composition; Parametric and nonparametric models
Online: 4 September 2020 (12:58:42 CEST)
Genomic selection (GS) can accelerate variety release by shortening the variety development phase when factors that influence prediction accuracies (PA) of genomic prediction (GP) models such as training set (TS) size and relationship with the breeding set (BS) are optimized beforehand. In this study, PAs for the resistance to fall armyworm (FAW) and maize weevil (MW) in a diverse tropical maize panel composed of 341 double haploid and inbred lines were estimated using 16 parametric, semi-parametric, and nonparametric algorithms with a 10-fold and 5 repetitions cross-validation strategy. For MW resistance, 126 lines that had both genotypic and phenotypic data were used as a TS (37% of the panel) and the remaining lines, with only genotypic data, as a BS. Regarding FAW damage resistance, two TS determination strategies, namely: random-based TS (RBTS) with increasing sizes (37, 63, 75, and 85%) and pedigree-based TS (PBTS) were used. For both MW and FAW resistance datasets with an RBTS of 37%, PAs achieved with phenotypic best linear unbiased predictors were at least as twice as higher than those realized with best linear unbiased estimators. The PAs achieved with BLUPs for MW resistance traits varied from 0.66 to 0.82. The PAs with BLUPs for FAW resistance datasets ranged from 0.694 to 0.714 for RBTS of 37%, and 0.843 to 0.844 for RBTS of 85%. The PAs with BLUPs for FAW resistance with PBTS were generally high varying from 0.83 to 0.86, except for the third dataset which had the largest TS (86.22% of the panel) with PAs ranging from 0.11 to 0.75. GP models showed generally similar predictive abilities for each trait while the TS designation was determinant. There was a highly positive correlation (R=0.92***) between TS size and PAs for the RBTS approach while, for the PBTS, these parameters were highly negatively correlated (R=-0.44***), indicating the importance of the relationship between the TS and the BS with the smallest TS (31%) achieving the highest PAs (0.86). This study paves the way towards the use of GS for maize resistance to insect pests in sub-Saharan Africa.
Mon, 31 August 2020
ARTICLE | doi:10.20944/preprints202008.0725.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: litchi; fruit bagging; bag colours; dates; quality
Online: 31 August 2020 (16:25:13 CEST)
Litchi orchards of 15 year age in Pantnagar were subjected to different fruit bagging treatments in study entitled “Impact of pre-harvest fruit bagging technology on growth and quality traits in litchi cv. Rose Scented under Indian prospective”. The combination includes white and pink polypropylene bags practiced on three dates i.e. 15, 25 and 30 days after fruit set and a control. Hence, study comprised of 7 treatment combination in total. The data of year 2017 and 2018 as well as pooled data revealed that T1 i.e. white polypropylene bags + bagging 15 days after fruit set was found to be promising in attributes such as fruit cracking (%) and Sun burn (%). T3 White Polypropylene bags + bagging 30 days after fruit set was found best for fruit Weight (g) and Acidity (%), T4 Pink Polypropylene bags + bagging 15 days after fruit set was found promising for TSS (0Brix), T6-Polypropylene Pink + 10th May (30 days after fruit set) was observed to be best for most of the desired attributes viz. Fruit breadth (mm), Yield (Kg/tree), Acidity (%), Anthocyanin (mg/100g), Fruit colour (visual), borer infestation (%) and B:C Ratio. However, fruits without bagging i.e. control were found to have inferior appearance and have maximum fruit cracking (%) and sun burn (%). Thus the bagging of litchi fruits with white polypropylene bags 15 days after fruit set resulted in lesser cracking and sunburn incidence. For other attributes, polypropylene pink bagged 30 days after fruit set was found promising. In Litchi under Indian condition, the novel technique of fruit bagging significantly enhance the fruit appearance and quality.
Online: 31 August 2020 (08:12:19 CEST)
For a considerable length of time synthetic composts are utilized to satisfy the dirt necessity of supplements and yield, however huge measure of these substance manures are hazardous for condition, advantageous microorganisms, creatures, and people also. In this way, natural inviting and savvy biofertilizers are utilized. Biofertilizer are the substances which contain microorganisms those microorganisms might be growths, microscopic organisms, and protozoa which have capacity to build ripeness of soil by Nitrogen obsession, Phosphorous solubilization, and Iron sequestration. These cycles convert insoluble type of supplements into solvent structure and make it accessible to the foundations of plant which effectively take them up and use them. There are assortment of the yields whose profitability can be expanded by applying biofertilizer, for example, rice, oat, and other grain crops. In this audit we experience the method of utilization of biofertilizers, and how the assistance the plants and in which they help.
Fri, 28 August 2020
ARTICLE | doi:10.20944/preprints202008.0631.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Acidity attributes; fruit minerals; grapevine physiology; phenolic compounds; volatile compounds
Online: 28 August 2020 (10:20:31 CEST)
Kaolin protective effect was assessed in a white grapevine cultivar ‘Cerceal’ in ‘Alentejo’ Region (southeast Portugal) where plants face extreme conditions during summer season. We addressed the hypothesis that kaolin effects lead to several changes in leaves, fruits and wine characteristics on the primary and secondary metabolism. Results showed that kaolin reduces leaf temperature which provoke an improvement in physiological parameters such as net photosynthesis and water use efficiency. This protection interferes with berries colour, leaving them more yellowish, and an increase in phenolic compounds were observed in all fruit tissues (skin, seed and pulp). Also, both berry and wine characteristics were strongly affected, with an increase of tartaric and malic acid and consequently high total acidity, while the sugar concentration decreased 8.9% in berries provoking a low wine alcohol level. Results also showed that kaolin induces high potassium, magnesium and iron, and low copper and aluminum concentrations. Moreover, the control wine showed higher content of esters related with hostile notes whereas wine from kaolin treated vines presented higher content of esters associated with fruity notes. Overall, the results strengthen the promising nature of kaolin application as summer stress mitigation strategy protecting grapevine plants and improving fruits quality and more balanced wines.
Wed, 26 August 2020
ARTICLE | doi:10.20944/preprints202008.0570.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: apothecium; ascospores; sclerotium formation; carbon source; fungicides; resistance source
Online: 26 August 2020 (09:01:24 CEST)
A new disease causing the tan to light brown blighted stems and pods has occurred in 2.6% pea (Pisum sativum L.) plants with an average disease severity rating of 3.7 in Chapainawabganj district, Bangladesh. A fungus with white appressed mycelia and large sclerotia was consistently isolated from symptomatic tissues. The fungus formed funnel-shaped apothecia with sac-like ascus and endogenously formed ascospores. Healthy pea plants inoculated with the fungus produced typical white mold symptoms. The internal transcribed spacer sequences of the fungus were 100% similar to that recovered from an epitype of Sclerotinia sclerotiorum, considering the fungus to be the causative agent of white mold. Mycelial growth and sclerotial development of S. sclerotiorum were favored at 20°C and pH 5.0. Glucose was the best carbon sources to support hyphal growth and sclerotia formation. Bavistin and Amistar Top inhibited the radial growth of the fungus completely at the lowest concentration. In planta, foliar application of Amistar Top showed the considerable potential to control the disease at 1.0% concentration until 7 days after spraying, while Bavistin prevented infection significantly until 15 days after spraying. A large majority (70.93%) of genotypes including tested released pea cultivars were susceptible, while six genotypes (6.98%) appeared resistant to the disease. These results could be important for management strategies aiming to control the incidence of S. Sclerotinia and eliminate yield loss in pea.
Fri, 21 August 2020
ARTICLE | doi:10.20944/preprints202008.0471.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Zea mays; maize; corn; rhizosphere; 16S rRNA gene; ITS; fungicide; plant growth promoting rhizobacteria
Online: 21 August 2020 (05:10:34 CEST)
The targeted application of plant growth promoting rhizobacteria (PGPR) provides the key for a future sustainable agriculture with reduced pesticide application. PGPR interaction with the indigenous microbiota is poorly understood but essential to develop reliable applications. Therefore, Stenotrophomonas rhizophila SPA-P69 was applied as seed coating and in combination with a fungicide based on the active ingredients fludioxonil, metalaxyl-M, captan and ziram. Plant performance and rhizosphere composition of treated and non-treated maize plants of two field trials were analyzed. Plant health was significantly increased by treatment; however overall corn yield was not changed. By applying high-throughput amplicon sequencing of the 16S rRNA and the ITS genes, the bacterial and fungal changes in the rhizosphere due to different treatments were determined. Despite treatments had a significant impact on the rhizosphere microbiota (9- 12%), the field site was identified as main driver (27- 37%). Soil microbiota composition from each site was significantly different, which explains the site-specific effects. In this study we were able to show first indications how PGPR treatments increase plant health via microbiome shifts in a site-specific manner. This way first steps towards a detailed understanding of PGPRs and developments of consistently efficient applications in diverse environments are set.
Thu, 20 August 2020
ARTICLE | doi:10.20944/preprints202008.0423.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: gene editing; mutagenesis; genetically modified; GMO; crop breeding; RNP; genetic screening
Online: 20 August 2020 (04:34:55 CEST)
CRISPR-Cas9 technology allows the modification of DNA sequences in vivo at the location of interest. Although CRISPR-Cas9 can produce genomic changes that do not require DNA vector carriers, the use of transgenesis for stable integration of DNA coding for gene-editing tools into plant genomes is still the most used approach and it can generate unintended transgenic integrations, while Cas9 prolonged expression can increase cleavage at off-target sites. In addition, the selection of genetically modified cells from millions of treated cells, especially plant cells, is still challenging. These downfalls can be avoided with the delivery of preassembled ribonucleoprotein complexes (RNPs) composed of purified recombinant enzyme Cas9 and in vitro- transcribed guide RNA (gRNA) molecules in a protoplast system. We therefore aimed to develop the first DNA-free protocol for gene-editing in maize and introduced RNPs into their protoplasts with PEG 4000. We performed effective transformation of maize protoplasts using different gRNAs sequences targeting the inositol phosphate kinase gene and applying two different exposure times to RNPs. Using low-cost Sanger sequencing protocol, we observed an efficiency rate of 0.85 up to 5.85%, which is equivalent to DNA-free protocols used in other plant species. A positive correlation was displayed between exposure time and mutation frequency. Mutation frequency was gRNA sequence- and exposure time-dependent. In summary, we demonstrated the suitability of RNP transfection as an effective screening platform for gene-editing in maize. This efficient and relatively easy assay method for selection of gRNA suitable for editing of gene of interest will be highly useful for genome editing in maize, since genome size and GC-content are large and high in maize genome, respectively. Nevertheless, the large amplitude of mutations at target site requires scrutiny when checking mutations at off-target sites and potential safety concerns.
Mon, 17 August 2020
ARTICLE | doi:10.20944/preprints202008.0357.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Striga infestation; Striga damage; yield loss; nitrogen application
Online: 17 August 2020 (10:08:51 CEST)
Low soil nitrogen status of savanna soils in Nigeria contributes to the persistent Striga hermonthica (Del.) Benth. infestation that limits maize production. The application of nitrogen fertilizer to Striga-resistant hybrids may reduce Striga infection and increase grain yields. This study assessed the performance of maize hybrids at low (30 kg ha-1) and high (120 kg ha-1) nitrogen application under natural infestation with Striga at Kafin Madaki and Tudun Wada in 2014 and 2015. Results showed that the application of nitrogen at 120 kg ha-1 reduced number of Striga plants by 59% compared to application at 30 kg N ha-1 in Kafin Madaki and by 21% in Tudun Wada. Compared to 30 kg N ha-1, the 120 kg N ha-1 rate also reduced Striga damage rating by 22% in Kafin Madaki and by 33% in Tudun Wada across the hybrids. Hybrids 8338-1 (5.3) and OBASUPER 1 (4.3) were the only entries with Striga damage rating greater than 4.5 (SDR > 4.5) when averaged across the nitrogen levels at both locations. Grain yield was 86 and 98% higher in Kafin Madaki and Tudun Wada, respectively when N was applied at 120 kg N ha-1 than at 30 kg N ha-1. The hybrids M1124-3 and M1227-14 produced grain yields that were significantly higher than those of the other hybrids in all locations. The hybrid 8338-1 produced the lowest grain yield across locations. Our results showed that, the application of 120 kg N ha-1 to Striga resistant maize hybrids will reduce Striga infection and increase grain yield.
Sat, 15 August 2020
ARTICLE | doi:10.20944/preprints202008.0347.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: L. plantarum subsp. plantarum; ETEC K88; antimicrobial; probiotics
Online: 15 August 2020 (09:50:52 CEST)
For screening excellent lactic acid bacteria (LAB) strains to inhibit Escherichia (E.) coli (ETEC) K88, inhibitory activities of more than 1100 LAB strains isolated from different materials and kept in the lab were evaluated in this study. Nine strains with inhibition zone at least 22.00 mm (including that of hole puncher 10.00 mm) and good physiological and biochemical characteristics identified by 16S DNA gene sequencing and recA gene multiple detection, were assigned to Lactobacillus (L.) plantarum subsp. plantarum (5), L. fermentum (1), L. reuteri (1), W. cibaria (1) and E. faecalis (1), respectively. As investigated for their tolerance abilities and safety, only strain ZA3 possessed high hydrophobicity and auto-aggregation abilities, had high survival rate in low pH, bile salt environment and GI fluids, sensitive to ampicillin, resistant to norfloxacin and amikacin, without hemolytic activity and didn’t carry antibiotic resistance genes, exhibited broad spectrum activity against a wide range of microorganisms, and antibacterial substance may attribute to organic acids, especially lactic acid and acetic acid. The results indicated that the selected strain L. plantarum subsp. plantarum ZA3 could be considered a potential probiotic to inhibit ETEC K88 for further research.
Wed, 12 August 2020
ARTICLE | doi:10.20944/preprints202008.0287.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: grapevine; winter pruning; root distribution; root density; root growth; root/canopy ratio; root/yield ratio
Online: 12 August 2020 (13:31:36 CEST)
As in any other plant, in the grapevine roots play a vital role in terms of anchorage, uptake of water and nutrients, as well as storage and production of chemicals. Their behaviour and development depend on various factors, namely rootstock genetics, soil physical and chemical features, field agronomic practices. Canopy management, involving techniques such as defoliation and pruning, could greatly influence root growth. To date, most of the studies on grapevine winter pruning have focused on the effects on yield and quality of grapes, achievable by using different pruning systems and techniques, while the knowledge of root distribution, development, and growth in relation to winter pruning is still not well understood. In this contest, the purpose of this study was to investigate the effect of winter pruning on the root system of field-grown Vitis vinifera cv. Pinot Gris grafted onto rootstock SO4. We compared two pruning treatments (pruning-P and no pruning-NP) and analysed the effect on root distribution and density, root index and on the root sugar reserves. Root data were analysed in relation to canopy growth and yield, to elucidate the effect of winter pruning on the root/yield ratio. Our data indicated that winter pruning stimulated the root growth and distribution without compromising canopy development, while no-pruning treatment produced less growth of roots but a larger canopy. Information regarding root growth and root canopy ratio is important as it gives us an understanding of the relationship between the aerial and subterranean parts of the plant, how they compete, and finally, offers us the possibility to ponder on cultural practices.
REVIEW | doi:10.20944/preprints202008.0286.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Elevated CO2; Drought; Photosynthesis; Transpiration rate; Stomatal conductance
Online: 12 August 2020 (13:27:02 CEST)
The changing dynamics in climate is the primary and important determinant of agriculture productivity. The effects of this changing climate on overall productivity in agriculture can be understood when we study the effects of individual components contributing to the changing climate on plants and crops. Elevated CO2 and drought due to low variability in rainfall is one of the important manifestations of the changing climate. There is considerable amount literature that addresses these aspects in terms of effects on plants systems from molecules to ecosystems. Of particular interest is the effect of increased CO2 on plants in relation to drought and water stress. As it is known that one of the consistent effects of increased CO2 in the atmosphere is increased photosynthesis, especially in C3 plants, it will be interesting to know the effect of drought in relation to elevated CO2. The possible mechanisms by which this occurs will be discussed in this minireview. Interpreting the effects of short term and long term exposure of plants to elevated CO2 in context of ameliorating the negative impacts of drought will show us the possible ways by which there can be effective adaption to crops in the changing climate scenario.
Mon, 10 August 2020
REVIEW | doi:10.20944/preprints202008.0233.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: lignocellulosic substrate; pre-treatment; microalgae/cyanobacteria; biogas; problems; animal feed
Online: 10 August 2020 (03:46:14 CEST)
Modern day civilization is dependent on energy generation by fossil fuels. But the major drawback of using fossil fuels is environmental pollution. Microalgae are potential candidate for production of various products of interest, such as proteins, mini food, pigments and triglycerides that can be converted into biofuels. Lignocellulosic feedstocks are the most abundantly available raw material of plants that can serve as a promising feedstock for cultivating bacteria, fungi, yeasts and microalgae to produce biofuels and other value-added products. Owing to the abundant availability of these low/no cost substrates, can be utilized as feedstocks for cultivating microalgae to generate biogas/biodiesel. Likewise, there is much room to exploit defatted algal biomass to be used as animal/fish feed and oil producing/accumulating genes knowledge in future to produce high and good quality biodiesel and biogas.
ARTICLE | doi:10.20944/preprints202008.0232.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Brassica yellows virus (BrYV); Myzus persicae; transgenic plants with BrYV full length genome; frozen BrYV infected plants; acquisition and transmission
Online: 10 August 2020 (03:34:00 CEST)
Brassica yellows virus (BrYV) is a tentative species of the genus Polerovirus, which occurs widely and mostly damage Brassicaceae plants in East Asia. Since BrYV could not be transmitted mechanically, an insect transmission method is required for further virus research. Here, a reliable and unrestricted method was described, in which non-viruliferous aphids (Myzus persicae) acquired BrYV from transgenic Arabidopsis thaliana plants with virus full length genome germinated from seeds and frozen infected leaves were used to transmit the virus to healthy plants, and there was no significant difference in acquisition rate though transmission rate from frozen infected leaves was somehow lower compared to fresh infected leaves. This novel simple method could be applied to preservation of virus inocula, evaluation of variety resistance to BrYV, biological research on interaction among BrYV, aphid and host, which also provide a new idea on establishing a basic method using virus genomic transgenic plants or frozen infected leaves for other poleroviruses research.
Sun, 2 August 2020
ARTICLE | doi:10.20944/preprints202008.0010.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: ascorbate; ascorbate-glutathione cycle; capsaicin; catalase; dihydrocapsaicin; glutathione; NADP-dehydrogenases; superoxide dismutase
Online: 2 August 2020 (10:52:06 CEST)
Capsicum is the genus where a number of species and varieties have pungent features due to the exclusive content of capsaicinoids such as capsaicin and dihydrocapsaicin. In this work, the main enzymatic and non-enzymatic systems in pepper fruits from four varieties with different pungent capacity has been investigated at two ripening stages. Thus, a sweet pepper variety (Melchor) from California type fruits, and three autochthonous Spanish varieties were used, including Piquillo, Padrón and Alegría riojana. The capsaicinoids contents were determined in pericarp and placenta from fruits showing that these phenyl-propanoids were mainly localized in placenta. The activity profile of catalase, superoxide dismutase (SOD, total and isoenzymatic), the enzymes of the ascorbate-glutathione cycle (AGC) and four NADP-dehydrogenases indicate that some interaction with the capsaicinoid metabolism seems to occur. Among the results obtained on enzymatic antioxidant, the role of an Fe-SOD and the glutathione reductase from the AGC is highlighted. Additionally, it was found that ascorbate and glutathione content were higher in those pepper fruits which displayed the greater contents of capsacinoids. Taken together, all these data indicate that antioxidants may contribute to preserve capsaicinoids metabolism to maintain their functionality in a framework where NADPH is perhaps playing an essential role.
Fri, 31 July 2020
ARTICLE | doi:10.20944/preprints202007.0726.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Carboxymethylcellulose; Pectin; Plum; Qualitative attributes; Enzymatic activity; Postharvest
Online: 31 July 2020 (03:04:33 CEST)
Polysaccharide-based edible coatings are served as an attractive preservation method for postharvest maintenance of most fruits. The current study examined the effect of carboxymethylcellulose (CMC)- and pectin (Pec)- based edible coatings on weight loss, firmness, total soluble solids (TSS), pH¬, titratable acidity (TA), vitamin C (vit C), total phenolics, anthocyanin and flavonoid contents, total antioxidant capacity (based on DPPH) and the activities of peroxidase (POD), polyphenol oxidase (PPO) and polygalacturonase (PG) enzymes during cold storage. The results showed that each coating and their combinations caused positive effects in all measured parameters except weight loss. The applied coatings preserved firmness and improved total phenols, anthocyanin and flavonoid contents, antioxidant capacity and POD activity. In addition, the coatings retarded TSS and pH enhancement and TA and vit C loss and decreased PPO and PG activities. It could be stated that CMC at 1 % and Pec at 1.5 % separately demonstrated the best results at most measured parameters; and among the combinations 0.5 % Pec + 1.5 % CMC acted better than the other treatments. Henceforth, application of CMC and/or Pec and/or their combinations would be considered as favorable approaches to improve postharvest quality characteristics of plum fruit.
Thu, 30 July 2020
Subject: Biology, Agricultural Sciences & Agronomy Keywords: weed management; integrated tillage; integrated mowing; herbicide; biodiversity and fruit production
Online: 30 July 2020 (12:19:14 CEST)
Despite the productivity, achieving long-term sustainability and maintaining plant biodiversity become the pivotal goals in orchard floor management, especially along tree rows. Thus, the paradigm of eradicating weeds in the tree row using chemical herbicide or repeated soil tillage needs to be substituted with more sustainable alternatives. This study was conducted in two commercial apple and peach orchards in Marche region (Italy). Two integrated mechanical approaches, integrated mowing (mower + brush or disc) and integrated tillage (blade weeder + integrated mowing), were compared with standard herbicide system in a 2-years trial. Weed species abundance, soil coverage rate, and weed biomass productions, including gas exchange parameters, tree growth, fruit yield and quality were measured. Both integrated practices had significant effects on the number of weed species, total vegetation coverage, and dry weed biomass production. No significant differences were found in terms of tree gas exchange parameters, growth and fruit yield. However, a few fruit quality parameters such as fruit firmness, solid soluble content and dry matter content responded positively to the integrated practices. These results suggest that the integrated mechanical approaches of weed management increased orchard biodiversity, and they had no adverse effects on tree growth, fruit yield, and quality.
Tue, 28 July 2020
ARTICLE | doi:10.20944/preprints202007.0677.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: conservation agriculture; compost; soil quality; bio-test; macro- and micronutrients; free-living nematodes; microbial respiration; microbial biomass
Online: 28 July 2020 (10:31:47 CEST)
Reduced nutrient mineralization rates under minimum tillage are usually compensated by mineral fertilizer application. These cannot be applied in organic farming systems, however. We hypothesized that organic minimum tillage based on frequent cover cropping and application of dead mulch will improve soil fertility and can compensate for the potential negative effects of minimum tillage. Two long-term field experiments were set up in 2010 and 2011 comparing plough versus minimum tillage including application of transferred mulch. As second factor, the application of compost versus mineral potassium and phosphorus was compared. In 2019, soils were analyzed for soil pH, organic carbon, macro-, micronutrients, microbial biomass, microbial activity and total nematode abundance. In addition, performance of pea in the same soils was determined under greenhouse conditions. Across both experiments, macronutrients (+52%), micronutrients (+11%), microbial biomass (+51%), microbial activity (+86%), and bacterivorous nematodes (+112%) increased in minimum tillage compared with the plough-based system. In the greenhouse, pea biomass was 45% higher in the soil that had been subjected to minimum tillage compared to the plough. In conclusion, soil fertility can be improved in organic minimum tillage systems by intensive cover cropping and application of dead mulch to levels higher than in a plough-based system.
Fri, 24 July 2020
ARTICLE | doi:10.20944/preprints202007.0584.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Bio-organic fertilizer; Bio-chemical fertilizer; Grain yield; N-Fixer
Online: 24 July 2020 (13:46:30 CEST)
The aim of the present study was to assess the efficacy of All Cosmos Industries (ACI) bio-organic and bio-chemical fertilizers and ACI N-Fixer (N-Bio Booster) on the paddy yields based on the field trial plots at Langkat, Medan, Indonesia. This application of ACI bio-organic fertilizer (NPK 5/5/5) and ACI bio-chemical (NPK 15/15/15) fertilizer and ACI N-Fixer tests were conducted at the paddy farm at Langkat from May-October 2018. This study employed a factorial randomized complete block design which consisted of two factors, namely: Factor I with four types of fertilizers while Factor II consisted of two paddy varieties (Inpari 30 and Inpari 32). Overall, the filled grains in the ACI treatments are significantly (P< 0.05) higher than those in the control treatments that used Normal Chemical Compound NPK. Overall, total weight per meter² (368-617g) in ACI treatments are also significantly (P< 0.05) higher than those (319-371g) in the control treatments. At harvesting time at 105 days after transplanting, significantly higher (P< 0.05) colony counts (13-15 x 106 CFU/mL) (for ACI treatments), than those (8 x 106 CFU/mL) in the controls positively indicated higher total yields of paddy grains per hectare. It was found that the application of ACI bio-organic and bio-chemical fertilizers and ACI N-Fixer can improve paddy yields of the two rice varieties, between 16.4-38.2% (up to 5.75 MT/ha), in the field trial plots at Langkat. These commercial fertilizers play an imperative role in refining the soil fertility and thereby can increase the yield of rice production. Therefore, it is highly recommended that ACI bio-organic and ACI bio-chemical fertilizers and ACI N-Fixer (N-Bio Booster) can be employed to increase the paddy yield in this region.
Thu, 23 July 2020
ARTICLE | doi:10.20944/preprints202007.0535.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: agricultural land; remote sensing; agricultural fire; fire predicting model
Online: 23 July 2020 (08:00:53 CEST)
Agricultural land fires have been linked to various and adverse impacts on ecosystems, food security and the agriculture sector. Understanding the patterns and drivers of agricultural land fires is essential for effective agricultural land fire management. The key objectives of this study were to (1) analyze the temporal and spatial patterns of agricultural land fires using satellite remote sensed data, (2) assess a range of environmental conditions that could drive the occurrence of agricultural land fires, (3) determine the best model for predicting agricultural land fires and (4) determine the relative contribution of each environmental condition variable on the best predictive model. We used both univariate and multivariate regressions for the fire prediction capability of four independent environmental conditions (fuel, weather, topographic and anthropogenic). Analysis of historical satellite data revealed that agricultural land fires were more frequent than forested land fires. Our analyses also revealed that fuel condition was the most important variable for predicting agricultural land fires followed by weather, topographic and anthropogenic conditions. This study provides a novel multivariate model for predicting agricultural land fires that harbors the potential to improve agricultural land fire management and reduce fire risk within the agricultural sector.
Wed, 22 July 2020
ARTICLE | doi:10.20944/preprints202007.0512.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: RTE salads; Microbiological quality; shelf-life; MBS method
Online: 22 July 2020 (10:09:19 CEST)
The market of ready-to-eat salads is experiencing a noticeable growth in Europe. The commercial success of these products is linked to the growing demand for fresh, healthy and nutritionally valuable products that can be consumed without preparation time and are perceived as safe and very high-quality products. Since they are intended to be consumed without additional treatments, these ready-to-eat products are associated with a high microbiological risk. The aim of this work was to evaluate the microbiological quality and safety of ready-to-eat salads sold in widespread supermarket chains in Lazio, Italy, at the packaging date, during shelf-life and during home-refrigeration. The study also aimed to determine the differences between low, medium and high cost products. Salmonella spp., L. monocytogenes were chosen as safety indicators as specified by European regulations while total aerobic mesophilic bacteria and Escherichia coli were chosen as quality indicators as suggested by national guidelines. Analyses were performed following the ISO standards and in parallel, for the evaluation of total aerobic mesophilic bacteria, with an alternative colorimetric system, the MBS method, in order to propose a simple, affordable and accurate alternative for testing the microbiological quality of products, especially suitable for small and medium enterprises and on-site analyses.
Fri, 17 July 2020
CONCEPT PAPER | doi:10.20944/preprints202007.0390.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Farmer’s right; food sovereignty; seed production system; conventional breeding
Online: 17 July 2020 (15:22:09 CEST)
Farmer’s right and their sovereignty is an important issue related with intellectual property rights and agrobiodiversity management. To boost farmer’s right, a conceptual hypothesis is proposed where they choose either a new high yielding variety or the existing one and apply conventional breeding approaches to select the seed for next years in their own fields. Although farmers produce seeds traditionally from several years, they have not been guided with scientific discipline to produce sufficient amount of quality seeds. This new concept suggests trained farmers can use breeding approaches to produce quality seed for their own use.
Thu, 16 July 2020
REVIEW | doi:10.20944/preprints202007.0355.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Colletotrichum truncatum; Colletotrichum gloeosporioides; chilli anthracnose; polymerase chain reaction assay; disease distribution
Online: 16 July 2020 (13:13:10 CEST)
This paper reviews the current knowledge of pepper anthracnose in the Philippines. We present research outputs on pepper anthracnose from the last three years. Then, we present evidence of the widespread occurrence of C. acutatum sensu lato in the Philippines. Finally, we highlight some research prospects that would contribute towards developing an integrated anthracnose management program.
Wed, 15 July 2020
ARTICLE | doi:10.20944/preprints202007.0336.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Prediction accuracy; Mixed linear and Bayesian models; Machine learning algorithms; Training set size and composition; Parametric and nonparametric models
Online: 15 July 2020 (12:13:40 CEST)
Genomic selection (GS) can accelerate variety release by shortening variety development phase when factors that influence prediction accuracies (PA) of genomic prediction (GP) models such as training set (TS) size and relationship with the breeding set (BS) are optimized beforehand. In this study, PAs for the resistance to fall armyworm (FAW) and maize weevil (MW) in a diverse tropical maize panel composed of 341 double haploid and inbred lines were estimated. Both phenotypic best linear unbiased predictors (BLUPs) and estimators (BLUEs) were predicted using 17 parametric, semi-parametric, and nonparametric algorithms with a 10-fold and 5 repetitions cross-validation strategy. n. For both MW and FAW resistance datasets with an RBTS of 37%, PAs achieved with BLUPs were at least as twice as higher than those realized with BLUEs. The PAs achieved with BLUPs for MW resistance traits: grain weight loss (GWL), adult progeny emergence (AP), and number of affected kernels (AK) varied from 0.66 to 0.82. The PAs were also high for FAW resistance RBTS datasets, varying from 0.694 to 0.714 (for RBTS of 37%) to 0.843 to 0.844 (for RBTS of 85%). The PAs for FAW resistance with PBTS were generally high varying from 0.83 to 0.86, except for one dataset that had PAs ranging from 0.11 to 0.75. GP models showed generally similar predictive abilities for each trait while the TS designation was determinant. There was a highly positive correlation (R=0.92***) between TS size and PAs for the RBTS approach while, for the PBTS, these parameters were highly negatively correlated (R=-0.44***), indicating the importance of the degree of kinship between the TS and the BS with the smallest TS (31%) achieving the highest PAs (0.86). This study paves the way towards the use of GS for maize resistance to insect pests in sub-Saharan Africa.
REVIEW | doi:10.20944/preprints202007.0333.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Abiotic stress; Biotic stress; Adaptation; Climate change; Diaseases; Diversity; Genetic Resources; Gene bank; Wild relatives
Online: 15 July 2020 (11:21:07 CEST)
Abstract: A large number of collecting expeditions were launched in regions of ‘centers of diversity’ and hundreds of thousands of sample have been collected and stored in gene banks as ‘genetic resources’. So far, only a small number of the samples have been evaluated for their biotic and abiotic stress tolerance. Now, their time to become useful has come. A new global phenomenon has arisen – climate change. The crop genetic resources and their wild progenitors that have survived countless years of changing environment during the last 11,000 years could harbor genes that may be useful under the new growing conditions and environmental factors thrown up by climate change and global warming. With the deployment of modern bio-engineering techniques selected genes or gene fragments can be transferred from genetic resources to modern varieties of crop plants to make them well-prepared to mitigate the effects of global warming and climate change. The latter is the most serious issue facing plant breeders today. New pests and diseases could affect crop production. These review paper discusses various impacts and issues as a result of this phenomenon and suggest ways to safeguard our most important crops through better management of crop plant genetic resources in the near future.
Tue, 14 July 2020
ARTICLE | doi:10.20944/preprints202007.0312.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Arbutus unedo L; biochemical assessment; antioxidant capacity; phenolic compounds; Morocco
Online: 14 July 2020 (13:41:53 CEST)
There are not many exhaustive works emphasizing the amount of genetic diversity among the strawberry tree (Arbutus unedo L.) genotypes in Morocco. This work aims to assess the biochemical composition of strawberry tree fruits, as well as to establish the variation of this composition among them. In this study, total phenols, total flavonoids, condensed and hydrolyzable tannins, total anthocyanins and free radical scavenging activity through ABTS were investigated in strawberry tree fruits. Furthermore, qualitative and quantitative analyses of individual phenolic compounds by high-performance liquid chromatography (HPLC) were carried out. Color parameters such as lightness (L*), Chroma (c*) and hue angle (h°) were also investigated. All studied variables showed highly significant differences among all samples with the exception of hydrolyzable tannins and chromatic coordinates. Total phenolics varied from 22.63 ± 1.74 to 39.06 ± 2.44 mg GAE/g dry wt, total flavonoids varied from 3.30 ± 0.60 to 8.62 ± 1.10 mg RE/g dry wt and total anthocyanins ranged between 0.12 ± 0.06 and 0.66 ± 0.15 mg cya-3-glu/100g dry wt. In addition, condensed and hydrolyzable tannins amounts were in the range of 10.41 ± 1.07 - 16.08 ± 1.50 mg TAE/g dry wt and 4.08 ± 2.43 - 6.34 ± 3.47 respectively. Moreover, the IC50 value (ABTS) ranged between 1.75 and 19.58 mg AAE/g dry wt. 17 phenolic compounds were detected in strawberry tree fruits. Gallocatechol and catechin were the most abundant phenolic compound. Matrix of correlations revealed signiﬁcant positive and negative correlations among variables particularly c*, a* and b*. Principal component analysis showed that the ﬁrst three components formed than 68% of the total inertia. The following variables gallic acid, protocatechuic, gallocatechin, gallic acid derivative, chlorogenic acid, syringic acid, ellagic acid derivative II, L* and h* were the most involved in the total variance explained. Hierarchical clustering classified samples into one main cluster, with a single branch. The results highlight a high biochemical diversity within studied strawberry genotypes, which is probably more genetically related
Sun, 12 July 2020
REVIEW | doi:10.20944/preprints202007.0264.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Saccharomyces cerevisiae; biosorption; milk; ICP-MS; isotherm; sensory evaluation
Online: 12 July 2020 (15:29:26 CEST)
This study aimed to evaluate the capacity of Saccharomyces cerevisiae for Cadmium absorption in Milk. Nowadays one of the most serious problems is heavy metals pollution. Applying microorgaisms as a novel biotechnology is so useful especially in foodstuffs. Among the biosorbents for heavy metals’ removal, Saccharomyces cerevisiae has got an increasing attention due to its popularity in food industry. In this regard, the effects of some important factors such as the initial metal concentration, biomass concentration and contact time on the biosorption capacity of Saccharomyces cerevisiae were studied. The biosorption was analyzed by the inductively coupled plasma mass spectrometer (ICP-MS). The maximum Cd bioremoval (70%) was at 80 μg/L of this metal concentration in milk samples containing 30×108 CFU Saccharomyces cerevisiae at the end of storage time (the 4th day). There were no significant differences in sensory and physicochemical properties of milk samples during storage (p < 0.05). The isotherm studies followed by two popular models; Langmuir and Freundlich and the results showed a better fit to the Langmuir isotherm. All together, the results of this project demonstrated that the approach of using this valuable yeast, could be applied for food and drinks’ detoxification and producing healthier foods.
Sat, 11 July 2020
ARTICLE | doi:10.20944/preprints202007.0218.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Solanum tuberosum; agroecosystems; high-throughput sequencing; fungal guild, fungal diversity; host specificity; potato cultivars
Online: 11 July 2020 (02:02:34 CEST)
The rhizosphere fungal community can play an important role in determining plant growth and health. In this study, using high-throughput sequencing, we investigated the fungal diversity and community composition in the roots and rhizosphere soil of 21 potato (Solanum tuberosum L.) cultivars. The samples were collected at three different sampling points. Furthermore, we assessed the differences in both diversity and composition of pathogen and saprotroph communities. In soil and roots, the fungal richness and relative abundance of pathogens and saprotrophs were mainly affected by sampling time. However, root fungal communities were also significantly affected by cultivar. The most substantial effect of cultivar was on root pathogen diversity. Moreover, the occurrence of most pathogens strongly varied among cultivars. Soil fungal community composition was primarily determined by sampling time; whereas in roots, the primary determinant was cultivar. Our results demonstrate changes in fungal communities over the potato growing season, as well as highlight the importance of potato cultivar on root fungal communities, and emphasise their importance in plant breeding.
Thu, 9 July 2020
ARTICLE | doi:10.20944/preprints202007.0166.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Apis mellifera; Varroa destructor; Mite non reproduction (MNR); Suppressed mite reproduction (SMR); Varroa sensitive hygiene (VSH); hygienic behaviour
Online: 9 July 2020 (05:21:22 CEST)
In the current context of worldwide honey bee colony losses, among which the varroa mite plays a major role, hope to improve honey bee health lies in part in the breeding of varroa resistant colonies. To do so, methods used to evaluate varroa resistance need better understanding. Repeatability and correlations between traits such as Mite Non-Reproduction (MNR), Varroa Sensitive Hygiene (VSH) and hygienic behaviour are poorly known, due to practical limitations and to their underlying complexity. We investigate (i) the variability, (ii) repeatability of the MNR score and (iii) its correlation with other resistance traits. To reduce the inherent variability of MNR scores, we propose to apply an Empirical Bayes correction. On the short-term (ten days) MNR had a modest repeatability of 0.4 whereas on the long- term (a month) it had a low repeatability of 0.2, similar to other resistance traits. Within our dataset there was no correlation between MNR and VSH. Although MNR is amongst the most popular varroa resistance estimates in field studies, its underlying complex mechanism is not fully understood. Its lack of correlation with better described resistance traits and low repeatability suggest that MNR need to be interpreted cautiously, especially when used for selection.
Sun, 5 July 2020
ARTICLE | doi:10.20944/preprints202007.0042.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: fitness; life table; cotton bollworm; corn earworm; toxin; resistance management
Online: 5 July 2020 (04:42:07 CEST)
Insecticidal toxins from Bacillus thuringiensis (Bt) are valuable tools for pest management worldwide, contributing to the management of human disease insect vectors and phytophagous insect pests of agriculture and forestry. Here, we report the effects of dual and triple Bt toxins expressed in transgenic cotton cultivars on the fitness and demographic performance of Helicoverpa zea (Boddie), a noctuid pest known as cotton bollworm and corn earworm. Life-history traits were determined for individuals of three field populations from a region where H. zea overwintering is likely. Triple-gene Bt cotton cultivars expressing Cry and Vip3Aa toxins killed 100% of the larvae in all populations tested. In contrast, dual-gene Bt cotton expressing Cry1Ac+Cry1F and Cry1Ac+Cry2Ab2 allowed population growth with the intrinsic rate of population growth (rm) 38% lower than on non-Bt cotton. The insects feeding on Bt cotton plants expressing Cry1Ac+Cry2Ab2, Cry1Ac+Cry1F, or Cry1Ab+Cry2Ae exhibited reduced larval weight, survival rate, and increased development time. Additionally, fitness parameters varied significantly among the insect populations, even on non-Bt cotton plants, likely because of their different genetic background and/or previous Bt toxin exposure. This is the first report of the comparative fitness of H. zea field populations on dual-gene Bt cotton after the recent reports of field resistance to certain Bt toxins. These results document the population growth rates of H. zea from an agricultural landscape with 100% Bt cotton cultivars. Our results will help to refine models designed to predict resistance evolution and improve insect resistance management for Bt crops.
Tue, 30 June 2020
ARTICLE | doi:10.20944/preprints202006.0361.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Emission; Turbulence; Roof slope; Scaled model; Wind tunnel; Dispersion
Online: 30 June 2020 (08:25:39 CEST)
The application of naturally ventilated pig buildings (NVPBs) with outdoor exercise yards is on the rise mainly due to animal welfare considerations, while the issue of emissions from the buildings to the surrounding environment is important. Since air pollutants are mainly transported by airflow, the knowledge on the airflow characteristics downwind the building is required. The objective of this research was to investigate airflow properties downwind of a NVPB with a roofed outdoor exercise yard for roof slopes of 5°, 15°, and 25°. Air velocities downwind a 1:50 scaled NVPB model were measured using a Laser Doppler Anemometer in a large boundary layer wind tunnel. A region with reduced mean air velocities was found along the downwind side of the building with a distance up to 0.5 m (i.e. 3.8 times building height), in which the emission concentration might be high. It was found that a smaller roof slope (i.e. 5° slope) resulted in a higher and shorter wake zone and thus a shorter air pollutant dispersion distance. It was concluded that a smaller roof slope could contribute to the dilution of air pollutants and a lower air pollutant concentration near the ground.
Fri, 12 June 2020
ARTICLE | doi:10.20944/preprints202006.0143.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: COVID-19; Corona virus; Aquatic food system; Food security; Small-scale fisheries; Bangladesh
Online: 12 June 2020 (08:25:09 CEST)
COVID-19 is now a major global health crisis, can lead to severe food crisis unless proper measures are not taken. Though a number of scientific studies have addressed the possible impacts of COVID-19 in Bangladesh on variety of issues, problems and food crises associated with aquatic resources and communities are missing. Therefore, this study aimed at bridging the gap in the existing situation and challenges of COVID-19 by linking its impact on aquatic food sector and small-scale fisheries with dependent population. The study was conducted based on secondary data analysis and primary fieldwork. Secondary data focused on COVID-19 overview and number of confirmed, recovered and death cases in Bangladesh; at the same time its connection with small-scale fisheries, aquatic food production, demand and supply was analyzed. Community perceptions were elicited to present how the changes felt and how they affected aquatic food system and small-scale fisheries and found devastating impact. Sudden illness, reduced income, complication to start production and input collection, labor crisis, transportation abstraction, complexity in food supply, weak value chain, low consumer demand, rising commodity prices, creditor’s pressure were identified as the primary affecting drivers. Dependent people felt the measures taken by the Government should be based on protecting the health and food security, although it could be detrimental to economic growth in the short term. The study provides insight into policies adopted by the policy makers to mitigate the effects of the pandemic on aquatic food sector and small-scale fisheries.
Tue, 9 June 2020
ARTICLE | doi:10.20944/preprints201909.0219.v2
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Systems Biology; Horticulture; Computational Biology; Complex System; Fertilization; System Modeling
Online: 9 June 2020 (04:04:16 CEST)
Differential equation models to understand interaction between plant and nutrient solution are presented. The root cells selectively emit H+ ions with active transport consuming ATPs to establish electrical gradient along the cell membrane. It establishes electrical field with Nernst potential to make positively charged ions outside the cell membrane flow into the root cell. Anion influx is also modulated by H+ ion concentration because plant root cell absorbs negatively charged particles with symport. If an anion collides with H+ cell to make net charge as neutral, at symport channel, it can flow through. In this paper, mathematical models for cation and anion absorption are introduced. Cation absorption model was induced from Ohm's law combined with Goldman's equation. Anion absorption model is similar to chemical reaction rate model. Both models have physiological terms influenced by gene expression pattern, species or phenotypes. Cation model also includes terms for ion's kinetic and electrical properties, growth of plant and interaction between the root and the surroundings. Simulation for 20 different sets of coefficients showed that the physiology-related coefficient has important role on nutrition absorption tendencies of plants.
Tue, 12 May 2020
Subject: Biology, Agricultural Sciences & Agronomy Keywords: rice; yield; HYV; Tongil; indica; japonica; SNP; molecular breeding
Online: 12 May 2020 (05:56:38 CEST)
The inter-subspecific crossing between indica and japonica subspecies in rice have been utilized to improve the yield potential of temperate rice. In this study, a comparative study of the genomic regions in the eight high-yielding varieties (HYVs) was conducted with those of the four non-HYVs. The Next-Generation Sequencing (NGS) mapping on the Nipponbare reference genome identified a total of 14 common genomic regions of japonica-originated alleles. Interestingly, the HYVs shared japonica-originated genomic regions on nine chromosomes, although they were developed through different breeding programs. A panel of 94 varieties was classified into four varietal groups with 38 single nucleotide polymorphism (SNP) markers from 38 genes residing in the japonica-originated genomic regions and 16 additional trait-specific SNPs. As expected, the japonica-originated genomic regions were only present in the japonica (JAP) and HYV groups, except for Chr4-1 and Chr4-2. The Wx gene, located within Chr6-1, was present in the HYV and JAP variety groups, while the yield-related genes were conserved as indica alleles in HYVs. The japonica-originated genomic regions and alleles shared by HYVs can be employed in molecular breeding programs to further develop the HYVs in temperate rice.
Tue, 5 May 2020
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Productivity; Wheat; Organic; Inorganic; FYM and Vermicompost
Online: 5 May 2020 (12:06:26 CEST)
Intensive cultivation and excess chemical fertilizer continuous tillage activity have shown that environmental, soil & water degradation in South Asia has produced serious problems in soil health or agricultural development with a rise in population. The desire for renewable alternatives has therefore been underestimated. The effect on cropping efficiency, machine productivity and development economy of two tillage cum (Vermicompost and FYM manure, Urea, and DAP) or two facts regarding the application of foliar spray and without zinc fertilizers were evaluated. Conventional tillage (1 ploughing by tractor drawn disc plough + 2 harrowing + 1 fb cultivator with planking) increased grain yield (10.85 percent) and (7.21), both during the first and second years of experimental plots, over minimum tillage (1 ploughing by tractor drawn rotavator) (MT). The improved grain output of wheat was primarily due to increased tiller development in CT treatments during both the years. Similarly, maximum most of the growth attributes, productivity components and physical quality charcters were recorded in CT tillage practice. In the joint management of inorganic or organic nitrogen, significant and maximum grain (4.63 t/ha) and straw (8.97 t/ha) yield, weight of spike (2.68 g), length of grain (6.49 mm), breadth of grain (3.29 mm) and length: breadth ratio of grain (1.98) were recorded during 2015-16, However purely chemical fertilizer applied treatment recorded during first year significant and maximum number of tillers per hill (3.14), leaf area index (2.31), plant dry matter (13.09 g plant-1), grain yield (4.00 t ha-1), straw yield (7.87 t ha-1), number of grains per spike (42.42) and weight of spike (2.62 g), respectively. Soil cultivation by CT with fertilized fertilizer at the prescribed total dose of nitrogen 120 kg/ha, in which ½ nitrogen through organic (Vermicompost 3000 kg/ha) and ½ through inorganic (Urea, 117.69 kg/ha and (Diammonium phosphate (DAP) 32.60 kg/ha) during second year with foliar applications of zinc (2.50 kg/ha) were found to increase crop productivity and resilience in management. Soil chemical quality status increased after second year of experiment in combined used of MT (1 ploughing by tractor drawn rotavator) and organic (Vermicompost 4500 kg/ha) and inorganic fertilization ½ through inorganic (Urea, 44.16 kg/ha and (Diammonium phosphate (DAP) 48.91kg/ha) with foliar applications of zinc (2.50 kg/ha).
Thu, 30 April 2020
Subject: Biology, Agricultural Sciences & Agronomy Keywords: rice; yield; HYV; Tongil; indica; japonica; SNP; molecular breeding
Online: 30 April 2020 (03:18:24 CEST)
The inter-subspecific crossing between indica and japonica subspecies in rice have been utilized to improve the yield potential of temperate rice. In this study, a comparative study of the genomic regions in the eight high-yielding varieties (HYVs) was conducted with those of the four non-HYVs. Next-Generation Sequencing (NGS) mapping on the Nipponbare reference genome identified a total of 14 common genomic regions of japonica-originated alleles. Interestingly, the HYVs shared the japonica-originated genomic regions on the nine chromosomes, although they were developed from different breeding programs. A panel of 94 varieties was classified into four varietal groups with 39 single nucleotide polymorphism (SNP) markers from 39 genes residing in the japonica-originated genomic regions and 16 additional trait-specific SNPs. As expected, the japonica-originated genomic regions were only present in the japonica (JAP) and HYV groups, except for Chr4-1 and Chr4-2. The Wx gene, located within Chr6-1, was present in the HYV and JAP variety groups, while the yield-related genes were conserved as indica alleles in HYVs. The japonica-originated genomic regions and alleles shared by HYVs can be employed in molecular breeding programs to further develop the HYVs in rice.
Tue, 28 April 2020
ARTICLE | doi:10.20944/preprints202004.0499.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: system archetypes; rice production; system dynamics; climate change; Indonesia rice
Online: 28 April 2020 (13:04:04 CEST)
Climate projections show that southern Indonesia such as West Nusa Tenggara is projected to experience a lower precipitation and higher temperatures. To date, research on climate change impact on Indonesian rice production yield is limited. As climate change is projected to decrease rainfall and to increase temperatures, this paper offers a qualitative analysis using system archetypes to understand the impacts of climate change on rice production. Two system archetypes are identified including Limits to Growth and Success to Successful. Both archetypes explain that rice production is hampered by high minimum temperature as photosynthesis output is decreased by increasing respiration. This paper shows that using a simple tool, system archetypes, we can describe the impacts of climate change on rice production. The outputs of this study such as a causal loop diagram and system archetypes can be a basis to develop a simulation model in understanding the impacts of climate change on main crops.
Fri, 24 April 2020
ARTICLE | doi:10.20944/preprints202004.0428.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: rice; yield; HYV; Tongil; indica; japonica; SNP; molecular breeding
Online: 24 April 2020 (07:37:40 CEST)
The inter-subspecific crossing between indica and japonica subspecies in rice have been utilized to improve yield potential in temperate rice. In this study, a comparative study of the genomic regions in the eight high yielding varieties (HYVs) was conducted with those of the four non-HYV varieties. NGS mapping on the Nipponbare reference genome identified a total of 14 common genomic regions of japonica-originated alleles. Interestingly, the HYVs shared the japonica-originated genomic regions on the nine chromosomes, although they were developed from different breeding programs. A panel of 94 varieties was classified into four varietal groups with the 39 SNP markers from 39 genes residing the japonica-originated genomic regions and 16 additional trait-specific SNPs. As expected, the japonica originated genomic regions were present only in JAP and HYV groups with exceptions for Chr4-1 and Chr4-2. The Wx gene located within Chr6-1 was present in HYV and JAP variety groups, while the yield-related genes were conserved as indica alleles in HYVs. The japonica-originated genomic regions and alleles shared by HYVs can be employed in molecular breeding programs for further development of HYVs in rice.
Tue, 7 April 2020
REVIEW | doi:10.20944/preprints202004.0105.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Mulberry fruit; phytochemicals; bioactive components; pharmacological properties
Online: 7 April 2020 (13:25:29 CEST)
Mulberry (Morus) cultivated worldwide in diverse agro-ecological conditions recognized as the fodder of silkworms (Bombyx mori). In India, ranging from high altitude Himalayan region to coastal region, the farmers generally cultivate these four species of mulberry (Morus alba, M. indica, M. serrata, and M. laevigata). Mulberry fruit is used in traditional medicine for several years in China and also consumed as food material in different countries of Asia and Africa. Mulberry fruit, along with high nutritious value, contains many bioactive phytochemicals that are30 of health benefits and can fight against many diseases. Many researchers attracted to this property of mulberry fruit, and they isolated bioactive polysaccharides, anthocyanins, flavonols, flavonols, phenolic acids, alkaloids, and melatonins. These compounds have antioxidant property and due to this, either in synergistically or in the pure form, these components have direct or indirect curative activity on diabetes, inflammation, tumor, hepatic diseases, immunomodulation, hyperlipidemia, neural damage, and chronic diseases. This tremendous bioactivity of mulberry fruit extract may open up a new dimension in the food and medicine industry. The present review provides recent findings of the phytochemical foundation and their bioactivities, which may encourage many researchers to explore the molecular mechanism of the biological activities which can be used for human welfare.
Wed, 18 March 2020
ARTICLE | doi:10.20944/preprints202003.0276.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: cover crop; cereal rye; hairy vetch; decomposition; Nitrogen release; exponential and hyperbolic models; Akaike Information Criterion
Online: 18 March 2020 (16:44:57 CET)
Empirical models help us understand the process of plant residue decomposition and nutrient release into the soil. The objective of this study was to determine an appropriate model to describe the decomposition of hairy vetch (Vicia villosa Roth) and cereal rye (Secale cereale L.) cover crop (CC) residue and nitrogen (N) release. Data pertaining to above and belowground CC residue mass loss and N release for up to 2633 cumulative decomposition degree days (112 d) after litterbag installation were obtained from two cropping system experiments, one conducted in 2015 and the other in 2017 and 2018 at the humid subtropical environment of southern IL, USA. Six exponential and two hyperbolic models were fit to percent mass and N remaining data to find the one with minimum Akaike Information Criterion (AIC) and residual sum of squares. Modified three-parameter single exponential and two- or three-parameter hyperbolic models best met the assumed criteria of selection for above and belowground CC residue, respectively. Fitting a double exponential model to a combined data for percent mass and N remaining, which identified two mass and N pools, a fast and a slow pool with different rate constants. A five-parameter double exponential with an asymptote met the preset criteria and passed all tests for normally distributed population, constant variance, and independence of residuals at α = 0.05 when fit to combined data of hairy vetch shoot mass and N remaining. However, a two-parameter hyperbolic and three-parameter asymptotic hyperbolic model provided the best fit to a combined data of cereal rye shoot mass and N remaining, respectively. Both hyperbolic decay models showed a good fit for belowground mass decomposition and N release for both CCs. Cereal rye had poorer fit than hairy vetch for mass and N remaining of both above and belowground mass. The best-selected decay models can be used to estimate the decomposition and N release rates of hairy vetch and cereal rye above and belowground residue in a similar environment.
Tue, 17 March 2020
REVIEW | doi:10.20944/preprints202003.0262.v1
Online: 17 March 2020 (03:13:58 CET)
For years chemical fertilizers are used to fulfill the soil requirement of nutrients and yield, but large amount of these chemical fertilizers are dangerous for environment, beneficial microbes, animals, and humans as well. Therefore, environmental friendly and cost effective biofertilizers are used. Biofertilizer are the substances which contain microorganisms those microorganisms may be fungi, bacteria, and protozoa which have ability to increase fertility of soil by Nitrogen fixation, Phosphorous solubilization, and Iron sequestration. These processes convert insoluble form of nutrients into soluble form and make it available to the roots of plant which easily take them up and utilize them. There are variety of the crops whose productivity can be increased by applying biofertilizer such as rice, oat, and other grain crops. In this review we go through the way of application of biofertilizers, and how the help the plants and in which they help.
Thu, 5 March 2020
ARTICLE | doi:10.20944/preprints202003.0093.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: net photosynthetic rate; key enzymes activity; starch pasting viscosity; yield
Online: 5 March 2020 (12:20:24 CET)
Rice-Tartary buckwheat is a special type of Tartary buckwheat with easy hulling thin shell. The local rice-Tartary buckwheat ‘cv. Xiaomiqiao’ (XMQ) was used to explore the characteristics of photosynthesis, starch synthesis, yield and quality, as compared to Tartary buckwheat ‘cv. Jinqiao 2’(JQ2). XMQ showed significantly lower values of net photosynthetic rate, ADPGase activity and starch synthase activity at one or more periods during grain filling, as compared to that of JQ2. The effective branch number and grain number per plant of XMQ were similar to that of JQ2 regardless of different years, but the 1000-grain weight was significantly lighter that resulted in the significantly lower yield. XMQ accumulated similar contents of starch (amylose, amylopectin) and protein (glutelin, albumin, prolamin, globulin) to that of JQ2, but exhibited significantly lower flavonoid content. The values of peak viscosity and hot paste viscosity in XMQ were similar to that of JQ2, but the values of cool paste viscosity, breakdown and setback were significantly lower. In conclusion, XMQ showed low yield due to the insufficient of photosynthesis and starch synthesis. XMQ exhibited high nutritional quality as well as normal Tartary buckwheat and stored 18.88mg g-1 of flavonoid, that can be consumed as daily diet. The present results will provide a basis for food processing and breeding of rice-Tartary buckwheat.
ARTICLE | doi:10.20944/preprints202003.0090.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: biostimulant; plant defence; mushrooms; antioxidant; septoriosis; wheat
Online: 5 March 2020 (12:08:56 CET)
The Septoria Leaf Blotch Complex (SLBC), caused by the two ascomycetes Zymoseptoria tritici and Parastagonospora nodorum, can reduce global yearly yield of wheat by up to 50%. In the last decade in Italy, SLBC incidence has increased; notably, durum wheat has proven to be more susceptible than common wheat. Field fungicide treatment can efficiently control these pathogens, but it leads to the emergence of resistant strains and adversely affects human and animal health, and the environment. Our previous studies indicated that active compounds produced by Trametes versicolor can restrict the growth of mycotoxigenic fungi and the biosynthesis of their secondary metabolites (e.g. mycotoxins). Specifically, we identified Tramesan: a 23 KDa -heteropolysaccharide secreted by T. versicolor that acts as a pro-antioxidant molecule in animal cells, fungi, and plants. Foliar-spraying of Tramesan (3.3 µM) in SLBC-susceptible varieties of durum significantly diminished symptoms of Stagonospora Nodorum Blotch (SNB) and Septoria Tritici Blotch (STB) by 75% and 65%, respectively. Tests were conducted under controlled conditions as well as in field. We show that Tramesan elicits wheat defence against SNB and STB augmenting the synthesis of defence-related hormones, notably JA and SA, that in turn switch on the expression of markers of defence (PR1, PR4 inter alia). In field experiments, yield of durum wheat plants treated with Tramesan was similar to that of untreated ones. The results suggest the use of Tramesan for protecting durum wheat against SLBC.
Sat, 29 February 2020
ARTICLE | doi:10.20944/preprints202001.0250.v2
Subject: Biology, Agricultural Sciences & Agronomy Keywords: fen; paludiculture; rewetting; drainage; matter fluxes; interdisciplinary
Online: 29 February 2020 (10:44:42 CET)
Of all terrestrial ecosystems, peatlands store carbon most effectively in long-term scales of millennia. However, many peatlands have been drained for peat extraction or agricultural use. This converts peatlands from sinks to sources of carbon, causing approx. 5% of the anthropogenic greenhouse effect and additional negative effects on other ecosystem services. Rewetting peatlands can mitigate climate change and may be combined with management in the form of paludiculture. Rewetted peatlands, however, do not equal their pristine ancestors and their ecological functioning is not understood. This holds especially for groundwater-fed fens. Their functioning results from manifold interactions and can only be understood following an integrative approach of many relevant fields of science, which we merge in the interdisciplinary project WETSCAPES. Here, we address interactions among water transport and chemistry, primary production, peat formation, matter transformation and transport, microbial community and greenhouse gas exchange using state of the art methods. We record data on six study sites spreading across three common fen types (Alder forest, percolation fen, and coastal fen) each in drained and rewetted state. First results showed that indicators reflecting more long-term effects like vegetation and soil chemistry showed a stronger differentiation between drained and rewetted state than variables with more immediate reaction to environmental change, like greenhouse gas (GHG) emissions. Variations in microbial community composition explained differences in soil chemical data as well as vegetation composition and GHG exchange. We show the importance of developing an integrative understanding of managed fen peatlands and their ecosystem functioning.
ARTICLE | doi:10.20944/preprints202002.0456.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: social farming; farming for health; inclusive model; migrants inclusion; ethics; innovation; social service; vulnerable people
Online: 29 February 2020 (08:55:22 CET)
The agricultural sector, even though it has been greatly reduced and is in constant transformation, continues to be of strategic importance. Although it does not represent a quantitatively relevant employment sector, the dynamics are interesting because they reflect the structural, economic and social transformations that are affecting the sector in recent years; there is a growing need for external labour that corresponds to a massive recourse of foreigners to work. Innovative approaches are required to explore the capacity of social farming to create a sustainable and inclusive workplace for migrant. The overall methodological approach of the paper seeks to synthesize fieldwork research and qualitative interviewing to validate the Italian inclusive model. To do this, we have selected four experiences of Italian social agriculture in which migrants are included.
Fri, 28 February 2020
ARTICLE | doi:10.20944/preprints202002.0435.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: encapsulated essential oils; coccidiosis vaccine; growth performance; broiler chickens; gut health
Online: 28 February 2020 (13:04:42 CET)
The present study was conducted to evaluate encapsulated essential oils as an alternative anticoccidial in coccidiosis vaccine challenged broiler chickens. A total of 600 day-old male broiler chicks were provided with no-added corn-soybean meal-based control diet or diets that contained either salinomycin or EO at 60 and 120 mg per kg of diet. On day 21, half of the control groups were orally challenged with a coccidiosis vaccine at 25 times higher than the recommended vaccine dose. During 22 to 28 days (i.e., one-week post coccidiosis vaccine challenge), the challenged chickens had decrease (P < 0.05) in body weight gain and feed intake but increase in feed conversion ratio compared with the non-challenged, naïve control chickens. However, dietary EO significantly counteracted (P < 0.05) coccidiosis vaccine-induced depression in body weight gain and feed intake. Increasing dietary EO linearly decreased (P < 0.05) the concentrations of the volatile fatty acids. Dietary SAL and EO affected gut morphology in chickens at 20 days posthatch. Increasing dietary EO linearly (P = 0.073) increased serum catalase activity. Collectively, our study shows that dietary EO increased coccidiosis vaccine-induced growth depression and altered gut physiology in broiler chickens.
Thu, 27 February 2020
ARTICLE | doi:10.20944/preprints202002.0409.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Agronomic traits; Hybrid performance; Nitrogen response; Plant density; Variability
Online: 27 February 2020 (15:59:14 CET)
Maize (Zea mays L.) production in West and Central Africa is constrained by drought, low soil-N and Striga infestation. Breeders in the region have developed and commercialized extra-early and early-maturing hybrids (E-EH and EH), which combine high yield potentials with tolerance/resistance to the three stresses. Hybrids of both maturity groups are new to the farmers; thus, the urgent need to recommend appropriate agronomic practices for these hybrids. We investigated the responses of four hybrids belonging to extra-early and early-maturity groups to plant density (PD) and nitrogen (N) application in five agroecologies. The EHs consistently out-yielded the E-EHs in all the five agroecologies. The hybrids showed no response to N-fertilizer application above 90 kg ha-1. All interactions involving N had no significant effect on all traits except in few cases. The E-EHs and EHs had similar response to PD; their grain yield decreased as PD increased. Contrarily, flowering was delayed and expression of some other agronomic traits such as plant and ear aspects became poorer with increased PD. Optimal yield was obtained at approximately 90 kg N ha-1 and 66,666 plants ha-1. Most of the measured traits indicated high repeatability estimates (i.e. ≥ 60) across the N levels, PDs and environments. Evidently, the hybrids were intolerant of high PD.
ARTICLE | doi:10.20944/preprints202002.0402.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: chromosome engineering; wheat breeding; Aegilops longissima; Thinopyrum ponticum; gluten quality; yield; leaf rust; stem rust; powdery mildew
Online: 27 February 2020 (11:29:25 CET)
If genetic gains in wheat yield are to be achieved in today’s breeding, increasing genetic variability of cultivated genotypes is an essential requisite to meet. To this aim, alien gene transfer through chromosome engineering (CE) is a validated and sound strategy. Attempts to incorporate more than one alien segment into cultivated wheat have been rare, particularly for tetraploid durum wheat. Here we present the agronomic and quality performance of the first successful CE-mediated multiple introgression into the latter species. By assembling into 7AL, 3BS and 1AS arms of a single genotype homoeologous segments of Thinopyrum ponticum 7el1L, Aegilops longissima 3SlS, and Triticum aestivum 1DS arms, respectively, we have stacked several valuable alien genes, comprising Lr19+Sr25+Yp (leaf and stem rust resistance and a gene increasing semolina yellowness), Pm13 (powdery mildew resistance) and Gli-D1/Glu-D3 (genes affecting gluten properties), respectively. Advanced progenies of single, double and triple recombinants were field-tested across three years in a typical durum wheat growing area of Central Italy. The results showed that not only all recombinants had normal phenotype and fertility, but also that one of the triple recombinants had the highest yield through all seasons compared with all other recombinants and control cultivars. Moreover, the multiple introgressions enhanced quality traits, including gluten characteristics and semolina yellow index. Presence of effective disease resistance genes confers additional breeding value to the novel and functional CE products, which can greatly contribute to crop security and safety.
Mon, 24 February 2020
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Hybrid machine learning; artificial neural networks; imperialist competitive algorithm; gray wolf optimization; crop yield
Online: 24 February 2020 (14:00:43 CET)
Prediction of crop yield is essential for food security policymaking, planning, and trade. The objective of the current study is to propose novel crop yield prediction models based on hybrid machine learning methods. In this study, the performance of artificial neural networks-imperialist competitive algorithm (ANN-ICA) and artificial neural networks-gray wolf optimizer (ANN-GWO) models for the crop yield prediction is evaluated. According to the results, ANNGWO, with R of 0.48, RMSE of 3.19, and MEA of 26.65, proved a better performance in the crop yield prediction compared to the ANN-ICA model. The results can be used by either practitioners, researchers or policymakers for food security.
Mon, 17 February 2020
ARTICLE | doi:10.20944/preprints202002.0249.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Fungal diversity; Saccharomyces; genetic diversity; glyphosate-based herbicides; copper-based fungicides; RoundUp Ready™ corn; phylogenetics
Online: 17 February 2020 (15:37:11 CET)
Saccharomyces cerevisiae are a phenotypically diverse species that adapt to a wide variety of environments by exploiting standing genetic diversity and selecting for advantageous mutations. Glyphosate and copper-based herbicides/ fungicides affect non-target organisms, these incidental exposures can impact microbial populations. In this study, glyphosate resistance was found in the historical collection of yeast which was collected over the last century, but only in yeast isolated after the introduction of glyphosate. The highest glyphosate-resistant yeasts were isolated from agricultural sites. However, herbicide application at these sites was not recorded. In an effort to assess glyphosate resistance and impact on non-target microorganisms, yeast were harvested from 15 areas with known herbicidal histories, including an organic farm, conventional farm, remediated coal mine, suburban locations, state park, and a national forest. Yeast representing 23 genera were isolated from 237 samples of plant, soil, spontaneous fermentation, nut, flower, fruit, feces, and tree material samples. Saccharomyces, Candida, Metschnikowia, Klyveromyces, Hanseniaspora, and Pichia were other genera commonly found across our sampled environments. Managed areas had less species diversity and at the brewery, only Saccharomyces and Pichia were isolated. A conventional farm growing RoundUp Ready™ corn had the lowest phylogenetic diversity and the highest glyphosate resistance. The mine was sprayed with multiple herbicides including a commercial formulation of glyphosate; however, the yeast did not have elevated glyphosate resistance. In contrast to the conventional farm, the mine was exposed to glyphosate only one year prior to sample isolation. Glyphosate resistance is an example of the anthropogenic selection of nontarget organisms.
Sat, 15 February 2020
ARTICLE | doi:10.20944/preprints202002.0202.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Napier grass; elephant grass; EMBRAPA; forage yield; feed quality; marker trait association
Online: 15 February 2020 (15:01:37 CET)
The evaluation of forage crops for adaptability and performance across production systems and environments is one of the main strategies used to improve forage production. To enhance the genetic resource base and identify traits responsible for increased feed potential of Napier grass, forty-five genotypes from EMBRAPA, Brazil, were evaluated for forage biomass yield and feed nutritional quality in a replicated trial under wet and dry season conditions in Ethiopia. The results revealed significant variation in forage yield and feed nutritional qualities among the genotypes and between the wet and dry seasons. Feed fibre components were lower in the dry season while crude protein, in vitro organic matter digestibility and metabolizable energy were higher. Based on the cumulative biomass yield and metabolizable energy yield, top performing genotypes were identified that are candidates for future forage improvement studies. Furthermore, the marker-trait association study identified diagnostic SNP and SilicoDArT markers and potential candidate genes that could differentiate high biomass yielding and high metabolizable energy genotypes in the collection.
Mon, 10 February 2020
Subject: Biology, Agricultural Sciences & Agronomy Keywords: soybean (Glycine max L.); NPQ; photoinhibition; bioinformatics; subcellular localization; qRT-PCR
Online: 10 February 2020 (09:47:05 CET)
Soybean (Glycine max L.) is an important crop that serves as a source of edible oil and protein. However, little is known about its molecular mechanism of adaptation to extreme environmental conditions. Based on the Arabidopsis thaliana sequence database and Phytozome, a soybean gene that was highly homogenous with the reduced induction of the non-photochemical quenching2 (AtRIQ2) gene, GmRIQ2-like (accession NO.: Glyma.04G174400), was identified in this study. The gene structure analysis revealed that GmRIQ2-like encoded a transmembrane protein. Elements of the promoter analysis indicated that GmRIQ2-like participated in the photosynthesis and abiotic stress pathways. The subcellular localization results revealed that the protein encoded by GmRIQ2-like was located in chloroplasts. The quantitative real-time (qRT)-PCR results revealed that GmRIQ2-like-overexpression (OE) and -knock-out (KO) transgenic soybean seedlings were cultivated successfully. The relative chlorophyll (Chl) and zeaxanthin contents and Chl fluorescence kinetic parameters demonstrated that GmRIQ2-like dissipated excess light energy by enhancing the non-photochemical quenching (NPQ) and reduced plant photoinhibition. These results suggested that GmRIQ2-like was induced in response to strong light and depressed Chl production involved in soybean stress tolerance. These findings indicate that the transgenic seedlings of GmRIQ2-like could be used to enhance strong light stress tolerance and protect soybean plants from photoinhibition damage. This study will serve as a reference for studying crop photoprotection regulation mechanisms and benefits the research and development of new cultivars.
Thu, 6 February 2020
ARTICLE | doi:10.20944/preprints202002.0080.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Vermicompost; Sesamum indicum L.; Perionyx excavates; NPK Fertilizers; Farm yard Manure; plant growth components
Online: 6 February 2020 (09:05:32 CET)
This paper aims in studying the effect of vermicompost on soil and growth of the plant Sesamum indicum L. by measuring the its various growth and yield components. For this purpose, a mixture of textile mill sludge, cow dung and saw dust have been mixed in different ratios to produce vermicompost by using the earthworm Perionyx excavates and was compared with inorganic (NPK) and organic fertilizer (FYM). The results of soil quality revealed that the porosity, water holding capacity (WHC), cation exchange capacity (CEC) and occurrence of macronutrients were significantly increased and the particle density were decreased in treatment with 100% vermicompost (VC) followed by soil treated with 50% VC + 50% NPK, on contrary, reduction in porosity, WHC, CEC were noted in NPK treated plots. The effect of vermicompost on plant growth components (root, shoot, leaf area index, branch, DMP) and yield components (pod number, weight, length, seed weight, number of seed, seed yield) were significantly higher in the plots treated with 50% VC + 50% NPK followed by 100% vermicompost than the plots treated only with FYM and NPK. The significant growth upon using vermicompost was accounted by its nutrients composition over other fertilizers.
Fri, 31 January 2020
ARTICLE | doi:10.20944/preprints202001.0380.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: barley; sowing date; seed rate; row spacing; yield
Online: 31 January 2020 (05:21:36 CET)
The precise information regarding the date of sowing, seed rate and row spacing is critical for achieving yield targets and better economic returns of barley. Therefore here, we determined the information regarding the optimum date of sowing, seed rate, spacing and economic aspects for barley production. This study was conducted for three years, in north Indian plains. Early sowing date of barley (last week of October) recorded higher yield in comparison to late sown crop (3rd week of November). Moreover, the higher barley production proved more remunerative when sown early in the last week of October to the first week of November as compared to late sown the late sown crop. Furthermore, the enhanced seed rate of 10% then recommended did not affect the grain yield of barley. But, the closer spacing of 20 cm (row to row) produced higher grain yield (5.45 Mg ha-1 ) than the recommended spacing of 22.5 cm (5.30 Mg ha-1). Likewise, the economical parameters (net returns) were higher with 20 cm row spacing. Overall, this study determines the optimum date of sowing, seed rate and spacing for scoring better returns of barley crop under north Indian conditions.
Tue, 28 January 2020
REVIEW | doi:10.20944/preprints202001.0332.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: transcriptomics; aquaculture; genetics; next generation sequencing
Online: 28 January 2020 (05:10:55 CET)
New challenges arise in the face of global climate change which impact every ecosystem on earth, including aquatic systems. This is evident in observations made in regard to the world’s oceans, which show trends of incremental changes in ocean surface temperatures, sea levels, and ocean acidity. These environmental shifts impact human resources such as fisheries and aquaculture. In addition, according to the World Bank, the increase in human population will also require more food and nutrient production, which include industries such as aquaculture. With this increasing demand in aquaculture and fisheries, we must develop efficient and productive methods to operate these industries. We can use genetic methods, specifically transcriptomic information to better understand the biology of our source of nutrition. With the advent of RNASeq techniques, we can provide a better understanding about growth and development, immune function and stress, and adaptations. The use of population genetics or (genomics) to detect Single Nucleotide Polymorphisms (SNPs) between populations or closely related species can provide greater insight from stock structure to fishery-induced evolution. In addition, candidate loci can be investigated further to better understanding evolutionary processes, which provide clues on physiological adaptations and gene expression patterns that can help elucidate how these organisms respond to their current environment. In addition, the use of transcriptomic analyses such as differential gene expression can be used to determine resilience in various environmental conditions such as pollution, hypoxic/anoxic conditions, fluctuations in salinity, and temperature extremes. There has been an increase in transcriptomic studies for many aquaculture species, which has aimed at improving our understanding of growth, development, and metabolism, providing vital information for fisheries and aquaculture industries to make adjustments to environmental conditions such as oxygen availability, nutrition, and salinity. All of these aspects provide insightful information for advancing our knowledge of aquaculture, fisheries and conservation management.
Mon, 27 January 2020
ARTICLE | doi:10.20944/preprints202001.0321.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: late blight; mating type; mefenoxam; metalaxyl; potato; SSR genotyping; race structure; tomato
Online: 27 January 2020 (07:28:44 CET)
Late blight caused by the oomycete pathogen Phytophthora infestans is a devastating disease of potato and tomato worldwide, including Israel. The population structure of this pathogen was monitored in potato and tomato fields in Israel during a 36-year period of 1983-2019. Isolates of the pathogen were tested for sensitivity to phenylamide fungicides, mating type, race structure, and genotype. The phenotypic and genotypic structure of the population from potato have changed greatly from one year to another, from one season to the next, within a season and within a single field. Major changes also occurred in the population collected from tomato crops. The mechanisms driving these multiple changes and the heterogeneous nature of the population in Israel are shown to derive from multiple migration events of the pathogen via seed tubers from Europe and from fitness-driven selection processes.
Wed, 22 January 2020
ARTICLE | doi:10.20944/preprints202001.0250.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: fen; paludiculture; rewetting; drainage; matter fluxes; interdisciplinary
Online: 22 January 2020 (02:48:40 CET)
Of all terrestrial ecosystems, peatlands store carbon most effectively. However, many peatlands have been drained for peat extraction or agricultural use. This converts peatlands from sinks to sources of carbon, causing approx. 5% of the anthropogenic greenhouse effect and additional negative effects on other ecosystem services. Rewetting peatlands can mitigate the climate crisis and may be combined with management in the form of paludiculture. Rewetted peatlands, however, do not equal their pristine ancestors and their ecological functioning is not understood. This holds especially for fens. Their functioning results from complex interactions and can only be understood following an integrative approach of many relevant fields of science, which we develop in the interdisciplinary project WETSCAPES. Here, we introduce our approach in which we are addressing interactions among water transport and chemistry, primary production, peat formation, matter transformation and transport, microorganisms and greenhouse gas exchange using state of the art methods in the relevant research fields. We record data on six study sites spreading across three important fen types (Alder forest, percolation fen, and coastal fen) each in drained and rewetted state. Using exemplary results, we show the importance of developing an integrative understanding of managed fen peatlands and their ecosystem functioning.
Fri, 17 January 2020
REVIEW | doi:10.20944/preprints202001.0191.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: hybrid vigor; flowering plants; apomixis; CRISPR/Cas9
Online: 17 January 2020 (10:30:45 CET)
The hybrid seeds of several important crops with supreme qualities, including yield, biotic and abiotic stress tolerance, have been cultivated from decades. Thus far, a major challenge with hybrid seed, it does not hold ability to produce plants with same qualities over subsequent generations. Apomixis exist naturally an asexual mode of reproduction in flowering plants via avoiding meiosis and ultimately leads to seed production. Apomixis possess potential to preserve hybrid vigor for multiple generations for economically important plant genotypes. The evolution and genetics of asexual seed production is unclear and need much more efforts to find its genetic architecture. To fix hybrid vigor synthetic apomixis has been suggested an alternative. The development of MiMe (Mitosis instead of Meiosis) genotypes are utilized further for clonal gametes production. However, the identification and parental origin of genes responsible for synthetic apomixis are less known and need further understanding. Genome modifications utilizing genome editing technologies (GETs) like clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (cas9) a reverse genetics tool has paved way to utilize emerging technologies in plant molecular biology. From the last decade, several genes in important crops have been successfully edited. The vast availability of GETs has made the functional genomics studies easy to conduct in crops important for food security. The disruption of expression of genes specific to egg cell MATRILINEAL (MTL) or BABY BOOM1 (BBM1) through CRISPR/Cas genome editing system can promote haploid plants. The establishment of synthetic apomixis by engineering MiMe genotype by genome editing BBM1 expression or disruption of MTL leads toward clonal seed production. In present review, we discussed the current development in plants by utilizing CRISPR/Cas9 technology and its possibility of promoting apomixis in crops to preserve hybrid vigour. In addition to this, genetics, evolution, epigenetic modifications and strategy for MiMe genotype development has been discussed in detail.
Thu, 16 January 2020
ARTICLE | doi:10.20944/preprints202001.0172.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Red bread wheat; white bread wheat; flour; rheological properties
Online: 16 January 2020 (11:47:24 CET)
In this study, rheological properties of the bread wheat flour dough from 6 wheat genotypes were determined. For the pereparation of flour, 3 red bread (Pandas, Sagitorya, Pehlivan) and 3 white bread (Kaşifbey, Göktan, Ceyhan-99) were selected as wheat genotype. To determine the rheological properties of the wheat flour dough, farinograph, extensograph, mixolab and glutograph devices were used. According to the results of the Farinograph analysis, the average development time of wheat White and red genotypes were 1.95 minutes and 8.96 minutes, respectively. According to the extensograph results of the flour samples, the most extended stability value was determined with 7.47 min in Ceyhan-99 cultivar. As a result of the research, it was determined that flour yields of red bread varieties were higher other genotypes, gas retention capacities of white bread flours were showed high result in extensograph application and resistance of dough to elongation was higher. In the Mixolab analysis, it determined that white bread wheat varieties have higher values in terms of kneading properties and gluten properties, and red bread wheat varieties have higher values in values of viscosity, amylase value and starch retrogradation.
Fri, 10 January 2020
ARTICLE | doi:10.20944/preprints202001.0098.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: bioactive components; cryogenic milling; ginseng; particle size; roasting; water solubility
Online: 10 January 2020 (10:19:54 CET)
This study was aimed at investigating the effects of roasting and cryogenic milling on particle size, water solubility, and amount of bioactive components in ginseng root. Samples were pulverized by cryogenic milling, and one treatment condition was selected for each size range (10-50 μm, and >50 μm). The selected samples were roasted at different temperatures (160-200 °C) followed by cryogenic milling. Powdered samples were analyzed for their physicochemical characteristics. Results revealed that roasted samples exhibited significantly smaller particle size than controls (not roasted, p<0.05), and the particle size of roasted samples decreased with increase in roasting temperature until flocculation occurred around 180-190 °C. With decrease in particle size of ginseng; water solubility index, antioxidant activity, total polyphenol content, and total polysaccharide content were observed to increase. Ginseng samples showed an increasing trend in antioxidant activity with decreasing particle size (p>0.05) with significantly higher values for all roasted samples compared to the controls (p<0.05). Non-polar ginsenosides such as Rg2(S), Rg2(R), Rg3(S), Rg3(R), and Rh1(S) showed an increase in temperature-dependent manner. This study revealed that roasting at certain temperature range with cryogenic milling has positive effects on ginseng by reducing its particle size, and increasing water solubility and bioactive components.
ARTICLE | doi:10.20944/preprints202001.0097.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: cryogenic milling; ginseng; particle size; physiological activity; roasting; water solubility
Online: 10 January 2020 (10:13:27 CET)
This study aimed to decrease the particle size of ginseng by roasting and cryogenic milling to increase its water solubility and physiological activity. The samples were roasted for different times (9–21 min) and generated in different sizes (10–50, and > 50 μm). All roasted samples revealed significantly smaller particle sizes than did non-roasted samples based on Sauter mean diameter (D [3,2], p < 0.05). Further, the particle sizes of roasted samples decreased till roasting up to 15 min. In terms of the water solubility index (WSI), antioxidant activity, total polyphenol content (TPC), and total polysaccharides according to particle size, 10-20 μm-sized samples showed the highest values when compared with >50 μm-sized samples. Based on roasting time, WSI values of all samples roasted for up to 15 min were higher than those of the control (not roasted) (p < 0.05). Antioxidant activity and TPC also increased with increasing roasting time. Total polysaccharide content was the highest upon roasting for 15 min except for the 10-20 μm sample. Ginsenoside content of roasted samples >20 μm size was higher than that of the control (not roasted) except after 15 min of roasting. Therefore, roasting and cryogenic milling are effective in producing ginseng root powder.
Mon, 6 January 2020
ARTICLE | doi:10.20944/preprints202001.0050.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: SAU Tomatillo-1; SAU Tomatillo-2; staking; yield; fruit length
Online: 6 January 2020 (02:41:24 CET)
An experiment was carried out at Nabogram Khamarbari, near the Manannogor, Sadar Upazila, Noakhali District, Noakhali-3814, Bangladesh during the period from 12th January 2018 to 17th April 2018, with two varieties of tomatillo (Physalis ixocarpa Brot.) SAU tomatillo-1 and SAU tomatillo-2. It was laid out in RCBD method having three replications and was conducted to observe the influence of staking and non-staking on tomatillo cultivation in coastal areas. For the study, growth indicating characters like no. of leaves plant-1, size of leaf plant-1, height of each plant, no. of branches plant-1 and yield attributing parameters such as days to first flowering, days to 50% flowering, no. of fruits branch-1, fruit weight and yield were obtained from the plants with the treatments of staking and non-staking. A wide variation was observed between two varieties of tomatillo with the effect of these treatments. According to the results highest no. of leaves branch-1, maximum size of leaves branch-1, tallest height of each plant, uppermost no. of branches plant-1, highest no. of fruits branch-1, maximum weight of each fruit and yield were obtained in the staking treatment over the non-staking treatment of SAU tomatillo-1 and in case of SAU tomatillo-2, with the same parameters the result indicated significantly upper in the staking treatment over non-staking treatment. Considering the two varieties of tomatillo, the outcome were significantly superior with staking treatment for the similar parameters. The findings of the experiment indicated that the best yield (21 tha1) and highest financial benefit could be obtained by SAU tomatillo-1 and the best tomatillo production in saline soil of coastal areas is possible by cultivating SAU tomatillo-1.
Sun, 5 January 2020
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Chinese sacbrood virus; VP1; Apis cerana; Phylogenetic analysis
Online: 5 January 2020 (15:49:12 CET)
The Chinese honeybee (Apis cerana cerana) sacbrood virus (CSBV) causes death of larvae and colony collapse, and could damage the beekeeping industry in China. We sequenced complete genomes of CSBV strains derived from the Maerkang area, Wenjiang area, and Wanyuan area of Sichuan province of China. The genome length of CSBV strains from Sichuan was 8863bp, and it contained one complete Open Reading Frame of a gene with 8544 bp that encoded a protein with 2848 amino acids. The (G+C) % and (A+T) % composition ranged from 40.6 to 40.7 and 59.3 to 59.4, respectively. A phylogenetic tree was constructed using the three CSBV strains and previously reported SBV and CSBV sequences from other regions. We found that viral strains clustered based on their region of origin and host species. The genetic sequences of the CSBV strain from Maerkang were 98.7% and 99.6% similar to CSBV strains from Wanyuan and Wenjiang, respectively. In addition, CSBV from Maerkang had 88.4%-95.2% sequence similarity to previously published genomes of CSBV or SBV from other areas. The VP1 gene sequenced in our study had a 43 bp deletion compared to VP1 sequences of CSBV from other regions in Asia. We detected 10 antigenic determinants on the VP1 protein of CSBV form Aba. Our study provides new insight into the diversity of CSBV strains in China and may help with identifying methods to prevent infection of honeybee colonies.
Tue, 31 December 2019
ARTICLE | doi:10.20944/preprints201912.0403.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Flour yield; Winter durum wheat; Grain characteristics; Structural equation model; Simulation
Online: 31 December 2019 (10:07:35 CET)
Flour yield determined the profitability of flour mill, but the intrinsic variability of the grain makes it very complex to analysis and estimate wheat grain flour yield. Simulation for flour yield attributes offer considerable advantages in flour mill, if reliable predictions of flour yield can be provided, because the wheat grain characteristics can be tested before milling. If this is possible, the characteristics thus observed could be quantified more reliably and objectively by Structural Equation Modelling (SEM). SEM was used to look for the most important wheat grain characteristics on flour yield, and then these wheat grain characteristics were used to simulate flour yield. Furthermore, the regressive equation was verified by the field experiment. The coefficient of variation of grain characteristics was low and distributed rather closely. The results of SEM showed that test weight had the most significantly effects on flour yield, followed by the hardness index. Test weight and hardness index could excellently estimate flour yield by multiplicative effect of test weight and hardness index, and which could determine 68% of the variation in flour yield. The simulation result can not only predict flour yield, but also look for the important grain characteristics for the flour yield.
Thu, 26 December 2019
Subject: Biology, Agricultural Sciences & Agronomy Keywords: wheat; UAV image; color index; texture feature index; biomass
Online: 26 December 2019 (12:27:49 CET)
In order to realize rapid and nondestructive monitoring of wheat biomass in field, field experiments based on different densities, nitrogen fertilizer and variety treatments were studied. RGB images of wheat in the main growth stage were obtained by UAV, and wheat color and texture feature indices were obtained by image processing, and wheat biomass was obtained by field sampling in the same period. Then the relationship between different color and texture feature indices and wheat biomass was analyzed to select the color and texture feature index suitable for wheat biomass estimation. The results showed that there was a high correlation between image color index and wheat biomass in different stages, and most of them reached a very significant correlation level. However, the correlation between image texture feature index and wheat biomass was poor, only a few indexes reached significant or extremely significant correlation level. Based on the above results, the color indices with the highest correlation to wheat biomass or the combining indices of color and texture feature in different growth stage were used to construct estimation model of wheat biomass. The models were validated using independently measured biomass data, and the correlation between simulated and measured values reached the significant level, RMSE were smaller. This indicated that the estimated results by the models were reliable and accurate. It also showed that the estimation models of wheat biomass combined with color and texture feature indices of UAV image were better than the single color index models. The results would provide a new method for real-time monitoring of wheat field growth and biomass estimation.
ARTICLE | doi:10.20944/preprints201912.0352.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: climate change; wheat quality; risk assessment; irrigation; CERES-Wheat; yield
Online: 26 December 2019 (10:40:01 CET)
The effects of climate change on yield and quality for different climate regions had high uncertainty. Risk assessment is an effective measure to assess the seriousness of the projected impacts for decision-makers. The modified quality model was used to simulate integrated impacts of climate change, environment and management on wheat yield and quality. Then, the Canadian Earth System Model (CanESM2) was used to forecast the daily meteorological data, and Statistical Down Scaling Model was used for downscaling. CERES-Wheat was combined with the forecasted meteorological data to simulate the future wheat yield and grain protein concentration (GPC). The risk of wheat yield and quality in three climatic regions of Shaanxi combined with two climate change scenarios of CanESM2 were assessed. Temperature increased 0.22-3.34 °C and precipitation increased 10-60 mm for RCP4.5 and RCP8.5. Elevated temperature and precipitation had positive effects on yield in all regions. The yield risk of most regions with climate change decreased 3.8%-25.1%. The GPC risk of all regions with climate change decreased 7.3%-27.2%. Irrigation decreased yield risk greatly in all regions, while had totally different effects for the three climatic regions. Yield risk with irrigation decreased 37.7%-52.1% in different climate. In contrast to previous studies, GPC risk with irrigation increased greatly 25.8%-28.9% in humid region, 3.9%-8.8% in sub-humid region, and decreased 37.7%-52.1% in semi-arid region. Climate change decreased yield risk and GPC risk together. While irrigation decreased yield risk greatly in all regions, had totally different effects for the three climatic regions.
Wed, 25 December 2019
ARTICLE | doi:10.20944/preprints201912.0335.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Bacillus cereus; mild heating; dielectric barrier discharge plasma; red pepper powder; quality
Online: 25 December 2019 (03:46:00 CET)
The synergistic efficacy of combined treatment mild heat (MH) and dielectric barrier discharge (DBD) plasma in Bacillus cereus-contaminated red pepper powder was tested. A cocktail of three strains of B. cereus (NCCP 10623, NCCP 14579, ATCC 11778) was inoculated onto red pepper powder and then treated with MH (60 ℃ for 5-20 min) and DBD plasma (5-20 min). Treatment with MH and DBD plasma alone for 5~20 min resulted in reductions of 0.23~1.43 and 0.12~0.96 log CFU/g, respectively. Combined treatment with MH and DBD plasma was the most effective at reducing B. cereus counts on red pepper powder and resulted in log-reductions of ≥ 6.0 log CFU/g. The largest synergistic values (4.24-4.42 log) against B. cereus in red pepper powder were obtained by the combination of 20 min MH and 5~15 min DBD plasma. Hunter color ‘‘L’’, ‘‘a’’, and ‘‘b’’ values of the combination-treated samples were not significantly different from those of non-treated samples. Also, no significant (p > 0.05) differences in pH values between samples were observed. Therefore, these results suggest that the combination of MH treatment and DBD plasma can be potentially utilized in the food industry to effectively inactivate B. cereus without incurring quality deterioration of red pepper powder.
Tue, 24 December 2019
REVIEW | doi:10.20944/preprints201912.0316.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Peanut; plant breeding; research; funding; genomics; INERA; cultivar; selection; Arachis hypogaea
Online: 24 December 2019 (11:07:38 CET)
Groundnut (Arachis hypogaea L.) is a major food and cash crop in Burkina Faso. Due to growing demand for raw oilseeds, there is an increasing interest in groundnut production from traditional rain-fed areas to irrigated environments. However, despite implementation of many initiatives in the past to increase groundnut productivity and production, the groundnut industry still struggles to prosper, due to several constraints including minimal development research and fluctuating markets. Yield penalty due to drought and biotic stresses continue to be a major drawback for groundnut production. This review traces progress in the groundnut breeding that started in Burkina Faso before the country’s political independence in 1960 through to present times. Up to the 1980s, groundnut improvement was led by international research institutions such as IRHO (Institute of Oils and Oleaginous Research) and ICRISAT (International Crops Research Institute for the Semi-Arid Tropics). However, international breeding initiatives were not sufficient to establish a robust domestic groundnut breeding programme. This review also provides essential information about opportunities and challenges of groundnut research in Burkina Faso, emphasising the need for institutional attention to genetic improvement of the crop.
ARTICLE | doi:10.20944/preprints201912.0315.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Lactobacillus; piglet; weaning; gut microbiota; growth enhancement.
Online: 24 December 2019 (10:59:14 CET)
The composition of bacteria in the gastrointestinal tract of piglets is easily affected by environmental changes, particularly during the weaning period. Compound strains of Lactobacillus reuteri and Lactobacillus salivarius were supplemented to piglets during pre- and post-weaning to determine their effects in improving the growth performance and ameliorating the diarrhea rate and stress caused by antioxidation in piglets. A larger number of L. reuteri and L. salivarius colonized the distal segment of the ileum and the total numbers of Lactobacillus spp. and Bifidobacterium were higher in the ileal mucous membrane and cecal lumen with probiotics supplementation. The numbers of antioxidative and immune molecules were increased in the plasma following compound bacteria (CL) supplementation, whereas cortisol and endotoxin levels were lower and growth hormone and insulin-like growth factor 1 were higher. Spearman’s and KEGG analysis of the bacterial operational taxonomic unit and antioxidative and immune indices and metabolic genes indicated that the body growth modulation by CL supplementation could be attributed to optimization of the intestinal bacterial composition. Collectively, these results suggest that supplementation with CL could reduce stress and improve the growth performance of piglets during weaning by optimizing the intestinal bacterial composition.
Fri, 20 December 2019
ARTICLE | doi:10.20944/preprints201912.0273.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Capsicum annuum; flavonoids; fluorescence monitoring; bio-waste utilization
Online: 20 December 2019 (11:05:22 CET)
The green biomass of horticultural plants contains valuable secondary metabolites (SM) which can potentially be extracted and sold. When exposed to stress, plants accumulate higher amounts of these SMs, making the extraction and commercialization even more attractive. We evaluated the potential for accumulating of the flavones cynaroside and graveobioside A in leaves of two bell pepper cultivars (Mavras and Stayer) when exposed to salt stress (100 mM NaCl), UVA/B excitation (UVA 4-5 W/m²; UVB 10-14 W/m² for 3 hours per day) or a combination of both stressors. HPLC analyses proved the enhanced accumulation of both metabolites under stress conditions. Cynaroside accumulation is effectively triggered by high-UV stress, whereas graveobioside A contents increase under salt stress. Highest contents were observed in plants exposed to combined stress. Effects of stress on overall plant performance differed significantly between treatments, with least negative impact on aboveground biomass found for high-UV stressed plants. The usage of two non-destructive instruments (Dualex and Multiplex) allowed us to gain insights in ontogenetical effects at the leaf level and temporal development of SM contents over time. Indices provided by those devices correlate fairly with amounts detected via HPLC (Cynaroside: R2 = 0.46 – 0.66; Graveobioside A: R2 = 0.51 – 0.71). The concentrations of both metabolites tend to decrease at leaf level during the ontogenetical development even under stress conditions. High-UV stress is a promising tool for enriching plant leaves with valuable SM without major effects on plant biomass. All data is available online .
Tue, 3 December 2019
ARTICLE | doi:10.20944/preprints201912.0024.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: wheat variety bn207; genome composition; fish; snp; chromosomal variations
Online: 3 December 2019 (11:49:52 CET)
Development and deployment of wheat varieties with high yields, wide adaptability, good quality, multiple-resistance to abiotic and biotic stresses, and efficient response to fertilizers have greatly contributed to global wheat sustainable production. The genomic composition of key commercial wheat variety can help understand the genetic basis underlying the development of new variety and permit increased breeding efficiency. In this study, we report the chromosomal and genomic compositions of BN207, presently the leading wheat variety in the southern region of Huang-Huai River Valley, the most important wheat producing area in China through an integrated analysis using fluorescent in situ hybridization (FISH) and wheat 15 K SNP array. Our results showed that BN207 inherited 55.3% and 40.7% of its genome from its male parent BN64 and female parent ZM16, respectively, and generating 64 novel or recombined loci. Besides, we detected nine chromosomal variations in Bn207 and its parents and ten sister lines, and physically mapped two variations, the pericentric inversion of chromosome 6B, and large tandem repeat sequence block at the long arm of 5A, both had positive effects on agronomic traits, by integration of FISH and SNP loci recombination analyses. These results will provide a reference for breeding of high yield wheat varieties as BN207, and the application of founder parents BN64 and ZM16, which are being utilized frequently in wheat breeding programs in Henan Province and surrounding areas.
Sun, 24 November 2019
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Pantoea agglomerans; plant growth-promotion; Solanum lycopersicum L.; indole-3-acetic acid; siderophores; arsenic resistance; complete genome; horizontal gene transfer
Online: 24 November 2019 (15:29:55 CET)
Distinctive strains of Pantoea are used as soil inoculants for their ability to promote plant growth. Pantoea agglomerans strain C1, previously isolated from the phyllosphere of lettuce, can produce indole-3-acetic acid (IAA), solubilize phosphate, and inhibit plant pathogens, such as Erwinia amylovora. In this paper, the complete genome sequence of strain C1 is reported. In addition, experimental evidence is provided on how the strain tolerates arseniate up to 100 mM, and on how secreted metabolites like IAA and siderophores act as biostimulants in tomato cuttings. The strain has a circular chromosome and two prophages for a total genome of 4,846,925-bp, with a GC content of 55.2%. Genes related to plant growth promotion and biocontrol activity, such as those associated with IAA and spermidine synthesis, solubilization of inorganic phosphate, acquisition of ferrous iron, and production of volatile organic compounds, siderophores and GABA, were found in the genome of strain C1. Genome analysis also provided better understanding of the mechanisms underlying strain resistance to multiple toxic heavy metals and transmission of these genes by horizontal gene transfer. Findings suggested that strain C1 exhibits high biotechnological potential as plant growth-promoting bacterium in heavy metal polluted soils.
Tue, 19 November 2019
ARTICLE | doi:10.20944/preprints201911.0226.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: communities; disease; multi-functional; perceptions; soil erosion; uprooting
Online: 19 November 2019 (10:00:52 CET)
Changes in land-use have been observed in banana-based systems in the African Great Lakes region affected by Xanthomonas wilt disease (XW) of banana. Through participatory focus group discussions (FGDs) and the 4-cell method, changes in land-use were retrospectively assessed in 13 XW-affected landscapes/villages along a 230 km transect from Masisi (XW arrived in 2001) to Bukavu (XW arrived around 2014) in eastern Democratic Republic of Congo during 2015. The four-cell chart ranked land-use by mapping the area under production and the number of households involved in production. Farmers’ perceptions on the sustainability of new land-uses were also documented. Soil nutrient content and erosion levels were measured for five major land-use options/ trajectories on 147 fields across 55 farms in three landscapes along the transect. From being ranked the most important crop (92% of landscapes i.e. produced on large areas of land and by many households) before XW outbreaks, its importance had declined with most households in 36% of the landscapes growing it on smaller farms while in 64% of cases by few households on smaller pots. Farmers uprooted entire banana mats or fields, expanding land under other crops, mainly beans, taro, sweet potato, cassava, maize, coffee and eucalyptus. Species richness did not change at landscape level, though 21 crops were introduced at farm level. Land-use for banana is however still perceived to be more sustainable due to its multi-functional roles. Soils under banana plots were found in general to be better in their chemical attributes while high erosion levels (Mg ha-1 year-1) were observed under cassava (1.7-148.9) compared with banana (0.3-10.7) and trees (0.3-5.9). The current shift away from banana could thus have profound effects on supply of key services and sustainability of the production systems. This study offers a good basis/entry point for interventions in the XW-affected landscapes.
REVIEW | doi:10.20944/preprints201911.0221.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Aloe vera; chemical constituents; antimicrobial activity; postharvest storage; biodegradable; edible coating
Online: 19 November 2019 (03:33:32 CET)
Edible coating gels developed from the Aloe vera plant have been used as a traditional medicine for about 3000 years. Aloe vera contains 110 potentially active constituents from six different classes: chromone and its glycoside derivatives; anthraquinone and its glycoside derivatives; flavonoids; phenylpropanoids and coumarins; phenylpyrone and phenol derivatives; and phytosterols and others. Apart from medicinal uses, Aloe gels have an important role in food preservation as edible coatings. They provide an edible barrier for atmospheric gases and moisture, and help to reduce the respiration and transpiration of fresh produce, which helps to preserve its postharvest quality. To date, numerous studies have been conducted on the postharvest use of Aloe vera gel. The present review article summarizes and discusses existing available information about the chemical constituents, antimicrobial activity, and food preservative characteristics of Aloe vera.
Fri, 15 November 2019
ARTICLE | doi:10.20944/preprints201911.0169.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: greenhouse gases; operating profit; mitigations; carbon price; environmental footprint
Online: 15 November 2019 (03:51:03 CET)
Between 2011 and 2016 small-scale farm trials were run across three dairy regions of New Zealand (Waikato, Canterbury, Otago) to compare the performance of typical regional farm systems with farm systems implementing a combination of mitigation options most suitable to the region. The trials ran for at least three consecutive years with detailed recording of milk production and input costs. Nitrate leaching per hectare of the milking platform (where lactating cows are kept) was estimated using either measurements (suction cups), models, or soil mineral nitrogen measurements. Post-trial, detailed farm information was used in the New Zealand greenhouse gas inventory methodology to calculate the emissions from all sources; dairy platform, dairy support land used for wintering non-lactating cows (where applicable) and replacement stock, and imported supplements. Nitrate leaching was also estimated for the support land and growing of supplements imported from off-farm using the same methods as for the platform. Operating profit (NZ$/ha/year), nitrate leaching (kg N/ha/year), and greenhouse gas emissions (t CO2-e/ha/year) were all expressed per hectare of milking platform to enable comparisons across regions. Nitrate leaching mitigations adopted in lower-input (less imported feed and N fertiliser) farm systems reduced leaching by 22 to 30 percent, and greenhouse gas emissions by between nine and 24 percent. The exception was the wintering barn system in Otago where nitrate leaching was reduced by 45 percent but greenhouse gas emissions were unchanged due to greater manure storage and handling. Important drivers of a lower environmental footprint are reducing nitrogen fertiliser and imported feed. Their effect is to reduce nitrogen surplus and feed flow through the herd and drive down both greenhouse gas emissions and nitrate leaching. Emission reductions in the lower-input systems of Waikato and Canterbury came at an average loss of profit of approximately NZ$100/t CO2-e (three to five percent of industry average profit per hectare).
Tue, 12 November 2019
ARTICLE | doi:10.20944/preprints201911.0128.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: ditches; grain yield; lodging resistance; root traits; wet-seeded rice
Online: 12 November 2019 (10:25:04 CET)
The mechanical hill wet-seeded rice machine is benefits to establish uniform seedling, and ditches were established by using this machine. However, little knowledge is known on the effect of the establishment of ditches on growth, lodging and yield, and their relationship with root traits. In this study, two field experiments were conducted during 2012 and 2013 with using two super rice varieties (i.e. hybrid rice ‘Peizataifeng’ and inbred rice ‘Yuxiangyouzhan’) grown under three ditches establishment treatments (i.e. T1: both water ditches and seed ditches were established by the machine, T2: seed ditches were established by the machine, T3: neither water nor seed ditches were established by the machine). The lodging index and lodging resistance traits, the grain yield and above-ground dry weight and the root traits were measured. The results showed that the lodging index was significantly affected by the treatments with ditches. The strongest lodging resistance was detected in mechanical hill wet-seeded rice with ditches treatment in both 2012 and 2013. The lodging resistance was strongly related to the breaking resistance, the root volume and root superficial area at the heading stage and maturity stage and the total root length at the heading stage. No significant difference was investigated in grain yield or dry weight of mechanical hill wet-seeded rice. Yuxiangyouzhan showed higher grain yield, dry weight and better lodging resistance but unfavorable root growth attributes than Peizataifeng. Therefore, the mechanical hill wet-seeded rice with ditches treatment increased rice lodging resistance is related to root traits.
Sun, 3 November 2019
ARTICLE | doi:10.20944/preprints201911.0016.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: olive tree, drought and re-watering, soil water balance, irrigation, root, neutron probe
Online: 3 November 2019 (15:28:25 CET)
This paper presents a study of a field trial experiment at olive orchard irrigated by runoff harvesting system under a dry climate which was carried out on 5-year-old olive trees (Olea europaea. L, cv. Barnea) in the middle of Negev desert, starting right after the floods, onwards during the summer growing season. The beginning of the experiment occurred after 2 years with little rain and no run-off events. The olive trees were under severe drought stress when we first initiated controlled flooding in 2017. In the second research year (2018), a massive natural flood had occurred at the end of April. Results show that the water distribution within the soil was highly inhomogeneous even under flood conditions. Soil water loss rate, due to transpiration was mainly correlated with the total amount of soil water and not atmospheric conditions. The relative root water uptake from shallow soil layers (0.3-1.5m) gradually reduced along the season, while the relative water uptake from the deeper layers (1.5-4m) became more pronounced.
Wed, 23 October 2019
DATA DESCRIPTOR | doi:10.20944/preprints201910.0263.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Paenibacillus; rhizosphere; non-rhizobial endophyte (NRE); Trifolium; clover; Bodega Bay; diazotroph; plant-growth promoting bacteria; free-living nitrogen fixer
Online: 23 October 2019 (03:52:41 CEST)
Paenibacillus sp. tmac-D7 was isolated from coastline growing Trifolium macraei (double-head clover) root nodules from Bodega Bay, California. The draft genome is 5,567,337 bp with a G+C% of 52.4%, an N50 of 114,261 bp, and 5,282 predicted protein-coding genes. Paenibacillus, while found in many other environments, is frequently isolated from root nodules, with many acting as plant pathogen antagonists. Paenibacillus sp. tmac-D7 is the first genome of a non-rhizobial endophyte isolate from wild Trifolium macraei (double-head clover).
Tue, 22 October 2019
ARTICLE | doi:10.20944/preprints201910.0254.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Prunus persica; edible coating; 1-methylcycyclopropene; Aloe spp; post-harvest quality
Online: 22 October 2019 (05:36:34 CEST)
The maintenance of high quality standards for prolonging shelf life of fruit and maintaining sensory and nutritional quality is a priority the horticultural products. The aim of this work was to test the effectiveness of a single treatment of edible coating based on Aloe arborescens and a combined treatment of 1-Methylcycyclopropene and edible coating to prolong the shelf-life of "Settembrina" white flesh peach fruit. White flesh peach fruit were harvested at the commercial ripening stage and treated with edible coating (EC) or 1-MCP +EC and stored for 28 days at 1°C. After 7, 14, 21 and 28 days fruits were removed from cold storage, transferred at 20°C and then analyzed immediately (cold out) and after 6 days (shelf life) to evaluate the combined effect of cold storage and room temperature. Weight loss, physical, chemical and sensory parameters were measured. Fruit treated with EC and 1-MCP +EC kept their marketing values better than CTR after 14 days of storage and 6 days of simulated shelf life, in terms of flesh firmness, total soluble solids and titratable acidity as well as sensory parameters. After 21 days of storage, all treatments showed a deterioration of the quality parameters. The single and combined application of Aloe-based coating (with 1-MCP) slowed down the maturation processes of the fruit, limited the weight loss and preserved its organoleptic characteristics.
DATA DESCRIPTOR | doi:10.20944/preprints201910.0250.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: diazotroph; rhizosphere; nitrogen-fixation; free-living non-symbiotic diazotrophs; Betaproteobacteria
Online: 22 October 2019 (04:18:16 CEST)
Here, we report the draft genome sequence of the type strain of Ideonella azotifigens DSMZ21438T (formally 1a22T = JCM15503T). Ideonella azotifigens DSMZ21438T a novel betaproteobacterial non-symbiotic nitrogen-fixing grass rhizosphere dwelling microbe. The 891,561 paired-end shotgun reads were quality filtered and decontaminated with the ATLAS pipeline, then assembled with Unicycler. The genome size is 6,257,981 bp, an N50 size of 7,849 bp, with a G+C content of 66.71%, and with 5,882 predicted protein-coding genes. I. azotifigens DSMZ21438T represents the first member of the genus isolated from rhizosphere soil, providing a framework for further study into non-alphaproteobacterial nitrogen fixation and synthetic biology applications.
Wed, 16 October 2019
ARTICLE | doi:10.20944/preprints201909.0028.v2
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Chenopodium formosanum; human dermal fibroblast; UV exposure; antioxidant activity; anti-aging; red djulis
Online: 16 October 2019 (09:23:03 CEST)
Red djulis (Chenopodium formosanum) is a native cereal plant in Taiwan; it contains abundant polyphenols, betalian and dietary fiber. The appearance of red djulis is bright red. Therefore, it is also called the “ruby of cereals”. The antioxidative activity of red djulis extract is well-understood. However, the antiaging function still remains unclear. This study examined the potential of red djulis extract for enhancing collagen secretion and preventing cutaneous aging using red djulis extracts. The red djulis extracts are comprised of an abundant active component that can effectively enhance the ability of collagen secretion of dermal fibroblasts, prevent the glycation of collagen and resist the damage of ultraviolet light exposure. After fibroblast treatment with red djulis extracts, TGM1, KRT1, KRT10 and SOD2 genes were up-regulated significantly by 2.3, 4.3, 4.4 and 27.3 times, respectively, compared to those of the control group. Additionally, it can increase COL1A2 gene expression by 43% and decrease MMP9 gene expression 33%. Therefore, it was demonstrated that red djulis extracts affect gene expressions related to the skin barrier, antioxidation and collagen. Moreover, we found positive effects on skin barrier integrity, endogenous antioxidant activity and skin collagen-preservation. The preparation of the red djulis extracts is environmental friendly and can promote the economic value of Chenopodium formosanum; thus, the proposed extract is suitable for applications in the development of food products, especially beverages, skin care and cosmetic products.
Sat, 12 October 2019
ARTICLE | doi:10.20944/preprints201910.0138.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: climate; rainfed wheat; N fertilization; split and full N application; photosynthetic rate; agronomic traits
Online: 12 October 2019 (05:25:52 CEST)