Biology and Life Sciences

Abstract: The demand for uniform and high-yielding vegetable varieties has accelerated the erosion of vegetable biodiversity and the marginalisation of local adapted plant genetic resources (PGR) and landraces that do not meet conventional registration standards. This review critically evaluates the European Amateur Varieties (AVs) regime as a regulatory pathway for the conservation and commercialisation of local PGR. Based on the European Common Catalogue (CC), 1,284 AVs were identified (5.5% of all vegeta-ble varieties listed in the CC), with a markedly uneven distribution across countries and maintainers. France accounted for 23.1% of European AVs, followed by Germany (20.2%) and the Netherlands (13.6%). Most AVs (79%) were registered by private maintainers, while the presence of public institutions and third-sector maintainers highlight the regime’s dual function: on the one hand, it supports the commercialisa-tion of low-yielding varieties in niche markets; on the other, it may facilitate the mar-keting and conservation of landraces. A detailed analysis of Italian AVs further clarifies this pattern: of the 85 AVs registered in Italy or by Italian maintainers abroad, 79% were commercial varieties or F1 hybrids, while 21% were local landraces. In addition, 40% of Italian AVs were registered by maintainers based abroad, mainly in Israel, Spain, and Japan. Overall, the AVs regime addresses multiple needs but has limited impact on the European seed market. Greater coordination with the Conservation Va-rieties (CVs) regime could strengthen the conservation, protection, and valorisation of landraces and local PGR.

Abstract:

This study examines the competitive interactions between common bean (Phaseolus vulgaris L.) and two problematic weed species, Amaranthus palmeri S. Watson (Palmer amaranth) and Ipomoea purpurea L. (common morningglory), using a replacement series design. The analysis evaluates important competition indices namely relative yield (RY), total relative yield (TRY), and key growth parameters, height and biomass produced by the crop and weeds, along with common bean yield components (i.e., pods per plant, seeds per pod, and pod weight) across the varying proportions of crop-to-weed ratios (100:0, 75:25, 50:50, 25:75, and 0:100). Results demonstrate that I. purpurea exerts significantly greater competitive pressure than A. palmeri, with significant suppression of common bean yield at high weed densities. Total relative yield analysis reveals overyielding at the 50:50 proportion, suggesting niche differentiation or competitive equivalence between species. Yield component analysis indicates that weed competition primarily reduces pod number per plant, with secondary effects on seed set and pod biomass. These findings have provided insights into common bean-weed competition while exerting important implications for integrated weed management strategies in bean production systems.

Abstract: Canistel (Pouteria campechiana (Kunth) Baehni) is a tropical evergreen fruit tree native to Mesoamerica and increasingly cultivated in southern China for its high-value, nutrient-dense fruits. Despite growing commercial interest, comprehensive knowledge of this species remains fragmented. This review systematically synthesizes current research on canistel, covering its botanical characteristics, germplasm resources, propagation and cultivation techniques, nutritional composition, phytochemical diversity, pharmacological bioactivities, and food processing applications. The fruit is rich in carbohydrates, carotenoids (particularly lycopene and β-carotene), phenolic compounds (including gallic acid, catechin, and myricitrin), and essential minerals, while the seeds represent an underutilized source of high-amylose starch (up to 68.1%) with superior thermal stability. Pharmacological studies have demonstrated significant antioxidant, anti-inflammatory, hepatoprotective, analgesic, and immunomodulatory activities, largely attributable to its polyphenolic and triterpenoid constituents. Recent advances in encapsulation and oil-based fortification have improved the stability and bioaccessibility of canistel carotenoids, opening new avenues for functional food development. However, critical research gaps remain, including limited germplasm characterization, insufficient molecular breeding tools, narrow product diversification, and a lack of long-term toxicological and clinical data. This review identifies these challenges and proposes future research directions to facilitate the sustainable industrial development of canistel.

Abstract: This study evaluated deficit irrigation (DI; 55% of crop evapotranspiration (ETc) from BBCH 76 to four days after harvest, followed by rewatering) compared with full irriga-tion (FI; 100% ETc) in ‘Regina’ trees. DI reduced soil water, tree water status, light-saturated photosynthesis (ASAT) and stomatal conductance (gs). However, temporal changes in ASAT were weakly related with leaf water potential (ΨL) and closely related to gs and mesophyll conductance (gm). DI modified non-structural carbon partitioning in leaves, increasing sorbitol concentration by 27% and decreasing sucrose by 57% without affecting total soluble sugars. At the same time, lignin fluorescence decreased under DI whereas leaf mass per area (LMA) and stomatal density remained unaffected. After harvest and rewatering, ΨL increased in both treatments, but leaf gas exchange activity dropped accompanied by increases in lignin fluorescence and LMA. Despite an 8% de-crease in fruit size, fruit yield was maintained, improving water productivity by 67%. Our results indicate that sweet cherry responses to DI are not solely determined by water status, but also involve carbon partitioning, leaf structural traits and source-sink dy-namics, allowing yield to be maintained at the expense of fruit size.

Abstract: Future International Space Station (ISS) mini-gardens must provide fresh produce repeatedly while maintaining water and nutrient conditions within a small, reusable root-zone volume. This study evaluated the operational performance of staggered planting and selective harvesting over four months in a ground-based Utah Reusable Root Module (URRM) simulator operated as a zero-discharge system. Five independent root modules (RMs), providing a total planted area of approximately 0.40 m², were planted with leafy greens, bonsai basil, and dwarf tomato. The system produced 4,299 g of fresh edible biomass, with produce available on 77 of the 100 days within the harvest period. Daily water use remained below approximately 2 L d⁻¹ for most of the trial, and peak demand occurred at different times among RMs. RMs containing established tomato plants behind newly planted leafy greens showed lower water-use peaks and biomass production, suggesting incomplete use of module capacity. Lettuce performed well during the first cycle but was less consistent in subsequent cycles, whereas mizuna and kale provided more consistent production under reused-media conditions. Bulk electrical conductivity (bulk EC) declined during periods of rapid crop growth, indicating that nutrient depletion, rather than salinity accumulation, was the main root-zone risk under zero-discharge operation. These results indicate that ISS mini-garden operations can distribute harvests and water demand over time, but crop calendars should coordinate planting dates, crop architecture, harvest timing, residue management, reused-media constraints, and root-zone nutrient monitoring across independently managed modules.

Abstract: Pholidota chinensis is an orchid with both medicinal and ornamental value. Due to overharvesting and limited natural reproduction, its wild populations have declined sharply. Although aseptic sowing enables large-scale propagation, climate-driven extreme heat poses a threat to seedling production. However, the physiological responses and propagation potential of P. chinensis seedlings under heat stress remain poorly understood. This study examined six-month-old seedlings under four temperatures (34℃, 36℃, 38℃, 40℃) for up to 96 h. Photosynthetic performance was assessed via UV-Vis spectroscopy and chlorophyll fluorescence (Fv/Fm), and propagation potential via stem segment regeneration. Unexpectedly, high-temperature stress induced a non-monotonic and temperature-specificpattern of pigment alteration: 34℃ reduced total chlorophyll to ~40% of initial value, whereas 36℃, 38℃, and 40℃ maintained 70%–95%, revealing that pigment content did not decline monotonically with increasing temperature. Pigment degradation became increasingly synchronized at higher temperatures, with chlorophyll b and carotenoid absorbance strongly correlated with chlorophyll a peaks (r > 0.85–0.90, P < 0.01). In contrast, Fv/Fm declined in a strictly temperature-dependent manner, from 0.74 to 0.50 (34℃), 0.45 (36℃), 0.41 (38℃), and 0.25 (40℃) at 96 h. Notably, 36℃ showed signs of partial PSII recovery, while the 36–38℃ range represented a critical transition zone, with 38℃ showing sustained suppression without clear recovery. Fv/Fm correlated strongly with proliferation coefficient (r > 0.85, P < 0.01), with proliferation severely compromised below Fv/Fm = 0.40 and completely lost at 0.25. These findings demonstrate that pigment content and photosynthetic functionality respond to heat stress through distinct mechanisms in P. chinensis seedlings. The strong Fv/Fm–regenerative capacity correlation supports chlorophyll fluorescence as a rapid, non-destructive indicator for early stress diagnosis and heat-tolerant material screening.

Abstract:

Citrus is an important fruit crop worldwide and Colletotrichum species are important pathogens of this crop. Colletotrichum species infect a wide range of citrus tissue such as leaves, twigs, flower petals, immature and mature fruit, causing substantial losses in yield, fruit quality, and marketability. This review is a critical assessment of the major Colletotrichum species associated with citrus diseases, their global diversity, distribution, and biosecurity implications. This review also identifies areas in need of further research. Thirty-nine Colletotrichum species have been reported in association with citrus globally. Most Colletotrichum species are plant pathogens, while several are saprobes or exhibit endophytic or latent lifestyles. They also vary in host range, aggressiveness, and environmental adaptation. Several species can infect citrus hosts or tissues beyond those from which they were originally isolated, while some also infect plants from other genera. The nature of infection by Colletotrichum species highlights the need to include non-wound inoculation in bioassays designed to assess the ability of Colletotrichum isolates to penetrate the cuticle and epidermis and cause infection. Accurate identification, pathogenicity testing, and rapid molecular detection are therefore important for disease management, quarantine inspection, and plant biosecurity risk assessment.

Abstract: Buddleja saligna and Euclea natalensis are widely used in traditional medicine and have ornamental and cosmeceutical value. However, propagation methods are scarce, highlighting the need for sustainable propagation techniques to support commercialization and ensure a consistent supply of high-quality material. Therefore, this study investigated the influence of temperature on seed germination and seedling emergence, as well as the effects of cutting position, growth medium, season, and the use of a plant growth regulator on the success of vegetative propagation. Seed germination of B. saligna was highest at 25 °C (96%), with optimal mean germination time (3.1 days), mean emergence time (3.9 days), germination index (145.2), shortest time to 50% germination (2.6 days), and shortest time to 50% emergence (3.98 days). However, results were not significantly different from 20 °C and 30 °C. For E. natalensis, maximum germination (98%) occurred at 20 °C, with no significant differences to 25 °C and 30 °C. For B. saligna, significant interactions between season and cutting position affected leaf and bud formation. The best rooting percentage (7%) was achieved by stem cuttings treated with Dynaroot^TM 3 (0.8% IBA) and planted in coco peat (M2). For E. natalensis, no survival or rooting was observed in any of the treatment combinations. Overall, seed propagation was more effective, but vegetative propagation is preferable for producing uniform high-quality extracts as seed propagation may introduce variation. Therefore, further research is needed to establish reliable vegetative propagation protocols for both species.

Abstract: In perennial fruit trees, erratic floral initiation and alternate bearing represent major horticultural challenges, yet how vegetative shoot maturity conditions low-temperature responsiveness remains poorly understood. Here, using litchi (Litchi chinensis Sonn.) as a model, we deciphered the physiological and molecular framework governing maturity-dependent floral induction under winter chilling. Mature terminal shoots exhibited exceptional flowering competence and superior inflorescence morphology, whereas immature expanding shoots failed to initiate pure panicles. Dynamic metabolic profiling revealed that shoot maturation established a high-energy status characterized by elevated sucrose accumulation and sustained transcription of trehalose-6-phosphate synthase genes (LcTPS1/3/4). At the transcriptional level, specific members of the LcSPL1, LcSPL3, and LcSPL10 were strongly upregulated in mature shoots, reaching peak expression at the "whitish millet" stage marking morphological flower bud differentiation. Functional characterization in Arabidopsis thaliana confirmed that ectopic expression of LcSPL1/3/10 significantly accelerated flowering time and reduced rosette leaf number. Mechanistically, dual-luciferase reporter assays demonstrated that LcSPL1, LcSPL3, and LcSPL10 directly transactivated the promoter of the florigen gene LcFT1, with LcSPL1 exerting the strongest transactivation, whereas the immature shoot-enriched LcSPL9 repressed LcFT1 expression. Concurrently, mature leaves exhibited a dramatic surge in LcFT1 transcript levels alongside persistent suppression of the floral repressor LcTFL1. Together, our findings demonstrate that shoot maturity confers floral competence through an integrated T6P metabolism and LcSPL1/3/10–LcFT1 transcriptional cascade, providing crucial theoretical insights and actionable targets for mitigating alternate bearing in perennial woody crops.

Abstract: Low temperature severely restricts the growth of Hemerocallis fulva, yet the tissue-specific molecular regulatory networks governing cold adaptation in H. fulva remain poorly understood. In this study, phenotypic observation and comparative transcriptome analyses were performed on cold-treated and control roots and leaves of H. fulva. Phenotypic data showed that cold stress significantly suppressed seedling growth, root biomass, and reproductive development of daylily. Transcriptome identification obtained 9504 DEGs in roots and 6916 DEGs in leaves, with only 3165 shared cold-responsive genes, indicating largely divergent transcriptional programs between underground and aerial organs. KEGG enrichment analysis demonstrated that hormone signal transduction, antioxidant pathways, and soluble sugar metabolism represented core modules of the cold response. Further tissue-specific expression profiling revealed distinct regulatory patterns of three key phytohormone pathways: ethylene biosynthesis and downstream ERF/DREB/COR genes were predominantly activated in roots or leaves; gibberellin pathway exhibited opposite transcriptional trends in roots and leaves, with cold triggering DELLA accumulation to restrain growth; ABA biosynthetic genes (CHY-β, ZEP, NCED, ABA2, ABA3) were universally upregulated in both tissues, while ABA signaling components displayed root-leaf divergent expression patterns. In addition, cold stress induced comprehensive transcriptional activation of enzymatic antioxidant genes (SOD, CAT, POD, GPX, GST, GSH) to eliminate excess reactive oxygen species, with stronger induction observed in roots. For osmoprotective carbohydrate metabolism, key biosynthetic genes of inulin-type fructan, raffinose family oligosaccharides (RFOs), and trehalose were significantly upregulated. In contrast, catabolic enzyme genes were repressed in both roots and leaves, jointly promoting soluble sugar accumulation to maintain osmotic homeostasis. Collectively, these findings reveal the tissue-specific transcriptional landscape of cold acclimation in H. fulva and provide a theoretical foundation for molecular breeding of cold-tolerant daylily plants.

Abstract: Peach (Prunus persica) production and the northward expansion of its cultivation boundaries are severely constrained by recurrent extreme climatic events. Based on time-series transcriptomic analysis and qRT-PCR validation, multiple candidate transcription factor genes responsive to abscisic acid (ABA) were identified (PpERF48, PpERF017, PpMYB6, PpWRKY46, PpWRKY40, and PpbHLH35). Among these, PpMYB6 was further characterized through bioinformatic analysis, and transgenic peach callus and Arabidopsis thaliana lines overexpressing PpMYB6 were generated, revealing its dual role in modulating plant growth and conferring low-temperature stress tolerance. Yeast one-hybrid and dual-luciferase reporter assays confirmed that PpMYB6 directly binds to the PpCBF2 promoter to activate its transcription, thereby enhancing cold resistance. Furthermore, yeast two-hybrid library screening identified DWARF8 as a candidate interacting protein, pointing to a putative mechanism by which PpMYB6 may negatively regulate vegetative growth via the gibberellin pathway. Together, this study elucidates a novel molecular framework governing cold tolerance and growth balance in peach, providing a promising target gene for molecular breeding of cold-resistant cultivars and rootstocks.

Abstract: Three viruses, Telosma mosaic virus (TeMV), East Asian passiflora virus (EAPV), and Cucumber mosaic virus (CMV), are widespread in Chinese passion fruit growing regions. Co-infection by these three viruses was confirmed in symptomatic field samples collected from Guilin. To evaluate the effectiveness of shoot tip culture alone for virus elimination, in vitro organogenesis was examined, and both direct (DOR) and indirect (IOR) regeneration pathways were observed. In the DOR pathway, organogenic buds and nodules were induced at a rate of 40.83%, and 14.86% of explants produced adventitious buds longer than 1 cm. In the IOR pathway, callus was induced at a rate of 26.67%, and callus-derived meristemoids yielded a bud induction rate of 7.46%. Semi-quantitative PCR analysis showed that only a few virus-free plantlets were obtained, and no regenerated plantlets were found to simultaneously eliminate two or three viruses. No significant difference in median virus elimination efficiency was detected between the DOR and IOR pathways (TeMV: 0% vs. 16.67%; EAPV: 16.67% vs. 0%; CMV: 33.33% vs. 16.67%). SSR analysis confirmed genetic stability in the DOR pathway, whereas a polymorphism rate of 27.27% was observed in the IOR pathway. These findings indicate that the DOR pathway maintains genetic stability while achieving elimination of certain viruses in a small number of co-infected plantlets, providing a basis for subsequent secondary virus elimination and combined treatments.

Abstract: Understanding the spatial relationship between crop roots and soil biological functioning is essential for improving orchard management. This study investigated the spatial distribution of pear roots and selected soil biological indicators in five intensive ‘Abbé Fétel’ pear orchards in Emilia-Romagna, Italy, representing eight orchard–rootstock combinations. Soil cores were collected from along-row and inter-row positions at two depths (0–20 and 20–40 cm). Root length density (RLD), soil organic matter (SOM), microbial biomass carbon (MBC), soil basal respiration (SBR), and the activities of alkaline phosphatase (ALP), β-glucosidase (BGLU), and N-acetyl-β-D-glucosaminidase (NAG) were determined. Linear mixed-effects models showed that RLD was significantly higher along the tree row and in the upper soil layer, indicating that pear roots were concentrated within the shallow along-row soil. Soil depth was the main factor influencing all biological indicators. SOM was higher along-row, whereas MBC varied mainly with depth. In contrast, BGLU and NAG activities were higher in the grass-covered inter-row despite lower pear-root density, while SBR showed the highest values in the shallow along-row soil. These findings demonstrate that soil biological indicators do not necessarily mirror crop-root distribution. Instead, belowground functioning in intensive pear orchards reflects the combined influence of crop roots and inter-row vegetation, highlighting the ecological importance of both orchard compartments when assessing soil functioning.

Abstract: The genus Renanthera is valued for its fiery-red floral coloration and distinctive spider-like floral architecture; however, the molecular mechanisms underlying floral organ specialization and perianth color differentiation remain poorly understood. In this study, using integrated morphological, transcriptomic, and metabolomic analyses of R. coccinea, we found that the cell types of the dorsal and lateral perianth organs were broadly similar but clearly distinct from those of the lip and the column. Developmentally, the organ-specific expression patterns of AGAMOUS-LIKE6-1/2 (AGL6-1/2), APETALA3-1/2 (AP3-1/2), and AGAMOUS (AG) were consistent with the conserved orchid floral organ identity model. Furthermore, lip-enriched expression of brassinosteroid-responsive RING H2 (BRH1) and flavin-containing monooxygenase YUCCA10 (YUC10) suggests that brassinosteroid- and auxin-associated pathways may contribute to lip specialization, especially spur development. Regarding pigmentation, high expression of flavonoid 3'-hydroxylase (F3'H) was associated with a cyanidin-dominated anthocyanin profile. The color divergence among the dorsal sepal, petals, and lateral sepals was associated with differential expression of UDP-glucose: flavonoid 3-O-glucosyltransferase (UFGT), which was co-expressed with plant U-box protein 9 (PUB9) and carbon catabolite repressor 4 (CCR4), resulting in distinct patterns of pigment modifications. These findings provide a molecular framework for understanding floral organ development and color patterning in R. coccinea and candidate genes for future validation and molecular breeding in Renanthera.

Abstract: Purslane (Portulaca oleracea L.) is an annual plant widely distributed throughout the world and has long been used as both food and medicinal plant. In recent years, it has attracted attention as potential functional food and sustainable plant resources. Its tolerance to drought, high temperature, and salt stress has also increased interest in its use as an alternative leafy vegetable under climate change. This review summarizes the compositional diversity of purslane, starting from comparisons between wild and cultivated types. Based on previous reports, the components found in wild and cultivated purslane are compared, and factors that may explain their differences are dis-cussed. Also, their traditional food uses, safety, and current evidence from human studies are introduced. Available evidence suggests that some differences can be observed between wild and cultivated purslane, but these differences are not always consistent. They may also be affected by plant part, growth stage, harvest time, fertilization, growing environment, and processing methods. Overall, comparative studies that consider genetic background, cultivation conditions, plant part, harvest stage, and processing conditions together are important for using purslane as a food and for evaluating its functional properties and safety.

Abstract: This study evaluated the effect of an integrated irrigation practice (IP), including reg-ulated deficit irrigation (RDI), managed through an IoT-based platform, on a pear or-chard (Pyrus communis L., cv. ‘Krystali’) compared to the farmer’s standard practice (FP). Tree response was evaluated through the measurement of tree water relations, leaf physiological functions, biochemical parameters, fruit growth and quality, pro-duction, and aerial multispectral NDVI imaging. IP achieved 15.8% water savings, sig-nificantly enhancing water-use efficiency and increasing yield per tree. However, IP trees exhibited higher crop water stress index - CWSI values and lower midday stem water potential -Ψstem than FP, particularly by late July, indicating progressive water stress. Leaf-level responses revealed morphological and biochemical alterations to drought, including increased leaf mass per area (LMA), dry matter content (DM), and accumulation of proline, alongside declines in chlorophyll pigments. Despite these stress indicators, gas exchange parameters were maintained in IP, possibly due to fruit load modulating source–sink relationships and surpassing stomatal limitations. IP re-duced vegetative growth, as evidenced by lower winter pruning material mass, but this did not result in improved fruit quality. IP produced smaller fruit with lower an-tioxidant activity, polyphenolic content and soluble solids content/acidity ratio, alt-hough fruit firmness was improved. NDVI did not detect differences between the treatments on vegetative growth, or on canopy greenness, suggesting that IP trees maintained adequate photosynthetic capacity or that water stress was moderate for NDVI detection. The study highlights the need for integrating irrigation management with fruit thinning and careful scheduling to optimize both water productivity and marketable fruit quality in water-scarce pear production systems.

Abstract: Stem blight, caused by Phomopsis asparagi, is the most serious disease of asparagus (Asparagus officinalis L.) cultivation in warm regions of east and southeast Asia including Japan. Although Asparagus kiusianus, a wild species endemic to Japan, shows strong resistance and is cross-compatible with cultivated asparagus, the genetic basis of this resistance remains unclear. In this study, we used BC₁ populations from interspecific crosses between A. officinalis and A. kiusianus to dissect the inheritance of stem blight resistance and identify markers suitable for marker-assisted selection. Disease severity was evaluated by P. asparagi inoculation, and RAD sequencing was used to construct a linkage map and perform QTL analysis. Segregation patterns suggested that resistance was controlled by major genes and polygenic factors depending on the cross combination. A major QTL was detected on chromosome 1, and SNP_PRK showed significant association (LOD > 3). A dCAPS marker derived from SNP_PRK identified resistant individuals, with about 80% of heterozygotes showing resistance. CAPS marker PR1 discriminated susceptible, resistant, and heterozygous genotypes, and its genotyping results for all three genotypes were identical to those obtained with PRK. This marker may therefore provide a useful basis for selecting resistant lines in breeding programs.

Abstract: Sweet cherry (Prunus avium L.) is a high-value horticultural crop; however, winter freezing injury significantly limits its introduction and stable production in cold-temperate regions. In this study, annual shoots of 16 major sweet cherry cultivars were collected during the dormancy phase and subjected to a simulated low-temperature gradient. Eight physiological indicators, namely, relative electrolyte conductivity (REC), malondialdehyde (MDA) content, osmoregulatory substances, and antioxidant enzyme activities, were systematically measured along with the poststress recovery growth rate (RR). The semilethal temperature (LT₅₀) was calculated using a logistic equation, and a multidimensional comprehensive evaluation system for cold tolerance was constructed using the membership function method, principal component analysis (PCA), and cluster analysis. The results indicated that low-temperature stress significantly induced membrane lipid peroxidation and osmotic compensation in the shoots. PCA revealed four principal components—osmoregulation potential, cell membrane damage threshold, cold-protective protein synthesis, and membrane stability—with a cumulative variance contribution rate of 79.47%. Correlation analysis revealed no significant correlation between LT₅₀ (reflecting thermodynamic survival capacity) and the recovery growth rate (reflecting poststress regenerative capacity), suggesting that “passive endurance” and “active recovery” in sweet cherries are two relatively independent physiological processes. The comprehensive evaluation model classified the 16 cultivars into four cold-tolerance tiers: High Tolerance (Russia 8, Reid, Pacific Red, and Brooks); Moderate-High Tolerance (Tieton, Jiahong, Sandra Rose, and Early Lory); Moderate-Low Tolerance (Luyu, Rocket, Tamara, Lapins, Frisco, and Taisho-nishiki); and Sensitive (Summit and Kordia). The four-dimensional evaluation model developed in this study provides a scientific basis for cultivar selection in cold regions and offers a theoretical reference for the trade-off of traits in future molecular breeding for cold resistance in cherries.

Abstract: Greenhouse microclimates exhibit substantial spatial heterogeneity, whereas conventional evaluations based on average measurements cannot adequately describe the environmental conditions experienced by crops. This study developed a spatial frequency analysis method to quantify long-term temperature and relative humidity heterogeneity and coupled it with cucumber yield and downy mildew models to evaluate the biological consequences of environmental variability. Four representative greenhouse types were monitored using distributed sensor networks under different weather conditions. The proposed method successfully identified persistent environmental hotspots. Greenhouse structure determined the spatial distribution of environmental heterogeneity, whereas solar radiation primarily controlled its intensity. Long-season monitoring data indicate that the maximum spatial variations in temperature and humidity within the brick-wall solar greenhouse, the assembled greenhouse, the glass greenhouse, and the plastic multi-span greenhouse reach up to 10℃ and 46%, 8.5℃ and 46%, 12℃ and 50%, and 7℃ and 32%, respectively. The assembled solar greenhouse and plastic greenhouse exhibited higher environmental uniformity, while the brick-wall solar greenhouse and glass multi-span greenhouse showed pronounced spatial gradients. Environmental heterogeneity resulted in significant within-greenhouse differences in simulated cucumber yield, with the smallest variation occurring in the assembled solar greenhouse (5.3%) and the largest in the glass multi-span greenhouse (39.2%). Disease simulations further revealed clear spatial aggregation of cucumber downy mildew risk, with the southern region of the solar greenhouse exhibiting 17-67% higher cumulative infection risk than other positions. This study establishes an integrated framework linking greenhouse environmental heterogeneity with crop productivity and disease risk, providing a practical basis for spatially differentiated precision greenhouse management and greenhouse structural optimization.

Abstract: Agricultural and horticultural by-products represent an underexploited source of valuable bioactive compounds that can contribute to the development of more sustainable production systems. This study investigated the chemical composition and biological activities of the essential oil obtained from the horticultural byproducts of Artemisia dracunculus. The waste aerial biomass was subjected to steam distillation, and the essential oil was characterized by gas chromatography-mass spectrometry. Its antioxidant, α-amylase and α-glucosidase inhibitory, phytotoxic, antibacterial, and antibiofilm activities were subsequently evaluated. The essential oil was characterized as an estragole-rich chemotype (71.88%), with trans-β-ocimene and cis-β-ocimene as other main constituents. The essential oil showed moderate antioxidant activity and good enzyme inhibitory activity and, despite showing limited effects on seed germination, it significantly inhibited radical elongation in selected plant species. Furthermore, it demonstrated excellent antibiofilm activity, significantly reducing the metabolic activity of mature cells of bacteria associated with biofilm formation: Listeria monocytogenes, Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus. The results demonstrate how horticultural by-products from A. dracunculus maintain a chemical profile comparable to conventional plant material and represent a valuable source of bioactive compounds with promising potential for sustainable agri-food applications.