Background: Lipoxygenases (LOXs) catalyze polyunsaturated fatty acid oxygenation and regulate plant stress responses and oxylipin biosynthesis. This study provides comprehensive genome-wide characterization of the soybean LOX gene family, revealing unprecedented expansion and functional diversification. Methods: We identified unique GmLOX gene loci through systematic database searches and domain analysis, selecting representative isoforms to avoid transcript redundancy. Phylogenetic analysis compared 43 GmLOX with 6 AtLOX proteins. Protein structures, conserved domains, promoter cis-regulatory elements (2,000 bp upstream), and synteny relationships were characterized. Expression profiling under four abiotic stresses (alkaline, drought, heat, salt) across six time points (0–24 h) was performed using qRT-PCR. Results: Genes distribute unevenly across 10 chromosomes, with highest densities on Gm10 (11 genes), Gm08 (9 genes), and Gm07 (8 genes). Phylogenetic analysis revealed six evolutionary clades with soybean-specific expansion. Structural analysis showed 92% encode full-length proteins (average 887 amino acids) with conserved PLAT/LH2 (97%) and catalytic domains. Promoter analysis identified 23 regulatory element categories, including hormone-responsive (auxin 97%, gibberellin 89%, ABA 94%), stress-responsive (95%), and light-responsive elements (100%). Synteny analysis demonstrated ancient whole-genome duplications and recent tandem duplications drove expansion. Expression profiling revealed five functional categories: alkaline-specific, drought-dominant, heat-specific, salt-responsive, and multi-stress responsive genes. GmLOX16 showed exceptional multi-stress responsiveness (40-fold salt, 38-fold alkaline), GmLOX13 displayed strongest heat response (20-fold), and GmLOX17 exhibited peak drought sensitivity (7-fold). Conclusion: Soybean possesses the largest crop LOX family with remarkable functional diversification maintained under strong selective pressure (92% functional retention). Key stress-responsive genes, particularly GmLOX16 and GmLOX13 , represent valuable targets for molecular breeding to enhance climate resilience, providing critical genetic resources for sustainable crop improvement.

Cucumber (Cucumis sativus L.) is an economically important vegetable crop worldwide, but its yield and quality improvement are often constrained by drought stress. To investigate the physiological and molecular mechanisms by which exogenous allantoin enhances drought tolerance in cucumber, cucumber seedlings were sprayed with 6 mM allantoin solution once (A1), three times (A3), or five times (A5), while control plants were sprayed with distilled water (CK1, CK3, CK5). Each treatment consisted of three biological replicates. After treatment, drought stress was simulated by irrigating with 20% polyethylene glycol 6000 (PEG-6000) solution. The results showed that the protective effect of exogenous allantoin against drought stress was cumulative. After five applications (A5), the net photosynthetic rate (Pn) and water-use efficiency (WUE) of the plants were significantly higher than those of the corresponding control (CK5) (p < 0.01). The detached leaf water loss rate progressively decreased with an increasing number of allantoin applications, while the total leaf wax content increased approximately 2-fold (p < 0.01). Measurements of wax content in different plant tissues indicated that allantoin mainly induced wax accumulation in aboveground organs (leaf, stem, and fruit epidermis), and this effect was validated in three commercial varieties. Integrated transcriptomic and metabolomic analyses revealed that the cucumber CsCER1 gene (encoding a very-long-chain aldehyde decarbonylase) is a core allantoin-responsive gene. After silencing CsCER1 using virus-induced gene silencing (VIGS), the allantoin-induced wax accumulation and drought tolerance were almost completely lost: the wilting severity and detached leaf water loss rate of the silenced plants were comparable to those of the empty vector control, and no significant increase in wax content was observed. This study reveals a novel mechanism by which exogenous allantoin enhances drought tolerance in cucumber through activating CsCER1-mediated cuticular wax synthesis, providing a theoretical basis for the chemical regulation of drought tolerance in cucurbit crops.

Pod color is an essential economic trait of snap bean (Phaseolus vulgaris L.), and golden-yellow pods are more commercially popular than light-yellow varieties. Exploring the molecular regulatory mechanism underlying deep-yellow pod formation is essential for snap bean quality improvement. In this study, the wild-type cultivar Jinguan and the EMS-derived deep-yellow pod mutant pcm were used as materials. Integrative analyses of photosynthetic pigment quantification, genetic analysis, transcriptome sequencing, and targeted carotenoid metabolomics were performed to identify key genes and metabolic pathways governing pod color variation. Genetic analysis revealed that the deep-yellow pod trait of the pcm is stably inherited and controlled by a nuclear recessive gene. Transcriptome screening identified three differentially expressed key genes, PSY (Phvul.006G024100g), CCD4 (Phvul.002G120600g), and CYP707A (Phvul.002G122200g), whose expression patterns were strongly correlated with carotenoid accumulation. Metabolomic results demonstrated that the pcm presented reduced upstream β-carotene content, while the synthesis and accumulation of downstream chromogenic carotenoids, including zeaxanthin and capsorubin, were significantly enhanced, resulting in elevated total carotenoid content. Collectively, the differential expression of these genes remodels carotenoid metabolism and ultimately contributes to the deep-yellow pod phenotype. This study explores the regulatory mechanism of carotenoid metabolism in pod color formation, providing valuable theoretical support and genetic resources for quality breeding of snap beans.

Sugar beet production demands sustainable intensification approaches to enhance both yield and quality. This study examined the effects of foliar nano-ammonium nitrate (NH ₄ NO ₃ ) applications on five sugar beet cultivars – JAMPOL, BTS 9830, DEL 1135, ASEEL and Raspoly – over two growing seasons in Egypt’s Nile Delta, using a split-plot randomized complete block design. Three nano-NH ₄ NO ₃ concentrations (0, 50 and 100 ppm) were sprayed twice each season to assess impacts on growth, yield and quality parameters. The results indicated limited influence of treatments on primary yield metrics; taproot yields remained unaffected across all cultivars and seasons. Nonetheless, the 50 ppm treatment preserved optimal sugar quality, with sucrose content reaching 19.4 %, compared to 18 % in the controls. Carotenoid levels increased by 12 % under the 100 ppm treatment, reflecting enhanced nutritional quality. Among cultivars, ASEEL yielded the best results with taproot outputs of 34 t/ha and sugar yields of 6.1 t/ha under optimal conditions, demonstrating significant cultivar-dependent variation. Multivariate analysis revealed distinct response patterns among cultivars and treatments, with three-way interactions (Season × Cultivar × Nanoparticle) affecting several traits. Clustering identified four trait groups and three treatment clusters, highlighting sugar beet’s complex response to nanoparticles. Economic analysis shows limited benefits, with no significant increase in taproot yield, despite a rise in secondary metabolites. While nano-NH ₄ NO ₃ can modify biochemical parameters, the lack of yield improvements casts doubt on its economic feasibility. Cultivar choice primarily influences sugar beet performance, with environmental conditions also affecting treatment efficacy.

The yellow-to-green mutation in plant leaf color can be easily identified and used as a marker trait for seed purity identification, improved variety breeding, hybrid purity identification, and hybrid production. In this study, the leaves of yellow-to-green mutant ytg-1 of snap bean were selected as the experimental material, and the physiological mechanism underlying the leaf color change was studied. The mechanism was observed to belong to the lack of recovery type in the total chlorophyll stage. The decrease in chlorophyll content was due to the inhibition of the synthesis of Proto IX to Mg Proto IX. Genetic analysis revealed that a single recessive gene, pvytg-1, controlled the mutation trait. The gene was located in the 80-kb region of chromosome 10. Overall, six genes were observed within this interval, and based on gene functional annotation, Phvul.010G041700 was identified as the candidate gene. Sequencing and identification of Phvul.010G041700 revealed a single base insertion in ytg-1 compared with the wild-type, resulting in premature termination of the gene. The results of this study will facilitate the breeding and genetic improvement of snap bean in the future.

Background and aims: Snap bean is a widely planted legume vegetable crop in the world, with tender pods as its edible organ. In the actual production process, excessive fiber content in bean pods can lead to a deterioration in their taste after cooking, seriously affecting their edible quality. In order to better study the mechanism of fiber formation in bean pod walls, we selected a bean pod fiber mutant (bfm) from the bean mutant library. Methods: Fiber content determination, cytological observation, and transcriptome and metabolome analysis were performed on the pod walls of mutant bfm and its wild-type at different developmental stages. Key results: The results showed that the crude fiber content of the bfm pod wall tissue was significantly higher than that of the wild type during the mature commercial pod stage, and cellulose may be the main factor causing the increase in fiber content in the bean pod wall. During the mature commercial pod stage, the number of cells in the pod wall tissue of bfm increased significantly compared to the wild type, with an increase in phloem fibers and thicker cell walls. It is speculated that this situation led to changes in fiber content in the mutant bfm. The combined analysis of transcriptome and metabolome showed that differentially expressed genes and metabolites were enriched in metabolic pathways and secondary metabolite biosynthesis pathways. Several metabolites, including glycine, L-glutamine, D-arabinitol, and D-ribose, were associated with the expression of Phvul.007G077800 (CTL) and Phvul.003G089600 (KOR). Conclusions: These genes and metabolites may participate in coordinated metabolic pathways that influence the availability of substrates and energy required for cellulose biosynthesis, thereby potentially contributing to cellulose accumulation in the pod wall. This study provides theoretical research on the mechanism of fiber synthesis in bean pod walls, and also to provide some reference for bean breeding improvement and application practice.