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n-Propyl gallate (PG) is a phenolic compound that influences enzymatic processes, mostly involving AOX, PTOX, LOX, POD, and PPO. Here, analyses of different PG concentrations (1, 2.5, and 5 mM) during cowpea seed germination at 16, 32, and 48h showed that 2.5 mM PG partially inhibited seed germination at 16 and/or 32h, but by 48h the germination re-established. Thus, this PG concentration was chosen to study the molecular and biochemical mechanisms linked to the PG inhibitory effects and germination recovery. PG inhibition was related to lower H 2 O 2 , higher antioxidant activity, and downregulation of genes linked to cell cycle progression, energy status, and the Krebs cycle at 16 and/or 32h, but these changes were reversed at 48h. In general, genes associated with detoxification, germination-related phytohormones, and NAD(P)H metabolism were highly up-regulated across the time points. AOX1 and Pgb1 were continuously up-regulated along the time points, and linked to NR transcript level increase only at 48h. These findings indicated that AOX and the phytoglobin cycle, both systems involved in NO levels regulation, worked efficiently in germination re-establishment. However, genes other than AOX associated with potential target enzymes of PG, such as LOX, POD, PTOX and PPO (except at 48h), were mostly unchanged or down-regulated. Genes linked to glycolysis (PFK and PK) and acetate synthesis (PDC and ALDH) connected with AOX via NAD(P)+ were up-regulated under PG mainly at 48h. The data are discussed in light of AOX's role in cell reprogramming to reverse PG-induced inhibition of germination in cowpea seeds., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 Elsevier GmbH. All rights reserved.)

Long-term cadmium (Cd) exposure inhibits plant growth and development, reduces crop yield and quality, and threatens food security. Exploring the Cd tolerance mechanisms and safe production of crops in Cd-contaminated environment has become a worldwide concern. In this study, mung bean (Vigna radiata L.) cultivar Sulu (SL) and its three mutant lines (20#, 09#, and 06#) were used to compare the difference in Cd absorption, accumulation, and tolerance through pot and field experiments. 20#, 09#, and 06# are Cd-tolerant germplasms of mung bean but exist in different Cd tolerance mechanisms, 20# exhibited the lowest Cd absorption capacity, 09# possessed lower Cd translocation capacity, while 06# accumulated more Cd in protoplasts. Mung bean germplasms with higher Cd tolerance generally showed lower absorption capacity and intracellular accumulation of Cd. Besides, Cd accumulation in mung bean seeds is mainly depended on the absorption and translocation of Cd in roots and the Cd concentration in leaves, exogenous Mn supply inhibited the Cd 2+ net influx of roots and Cd accumulation in seeds, this trend was more pronounced in mung bean germplasms with higher Cd accumulation and absorption. Moreover, we characterized a Cd transporter gene VrNramp5, which was differentially expressed in different mung bean lines, overexpression of VrNramp5 increased Cd accumulation and was accompanied by Cd-sensitive phenotype in transgenic mung bean seedlings, and the Cd concentration of mung bean was significantly positively correlated with the expression levels of VrNramp5. Taken together, our findings demonstrated that different Cd tolerance mechanisms exist in mung bean. 20# is the new Cd-tolerant germplasm with low Cd absorption capacity and Cd accumulation in seeds, and has great potential for the safe production of mung bean in Cd-contaminated soils and the breeding of low Cd accumulation crop cultivars., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Masson SAS. All rights reserved.)

Vigna radiata (L.) R. Wilczek var. radiata (mungbean) is a pulse crop important for both the global protein security and sustainable crop production. Here, to facilitate genomics-assisted breeding programs in mungbean, we present a high-quality reference genome originating from the crop's centre of origin, India. In this study, we present a significantly continuous genome assembly of V. radiata Indian cultivar, achieved through a combination of long-read PacBio HiFi sequencing and Hi-C sequencing. The total assembled genome size is ~596 Mb equating to ~98% of the predicted genome size complemented by a contig N50 value of 10.35 Mb and a BUSCO score of 98.5%. Around 502 Mb of the assembled genome is anchored on 11 pseudochromosomes conforming to the chromosome count in the crop with distinctly identified telomeres and centromeres. We predicted a total of 43,147 gene models of which 39,144 protein coding genes were functionally annotated. The present assembly was able to resolve several gaps in the genome and provides a high-quality genomic resource for accelerating mungbean breeding programs., Competing Interests: Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)

Background: Munkoyo, a non-alcoholic fermented beverage, is traditionally prepared in Zambia and neighbouring countries using cooked grains and the uncooked roots of wild plant species, collectively called 'Munkoyo' plants. The drink, valued for its refreshing taste and nutritional contribution, is made using roots of several wild plant species resulting in variations in the taste and quality of the beverage. However, comprehensive information on the specific plant species used in different regions of Zambia, as well as their occurrence in terms of habitat and soil type, is missing. This gap limits our understanding of the factors contributing to Munkoyo's heterogeneity. The present study sought to identify the Zambian plant species used as an inoculum in Munkoyo fermentation and to characterize the soil in which they occur., Results: Plant and soil samples were collected from four districts in Zambia known for Munkoyo production. Using morphological taxonomy, three Fabaceae species were identified as commonly used Munkoyo plants: Rhynchosia insignis (O.Hoffm.) R.E.Fr., Rhynchosia heterophylla Hauman, and Eminia holubii (Hemsl.) Taub. Root colour differed among these species, with the Rhynchosia species having yellowish roots and E. holubii having whitish roots. To validate their identification, we evaluated three DNA barcoding markers (matK, rbcL, and ITS2) for species discrimination. All markers showed 100% PCR amplification and sequencing success rates, with ITS2 displaying the highest genetic variability and species-level resolution. Phylogenetic analyses further confirmed ITS2 as the most effective marker. Validation using samples from a fifth district reaffirmed ITS2's suitability for species-level discrimination. Soil analysis revealed significant associations between soil texture and plant occurrence: R. insignis and E. holubii were prevalent in sandy soils, while R. heterophylla was more prevalent in soils with lower sand content., Conclusions: This study identified three common Munkoyo plant species and demonstrated ITS2 as a robust DNA barcode for their identification. It also established the influence of soil texture on the distribution of these plants, contributing to the understanding of Munkoyo production's biological and environmental determinants., Competing Interests: Declarations. Ethics approval and consent to participate: Ethical clearance for this work was granted by the Tropical Diseases Research Centre (TDRC) ethics committee (Ethics number, TDREC/050/03/23), Ndola, Zambia. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)

Cowpea is deemed as a food security crop due to its ability to produce significant yields under conditions where other staples fail. Its resilience in harsh environments; such as drought, heat and marginal soils; along with its nitrogen-fixing capabilities and suitability as livestock feed make cowpea a preferred choice in many farming systems across sub-Saharan Africa (SSA). Despite its importance, Cowpea yields in farmers' fields remain suboptimal, primarily due to biotic and abiotic factors and the use of either unimproved varieties or improved varieties that are not well-suited to local conditions. Multi environment testing of genotypes is essential for recommending varieties suited for either specific or for wide cultivation. This study aimed, to identify and recommend cowpea breeding lines for wide or specific cultivation in the Sudan Savanna and Deciduous Forest zones of Ghana. The research utilized twenty early-maturing advance cowpea breeding lines and three check varieties (released varieties). The experiment was conducted in two locations: Bunso in the Deciduous Forest zone and Manga in the Sudan Savanna zone over 2020/2021 and 2021/2022 cropping seasons. Combined analysis of variance revealed a significant genotype-environment interaction (GEI) which accounted for 35.12% of the variation in yield. The environments were classified into three mega environments, with Bunso_2021 identified as the near-ideal environment where the genotypes exhibited their maximum genetic potentials. In terms of adaption, genotype UG_04 demonstrated broad adaption, showing high yield and stability across all test environments. Genotypes UG_01 and UG_02 performed particularly well in Bunso_2021 and Bunso_2022, while UG_04 and UG_14 excelled in Manga_2021. These findings provide valuable insights for selecting cowpea varieties that can enhance productivity and stability in diverse agro-ecological zones., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2025 Kusi et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Several mungbean (Vigna radiata (L.) Wilczek) cultivars are susceptible to Cercospora leaf spot (CLS) caused by Cercospora canescens Ellis & Martin, and it is necessary to explore resistance sources and understand resistance mechanisms. However, the CLS resistance mechanisms have not yet been explored. The response to CLS revealed significantly different disease severity scores in both mungbean genotypes. Hypersensitive response (HR) started to appear at 2 days after inoculation (DAI) in SUPER5 but was never observed in CN84-1. SUPER5 exhibited fewer and smaller lesions than CN84-1 during CLS infection, resulting in SUPER5 being resistant while CN84-1 was susceptible to CLS. In this study, RNA sequencing (RNA-seq) analysis was used to unravel the mechanisms of resistance to CLS in a resistant line (SUPER5) and a susceptible variety (CN84-1) upon CLS infection. A total of 9510 DEGs including 4615 up-regulated and 4895 down-regulated genes were revealed. Of these 3242 and 1027 genes were uniquely up-regulated only in the SUPER5 and CN84-1, respectively, while 2902 and 734 genes were down-regulated only in SUPER5 and CN84-1, respectively. The 843 DEGs were enriched in biological processes mainly associated with plant defense responses, defense response to fungus, protein phosphorylation and response to chitin in Gene Ontology (GO) terms analysis. KEGG pathway analysis showed that these genes were represented in plant-pathogen interaction, the MAPK signaling pathway, plant hormone signal transduction, and cell wall component biosynthesis in response to the CLS infection specifically in SUPER5. In addition, the qRT-PCR was used to analyze the expression pattern of 22 candidate DEGs belonging to pathogenesis related (PR) proteins, resistance (R) proteins, transcription factors, hypersensitive response (HR), and the essential genes involved in cell wall activity during CLS-infected V. radiata. It was found that the expression of these genes was consistent with the RNA-seq analysis, showing a highly significant correlation with a coefficient of 0.7163 (p < 0.01). The co-expression network illustrated the interactions among these genes, which were involved in multiple functions related to the defense response. Interestingly, the ones encoding PR-2, thaumatin, peroxidase, defensin, RPM1, pectinesterase, chalcone synthase, auxin efflux carrier, and transcription factors (Pti1, Pti5, Pti6 and WRKY40) were highly significantly up-regulated in SUPER5 but not in CN84-1 upon CLS infection, suggesting that they might be involved in the CLS resistance mechanisms. Moreover, SUPER5 was found to have higher β-1,3-glucanase and chitinase activity levels than CN84-1. Our findings contribute to an understanding of the CLS resistance mechanisms and may advocate the development of more effective disease management approaches., Competing Interests: Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)

Background/objectives: Cowpea is an important legume crop in sub-Saharan Africa (SSA) and beyond. However, access to phosphorus (P), a critical element for plant growth and development, is a significant constraint in SSA. Thus, it is essential to have high P-use efficiency varieties to achieve increased yields in environments where little-to- no phosphate fertilizers are applied., Methods: In this study, crop phenology, yield, and grain P efficiency traits were assessed in two recombinant inbred line (RIL) populations across ten environments under high- and low-P soil conditions to identify traits' response to different soil P levels and associated quantitative trait loci (QTLs). Single-environment (SEA) and multi-environment (MEA) QTL analyses were conducted for days to flowering (DTF), days to maturity (DTM), biomass yield (BYLD), grain yield (GYLD), grain P-use efficiency (gPUE) and grain P-uptake efficiency (gPUpE)., Results: Phenotypic data indicated significant variation among the RILs, and inadequate soil P had a negative impact on flowering, maturity, and yield traits. A total of 40 QTLs were identified by SEA, with most explaining greater than 10% of the phenotypic variance, indicating that many major-effect QTLs contributed to the genetic component of these traits. Similarly, MEA identified 23 QTLs associated with DTF, DTM, GYLD, and gPUpE under high- and low-P environments. Thirty percent (12/40) of the QTLs identified by SEA were also found by MEA, and some of those were identified in more than one P environment, highlighting their potential in breeding programs targeting PUE. QTLs on chromosomes Vu03 and Vu08 exhibited consistent effects under both high- and low-P conditions. In addition, candidate genes underlying the QTL regions were identified., Conclusions: This study lays the foundation for molecular breeding for PUE and contributes to understanding the genetic basis of cowpea response in different soil P conditions. Some of the identified genomic loci, many being novel QTLs, could be deployed in marker-aided selection and fine mapping of candidate genes.

In recent years, more agricultural lands are been converted to photovoltaic (PV) power plants for better return on investment. However, prioritizing energy generation over food production poses a significant threat to the well-being of the rapidly growing global population. Agro-photovoltaics (APV) provide an opportunity to integrate crop production under PV panels. The objective of this study was to investigate the effect of APV system on microclimate, photosynthesis, and agronomic performance of mungbean in a tropical environment. Five mungbean genotypes, Tvr18, Tvr28, Tvr65, Tvr79 and Tvr83 were assessed under three APV micro environments, East-west facing PV (WPV), West-east facing PV (EPV), and no PV (NPV) in a split plot design with 5 replications. Results obtained showed significant reduction (p < 0.05) in photosynthetic active radiation (5-47%), leaf temperature (3-9%), and in the proportion of potentially harmful unregulated energy reaching the reaction centers (19-23%) under the PV (% reduction in WPV > EPV). Relative humidity, photochemical energy conversion, plant height, number of leaves, pods, and seeds were increased significantly (p < 0.05) underneath the EPV compared to NPV. Seed weight also increased non-significantly under EPV while flowering and podding behaviour, leaf area and stem diameter were comparable (p > 0.05) in NPV and EPV. We report for the first time that microclimate, growth, photochemistry and yield performances of mungbean were improved under APV system in a tropical environment. The improved performances of mungbean under EPV compared to WPV suggest that PV orientation is important and should not be overlooked in APV system designs., Competing Interests: Declarations. Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)

This study aims to enhance sustainable disease management in black gram by identifying varieties resistant to Mungbean Yellow Mosaic India Virus (MYMIV). We screened sixteen black gram genotypes, assessing physiological, biochemical and enzymatic basis. Results revealed a range of resistance levels, with PANT URD-19 showing the highest resistance (PDI 0.47%) and Pejua the lowest (PDI 37.24%). Seven genotypes demonstrated strong resistance, highlighting the necessity for targeted breeding. Variations in leaf thickness, trichome density, stomatal frequency, and epicuticular wax content were significant, with resistant varieties like LBG-888 and PANT URD-19 exhibiting thicker leaves, higher trichome density, and more wax, correlating with reduced susceptibility. Chlorophyll content was higher in resistant varieties, while susceptible ones had reduced levels and increased sugar content, which may exacerbate MYMIV impact by attracting more whiteflies. Enzymatic analysis showed that resistant genotypes had elevated POD, SOD, and PAL activities, supporting their enhanced defense mechanisms. Multivariate analysis confirmed these findings, with leaf thickness, trichome density, and wax content negatively correlating with disease severity, while stomatal frequency and total sugar content were positively correlated. These results emphasize the potential of these traits in developing MYMIV-resistant black gram varieties and support the advancement of eco-friendly agricultural practices., Competing Interests: Declarations. Competing interests: The authors declare no competing interests. Ethical approval: Not applicable, as no approval of research ethics committees was required to accomplish the goals of this study because experimental work was conducted with an unregulated plant varieties., (© 2024. The Author(s).)

The increasing frequency of heat stress events due to climate change disrupts all stages of plant growth, significantly reducing yields, especially in crops like mung bean (Vigna radiata (L.) R. Wilczek). Mung beans are vital grain legumes in Southeast Asian countries and are crucial for food security. Thus, it is essential to understand the physiological and yield-related trait responses of mung bean genotypes and harness germplasm with enhanced heat tolerance to mitigate the impact of rising heat stress on mung bean yield. This study assesses the physiological and yield-related responses of ten diverse mung bean genotypes grown under three temperature regimes (34/25 °C, 39/30 °C, and 42/30 °C) in three growth chambers. We found significant genetic variability in phenological, physiological, and yield-related traits under control and heat stress conditions. Severe leaf damage, indicated by high cell membrane injury, reduced chlorophyll index, and diminished chlorophyll fluorescence, was observed under 39/30 °C and 42/30 °C conditions. Similarly, significant reductions in yield component traits, including effective pods per plant, total seeds per plant, single-seed weight, and seed yield per plant, were evident in the tested genotypes under 39/30 °C and 42/30 °C conditions. Correlation analysis suggested that selecting genotypes with higher chlorophyll index and increased canopy temperature depression could help identify mung bean varieties with enhanced pod and seed yields under heat stress. Clustering analysis identified genotypes PI 425425, PI 425238, and PI 363361 as potential candidates for breeding programs to develop climate-resilient cultivars., Competing Interests: Declarations. Competing interests: The authors declare no competing interests. Ethical approval: We have permission to collect Vigna radiata (L.). The experiment complied with relevant institutional, national, and international guidelines and legislation., (© 2025. The Author(s).)

Purpose: Cowpea ( Vigna unguiculata (L.) Walp.) is a major legume crops for human consumption and livestock feed in tropical regions. Although its importance, the crop's production is subjected to numerous constraints, raising the need to develop outstanding genotypes. In this line, this study assesses the effects of gamma irradiation doses on cowpea genotypes to determine the LD50 and its effects on agro-morphological parameters., Materials and Methods: Healthy dry seeds of three cowpea genotypes, Bambey 21, Me51-M4-39M9, and Ndout violet pods (VP), were exposed to four doses of gamma-rays 0, 200, 300, and 400 Gy. Qualitative and quantitative parameters were evaluated since germination, and a two-way analysis of variance (ANOVA) was performed on the means of quantitative traits using R software., Results: The results revealed that the LD50 on seed germination and plant survival ranged from 579 and 446.25 Gy, in Me51-M4-39M9, respectively. These values varied significantly among genotypes and revealed that low doses of gamma irradiation stimulated germination speed and had a positive effect on the early flowering of Ndout VP. Higher doses of gamma irradiation induced more severe mutations, causing visible effects such as changes in leaf color (albino, xantha, viridis, and variegation) and phyllotaxis. The frequency of chlorophyll mutants induced by gamma irradiation was found to be dose-genotype/dependent, with Bambey 21 being the most sensitive variety. Lower doses induced desirable mutations such as stem pigmentation and seed hilum coloration on Bambey 21 and Me51-M4-39M9. It has also had a positive impact on seedling height and leaf number in Bambey 21 and Ndout VP. However, high irradiation doses lead to a significant reduction in certain quantitative traits, such as plant height (PH), leaf length (LL), leaf width (LW), pod width (PWD), pod weight (PW), seed width (SWD), and seed weight. Analysis of the phenotypic performance of quantitative traits allowed us to cluster the four doses by genotype into three groups., Conclusions: The optimum dose of gamma-irradiation in cowpea mutation breeding is genotype-dependent. The effects of gamma-irradiation on these traits and their relationships are highly dependent on the specific crop and genotype. Further research is needed to understand these effects underlying mechanisms and develop crop improvement strategies using gamma irradiation.

The mungbean yellow mosaic India virus (MYMIV, Begomovirus vignaradiataindiaense) causes Yellow Mosaic Disease (YMD) in mungbean (Vigna radiata L.). The biochemical assays including total phenol content (TPC), total flavonoid content (TFC), ascorbic acid (AA), DPPH (2,2-diphenyl-1-picrylhydrazyl), and FRAP (Ferric Reducing Antioxidant Power) were used to study the mungbean plants defense response to MYMIV infection. A wide range was recorded for the Area Under Disease Progress Curve (AUDPC; 1.75-1266.98) and coefficient of infection (CI; 0.33-45.53). In YMD susceptible genotypes, significant variations were observed for TPC [2001.27-2834.13 mgGAE/100 g dry weight (DW)], TFC (252.65-341.30 mg/100 g DW), AA (40.33-64.69 mg/100 g DW), DPPH (32.11-53.47% scavenging effect DW), and FRAP (48.99-101.22 µmol Fe 2+ /g DW). Similarly, in resistant genotypes also wide range was recorded for TPC (1788.50-2286.38 mgGAE/100 g DW), TFC (206.12-337.32 mg/100 gDAS samples varied from 384.6.46-47.64% scavenging effect DW), and FRAP (53.68-114.24 µmol Fe 2+ /g DW). Except for FRAP, other studied parameters were in the lower range in the resistant genotypes than the susceptible genotypes. Genome-wide association studies (GWAS) of 132 genotypes have identified 31,953 single nucleotide polymorphism (SNPs). MLM (Mixed Linear Model) and BLINK (Bayesian-information and Linkage-disequilibrium Iteratively Nested Keyway) models have identified 119 shared SNPs for various biochemical traits and MYMIV resistance. The key candidate genes include VRADI09G06940 (YMD resistance, TIR-NBS-LRR class, chr. 9), VRADI01G05030 [flavonoid biosynthesis; MYB65 transcription factor (TF); chr. 1], VRADI03G07600 (phenol biosynthesis; GATA TF 16; chr. 3), VRADI04G08470 (ascorbic acid; heat shock protein 70 kDa protein; chr. 4), VRADI04G07510 (FRAP; subtilisin-like protease SBT1.9; chr. 4), and VRADI05G02870 (DPPH; vacuolar protein sorting-associated protein 2; chr. 5). The identified genomic resources will enhance mungbean genomics and facilitate the advancement of genomic-assisted breeding in mungbean., Competing Interests: Declarations. Conflict of interest: The authors affirm that they have no known financial or interpersonal conflicts that would have appeared to have an impact on the research presented in this study., (© 2024. The Author(s).)

Cowpea is a seed legume, important for food and nutritional security in Africa's arid and semi-arid zones. Despite its importance, cowpea is experiencing a loss of genetic diversity due to climate change. Therefore, this study aimed to evaluate the genetic variability of 33 cowpea mutant collections using 20 SSR and 13 ISSR markers. This analysis shows an average number of alleles of 5.15 for SSR and 6.7 for ISSR. The highest average genetic distance based on Nei's index among subgroups was 0.740 and the value of polymorphism information content varied from 0.02 to 0.23 for SSR and from 0.05 to 0.36 for ISSR. Our results revealed high genetic diversity based on the GD (0.126), Fst (0.513), and Shannon information index (0.246). The population structure analysis showed 3 and 4 clusters for ISSR and SSR markers, respectively. Genetic variation, as assessed by analysis of molecular variance, mostly indicates higher genetic diversity within the population than among populations. The hierarchical clustering of combined SSR and ISSR markers grouped the accessions into four groups, supporting the STRUCTURE analysis results. Additionally, the combination of SSR and ISSR provided better information on the level of genetic diversity, and population structure, and was more effective in determining the relationship between cowpea collection. This study enhances our understanding of the genetic organization of our mutant collection which can be used in breeding programs in the era of climate change., Competing Interests: Declarations. Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

Background: Charcoal Rot (CR) poses a significant threat to mung bean crops by reducing yield, making the development of resistant varieties crucial for stable production and food security. This study evaluated 19 newly identified mung bean landraces using biochemical traits and SSR markers, revealing genetic variability, CR disease reactions, and traits influencing yield and resistance, which provide valuable insights for breeding CR-resistant, high-yielding varieties., Methods and Results: Mung bean landraces were evaluated for their response to CR using 4 biochemical parameters, and 10 SSR markers to assess genetic variability and disease resistance. The results revealed substantial variability in morpho-quantitative traits, and showed a significant variation in CR disease reaction (21% resistance, and 16% moderately resistance). Biochemical characterization suggested that, phenolic content (PHE), Peroxidase (POX) and polyphenol oxidase (PPO) activities exhibited narrow ranges, suggesting more uniformity in these biochemical traits under CR stress. Yield (YLD) showed a positive correlation with the number of pods per plant (NPDP) (0.459), PPO (0.912), PHE (0.867), and total chlorophyll (TCL) (0.864), but showed a negative correlation with POX (-0.64), indicating their positive influence on productivity. Conversely, CR resistance was strongly negatively correlated with YLD (-0.86). Moreover, as per the principal component analysis (PCA), 80.5% of the total variance was explained by the first three principal components. However, molecular characterization suggested the PIC values ranged from 0.281 to 0.871, with an average 0.58 indicating moderate to high polymorphism. Principal coordinate analysis (PCoA) grouped landraces based on their genetic makeup under CR stress, and the first three axes explained most of the variation (82.03%). Phylogenetic tree analysis confirmed the PCoA groupings with similarity coefficient varied from 0.57 to 0.98, suggesting the landraces within a cluster had lower genetic distances, and resistant and moderately CR resistant landraces fell into separate clusters., Conclusion: The findings can be effectively utilized to develop CR-resistant mung bean varieties with enhanced productivity, contributing to stable mung bean production and food security., Competing Interests: Declarations. Ethical approval: This article does not contain any studies with human participants or animals performed by any of the authors. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

Background: Rice bean (Vigna umbellata), an underrated legume crop, demonstrates strong adaptability to poor soil fertility and has significant potential to enhance global food security. It is valuable both as a vegetable and fodder crop due to its high protein content, essential fatty acids, and micronutrients. Despite the sequencing of a high-quality genome of rice bean, its mitochondrial genome (mitogenome) sequence has not yet been reported., Results: For the first time, the rice bean mitogenome was assembled and annotated using PacBio HiFi sequencing and Geseq software. The mitogenome is a circular molecule with a length of 404,493 bp, containing 32 protein-coding genes, 17 tRNAs, and 3 rRNAs. Codon usage and sequence repeats were also determined. Six gene migration events from the chloroplast to the mitogenome were detected in rice bean. A phylogenetic analysis, including the rice bean mitogenome and 25 other taxa (23 of which are Fabales species), clarified the evolutionary and taxonomic status of rice bean. Additionally, a collinearity analysis of seven Fabales mitogenomes revealed high structural variability. In total, 473 RNA editing sites in protein-coding genes were identified., Conclusions: This study presents the first sequencing, assembly, annotation, and analysis of the rice bean mitogenome, providing valuable background information for understanding the evolution of this species. These findings lay the groundwork for future genetic studies and molecular breeding efforts aimed at improving rice bean., Competing Interests: Declarations. Ethics approval and consent to participate: The plant materials used in the study were collected under permission. The collection of plant materials and use comply with relevant institutional, national or international guidelines and legislation. This article does not contain any studies with human participants or animals and does not involve any endangered or protected species. Consent for publication: All authors consistently consent to publish the article. Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

Background: Mungbean ( Vigna radiata ) is one of the most socio-economically important leguminous food crops of Asia and a rich source of dietary protein and micronutrients. Understanding its genetic makeup is crucial for genetic improvement and cultivar development., Methods: In this study, we combined single-tube long-fragment reads (stLFR) sequencing technology with high-throughput chromosome conformation capture (Hi-C) technique to obtain a chromosome-level assembly of V. radiata cultivar 'KUML4'., Results: The final assembly of the V. radiata genome was 468.08 Mb in size, with a scaffold N50 of 40.75 Mb. This assembly comprised 11 pseudomolecules, covering 96.94% of the estimated genome size. The genome contained 253.85 Mb (54.76%) of repetitive sequences and 27,667 protein-coding genes. Our gene prediction recovered 98.3% of the highly conserved orthologs based on Benchmarking Universal Single-Copy Orthologs (BUSCO) analysis. Comparative analyses using sequence data from single-copy orthologous genes indicated that V. radiata diverged from V. mungo approximately 4.17 million years ago. Moreover, gene family analysis revealed that major gene families associated with defense responses were significantly expanded in V. radiata ., Conclusion: Our chromosome-scale genome assembly of V. radiata cultivar KUML4 will provide a valuable genomic resource, supporting genetic improvement and molecular breeding. This data will also be valuable for future comparative genomics studies among legume species., Competing Interests: The authors declare there are no competing interests., (©2024 Khanbo et al.)

Oxidosqualene cyclases (OSCs) are important regulatory enzymes involved in cyclization reactions of 2, 3-oxidosqualene to form triterpenes and sterols. This study presents the identification and characterization of three OSC genes, a β - amyrin synthase (VuβAS), a lupeol synthase (VuLUS) and a cycloartenol synthase (VuCAS) in Vigna unguiculata, an edible leguminous plant with high nutritional and nutraceutical value. Phylogenetic analysis showed that the VuβAS, VuLUS and VuCAS were clustered within the clades of previously characterized β - amyrin synthases, lupeol synthases and cycloartenol synthases. Heterologous expression in Saccharomyces cerevisiae and Gas Chromatography - Mass Spectrometry (GC - MS) analysis in different plant stages confirmed their specific functions. VuβAS showed higher expression in roots from early germinating seedlings to older plants (4-day to 28-day), while VuLUS expression levels were higher in the roots of older plants only (14-day to 28-day). VuCAS expression was increased in all the tissues of 4-day seedlings, with a peak in stem and leaves and a lower accumulation in radicles. These findings revealed the presence and function of OSC genes in V. unguiculata, and future research could lead to the discovery of promising biologically active compounds., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Adzuki bean, an underutilized grain legume, has a significant potential for enhancing food and nutritional security. The main obstacles to developing new cultivars and promoting the adzuki bean as a mainstream pulse crop are a lack of awareness about its potential and insufficient information on crop its genetic diversity. Here, we aimed to explore the untapped potential of adzuki bean germplasm by evaluating its agro-morphological traits and diversity at the molecular level and also to identify trait-specific germplasm by utilizing 100 adzuki bean accessions conserved in the Indian National Genebank. Significant variations was recorded for the morphological traits and identified promising accessions exhibiting desirable traits, such as early flowering (IC341945, EC340257 and EC340283), number of primary branches (IC341945 and IC469175), number of clusters per plant (EC000264, IC167611 and IC341939), number of pods per plant (IC469175, EC34264, EC000264), early maturity (EC340283; EC120460; IC341941) and number of seeds per pod (EC340240, IC455396 and IC341955). Molecular characterization of diverse accessions using 22 polymorphic SSR markers identified a total of 50 alleles, with a mean of 2.27 alleles per loci. The polymorphic information content (PIC) ranged from 0.03 to 0.46, indicating informativeness of markers in distinguishing diverse accessions. Further, the gene diversity among the accessions ranged from 0.03 to 0.57 with a mean of 0.19. Population structure analysis grouped the accessions into three genetic groups, supported by Principal Coordinate Analysis (PCoA) and a phylogenetic tree. Additionally, Analysis of Molecular Variance (AMOVA) confirmed a substantial genetic diversity among the adzuki bean accessions. Thus, the combined assessment of agro-morphological traits and molecular markers effectively distinguished adzuki bean accessions and provided valuable insights in understanding untapped variation at both morphological and molecular levels. The promising accessions identified in the study hold potential for integration into legume improvement programs through introgression breeding, contributing to the development of adzuki bean varieties with target trait., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Deshahalli Divakara et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

The widespread use of S-metolachlor (ME) in agriculture to suppress weeds and boost crop yields, particularly in cultivating Vigna angularis, is well established. However, the application of organosilicon adjuvants with herbicides has potential threats to non-target crops. This study investigates the toxicity symptoms and mechanisms when V. angularis is exposed to ME in conjunction with a common organosilicon adjuvant. Results indicate that ME inhibits the growth of V. angularis seedlings, and adding adjuvants could aggravate the negative effects of ME. According to the growth index of seedlings, the adjuvant increased the toxicity of ME by 84-96 %. Additionally, the chlorophyll content, root permeability, and antioxidant indicators in the seedlings were also adversely affected. Integrated metabolomics and transcriptomics analyses reveal that differentially abundant metabolites (DAMs) and differentially expressed genes (DEGs) are mainly enriched in four ways: "lysine degradation," "ABC transporters," "phenylalanine metabolism," and "monoterpenoid biosynthesis." The metabolic pathways and gene regulatory network involving 11 DAMs and 22 DEGs are associated with the physiological processes affected by ME and the adjuvant. This study provides guidance for the application of herbicides and their adjuvants in agricultural production to minimize adverse effects on non-target crops., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Key Message: QTL-seq, linkage mapping, and whole-genome resequencing revealed a new locus (qCLS5.1) controlling Cercospora canescens resistance in mungbean and Receptor-like protein 12 (RLP12) genes as candidate genes for the resistance. Cercospora leaf spot (CLS) disease, caused by Cercospora canescens, is a common disease of mungbean (Vigna radiata). In this study, the genetics of CLS resistance was investigated in a new source of resistance (accession V2817) and the resistance was finely mapped to identify candidate genes. F 2 and F 2:3 populations of the cross V1197 (susceptible) × V2718 and a BC 1 F 1 population of the cross V1197 × (V1197 × V2817) were used in this study. Segregation analysis suggested that the resistance is controlled by a single dominant gene. QTL-seq using F 2 individuals revealed that a single QTL (designated qCLS5.1) on chromosome 5 controlled the resistance. The qCLS5.1 was confirmed in the F 2:3 and BC 1 F 1 populations by QTL analysis. Fine mapping using 978 F 2 individuals localized qCLS5.1 to a 48.94 Kb region containing three tandemly duplicated Receptor-like protein 12 (RLP12) genes. Whole-genome resequencing and alignment of V1197 and V2817 revealed polymorphisms causing amino acid changes and premature stop codons in the three RLP12 genes. Collectively, these results show that qCLS5.1 is a new locus for CLS resistance in mungbean, and a cluster of RLP12 genes are candidate genes for the resistance. The new locus qCLS5.1 will be useful for molecular breeding of durable CLS-resistant mungbean cultivars., Competing Interests: Declarations. Conflict of interest: The authors declare that they have no conflict of interest., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Cytochrome c oxidase (COX) is a crucial mitochondrial enzyme in the electron transport chain of plants, implicated in energy production and stress responses. Despite its importance, the function of COX in leguminous plants, especially under heavy metal stress like cadmium (Cd), remains understudied., Methods and Results: In this study, COX genes (COX s) were identified based on the genome annotation file in mung bean (Vigna radiata (Linn.) R. Wilczek), and the gene structure, physicochemical properties and systematic relationships of the relevant amino acid sequences were analyzed by using bioinformatics method. The effects of Cd on the transcription levels and activities of COX in mung bean roots, stems, and leaves were detected to understand the mechanism of COX in mung bean in response to cadmium (Cd) stress. Transcriptome sequencing revealed tissue-specific expression with roots showed the highest levels. Cd stress significantly altered the expression and activity of VrCOXs, particularly in roots and stems, with varied responses among different genes., Conclusions: The differential response of VrCOX s to Cd stress indicates a role in the plant stress tolerance mechanism. The study provides insights into the function of COXs in legumes and a foundation for further research into Cd tolerance mechanisms, which could be vital for enhancing legume production and ensuring food safety in contaminated environments., Competing Interests: Declarations. Ethics approval and consent to participate: Not applicable. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

Blackgram ( Vigna mungo L. Hepper) production is hindered by mungbean yellow mosaic virus (MYMV) with disease incidence up to 85% in hot spot locations of Tamil Nadu, India. Field screening of 50 genotypes identified Mash 114 as resistant and CO 5 as susceptible cultivars. To understand the resistance mechanism, temporal metabolome variations of resistant (RC) and susceptible (SC) cultivars were assessed at 3, 6, and 12 days post-inoculation with MYMV via whitefly transmission using GC-MS. The study included aviruliferous whitefly and healthy controls. Data analysis identified 98 differential compounds across various metabolic groups. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) revealed distinct metabolic profiles, with RC accumulating antiviral terpenoids such as ursolic acid, betulin, and umbelliprenin, while SC upregulated lipids and fatty acids favoring virus replication. These findings provide insights for breeders to identify resistant sources and pave the way for improved MYMV management strategies using antiviral products.

Selenium (Se) and zinc (Zn) deficiencies have become serious global food security and public health problems. Biofortification through foliar fertilizer is a nonspecific, low-tech, and cost-effective strategy. Se and Zn have overlapping physiological roles and interacting relationships in plants. Mung bean is superior for Se enrichment and an excellent Zn carrier. However, the molecular mechanism underlying the interaction between Se and Zn in the mung bean remains unclear. Herein, Se and Zn accumulation, antioxidant activities, physiological determination, and transcriptomic analysis were performed under both Se and Zn treatments. Common essential roles of Se and Zn in mung bean were reflected by the comprehensively altered ten physiological indexes under both Se2 (24 g·ha -1 ) and Zn1 (1.2 kg·ha -1 ) treatments. Overlapping transcriptome changes and common DEGs in two compared groups revealed that the upregulated expression of sulfate transporters (SULTRs), phosphate transporters (PHTs), and Zinc-regulated/Iron-regulated-like protein (ZIP) family genes under Se and Zn treatments directly promoted both Se and Zn intakes. Furthermore, the altered Se/Sulfur, nitrogen, and carbohydrate metabolisms are closely interlinked with the uptake and assimilation of Se and Zn via the 20 key genes that we filtered through the protein-protein interaction (PPI) network analysis. Further analysis indicated that l-methionine γ-lyase (E 4.4.1.11) genes may play an important role in the transamination of selenomethionine and its derivatives; glutamine synthetase (GS), nitrate reductase (NR), and starch synthase (SS) genes may regulate the nitrogen assimilation and carbohydrate metabolism, which provide more carriers for Se and Zn; glutathione peroxidase (GPx), glutamate-cysteine ligase catalytic subunit (GCLC), and serine acetyltransferase (SAT) genes may accelerate the GSH-GSSH cycle and promote Se and Zn storages. This study provides new molecular insights into the comprehensive improvement of the nutritional quality of mung beans in Se and Zn biofortification productions.

Mung bean (Vigna radiata L.), a widely cultivated legume, belongs to the Fabaceae family's Papilionoideae subfamily. Although Phosphatidylethanolamine-binding protein (PEBP) genes have been identified in several plant species, their presence and function in mung bean remain largely unexplored. In this study, we identified seven VrPEBP genes from mung bean and classified them into four clades: FT, MFT, TFL and FT-like. Cis-regulatory element analysis revealed that VrPEBP genes may play a role in light, hormone, and stress responses. Quantitative real-time PCR (qRT-PCR) analysis indicated that VrPEBPs were constitutively expressed in various tissues. However, tissue-specific expression patterns were observed among VrPEBP genes. Under short-day (SD) conditions, VrFT1 and VrMFT1 exhibited significantly higher expression levels than under long-day (LD) conditions at 8 and 4 h, respectively. Conversely, VrTFL2 and VrTFL3 showed significantly higher expression levels under LD conditions compared to SD conditions at 8 and 12 h, respectively. The varied expression patterns of these genes under different photoperiod suggest their potential involvement in the photoperiodic regulation of flowering in mung bean. Additionally, phenotypic analysis of transgenic Arabidopsis plants overexpressing VrFT1 revealed higher expression levels under SD conditions and predicted its role in promoting flowering. These results provide valuable insights into the evolution and function of PEBP genes in mung bean and lay the foundation for further research on their regulatory mechanisms and potential applications in mung bean improvement., (© 2024. The Author(s).)

Node Inception (NIN) plays a crucial role in legume symbiosis by participating in both infection and nodule formation processes. However, its specific function in mungbean (Vigna radiata) remains poorly understood. This study aimed to functionally characterize the VrNIN1 gene in mungbean through an enhanced hairy root transformation approach. Examination of proVrNIN1: GUS hairy roots via GUS staining indicated the expression of VrNIN1 in later root promodia, nodule primordia, and nodules. Phenotypic evaluation revealed that overexpression or silencing of VrNIN1 led to a significant reduction in nodule numbers in hairy roots compared to controls. Additionally, interaction between VrNIN1 and VrNNC1 was confirmed through yeast two-hybrid, luciferase complementation and Co-immunoprecipitation assays. VrNNC1 expression was observed in the vascular bundle and cortex of roots and root nodules, where it notably suppressed nodule formation in transgenic hairy roots. Furthermore, gene expression analysis demonstrated the involvement of VrNIN1 and VrNNC1 in regulating root nodulation by modulating the expression of VrRIC1 and VrEDOD40. This study not only optimized the genetic transformation system for hairy roots in mungbean, but also provided mechanistic insights into the regulatory role of VrNIN1 in root nodule symbiosis in mungbean., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Masson SAS. All rights reserved.)

Drought stress has become an important limiting factor in mung bean production, and NAC(NAM/ATAF/CUC) transcription factors are crucial for plant growth under stress conditions, so it is important to study the regulatory role of NAC transcription factors in mung bean under drought stress. In this investigation, VrNAC15, along with its promoter, was cloned, and its structure was meticulously analyzed. Using qPCR, we examined the tissue-specific expression patterns of VrNAC15, particularly under drought stress and ABA exposure. Additionally, We performed ectopic expression of VrNAC15 in Arabidopsis to assess its function.. Gene sequence analysis revealed that VrNAC15 has a total length of 1014 bp, encoding 337 amino acids. It contains a NAM domain, localizes within the nucleus, and exhibits transcriptional activation. Promoter analysis of VrNAC15 identified essential core promoter elements and cis-acting elements related to abscisic acid, methyl jasmonate, gibberellin, adversity stress, light, and metabolism. Expression analysis demonstrated the concentration of VrNAC15 in leaves, with significant alterations following ABA and drought treatments in mung beans. Cluster analysis revealed that VrNAC15 may enhanced drought tolerance in transgenic plants through its expression. Transgenic experiments supported these findings, showing that heterologous expression of VrNAC15 led to enhanced antioxidant and osmotic adjustment capabilities in Arabidopsis plants. This resulted in the maintenance of cell membrane structural integrity during drought stress and normal physiological and biochemical metabolic reactions within cells. This research provides valuable insights into the structural and functional characteristics of the VrNAC15, setting the stage for future endeavors in molecular breeding for improved drought resistance in mung beans., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: Calmodulin-binding transcription activator (CAMTA) is comprised of a group of transcription factors and plays an important role in the Ca 2+ signaling pathway, mediating various molecular responses via interactions with other transcription factors and binding to the promoter region of specific genes. Mung beans (Vigna radiata) are one of the most commonly consumed commodities in Asia. To date, CAMTA proteins have not been characterized in this important crop plant., Results: Eight paralogous VrCAMTA genes were identified and found to be distributed on five of the 11 chromosomes. The proteins possessed CG-1 DNA-binding domains with bipartite NLS signals, ankyrin domains, CaM-binding IQ motifs, and CaM-binding domain (CaMBD). The 2 kb upstream regions of VrCAMTA genes contained sequence motifs of abscisic acid-responsive elements (ABRE) and ethylene-responsive elements (ERE), and binding sites for transcription factors of the bZIP and bHLH domains. Analysis of RNA-seq data from a public repository revealed ubiquitous expression of the VrCAMTA genes, as VrCAMTA1 was expressed at the highest level in seedling leaves, whereas VrCAMTA8 was expressed at the lowest level, which agreed with the RT-qPCR analysis performed on the first true leaves. On day four after leaf emergence, all VrCAMTA genes were upregulated, with VrCAMTA1 exhibiting the highest degree of upregulation. In darkness on day 4, upregulation was not observed in most VrCAMTA genes, except VrCAMTA7, for which a low degree of upregulation was found, whereas no difference was found in VrCAMTA8 expression between light and dark conditions. Treatment with calcium ionophores enhanced VrCAMTA expression under light and/or dark conditions at different times after leaf emergence, suggesting that calcium signaling is involved in the light-induced upregulation of VrCAMTA gene expression., Conclusions: The expression dependence of nearly all VrCAMTA genes on light and calcium signaling suggests their possible differential but likely complementary roles during the early stages of mung bean growth and development., (© 2024. The Author(s).)

Yellow mosaic disease (YMD) is a major constraint for the low productivity of mungbean, mainly in South Asia. Addressing this issue requires a comprehensive approach, integrating field and challenge inoculation evaluations to identify effective solutions. In this study, an infectious clone of Begomovirus vignaradiataindiaense (MYMIV) was developed to obtain a pure culture of the virus and to confirm resistance in mungbean plants exhibiting resistance under natural field conditions. The infectivity and efficiency of three Agrobacterium tumefaciens strains (EHA105, LBA4404, and GV3101) were evaluated using the susceptible mungbean genotype PS16. Additionally, a recombinant inbred line (RIL) population comprising 175 lines derived from Pusa Baisakhi (MYMIV susceptible) and PMR-1 (MYMIV resistant) cross was developed and assessed for YMD response. Among the tested Agrobacterium tumefaciens strains, EHA105 exhibited the highest infectivity (84.7%), followed by LBA4404 (54.7%) and GV3101 (9.80%). Field resistance was evaluated using the coefficient of infection (CI) and area under disease progress curve (AUDPC), identifying seven RILs with consistent resistant reactions (CI≤9) and low AUDPC (≤190). Upon challenge inoculation, six RILs exhibited resistance, while RIL92 displayed a resistance response, with infection occurring in less than 10% of plants after 24 to 29 days post inoculation (dpi). Despite some plants remaining asymptomatic, MYMIV presence was confirmed through specific PCR amplification of the MYMIV coat protein (AV1) gene. Quantitative PCR revealed a very low relative viral load (0.1-5.1% relative fold change) in asymptomatic RILs and the MYMIV resistant parent (PMR1) compared to the susceptible parent (Pusa Baisakhi). These findings highlight the potential utility of the developed infectious clone and the identified MYMIV-resistant RILs in future mungbean breeding programs aimed at cultivating MYMIV-resistant varieties., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Kumari et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

The symbiotic relationship between legumes and rhizobia is known to be influenced by specific rhizobial type III effectors (T3Es) in certain cases. In this study, we present evidence that the symbiosis between Vigna radiata and Bradyrhizobium elkanii USDA61 is controlled by a T3E called NopP2, and this interaction is highly dependent on the genetic makeup of the host plant. NopP2 plays a crucial role in promoting nodulation in various V. radiata varieties. Additionally, NopP2 is essential for early infection and the formation of nodules in compatible plants. Through evolutionary analysis, we discovered that bradyrhizobial NopPs can be categorized into two distinct clusters: NopP1 and NopP2. Furthermore, both types of bradyrhizobial NopPs were conserved within their respective groups. Our findings suggest that NopP2 serves as a mechanism for optimizing the symbiotic relationship between V. radiata and B. elkanii USDA61 by interacting with the pathogenesis related-10 (PR10) protein and reducing effector-triggered immunity (ETI) responses., (© 2024. The Author(s).)

Background: The discussion surrounding biological diversity has reached a critical point with the introduction of Nigeria's first transgenic food crop, the pod borer-resistant (PBR) cowpea. Questions have been raised about the potential risks of the transgenic Maruca vitrata -resistant cowpea to human health and beneficial insects. Public apprehension, coupled with social activists' calling for the removal of this crop from the nation's food market, persists. However, there is a lack of data to counter the assertion that cultivating PBR cowpea may have adverse effects on biodiversity and the overall ecological system. This research, with its multifaceted objective of examining the environmental safety of PBR cowpea and assessing its impact on biodiversity compared to its non-transgenic counterpart, IT97KN, is of utmost importance in providing the necessary data to address these concerns., Methods: Seeds for both the transgenic PBR cowpea and its isoline were obtained from the Institute for Agricultural Research (IAR) Zaria before planting at various farm sites (Addae et al., 2020). Throughout the experiment, local cultural practices were strictly followed to cultivate both transgenic and non-transgenic cowpeas. Elaborate taxonomic keys were used to identify arthropods and other non-targeted organisms. Principal component analysis (PCA) was used to evaluate potential modifications in all ecological niches of the crops. The lmer function of the R package lme4 was used to analyze diversity indices, including Shannon, Pielou, and Simpson. The Bray-Curtis index was used to analyzed potential modifications in the dissimilarities of non-targeted organisms' communities., Results: Examination of ecological species abundance per counting week (CW) revealed no disruption in the biological properties of non-targeted species due to the cultivation of transgenic PBR cowpea. Analysis of species evenness and diversity indices indicated no significant difference between the fields of transgenic PBR cowpea and its isoline. Principal component analysis results demonstrated that planting PBR cowpea did not create an imbalance in the distribution of ecological species. All species and families observed during this study were more abundant in transgenic PBR cowpea fields than in non-transgenic cowpea fields, suggesting that the transformation of cowpea does not negatively impact non-targeted organisms and their communities. Evolution dynamics of the species community between transgenic and non-transgenic cowpea fields showed a similar trend throughout the study period, with no significant divergence induced in the community structure because of PBR cowpea planting. This study concludes that planting transgenic PBR cowpea positively influences biodiversity and the environment., Competing Interests: The authors declare there are no competing interests., (©2024 Isah et al.)

Cowpea ( Vigna unguiculata (L.) Walp.) is appreciated for its suitability for cultivation and obtaining good yields in relatively extreme farming conditions. It is resistant to high temperatures and drought. Moreover, food products prepared from Vigna are rich in many nutrients such as proteins, amino acids, carbohydrates, minerals, fiber, vitamins, and other bioactive compounds. However, in East and Southeast Asia, where the products of this crop are in demand, the climate is characterized by excessive humidity. Under these conditions, the vast majority of cowpea varieties tend to have indeterminate growth (elongated shoot length) and are unsuitable for mechanized harvesting. The molecular mechanisms for tolerance to high relative humidity remain the least studied in comparison with those for other abiotic stress factors (drought, heat, cold, flooding, etc.). The purpose of the work was to reveal and investigate differentially expressed genes in cowpea accessions having contrasting growth habits (determinate and indeterminate) under humid and drought conditions. We performed RNA-seq analysis using selected cowpea accessions from the VIR collection. Among the genotypes used, some have significant changes in their plant architecture in response to high relative humidity, while others were tolerant to these conditions. In total, we detected 1697 upregulated and 1933 downregulated genes. The results showed that phytohormone-related genes are involved in cowpea response to high relative humidity. DEGs associated with jasmonic acid signaling are proposed to be key contributors in the maintenance of compact architecture under humid conditions.

Aluminium (Al 3+ ) toxicity in acidic soils poses a significant challenge for crop cultivation and reduces crop productivity. The primary defense mechanism against Al 3+ toxicity involves the activation of organic acid secretion. In this study, responses of 9 Vigna mungo cultivars to Al 3+ toxicity were investigated, with a particular emphasis on the root system and crucial genes involved in Al 3+ tolerance using molecular cloning and expression analysis. Sensitive blackgram-KM2 cultivars exposed to 100-µM Al 3+ toxicity for 72 h exhibited a root-growth inhibition of approximately 66.17%. Significant loss of membrane integrity and structural deformative roots were found to be the primary symptoms of Al 3+ toxicity in blackgram. MATE (Multidrug and Toxic Compound Extrusion) and ALS3 (Aluminium Sensitive 3) genes were successfully cloned from a sensitive blackgram cv KM2 with phylogenetic analysis revealing their evolutionary relationship to Vigna radiata and Glycine max. The MATE gene is mainly localized in the plasma membrane, and highly expressed under Al 3+ , thus suggesting its role in transports of citrate-Al 3+ complexes, and detoxifying Al 3+ within plant cells. In addition, ALS3 was also induced under Al 3+ toxicity, which codes the UDP-glucose transporter and is required for the maintenance of ions homeostasis. In summary, this study highlights the understanding of Al 3+ toxicity and underlying molecular mechanisms linked to the efflux of organic acid in blackgram, ultimately aiding the framework for the development of strategies to enhance the resilience of blackgram and other pulse crops in Al-rich soils., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Adzuki bean (Vigna angularis) is a significant dietary legume crop that is prevalent in East Asia. It also holds traditional medicinal importance in China. In this study, we report a high-quality, chromosome-level genome assembly of adzuki bean obtained by employing Illumina short-read sequencing, PacBio long-read sequencing, and Hi-C technology. The assembly spans 447.8 Mb, encompassing 96.32% of the estimated genome, with contig and scaffold N50 values of 16.5 and 41.0 Mb, respectively. More than 98.2% of the 1,614 BUSCO genes were fully identified, and 25,939 genes were annotated, with 98.23% of them being functionally identifiable. Vigna angularis was estimated to diverge successively from Vigna unguiculata and Vigna radiata about 15.3 and 8.7 million years ago (Ma), respectively. This chromosome-level reference genome of Vigna angularis provides a robust foundation for exploring the functional genomics and genome evolution of adzuki bean, thereby facilitating advancements in molecular breeding of adzuki bean., (© 2024. The Author(s).)

Nondestructive plant phenotyping forms a key technique for unraveling molecular processes underlying plant development and response to the environment. While the emergence of high-throughput phenotyping facilities can further our understanding of plant development and stress responses, their high costs greatly hinder scientific progress. To democratize high-throughput plant phenotyping, we developed sets of low-cost image- and weight-based devices to monitor plant shoot growth and evapotranspiration. We paired these devices to a suite of computational pipelines for integrated and straightforward data analysis. The developed tools were validated for their suitability for large genetic screens by evaluating a cowpea (Vigna unguiculata) diversity panel for responses to drought stress. The observed natural variation was used as an input for a genome-wide association study, from which we identified nine genetic loci that might contribute to cowpea drought resilience during early vegetative development. The homologs of the candidate genes were identified in Arabidopsis (Arabidopsis thaliana) and subsequently evaluated for their involvement in drought stress by using available T-DNA insertion mutant lines. These results demonstrate the varied applicability of this low-cost phenotyping system. In the future, we foresee these setups facilitating the identification of genetic components of growth, plant architecture, and stress tolerance across a wide variety of plant species., Competing Interests: Conflict of interest statement. None declared., (© The Author(s) 2024. Published by Oxford University Press on behalf of American Society of Plant Biologists. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Background/Objectives : Hybridity authentication is an important component of quality assurance and control (QA/QC) in breeding programs. Here, we introduce HybridQC v1.0, a QA/QC software program specially designed for parental purity and hybridity determination. HybridQC rapidly detects molecular marker polymorphism between parents of a cross and utilizes only the informative markers for hybridity authentication. Methods: HybridQC is written in Python and designed with a graphical user interface (GUI) compatible with Windows operating systems. We demonstrated the QA/QC analysis workflow and functionality of HybridQC using Kompetitive allele-specific PCR (KASP) SNP genotype data for cowpea ( Vigna unguiculata ). Its performance was validated in other crop data, including sorghum ( Sorghum bicolor ) and maize ( Zea mays ). Results: The application efficiently analyzed low-density SNP data from multiple cowpea bi-parental crosses embedded in a single Microsoft Excel file. HybridQC is optimized for the auto-generation of key summary statistics and visualization patterns for marker polymorphism, parental heterozygosity, non-parental alleles, missing data, and F 1 hybridity. An added graphical interface correctly depicted marker efficiency and the proportions of true F 1 versus self-fertilized progenies in the data sets used. The output of HybridQC was consistent with the results of manual hybridity discernment in sorghum and maize data sets. Conclusions: This application uses QA/QC SNP markers to rapidly verify true F 1 progeny. It eliminates the extensive time often required to manually curate and process QA/QC data. This tool will enhance the optimization efforts in breeding programs, contributing to increased genetic gain.

The TATA-box binding protein (TBP) and TBP-associated factors (TAFs) constitute the transcription factor IID (TFIID), a crucial component of RNA polymerase II, essential for transcription initiation and regulation. Several TFIID subunits are shared with the Spt-Ada-Gcn5-acetyltransferase (SAGA) coactivator complex. Recent research has revealed the roles of TBP and TAFs in organogenesis and stress adaptation. In this study, we identified 1 TBP and 21 putative TAFs in the mungbean genome, among which VrTAF5 , VrTAF6 , VrTAF8 , VrTAF9 , VrTAF14 , and VrTAF15 have paralogous genes. Their potential involvement in abiotic stress responses was also investigated here, including high salinity, water deficit, heat, and cold. The findings indicated that distinct genes exerted predominant influences in the response to different abiotic stresses through potentially unique mechanisms. Specifically, under salt stress, VrTBP , VrTAF2 , and VrTAF15-1 were strongly induced, while VrTAF10 , VrTAF11 , and VrTAF13 acted as negative regulators. In the case of water-deficit stress, it was likely that VrTAF1 , VrTAF2 , VrTAF5-2 , VrTAF9 , and VrTAF15-1 were primarily involved. Additionally, in response to changes in ambient temperature, it was possible that genes such as VrTAF5-1 , VrTAF6-1 , VrTAF9-2 , VrTAF10 , VrTAF13 , VrTAF14b-2 , and VrTAF15-1 might play a dominant role. This comprehensive exploration of VrTBP and VrTAFs can offer a new perspective on understanding plant stress responses and provide valuable insights into breeding improvement.

In the current study, we have performed a comprehensive analysis of the Sodium Hydrogen Exchanger (NHX) gene family in Vigna mungo, and a total of 44 NHX genes were identified. A bimodal distribution based on domains, gene structure and phylogenetic analysis was evident. All intronpoor and intron-rich genes were clustered in clades I and II, respectively. Interestingly, all genes of subclade IIb were localized to vacuoles and possess only the NHX domain. The isoelectric point and trans-membrane domain analysis reflect the wide distribution of the NHX genes. Interestingly, Vm&#95;NHX2 and Vm&#95;NHX3 lacked trans-membrane domain but were found to interact with other NHX genes as well as vital salinity pathway genes, including calcium-mediated salt-responsive genes. The comparison of the mRNA sequences with that of V. marina, a halophytic species, reflects their independent evolution, majorly supporting the convergent evolution. The Ka/Ks ratio reflects the abundance of purifying selection supporting their conserved function during evolution. In our analysis, several abiotic stress and hormone-responsive elements and transcription factor binding sites were present in the promoter of the NHX genes. Further, the ion partitioning of a tolerant (K90) and a susceptible (K49) variety of V. mungo suggested that K90 managed the Na + /K + ratio more affluently, which was also supported by profiling of superoxide radicals, hydrogen peroxide, phenol, peroxidase activity and superoxide dismutase activity. From the expression, we identified five candidate Vm&#95;NHX genes, four of which, i.e. Vm&#95;NHX16, Vm&#95;NHX17, Vm&#95;NHX29 and Vm&#95;NHX33, were localized to the vacuolar and lysosomal membrane., (© 2024 Scandinavian Plant Physiology Society.)

Root-knot nematodes (Meloidogyne spp.) are plant parasites causing annual economic losses amounting to several billion US dollars worldwide. One of the most aggressive species is M. enterolobii, a growing threat to agriculture due to its broad host range and ability to overcome many known resistance genes. Mungbean, a nutritionally and economically valuable crop, is particularly vulnerable to nematodes and pathogens. However, research focusing on mungbean resistance to M. enterolobii is scarce, and the corresponding defense mechanisms are poorly understood. Here, we screened mungbean accessions and identified an accession strongly resistant to M. enterolobii. Transcriptome analysis revealed 2730 differentially expressed genes (DEGs) in this resistant accession (CPI106939) compared to 1777 in the susceptible accession (Crystal) 7 days after nematode inoculation. The gene ontology (GO) upregulated in CPI106939 with functions related to plant-pathogen interactions, plant hormone signaling, oxidative stress, and plant immunity. Plant defense-related genes (WRKY, PAL, MAPK, POD and PR) were also significantly induced in CPI106939. Metabolome analysis showed that four secondary metabolites related to phenylpropanoid metabolism and lignification were significantly enriched in CPI106939. The induced immune response and secondary metabolites may underpin the enhanced resistance to M. enterolobii, providing insight into the resistance mechanisms in accession CPI106939 as well as candidate genes controlling the interaction between mungbean and its nematode parasite. Our study therefore provides foundations for the breeding of new varieties with intrinsic M. enterolobii resistance., (© 2024 Scandinavian Plant Physiology Society.)

Premise: Vigna includes economically vital crops and wild species. Molecular systematic studies of Vigna species resulted in generic segregates of many New World (NW) species. However, limited Old World (OW) sampling left questions regarding inter- and intraspecific relationships in Vigna s.s., Methods: African species, including the putative sister genus Physostigma, were comprehensively sampled within the context of NW relatives. Maximum likelihood and Bayesian inference analyses of the chloroplast matK-trnK and nuclear ribosomal ITS/5.8 S (ITS) DNA regions were undertaken to resolve OW Vigna taxonomic questions. Divergence dates were estimated using BEAST to date key nodes in the phylogeny., Results: Analyses of matK and ITS data supported five clades of Vigna s.s.: subg. Lasiospron, a reduced subg. Vigna, subg. Haydonia, subg. Ceratotropis, an enlarged subg. Plectrotropis, and a clade including V. kirkii and V. stenophylla. Genome size estimates of 601 Mb for V. kirkii are near the overall mean of the genus, whereas V. stenophylla had a larger genome (810 Mb), similar to some Vigna subg. Ceratotropis or Plectrotropis species., Conclusions: Former subg. Vigna is reduced to yellow- and blue-flowered species and subg. Plectrotropis is enlarged to mostly all white-, pink-, and purple-flowered species. The age of the split between NW and OW Vigna lineages is ~6-7 Myr. Genome size estimates cannot rule out a polyploid or hybrid origin for V. stenophylla, potentially involving extinct lineage ancestors of Vigna subg. Ceratotropis or Plectrotropis, as indicated by network and phylogenetic analyses. Taxonomic revisions are suggested based on these results., (© 2024 Botanical Society of America.)

The genus Vigna (Leguminosae) comprises about 150 species grouped into five subgenera. The present study aimed to improve the understanding of karyotype diversity and evolution in Vigna, using new and previously published data through different cytogenetic and DNA content approaches. In the Vigna subgenera, we observed a random distribution of rDNA patterns. The 35S rDNA varied in position, from terminal to proximal, and in number, ranging from one (V. aconitifolia, V. subg. Ceratotropis) to seven pairs (V. unguiculata subsp. unguiculata, V. subg. Vigna). On the other hand, the number of 5S rDNA was conserved (one or two pairs), except for V. radiata (V. subg. Ceratotropis), which had three pairs. Genome size was relatively conserved within the genus, ranging from 1C = 0.43 to 0.70 pg in V. oblongifolia and V. unguiculata subsp. unguiculata, respectively, both belonging to V. subg. Vigna. However, we observed a positive correlation between DNA content and the number of 35S rDNA sites. In addition, data from chromosome-specific BAC-FISH suggest that the ancestral 35S rDNA locus is conserved on chromosome 6 within Vigna. Considering the rapid diversification in the number and position of rDNA sites, such conservation is surprising and suggests that additional sites may have spread out from this ancestral locus., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)

Background: The symbiosis among plants, rhizobia, and arbuscular mycorrhizal fungi (AMF) is one of the most well-known symbiotic relationships in nature. However, it is still unclear how bilateral/tripartite symbiosis works under resource-limited conditions and the diverse genetic backgrounds of the host., Results: Using a full factorial design, we manipulated mungbean accessions/subspecies, rhizobia, and AMF to test their effects on each other. Rhizobia functions as a typical facilitator by increasing plant nitrogen content, plant weight, chlorophyll content, and AMF colonization. In contrast, AMF resulted in a tradeoff in plants (reducing biomass for phosphorus acquisition) and behaved as a competitor in reducing rhizobia fitness (nodule weight). Plant genotype did not have a significant effect on AMF fitness, but different mungbean accessions had distinct rhizobia affinities. In contrast to previous studies, the positive relationship between plant and rhizobia fitness was attenuated in the presence of AMF, with wild mungbean being more responsive to the beneficial effect of rhizobia and attenuation by AMF., Conclusions: We showed that this complex tripartite relationship does not unconditionally benefit all parties. Moreover, rhizobia species and host genetic background affect the symbiotic relationship significantly. This study provides a new opportunity to re-evaluate the relationships between legume plants and their symbiotic partners., (© 2024. The Author(s).)

Cadmium (Cd), one of the most phytotoxic heavy metals, is a major contributor to yield losses in several crops. Silicon (Si) is recognized for its vital role in mitigating Cd toxicity, however, the specific mechanisms governing this mitigation process are still not fully understood. In the present study, the effect of Si supplementation on mungbean (Vigna radiata (L.) Wilczek) plants grown under Cd stress was investigated to unveil the intricate pathways defining Si derived stress tolerance. Non-invasive leaf imaging technique revealed improved growth, biomass, and photosynthetic efficiency in Si supplemented mungbean plants under Cd stress. Further, physiological and biochemical analysis revealed Si mediated increase in activity of glutathione reductase (GR), ascorbate peroxidase (APX), and catalase (CAT) enzymes involved in reactive oxygen species (ROS) metabolism leading to mitigation of cellular damage and oxidative stress. Untargeted metabolomic analysis using liquid chromatography coupled with mass spectrometry (LC-MS/MS) provided insights into Si mediated changes in metabolites and their respective pathways under Cd stress. Alteration in five different metabolic pathways with major changes in flavanols and flavonoids biosynthesis pathway which is essential for controlling plants antioxidant defense system and oxidative stress management were observed. The information reported here about the effects of Si on photosynthetic efficiency, antioxidant responses, and metabolic changes will be helpful in understanding the Si-mediated resistance to Cd stress in plants., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Adzuki bean (Vigna angularis) is an important legume crop cultivated in over 30 countries worldwide. We developed a high-quality chromosome-level reference genome of adzuki bean cultivar Jingnong6 by combining PacBio Sequel long-read sequencing with short-read and Hi-C technologies. The assembled genome covers 97.8% of the adzuki bean genome with a contig N50 of approximately 16 Mb and a total of 32 738 protein-coding genes. We also generated a comprehensive genome variation map of adzuki bean by whole-genome resequencing (WGRS) of 322 diverse adzuki beans accessions including both wild and cultivated. Furthermore, we have conducted comparative genomics and a genome-wide association study (GWAS) on key agricultural traits to investigate the evolution and domestication. GWAS identified several candidate genes, including VaCycA3;1, VaHB15, VaANR1 and VaBm, that exhibited significant associations with domestication traits. Furthermore, we conducted functional analyses on the roles of VaANR1 and VaBm in regulating seed coat colour. We provided evidence for the highest genetic diversity of wild adzuki (Vigna angularis var. nipponensis) in China with the presence of the most original wild adzuki bean, and the occurrence of domestication process facilitating transition from wild to cultigen. The present study elucidates the genetic basis of adzuki bean domestication traits and provides crucial genomic resources to support future breeding efforts in adzuki bean., (© 2024 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.)

Pre-harvest sprouting (PHS) is one of the important abiotic stresses in mungbean which significantly reduces yield and quality of the produce. This study was conducted to evaluate the genetic variability for tolerance to pre-harvest sprouting in diverse mungbean genotypes while simultaneously deciphering the association of yield contributing traits with PHS. Eighty-three diverse mungbean genotypes (23 released varieties, 23 advanced breeding lines and 37 exotic germplasm lines) were investigated for tolerance to PHS, water imbibition capacities by pods, pod and seed physical traits. Wide variation in PHS was recorded which ranged between 17.8% to 81% (mean value 54.34%). Germplasm lines exhibited higher tolerance to PHS than the high-yielding released varieties. Correlation analysis revealed PHS to be positively associated with water imbibition capacity by pods (r = 0.21) and germinated pod % (r = 0.78). Pod length (r = -0.13) and seeds per pod (r = -0.13) were negatively influencing PHS. Positive associations between PHS and water imbibition capacity by pods, germinated pod % and 100-seed weight was further confirmed by multivariate analysis. Small-seeded genotypes having 100-seed weight <3 g exhibited higher tolerance to PHS compared to bold-seeded genotypes having 100-seed weight more than 3.5 g. Fresh seed germination among the selected PHS tolerant and susceptible genotypes ranged from 42% (M 204) to 98% (Pusa 1131). A positive association (r = 0.79) was recorded between fresh seed germination and PHS. Genotypes M 1255, M 145, M 422, M 1421 identified as potential genetic donors against PHS could be utilized in mungbean breeding programs., Competing Interests: The authors declare that they have no competing interests., (© 2024 Gupta et al.)

Background: The adzuki bean is a typical short-day plant and an important grain crop that is widely used due to its high nutritional and medicinal value. The adzuki bean flowering time is affected by multiple environmental factors, particularly the photoperiod. Adjusting the day length can induce flower synchronization in adzuki bean and accelerate the breeding process. In this study, we used RNA sequencing analysis to determine the effects of different day lengths on gene expression and metabolic characteristics related to adzuki bean flowering time., Methods: 'Tangshan hong xiao dou' was used as the experimental material in this study and field experiments were conducted in 2022 using a randomized block design with three treatments: short-day induction periods of 5 d (SD-5d), 10 d (SD-10d), and 15 d (SD-15d)., Results: A total of 5,939 differentially expressed genes (DEGs) were identified, of which 38.09% were up-regulated and 23.81% were down-regulated. Gene ontology enrichment analysis was performed on the target genes to identify common functions related to photosystems I and II. Kyoto Encyclopedia of Genes and Genomes enrichment analysis identified two pathways involved in the antenna protein and circadian rhythm. Furthermore, florescence was promoted by down-regulating genes in the circadian rhythm pathway through the blue light metabolic pathway; whereas, antenna proteins promoted flowering by enhancing the reception of light signals and accelerating electron transport. In these two metabolic pathways, the number of DEGs was the greatest between the SD-5d VS SD-15d groups. Real-time reverse transcription‒quantitative polymerase chain reaction analysis results of eight DEGs were consistent with the sequencing results. Thus, the sequencing results were accurate and reliable and eight genes were identified as candidates for the regulation of short-day induction at the adzuki bean seedling stage., Conclusions: Short-day induction was able to down-regulate the expression of genes related to flowering according to the circadian rhythm and up-regulate the expression of certain genes in the antenna protein pathway. The results provide a theoretical reference for the molecular mechanism of short-day induction and multi-level information for future functional studies to verify the key genes regulating adzuki bean flowering., Competing Interests: The authors declare that they have no competing interests., (© 2024 Dong et al.)

The Multidrug and toxic compound extrusion (MATE) and aluminium activated malate transporter (ALMT) gene families are involved in response to aluminium (Al) stress. In this study, we identified 48 MATE and 14 ALMT gene families in Vigna radiata genome and classified into 5 (MATE) and 3 (ALMT) clades by phylogenetic analysis. All the VrMATE and VrALMT genes were distributed across mungbean chromosomes. Tandem duplication was the main driving force for evolution and expansion of MATE gene family. Collinearity of mungbean with soybean indicated that MATE gene family is closely linked to Glycine max. Eight MATE transporters in clade 2 were found to be associated with previously characterized Al tolerance related MATEs in various plant species. Citrate exuding motif (CEM) was present in seven VrMATEs of clade 2. Promoter analysis revealed abundant plant hormone and stress responsive cis-elements. Results from quantitative real time-polymerase chain reaction (qRT-PCR) revealed that VrMATE19, VrMATE30 and VrALMT13 genes were markedly up-regulated at different time points under Al stress. Overall, this study offers a new direction for further molecular characterization of the MATE and ALMT genes in mungbean for Al tolerance., Competing Interests: Declaration of Competing Interest No potential conflict of interest was reported by the authors., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Drought stress following climate change is likely a scenario that will have to face crop growers in tropical regions. In mitigating this constraint, the best option should be the selection and use of resilient varieties that can withstand drought threats. Therefore, a pot experiment was conducted under greenhouse conditions at the Research and Teaching Farm of the Faculty of Agronomy and Agricultural Sciences of the University of Dschang. The objectives are to identify sensitive growth stage, to identify drought-tolerant genotypes with the help of yield-based selection indices and to identify suitable selection indices that are associated with yield under non-stress and stress circumstances. Eighty-eight cowpea genotypes from the sahelian and western regions of Cameroon were subjected to drought stress at vegetative (VDS) and flowering (FDS) stages by withholding water for 28 days, using a split plot design with two factors and three replications. Seed yields under stress (Ys) and non-stress (Yp) conditions were recorded. Fifteen drought indices were calculated for the two drought stress levels against the yield from non-stress plants. Drought Intensity Index (DII) under VDS and FDS were 0.71 and 0.84 respectively, indicating severe drought stress for both stages. However, flowering stage was significantly more sensitive to drought stress compared to vegetative stage. Based on PCA and correlation analysis, Stress Tolerance Index (STI), Relative Efficiency Index (REI), Geometric Mean Productivity (GMP), Mean Productivity (MP), Yield Index (YI) and Harmonic Mean (HM) correlated strongly with yield under stress and non-stress conditions and are therefore suitable to discriminate high-yielding and tolerant genotypes under both stress and non-stress conditions. Either under VDS and FDS, CP-016 exhibited an outstanding performance under drought stress and was revealed as the most drought tolerant genotype as shown by ranking, PCA and cluster analysis. Taking into account all indices, the top five genotypes namely CP-016, CP-021, MTA-22, CP-056 and CP-060 were identified as the most drought-tolerant genotypes under VDS. For stress activated at flowering stage (FDS), CP-016, CP-056, CP-021, CP-028 and MTA-22 were the top five most drought-tolerant genotypes. Several genotypes with insignificant Ys and irrelevant rank among which CP-037, NDT-001, CP-036, CP-034, NDT-002, CP-031, NDT-011 were identified as highly drought sensitive with low yield stability. This study identified the most sensitive stage and drought tolerant genotypes that are proposed for genetic improvement of cowpea., Competing Interests: The authors have declared that no competing interests exist, (Copyright: © 2024 Ngompe Deffo et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: Cowpea wilt is a harmful disease caused by Fusarium oxysporum, leading to substantial losses in cowpea production. Melatonin reportedly regulates plant immunity to pathogens; however the specific regulatory mechanism underlying the protective effect of melatonin pretreated of cowpea against Fusarium oxysporum remains known. Accordingly, the study sought to evaluate changes in the physiological and biochemical indices of cowpea following melatonin treated to facilitate Fusarium oxysporum resistance and elucidate the associated molecular mechanism using a weighted gene coexpression network., Results: Treatment with 100 µM melatonin was effective in increasing cowpea resistance to Fusarium oxysporum. Glutathione peroxidase (GSH-PX), catalase (CAT), and salicylic acid (SA) levels were significantly upregulated, and hydrogen peroxide (H 2 O 2 ) levels were significantly downregulated in melatonin treated samples in roots. Weighted gene coexpression network analysis of melatonin- and Fusarium oxysporum-treated samples identified six expression modules comprising 2266 genes; the number of genes per module ranged from 9 to 895. In particular, 17 redox genes and 32 transcription factors within the blue module formed a complex interconnected expression network. KEGG analysis revealed that the associated pathways were enriched in secondary metabolism, peroxisomes, phenylalanine metabolism, flavonoids, and flavonol biosynthesis. More specifically, genes involved in lignin synthesis, catalase, superoxide dismutase, and peroxidase were upregulated. Additionally, exogenous melatonin induced activation of transcription factors, such as WRKY and MYB., Conclusions: The study elucidated changes in the expression of genes associated with the response of cowpea to Fusarium oxysporum under melatonin treated. Specifically, multiple defence mechanisms were initiated to improve cowpea resistance to Fusarium oxysporum., (© 2024. The Author(s).)

Key Message: The investigation of MYMIV-infected mung bean leaf apoplast revealed viral genome presence, increased EVs secretion, and altered stress-related metabolite composition, providing comprehensive insights into plant-virus interactions. The apoplast, an extracellular space around plant cells, plays a vital role in plant-microbe interactions, influencing signaling, defense, and nutrient transport. While the involvement of apoplast and extracellular vesicles (EVs) in RNA virus infection is documented, the role of the apoplast in plant DNA viruses remains unclear. This study explores the apoplast's role in mungbean yellow mosaic India virus (MYMIV) infection. Our findings demonstrate the presence of MYMIV genomic components in apoplastic fluid, suggesting potential begomovirus cell-to-cell movement via the apoplast. Moreover, MYMIV infection induces increased EVs secretion into the apoplast. NMR-based metabolomics reveals altered metabolic profiles in both apoplast and symplast in response to MYMIV infection, highlighting key metabolites associated with stress and defense mechanisms. The data show an elevation of α- and β-glucose in both apoplast and symplast, suggesting a shift in glucose utilization. Interestingly, this increase in glucose does not contribute to the synthesis of phenolic compounds, potentially influencing the susceptibility of mung bean to MYMIV. Fructose levels increase in the symplast, while apoplastic sucrose levels rise significantly. Symplastic aspartate levels increase, while proline exhibits elevated concentration in the apoplast and reduced concentration in the cytosol, suggesting a role in triggering a hypersensitive response. These findings underscore the critical role of the apoplast in begomovirus infection, providing insights for targeted viral disease management strategies., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Mung bean (Vigna radiata L.) is an important warm-season grain legume. Adaptation to extreme environmental conditions, supported by evolution, makes mung bean a rich gene pool for stress tolerance traits. The exploration of resistance genes will provide important genetic resources and a theoretical basis for strengthening mung bean breeding. B-box (BBX) proteins play a major role in developmental processes and stress responses. However, the identification and analysis of the mung bean BBX gene family are still lacking., Results: In this study, 23 VrBBX genes were identified through comprehensive bioinformatics analysis and named based on their physical locations on chromosomes. All the VrBBXs were divided into five groups based on their phylogenetic relationships, the number of B-box they contained and whether there was an additional CONSTANS, CO-like and TOC1 (CCT) domain. Homology and collinearity analysis indicated that the BBX genes in mung bean and other species had undergone a relatively conservative evolution. Gene duplication analysis showed that only chromosomal segmental duplication contributed to the expansion of VrBBX genes and that most of the duplicated gene pairs experienced purifying selection pressure during evolution. Gene structure and motif analysis revealed that VrBBX genes clustered in the same group shared similar structural characteristics. An analysis of cis-acting elements indicated that elements related to stress and hormone responses were prevalent in the promoters of most VrBBXs. The RNA-seq data analysis and qRT-PCR of nine VrBBX genes demonstrated that VrBBX genes may play a role in response to environmental stress. Moreover, VrBBX5, VrBBX10 and VrBBX12 are important candidate genes for plant stress response., Conclusions: In this study, we systematically analyzed the genomic characteristics and expression patterns of the BBX gene family under ABA, PEG and NaCl treatments. The results will help us better understand the complexity of the BBX gene family and provide valuable information for future functional characteristics of specific genes in this family., (© 2024. The Author(s).)