The genus Vigna (Fabaceae) consists of five subgenera, and includes more than 100 wild species. In Vigna, 10 crops have been domesticated from three subgenera, Vigna, Plectrotropis, and Ceratotropis. The habitats of wild Vigna species are so diverse that their genomes could harbor various genes responsible for environmental stress adaptation, which could lead to innovations in agriculture. Since some of the gene bank Vigna accessions were unidentified and they seemed to be novel genetic resources, these accessions were identified based on morphological traits. The phylogenetic positions were estimated based on the DNA sequences of nuclear rDNA-ITS and chloroplast atpB-rbcL spacer regions. Based on the results, the potential usefulness of the recently described species V. indica and V. sahyadriana, and some wild Vigna species, i.e., V. aconitifolia, V. dalzelliana, V. khandalensis, V. marina var. oblonga, and V. vexillata, was discussed.

Mungbean yellow mosaic virus (MYMV) disease is one of the most vicious diseases of green gram and has been renowned in India for more than five decades. It is caused by a group of geminiviruses belonging to the genus, begomovirus of the family, Geminiviridae. They are transmitted through whitefly in a persistent manner. The economic losses due to this virus account up to 85% in green gram which is spreading faster towards newer areas. The escalating economic importance of MYMV has resulted in the call for accurate detection and identification procedures that inspire rigorous research efforts focussing on the biology, diversity and epidemiology of the virus, so that viable management strategies could be designed. Breeding for resistance or tolerance appears to be the best approach to control this disease. However, the commercially offered genotypes are only partially resistant. Therefore, the hunt for newer sources of disease resistance needs to be intensified. This review updates all the accessible information on MYMV and outlines the areas in which advance research is indispensable.

Though crossing wild relatives to modern cultivars is a usual means to introduce alleles of stress tolerance, an alternative is de novo domesticating wild species that are already tolerant to various kinds of stresses. As a test case, we chose Vigna stipulacea Kuntze, which has fast growth, short vegetative stage, and broad resistance to pests and diseases. We developed an ethyl methanesulfonate–mutagenized population and obtained three mutants with reduced seed dormancy and one with reduced pod shattering. We crossed one of the mutants of less seed dormancy to the wild type and confirmed that the phenotype was inherited in a Mendelian manner. De novo assembly of V. stipulacea genome, and the following resequencing of the F2 progenies successfully identified a Single Nucleotide Polymorphism (SNP) associated with seed dormancy. By crossing and pyramiding the mutant phenotypes, we will be able to turn V. stipulacea into a crop which is yet primitive but can be cultivated without pesticides.

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The objective of this research was to study the mode of inheritance of resistance to mungbean yellow mosaic virus (MYMV) in inter TNAU RED × VRM (Gg) 1 and intra KMG 189 × VBN (Gg) 2 specific crosses of mungbean. An infector row technique was used for evaluating parents, F 1 , F 2 and F 3 plants for MYMV resistance. No insecticide was sprayed in order to maintain the natural whitefly population in experimental field. In the field condition, only after 80% of plants showed MYMV incidence, and the scoring of the test materials was done by MYMV disease rating scale. According to the mean disease score, the mungbean genotypes were categorized into five groups resistant (R), moderately resistant (MR), moderately susceptible (MS), susceptible (S) and highly susceptible (HS). 3 (Susceptible): 1 (Resistance) was observed in all two crosses of all F 2 population and it showed that the dominance of susceptibility over the resistance and the results of the F 3 segregation (1:2:1) confirm the segregation pattern of the F 2 segregation. Collectively all the two crosses F 2 and F 3 generations results suggested that a single recessive gene is involved in resistance against the MYMV disease.

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In the present study, fifty-two mungbean (Vigna radiata) genotypes were evaluated for seven morphological traits at three different environments in South Indian state Tamil Nadu, namely Virinjipuram (E1), Eachangkottai (E2), and Bhavanisagar (E3) during Kharif 2017, 2018, and 2019, respectively. The data collected were subjected to variability and correlation analyses, followed by stability analysis using additive main effects and multiplicative interaction (AMMI) model, genotype and genotype × environment interaction effects (GGE) biplot. Variablility was observed among the genotypes for the following traits viz., plant height, days to fifty per cent flowering, number of pods per plant, pod length, number of seeds per pod, hundred seed weight and grain yield. Correlation analysis showed that the trait number of pods per plant was significantly associated with grain yield. The G × E was smaller than the genetic variation of grain yield as it portrayed the maximum contribution of genotypic effects (61.07%). GGE biplot showed E3 as a highly discriminating and representative environment. It also identified environment-specific genotypes viz., EC 396111 for E1, EC 396125 for E2 and EC 396101 for E3 environments. The genotypes with minimum genotype stability index (GSI) viz., V2802BG (7), HG 22 (13), and EC 396098 (13) were observed with wide adaptation and high yields across all the three environments. In summary, we identified stable genotypes adapted across environments for grain yield. These genotypes can be used as parent/pre-breeding materials in future mungbean breeding programs.

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