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Vigna stipulacea (Lam.) Kuntz., commonly known as Minni payaru is an underutilized legume species and has a great potential to be utilized as food crop. To evaluate and select the best germplasm to be harnessed in the breeding programme, we assessed the genetic diversity of V. stipulacea (94 accessions) conserved in the Indian National Genebank, based on morphological traits and microsatellite markers. Significant variation was recorded for the morphological traits studied. Euclidean distance using UPGMA method grouped all accessions into two major clusters. Accessions were identified for key agronomic traits such as, early flowering (IC331436, IC251436, IC331437); long peduncle length (IC553518, IC550531, IC553557, IC553540, IC550532, IC553564); and more number of seeds per pod (IC553529, IC622865, IC622867, IC553528). To analyse the genetic diversity among the germplasm 33 SSR primers were used anda total of 116 alleles were detected. The number of alleles varied from two to seven, with an average of 3.52 per loci. The polymorphic information content values varied from 0.20 to 0.74, with a mean of 0.40. The high number of alleles per locus and the allelic diversity in the studied germplasm indicated a relatively wider genetic base of V. stipulacea. Phylogenetic analysis clustered accessions into seven clades. Population structure analysis grouped them into five genetic groups, which were partly supported by PCoA and phylogenetic tree. Besides, PCoA and AMOVA also decoded high genetic diversity among the V. stipulacea accessions. Thus, morphological and microsatellite markers distinguished V. stipulacea accessions and assessed their genetic diversity efficiently. The identified promising accessions can be utilized in Vigna improvement programme through introgression breeding and/or can be used for domestication and enhanced utilization of V. stipulacea.

Thirty eight novel microsatellite markers (SSRs) specific to candidate genes involved in salt tolerance were developed for detection of genetic variations in 12 mungbean genotypes variably adapted to salt stress. A 100 out of 124 putative alleles were found polymorphic between wild and cultivated genotypes (inter-specific, 80.65%), 65 were within cultivars of mungbean (intra-specific, 52.42%) and 52 were within wild genotypes (inter-specific, 41.94%). The polymorphism varied from 86.84% to 100%, while the number of polymorphic alleles ranged from 1 to 4 with an average value of 2.63 per locus. The polymorphism information content (PIC) values ranged from 0.326 to 0.875 with an average value of 0.671, which shows their effectiveness in genetic analysis. Cluster analysis resulted in the distribution of salt tolerant and susceptible genotypes in separate groups which revealed the presence of inherent variations among mungbean cultivars. These variations were explored effectively for SSR markers studies. The developed SSR markers may help along with already available markers to execute further research on mungbean. The markers may be coupled with specific loci linked with salt tolerance. The developed markers will help to identify the QTLs (quantitative trait loci) or other important genes. These markers can also be utilized for testing the purity of hybrids or diversity assessment of Vigna species for important agronomic traits.

Black pepper is one of the most valued and widely used spices in the world and dominates multi-billion dollar global spices trade. India is amongst the major producers, consumers and exporters of black pepper. In spite of its commercial and cultural importance, black pepper has received meagre attention in terms of generation of genomic resources. Availability of markers distributed throughout the genome would facilitate and accelerate genetic studies, QTL identification, genetic enhancement and crop improvement in black pepper. In this perspective, the sequence information from the recently sequenced black pepper (Piper nigrum) genome has been used for identification and characterisation of Simple Sequence Repeats (SSRs). Total 69,126 SSRs were identified from assembled genomic sequence of P. nigrum. The SSR frequency was 158 per MB making it, one SSR for every 6.3 kb in the assembled genome. Among the different types of microsatellite repeat motifs, dinucleotides were the most abundant (48.6%), followed by trinucleotide (23.7%) and compound repeats (20.62%). A set of 85 SSRs were used for validation, of which 74 produced amplification products of expected size. Genetic diversity of 30 black pepper accessions using 50 SSRs revealed four distinct clusters. Further, the cross species transferability of the SSRs was checked in nine other Piper species. Out of 50 SSRs used, 19 and 31 SSRs were amplified in nine and seven species, respectively. Thus the identified SSRs may have application in other species of the genus Piper where genome sequence is not available yet. Present study reports the first NGS based genomic SSRs in black pepper and thus constitute a valuable resource for a whole fleet of applications in genetics and plant breeding studies such as genetic map construction, QTL identification, map-based gene cloning, marker-assisted selection and evolutionary studies in Piper nigrum and related species.