Genetic diversity in green gram accessions as revealed by STMS markers

Abstract

Molecular characterization of green gram (Vigna radiata (L.) Wilczek) germplasm is essential for scientific assessment of variability and diversity for its better utilization in breeding programs. In this study, 120 accessions of green gram were analysed for 27 Sequence Tagged Microsatellites (STMS) loci. For data analysis, accessions were grouped into Indian and exotic. DNA profiling of the 120 accessions yielded 42 STMS products. The proportion of polymorphic products was 55.56% in Indian accessions and 51.85% in exotic accessions. Average Jaccard's similarity coefficient among all pairs of comparisons was 0.695. In unweighted pair group method of arithmetic averages (UPGMA) dendrogram, 5 major clusters were identified. High similarities among the Indian and exotic accessions were found and this could be due to free movement of Indian germplasm to other countries through international institutes. Analysis of molecular variance (AMOVA) analysis indicated that sampling should be practiced more extensively within populations to capture maximum variation. The study highlighted the need to make more elaborate collections from India to capture the diversity existing in green gram and to go for genetic enhancement for widening of the genetic base of cultivated green gram using wild relatives.

Key words: Genetic diversity, green gram, Vigna radiata, STMS.