Vegetable peas (Pisum sativum L.) diversity: An analysis of available elite germplasm resources with relevance to crop improvement

Aim of study: To determine the amount of diversity in pea breeding materials with the objective to classify a set of potential parents carrying novel/economic variations that could be used in future breed pea varieties. Area of study: ICAR–Indian Institute of Vegetable Research, Varanasi. Material and methods: A total of 45 pea accessions were analysed for phenotypic and molecular diversity using 17 agro-morphological traits and 52 SSR markers. Main results: All traits under investigation showed considerable genetic variation. The genotypes exhibited 6.7, 2.7 and 12-fold variation for traits viz., pods/plant, 10-pod weight and yield/plant, respectively. Among 52 SSR markers, 22 were found to be polymorphic. A total of 90 allelic variants were detected, with an average of 2.7 alleles/locus. PIC and D-values for markers AA135 (0.79 and 0.81) and PSMPSAD51 (0.7 and 0.74) were the highest, while AB40 (0.19 and 0.2) had the lowest. Two principal components PC1 and PC2 explained 46.96 and 23.96% of total variation, respectively. The clustering based on agro-morphological traits differentiated 45 individuals into three mega clusters, while SSR markers-based clustering classified these accessions into four groups. Research highlights: Based on their uniqueness, we identified a set of genotypes (VRPD-2, VRPD-3, PC-531, ‘Kashi Nandini’, ‘Kashi Udai’, ‘Kashi Mukti’, ‘Arkel’, VRPE-101, ‘Azad Pea-3’, EC865944, VRPM-901 and VRP-500) harbouring genes for various economic traits. The findings presented here will be extremely useful to breeders who are working on improvement of peas through selective introgression breeding.