Ecology, Environment and Conservation Paper

GENETIC DIVERSITY STUDIES ON FRENCH BEAN GERMPLASM USING SEED MORPHOLOGICAL CHARACTERS

Chandramohan Sangh, Lalit Arya, Rakesh Bharadwaj and Veena Gupta

Abstract

The study of variations and their differentiation in common bean was based on seed morphological characteristics. The knowledge and understanding of the genetic structure of bean (Phaseolus vulgaris L.) is important for in-situ conservation. The purpose of this paper was to study the pattern of variation in seed morphological traits. Fifty genotypes were taken for this study consisting of both indigenous and exotic collections. Marked variations were observed with respect to colour, shape, size, seed coat thickness, coat pattern, hilum and hilum ring colour. Kidney shape was the predominant trait. For seed coat colour, brown pale to dark was the predominant trait, while the least was red, whitish and white purple tinge. For seed coat pattern, majority of them did not had any pattern but variation exist viz. Broad Striped, Constant mottled, Marginal colour pattern, Mottled, Rhomboid Spotted, Speckled, Striped and Circular mottling . Most of the accessions had shiny seeds. For colour of hilum, white colour was predominant and least was beige. For colour of hilum ring, brown colour was predominant and least was maroon and violet. Wide variability was also present for seed coat thickness seed length, seed width and test weight (100 seed weight). The seed coat thickness of French bean germplasm varied from 0.1033 mm to 0.215 mm. Test weight varied from 19.86 g-56.85 g. The range of seed length observed was 9.054 mm to 17.226 mm. The range of seed width 5.932 mm to 8.886 mm. Seed coat thickness was positively correlated with seed width. Test weight was also positively correlated seed length and seed width. Seed length was also positively correlated with seed width. Highest allele number was found for seed coat colour and lowest for brilliance of seed and hilum colour. Highest Nei’s index and Shannon weaver index was found for seed coat colour and lowest for brilliance of seed. Dendrogram was constructed based on dissimilarity matrix and grouped genotypes into 3 clusters. All the 3 clusters had mixture of both indigenous and exotic collection germplasm. Accessions with very similar or identical morphological characters were clearly distin-guished