Studies on genetic diversity of French bean (Phaseolus vulgaris L.) landraces of Himachal Pradesh based on morphological traits and molecular markers

Abstract

The knowledge of the extent of underlying diversity in the germplasm can be effectively employed to breed desirable cultivars and to challenge the consequences of the unprecedented biological, physical and chemical stresses of the future growing conditions. In the present study, total 26 geographically diverse French bean genotypes collected from different agro-climatic zones of Himachal Pradesh and two check varieties viz., Baspa and Jawala were grown under randomized complete block design with three replications for deciphering the extent of genetic diversity. The extent of variability was assessed using DUS morphological traits and PCR based approach. Analysis of variance for quantitative traits showed significant differences among all the genotypes for all the characters studied. The genotypes RL-19 and RL-20 gave higher seed yield and performed better for many of the horticultural traits over all the checks. Further, 15 RAPD primers were used for scoring polymorphism at the DNA level. The French bean landraces produced 79 PCR fragments, of which 59 were polymorphic with an average of 3.93 polymorphic fragments per primer. The overall percentage of polymorphism was recorded 74.62 per cent. The average Jaccard similarity index among genotypes ranged from 0.48 to 0.98, thereby showing sufficient genetic variability. Geographical affiliations and morphological associations were observed while studying the genotypic patterns within each group i.e. A, B, C and D. Such variability is desirable in breeding programs. Which also reveal the inherent capacity of the community as a selector, conservator and improver of the potential genetic resource for sustainable future.