Abstract

                                Yellow vein mosaic virus (YVMV) is the most destructive viral disease of okra,has become a limiting factor in the successful cultivation and production ofokra in India, resulting in yield losses ranging from 17.09 to 96.49 per cent.As a result, it is critical that breeders continue to develop superior varietiesor hybrids with long-lasting resistance to overcome this major devastatingdisease. In this context present investigation was carried with 74 elite okralines to discover potential parents for a resistance breeding programme.On the basis of D2 values the 74 genotypes were divided into seven groups.Cluster I constituted the highest number of genotypes followed by clusterII, III, IV, V, VI and VII. The traits per cent disease index of YVMV contributedmaximum towards divergence followed by total phenolic content, peroxidaseactivity, fruit yield per plant, number of primary branches and number offruit per plant. PCA showed four principal components with Eigen valuesmore than one viz., 3.87, 3.21, 1.89 and 1.64 and accounted 81.56 percent of the total genetic variation. Principal component analysis revealedthat PC1 captured potential traits viz., total phenolic content, peroxidaseactivity, polyphenol oxidase, number of fruits per plant, number of primarybranches per plant and fruit yield per plant, which could be used in futurebreeding programmes for high yield and YVMV resistance. The present studyit was revealed that, eleven accessions viz., AE-65, AE-66, AE-CBE-921,Pusa Bhendi-5, SB-2, IC112449, AE-CBE-94, AE-CBE-943, AE-CBE-934,AE-CBE-92 and AE-CBE-93 appeared to be very promising lines for futureuse in resistant breeding programmes.

Key words : Okra; YVMV; Genetic diversity; Cluster analysis; PCA