genetic analysis and genome wide association mapping of economic traits in cucumber cucumis melo and cucumis sativus l

Abstract

A research was conducted at University of Horticultural Sciences, Bagalkot during Kharif newline2019 and 2020 in 150 diverse germplasm of cucumber belonging to two different species newlineviz.,Cucumis melo (116) and Cucumis sativus (34) to study diversity, correlation population newlinestructure and marker trait association. Experiment was conducted using Augmented Block Design newlinewith 3 checks ( Bagalkot local, Swarna sheetal and Pusa Bharkha) The diverse genotypes were newlineevaluated for was used for 31 traits (18 quantitative and 13 qualitative traits) for both phenotyping newlineand genotyping using 47 SSR makers. newlineAnalysis of variance revealed significant variations for most of the quantitative traits except newlinenode number of first female flower, number of flowers male, number of flowers female, number of newlinenodes per vine and sex ratio exhibiting the existence of variability estimates indicated the existence newlineof variability in the population. High heritability with high or moderate GAM was observed for newlinemost of the traits in both the seasons, which provides ample scope for selection. High variation was newlinealso confirmed for fruit qualitative traits based on frequency distribution. Fruit yield per vine had newlinepositive and significant association with many yield attributing traits. In path analysis number of newlinefruits per vine, vine length, number of flowers male, fruit length, and fruit diameter exerted direct newlinepositive effect towards fruit yield per plant. Therefore these traits given importance for selection in newlinethe improvement of fruit yield per plant in cucumber. newlineDiversity analysis based on eighteen quantitative traits resulted in 8 distinct clusters in newlinekharif 2019 and 9 clusters in kharif 2020. Distribution of genotypes into clusters is independent of newlineits origin and species. Maximum contribution towards genetic divergence was from number of newlinefruits per plant (12.2 percent) in kharif 2019 and fruit yield per plant (16.50) in kharif 2020 newlineseason. Principal component analysis revealed that the maximum variance was contributed by PC 1 newlinewith 17.9 percent and 18.26