Analysis of Trait Association and Genetic Diversity in Garden Pea ( Pisum sativum L.) Genotypes under Middle Gangetic Plain Region of India

Background: Garden pea is a cool season vegetable crop cultivated extensively throughout the world. Besides nutritional quality it also boosts soils through the fixation of atmospheric nitrogen. The most important task of pea breeding is to develop varieties with high and stable production, different maturity types and resistance against biotic and abiotic stresses. To fulfil these objectives, analysis of genetic diversity is the prerequisite to choose genetically diverse parents for a successful hybridization program and to know the source of genes for a particular trait within the available germplasm. Methods: A study was conducted at ICAR-Indian Institute of Vegetable Research (IIVR), Varanasi during 2015, using principle component analysis, correlation analysis and stepwise regression analysis approaches to assess the genetic diversity present in 160 pea genotypes for the identification of diverse parents for use in crop improvement. Result: Based on the phenotypic data, three superior genotypes VRPD-2, VRPR-15 and VRP-292 were identified on the basis of pod yield, number of pods per plant, ten pod weight, pod length and number of seeds per pod whereas three other genotypes VRPE-45-1, VRPE-55 and VRPE-36 were found early flowering. Principle Component Analysis revealed that first four principle components contributed to 85% of the total variation so these four were given due importance for further explanation. Stepwise multiple regression analysis revealed that number of pods per plant, ten pod weight and number of internode for first pod were the best predictors of pod yield per plant.