Assessment of Genetic Diversity and Character Associations for Yield and Its Traits in Bread Wheat (Triticum aestivum L.)

Abstract

Background: Wheat (Triticum aestivum L.) an important self-pollinated and hexaploid (2n = 6x = 42) cereal crop belongs to the grass family Gramineae (Poaceae). With the gradual increase in human population, there is a substantial increase in the demands for food requirements. Hence, increasing the wheat production is an important goal to overcome the demand of food. The only alternative is to increase productivity by better crop management techniques and introduction of high yielding varieties. The current study aimed to study the genetic diversity in wheat genotypes for further selection and utilization in breeding programmes and identification of transgressive segregants for genetic improvement in wheat crop. Methods: In the field investigation during 2017-2019, forty genotypes were evaluated at research farm of Department of Genetics and Plant Breeding, Kisan P.G. College, Simbhaoli, Hapur (U.P). The observations were recorded on five randomly selected competitive plants from each genotype in each replication and recorded data from each replication was subjected to statistical analysis. Result: Significant differences were observed for all the characters studied in both environments (early and late). Highest GCV and PCV were recorded for flag leaf area, number of tillers per plant and grain yield in both environments. Plant height, days to 50% heading and grain yield in early sowing and for plant height, gluten content and grain yield exhibited high heritability estimates in late sowing. Biological yield and harvest index showed positive and significant association with grain yield under both environments. Biological yield and harvest index have positive and direct effect on grain yield in both environments. Forty genotypes were grouped into seven clusters in early sowing and six clusters in late sowing. Maximum inter cluster distance was observed between clusters VI and IV in early sowing and between cluster III and II in Late sowing. Genotypes PBW-34 showed wide genetic diversity in both the environments (early and late sowing). Based on the divergence studies it is suggested that maximum heterosis and good recombinants could be obtained in crosses between the genotypes of clusters which showed highest inter cluster distance and these genotypes can be utilized in crop improvement programmes.