Inheritance Studies for Leaf Rust Resistance and Different Economic Traits in F2 Generation Developed Through Introgression of Functional Genes in Bread Wheat Genotypes

Abstract

Wheat rusts are potential threat for sustainable wheat production in different parts of the global village. Among these, leaf rust caused by Puccinia recondita is one of the most important leaf rust diseases. During the year 2012-13, an experiment was conducted at experimental farm of NIA, Tandojam, which comprised of seven wheat genotypes; four leaf rust resistant (Sunco, Vasco, SD-222 and SD-333) and three susceptible (TD-l, ICARDA and SD-888) were used to develop four F2 cross combinations (TD-1 x Vasco, ICARDA x SD-222, TD-1 x Sunco and SD-888 x SD-333) in order to study the genetic pattern of resistance genes. The observations were recorded on gain yield plant-1 and its associated traits to evaluate genetic potential of the F2 populations. The analysis of variance revealed significant differences among F2 populations for majority of the traits studied which suggested that the breeding material is worth for selection of desirable plants from subsequent segregating generations. Based on mean performance, among the parental lines, the parent SD-888 exhibited outstanding performance for spike length and grains spike-1 ; however, the variety TD-1 ranked second which showed better performance for 1000 grain weight and grain yield plant-1 . Considering the F2 hybrids, the progeny TD-1 x Vasco gave desirable results for 1000 grain weight, grain yield plant-1 , whereas cross combination SD-888 x SD-333 also produced interesting results for spike length, spikelets spike-1 and grains spike-1 . On an average, F2 progenies gave higher values for most of the traits which could be either due heterotic effects or transgressive segregants developed through recombination of genes. With regards to heritability percentage in broad sense, the F2 progeny ICARDA x SD-222 expressed high heritability for spike length and grains spike-1 . Similarly, the F2 cross combination SD-888 x SD-333 also showed high heritability for 1000 grain weight and grain yield