Estimation of Genetic Parameters for some Agronomic Traits, and Resistance to Stripe and Stem Rusts using Six Parameters Model in Three Bread Wheat Crosses

Abstract

The present investigation was carried out during seasons 2015/2016, 2016/2017 and 2017/2018 at the Experimental Farm of Sakha Agricultural Research Station, to determine type of gene action and some genetic parameters, also study the resistance of stripe and stem rust diseases in three bread wheat crosses )line 1×sids1), (line 1×line 2) and (line 1×misr 3) derived from four parental wheat genotypes. Genetic material included six populations (P1, P2, F1, F2, BC1 and BC2) for each cross. The studied characters were resistance to stripe and stem rust diseases, plant height)cm), number of spikes/plant, number of kernels /spike, 100 - kernel weight (g)and grain yield / plant (g). Results in general indicated that negative heterotic effects relative to the mid- parent and better parent were found for most of the agronomic traits and most crosses of stripe and stem rust traits. Non-allelic interaction was found for all studied traits in all the crosses under study. Dominance gene effects were larger in magnitude than the additive gene affects for most studied traits. The estimates of heritability in broad sense were high in most studied crosses. Narrow sense heritability estimates were low to relatively high for all the studied crosses. Generally, the best crosses were the third cross (Line1 × misr3) and the first cross (Line1 × Sids 1) for resistance to stripe and stem rust diseases, respectively, and could be recommended to be used in the wheat breeding program.