Genetic Analysis of Inheritance of Resistance in Some Hexaploid Wheat Cultivars to 134E134A+, 174E174A + Races of Stripe Rust

Inheritance of resistance to stripe rust was studied in wheat by determining the responses of 5 hexaploid wheat cultivars and 10 F1 progenies of their diallel mating crosses، against 2 races of pathogen including 174E174A+، 134E134 A+ in completely randomized design with 3 repetitions under greenhouse conditions at Tehran University. The components of resistance including latent period، infection type، pustule size and pustule density were recorded after inoculation over time. Analysis of variance showed significant differences among genotypes for all traits. Kotari cultivar had the most GCA among the parents for resistance increase. For the 2 races،there was dominance effect for most allels. In addition for both races the additive component compared to the non-additive component was more estimated to be more important to decrease infection type. Whereas the non-additive component was calculated to have more impact to increase size and density of pustules. The results of variance analysis of Vr+Wr and wr-Vr showed the existence of dominant effect for for the 2 races. Combined analysis of variance also indicated significant effects for race and race*genotype interactions for all traits suggesting that there differences in pathogenicity of races as well as the presence of specific genes in some of the cultivars.