Bilyaeva I. The efficiency of winter bread wheat selection for resistancе to powdery mildew and leaf rust under different environments of growing

Object: the peculiarity of inheritance and variability of resistance and tolerance of bread winter wheat to powdery mildew and leaf rust agents under irrigated conditions and without watering. Aim: to update the principles of made out of winter wheat breeding material with genetic protect of resistance and tolerance to powdery mildew and leaf rust agents. Methods: breeding, visual analysis, weight, statistic. Novelty: fist it was ascertained that efficiency of individual selection for resistancе to the diseases considerably increased if it was made on the basis of the hybrid populations modified by mass selection under conditions of natural and artificial infection with the pathogens. Results: it was found that resistance to powdery mildew and leaf rust is controlled by one-two genes in a dominant or recessive state, and about 30 % of the investigated cross combinations were characterized by complementary interaction of two genes of resistance.It was revealed that when dominant genes controlled the resistance to the pathogen the level of moisture content did not influence on the ratio of R:S plants, but when it was under recessive genes control the ratio could change.The success in breeding for increase in resistance to powdery mildew and leaf rust can be achieved by mass and individual selection from the cross combinations in which the trait is controlled by one or two dominant genes (R:S = 3:1; 9:7). Selection for increase in resistance to pathogene was more effective on irrigated plots in comparison with non irrigated ones. It was proved that plant tolerance has not correlation with productivity; breeding for combination in the one phenotype this traits have not limits. Application stage: winter wheat variety Maria was entered in the State Register of Plant Varieties of Ukraine in 2008. It were patented two new methods. Application area: research establishments of UAAS