CREATION OF HIGHLY PRODUCTIVE FORMS OF WINTER WHEAT WITH COMPLEX RESISTANCE AGAINST DISEASES AND PESTS ON ARTIFICIAL INFECTIOUS BACKGROUNDS OF THEIR CAUSATIVE AGENTS

Diseases of field crops substantially reduce the yield and quality of the obtained agricultural products. Underselection of gross grain harvest due to diseases and pests can reach about 25-30% annually. This necessitates the creation of resistant varieties for winter wheat selection. The purpose of this study was to create a new highly productive selection material with complex resistance against the main most harmful diseases for further use in the selection of winter wheat. In the phase of emergence of plants in the tube, winter wheat plants were infected with spores of the causative agent of brown rust according to E.E. Heschele’s method. To create an artificial infectious background of brown rust, a synthetic population of the pathogen (Institute of Plant Protection of the National Academy of Agrarian Sciences) was used as a reservoir of infection – a susceptible variety of Myronivska 10. To create an artificial infectious background of powdery mildew, a local population and an infectious reservoir of the American variety Keprock were used. In the F3 hybrid nursery against the provoking background of powdery mildew, combinations highly resistant to the pathogen (up to 5%) were selected, created with sources of resistance: Zdar, Fakon, Pi170911, Bongo – Svitanok Myronivskyi/Zdar, Kolos Myronivshchyny/Fakon, Berehynia Myronivska/Pi170911, Dostatok/Bongo. Resistance against the pathogen (up to 10.0%) was observed in two crossing combinations (Gorlytsia Myronivska/Gloria and Remeslivna/Wervok). Crossing combinations created with sources of resistance were selected on the artificial infectious background of hybrids of the fourth generation for resistance to brown rust: Flex, V 1275, Tobarzo, 203-238. It is worth noting the hybrids: Oberih Myronivskyi/Flex, Smuhlianka/V 1275, Monotyp/Tobarzo, Kolos Myronivshchyna/203-238. The largest number of grains in an ear was obtained from the combination Svitanok Myronivskyi/Zdar (61.5 pieces), and the largest weight of grain from an ear was obtained from the combinations Horlytsia Myronivska/Gloria and Berehynia Myronivska/Pi170911 (2.38 g and 2.37 g, respectively). The Oberih Myronivskyi/Flex combination stood out for its resistance to brown rust and performance elements. The samples selected based on the results of the study are used as valuable raw material to create new winter wheat varieties resistant to diseases in the Forest Steppe of Ukraine