Resistance of soft winter wheat varieties against pathogens of major leaf­stem diseases in the South of Ukraine

Purpose. To evaluate common winter wheat varieties of the Plant Breeding and Genetic Institute (PBGI) for resistance to brown and leaf rust and powdery mildew pathogens and to identify those with complex immunity to the above diseases that can be used as resistance donors in breeding practice. Methods. During 2021–2023, 35 wheat varieties of the PBGI (Wheat Breeding Department and Laboratory of Intensive Wheat Varieties) were studied. Methods of phytopathological assessment were used on separate and complex artificial infectious backgrounds of the studied diseases in the field and under artificial climatic conditions at the development stages of BBCH 12 and BBCH 59–69. Results. The varieties ‘Oktava’ and ‘Pozytsiia Odeska’ were resistant to brown rust in the juvenile and adult phases, and ‘Oktava’, ‘Vidpovid Odeska’ and ‘Pozytsiia Odeska’ were resistant to stem rust. Moderate resistance to powdery mildew was demonstrated by varieties ‘Oktava’, ‘Shchedrist’, ‘Zhytnytsia’, ‘Harantiia’, ‘Fortetsia’ and ‘Pozytsiia Odeska’ in the juvenile phase, and complex resistance to the disease group was demonstrated by ‘Oktava’ and ‘Pozytsiia Odeska’. Conclusions. The varieties with complex resistance to brown rust, leaf rust and powdery mildew justify the efforts made to develop them and are valuable for further breeding as they often do not require fungicides during cultivation.