Resistance of spring wheat cultivars to pathogens of leaf diseases and root rot in the Right-bank Forest Steppe of Ukraine

Abstract

Goal. Determine the degree of resistance of spring wheat cultivars to pathogens and root rot in the Right-bank Forest Steppe of Ukraine and identify promising sources of resistance. Methods. Laboratory — selection of infection material with different levels of virulence, development of infection material of leaf rust and septoria of wheat; field — creation of artificial infection and provocative backgrounds of pathogens and assessment of resistance of the collection of cultivars to this phytopathogens; analytical in mathematical — analysis of the obtained data, calculation of the intensity of disease development. Results. In 2017—2019, 30 cultivars of spring wheat from the collections of the National Center for Plant Genetic Resources of Ukraine were provided by the Ustimovskaya Plant Research Station of the Institute of Plant Growing. V.Ya. Yuriev NAAS was evaluated for resistance to the main leaf pathogens: powdery mildew Blumeria graminis (DC.) E.O. Speer f. sp. tritici Em. Marchal, brown rust Puccinia recondita f. sp. tritici Rob. et Desm. (syn. Puccinia triticina), leaf septoria Zymoseptoria tritici Rob. et Desm., pyrenophora Pyrenophora tritici-repentis (Died.) Drechsler and root rot. The collection included cultivars of Ukrainian, Russian, Kazakh and Kyrgyz breeding. Assessment of resistance to powdery mildew, pyrenophora and root rot was performed on a natural infectious background, and the pathogens of septoria and leaf rust on the created artificial complex infectious background during the period of maximum disease development. Cultivars were characterized by their degree of stability using a 9 — point immunological scale. According to the research results, the degree of resistance of varieties of Ukrainian and foreign breeding to pathogens of leaf diseases and root rot was established. Among the studied spring wheat collection, a number of cultivars were identified that showed resistance both to individual pathogens and to a group of diseases in the Right-Bank Forest Steppe of Ukraine: to powdery mildew — 4, brown rust — 20, septoria — 8, pyrenophorosis — 8, roots — 7. The group resistance was characterized by 13 spring wheat cultivars. Conclusions. Valuable sources of resistance are cultivars of Oksamit Mironovsky (UKR) and Lebedushka (RUS) with resistance to the group of pathogens of powdery mildew, leaf rust and pyrenophorosis, characteristic of the Right-Bank Forest Steppe zone of Ukraine. Other spring wheat cultivars that have high resistance to both individual pathogens and their groups are recommended to be involved in the breeding process to create new promising spring wheat cultivars with high resistance rates.