INFESTATION OF WINTER WHEAT WITH LEAF DISEASES IN THE FOREST-STEPPE OF THE SAMARA REGION

Protecting crops against diseases is of paramount importance. In order to achieve high crop yields, it is necessary to reduce the negative impact of pests, of which disease pathogens are the most important. On average, it is estimated that up to 20 % of grain is lost due to diseases. This article analyzes the damage of winter wheat varieties by leaf diseases, and assesses their resistance to this pathogen. The peculiarities of winter wheat susceptibility to leaf diseases in different phases of its development and the effect of the disease on crop productivity are highlighted. The most resistant varieties to leaf diseases are proposed for introduction into production. This is very relevant at present, when high yield losses from these diseases are observed. The aim of our research was to study and clarify the species composition of causative agents of winter wheat diseases affecting leaves, stems and ears in forest-steppe of Samara region. Studies on the subject were carried out in the experimental fields of the P.N. Konstantinov Volga Research Institute of Wheat Disease Control. Brown rust and powdery mildew infestation starts from the lower tier leaves. Resistance to brown rust was determined by the degree of damage to the flag leaf on the Peterson scale. The winter wheat varieties Povolzhskaya 86 and PovolzhskayaNiva were more resistant to leaf rust pathogens in the years of study, while Konstantinovskaya was less resistant. Despite the high percentage of disease prevalence, these varieties have high yields, indicating field resistance. The most common leaf diseases in 2021 were powdery mildew, brown rust, and septoriosis.