SCREENING OF COLLECTION SAMPLES OF OATS BY RESISTANCE TO DAMAGE OF A DUST SMUT IN THE CONDITIONS OF THE MIDDLE VOLGA
Studies to identify the sources of resistance to dust smut among the collection samples of oats of various ecological and geographical origin, and varieties and breeding lines created in Ulyanovsk Research Institute of Agriculture, were performed on an artificial infectious background of Ulyanovsk Research Institute of Agriculture in the Middle Volga region in 2016-2018. 36 samples were studied that showed varying degrees of resistance-susceptibility to the harmful pathogen, including five varieties with identified resistance genes to diseases caused by smut fungi Ustilago avenae (Pers.) Rostr. and Ustilago kolleri Wille. Allur variety susceptible to dust smut was used as a universal indicator. The indicator variety over the years of research on average was affected by-44.4 %, with the lowest value in 2018 - 25.6 % and the maximum in 2017-58.1 %, when the conditions for the development of the disease were the best. Most of the oat samples studied showed varying degrees of resistance to Ulyanovsk dust smut population: 9 samples were immune, 14 were practically resistant. A significant proportion of stable genotypes were collected samples whose country of origin is the United States (52.2 %) and varieties of local selection (12.7 %). Of particular interest are the stable naked forms of oats, including the new variety of oat Griva. It has shown a high degree of stability over all the years of testing. Weak and medium susceptibility was characterized by 8 and 3 samples, respectively. Severe dust smut damage, over 50 %, was observed in two samples