ELEMENTS COMPOSING THE YIELD OF SPRING WHEAT OF THE YOLDYZ VARIETY, DEPENDING ON THE DEFEAT OF ROOT ROT IN THE CONDITIONS OF THE PRE-KAMA REGION OF THE REPUBLIC OF TATARSTAN

The research was carried out to study the effect of the infestation of spring wheat plants of the Yoldyz variety by root rot on individual elements of the crop structure. During 2018-2019, experiments were conducted at the experimental field of the Kazan State Agrarian University on the basis of the Agrobiotechnopark, laboratory analyses were conducted at the Center for agroecological Research of the Institute of Agrobiotechnologies and Land Use. Experiments have shown that the survival rate of spring wheat plants in growing conditions was the lower, the higher the degree of their root rot disease. In the germination phase, 13.2-15.6% of plants were affected, and by wax ripeness, the lesion increased by 9.3-19.1%. Against the background of mineral nutrition N123P73K108, the lesion was 11.2% lower than against the background without fertilizers. With an increase in the degree of the disease, the ear of the ear decreases. In healthy plants, the number of grains in the ear was 21.4-25.3 pieces, and in severely affected plants – 8.0-13.4 pieces. Grain yield losses from root rot amounted to 0.54-0.69 t/ha. On the fertilized background of nutrition, losses were less by 0.15 tons per 1 ha, which is undoubtedly due to an increase in the resistance of spring wheat plants to root rot. The potential of spring wheat of the Yoldyz variety was realized through three main elements of the crop structure: a productive stem per unit area, the ear of the ear and the mass of 1000 grains. The effect of root rot on the elements of the structure of the spring wheat crop depends on the degree of root rot damage. The disease reduces the productive stem, the ear of the ear and the mass of 1000 grains more significantly with a 3-point lesion. Reducing the degree of damage to the root rot of spring wheat under conditions of application of calculated doses of fertilizers contributes to improving the elements of the crop structure and obtaining a high yield of grain of this crop.