THE EFFECTIVENESS OF FUNGICIDES AND FOLIAR FERTILIZATION IN PROTECTING SPRING SOFT WHEAT IN THE SOUTH OF WESTERN SIBERIA

In years with favorable moisture in the south of Western Siberia, the loss of springwheat grain yield from leaf-stem infections increases sharply to 30% or more. The use of fungicides in combination with foliar feeding allows not only to preserve the crop, but also to improve its quality indicators. The studies were conducted in 2018-2021. The soil of the experimental plot is chernozem-meadow, heavy loamy. Four-field grain-fallow crop rotation, predecessor – wheat after fallow. Two-factor field experiment, plot area 25 m2, four-fold repetition. The purpose of the work is to assess the biological effectiveness of tank mixtures of fungicides with urea and liquid complex fertilizer (LCF) on the yield and quality of spring wheat grain. The average infestation of crops by powdery mildew over 4 years is 21,8%, maximum in 2018 – 30,5, rust species in 2019 – 68, average – 52,4, in the dry year 2021 – 1.0%. The incidence of septoria is insignificant, with a maximum of 8,6% in 2019. Treatment of crops with complex fertilizer reduced the development of powdery mildew to 32, types of rust to 61,6, septoria to 28,8%, and to a lesser extent when working with urea. On average, the biological effectiveness of the variants with Abacus Ultra, a fungicide based on triazole and strobilurin, was higher and ranged from 52,5 to 99,8%, and the drug Title Trio based on triazoles was lower, from 45,7 to 97,3%. Tank mixtures of fungicides and fertilizers did not reduce their effectiveness against spring wheat diseases. Fertilizing with liquid complex fertilizer provided the most stable and significant increase in grain yield over the research period – 0,63, urea 10 kg/ha – 0,46, 15 kg/ha – 0,40 t/ha. The greatest increase – 1,21 t/ha – was provided by a tank mixture with Abacus Ultra + liquid and liquid fertilizers, and economic efficiency, respectively, was 23,8-37,5%. A fungicide containing strobilurin (pyraclostrobin) has been shown to be highly effective in increasing the quality parameters of wheat grain.