Winter wheat ecological response to changes in the Donetsk ridge northern part environmental conditions

According to the research results of 1995-2019 there is a high variability of the yield of winter wheat in conditions of changes in the external environment - from 8.9 to 50.1 centners/ha. Over 25 years of research, there was a significant increase in atmospheric temperature - by 1.7 °С (21.5 %) and an increase in precipitation by 89.3 mm (21.3 %) in comparison with the long-term average values. To determine the magnitude of the combined effect of precipitation and air temperature on yield and calculate the theoretical values of yield, a model was built based on the multiple regression equation. There was a negative pairwise correlation between the dependent variable and air temperature in October, April, May and a positive correlation in November and March. The most significant relationship was established between the yield of winter wheat and precipitation in September: r ≥ 0.67 at p = 0.001. Over a period of 24 years, the yield of winter wheat most strongly depended on the lack of precipitation in September. The precipitation in September varies greatly from year to year: from 1 mm in 1998 to 142 mm in 2001, the coefficient of variation exceeds 79 %. Determination of the yield of winter wheat with precipitation and temperatures exceeds 75 %. The mutual influence of the monthly amount of precipitation and the average monthly air temperature has a limiting effect on the formation of the winter wheat yield in the steppe conditions of the northern part of the Donetsk Ridge. At the same time, there is a tendency towards a decrease in the yield of the test crop under conditions of changes in the external environment.