The effect of hydrothermal conditions on the yield of spring soft wheat (Triticum aestivum L.) when using mineral fertilizers in the arid Volga region

The paper reflects the results of the effectiveness of the use of various doses of mineral fertilizers in a long stationary experiment on spring soft wheat for nine rotations of a six-field crop rotation (27 years of cultivation) in the conditions of the steppe zone of the Volga region. The systematic use of medium and high doses of nitrogen-phosphorus fertilizers contributed to obtaining the highest yield increases to control in the experiment throughout the entire research period. The average level of correlation between hydrothermal conditions in the period May-July and crop productivity has been established. Separate calculations by month showed an average level of correlation with June. Based on the results of regression analysis, the degree of influence of hydrothermal conditions as a factorial feature on the productivity of spring soft wheat in the experiment was determined. The analysis showed that the effect of the obtained values of the hydrothermal coefficient in May and July on the production process of vegetating plants was insignificant, and in June it reached 30% according to experience.