Sunflower productivity depending on mineral nutrition and presowing seed treatment in the conditions of insufficient moisture

Abstract

The effect of the plant growth regulator (PGR) on growth, development and formation of the sunflower crop with different norms of mineral fertilizer under conditions of insufficient moistening of the Southern Steppe of Ukraine was studied. It was established that presowing AKM treatment of sunflower seeds of Perseus hybrid increases leaf area by an average of 18,8 %; increases the resistance of sunflower plants to abiotic stresses and increases yield by an average of 27,7 %. Improving the conditions of sunflower nutrition when using the norms of mineral fertilizers recommended and calculated from the point of zero balance of nutrient elements, provides an increase in the main indicators of plant growth and development, and sunflower yield. It is established that the share of PGR influence reaches 11,2 %, and that of mineral fertilizers – 8,6 %, with the share of influence of hydrothermal conditions of the year – 51,5 %.