Fertilizers influence in grain row-crop rotation on leached chernozem fertility and sunflower productivity

Influence of 16-years fertilizers usage in grain row-crop rotation of oil crops on agrochemical, physico-chemical, microbiological traits of leached chernozem fertility and sunflower productivity was studied on example of field experiment. Changes m content of humus, nitrogen, phosphorus, potassium, exchange bases, acidity, microbiological activity of soil under influence of applied fertilizers have been shown. Information on sunflower water consumption; content and total assimilation of nitrogen, phosphorus, potassium and these elements consumption for the formation of 1 ton of seeds; seeds, oil and protein productivity have been shown as well. It was proved, that during systemic fertilizers application in rotation (in average N 40-80P 40-90К 4-60) sunflower slightly reacted to fertilizers application, but used their residual effect. When cultivated layer of soil contains 24.0 mg of mobile phosphates and 27.0 mg of exchange potassium per 100 g of soil and more, it is to no purpose to apply fertilizers in autumn tillage. Such level of effective fertility allows achieving up to 75-80 % of potential sunflower seeds productivity.