INFLUENCE OF MIXED FERTILIZERS ON RICE YIELD AND ITS STRUCTURAL ELEMENTS
Intensive rice varieties released for production are able to form yield up to 10-12 t/ha, but their potential is not implemented in full. For this, among other things, one must ensure complete and balanced mineral nutrition of plants. One of the ways to solve this problem is to to apply during main application mixed fertilizers containing not only phosphorus and potassium, but also nitrogen fertilizers. Under conditions of field experience we have studied effectiveness of mixed fertilizers of various compositions, methods of their application, determined their impact on the nitrogen status of nitrogen nutrition of plants (based on the results of leaves diagnostics), yield and the elements of its structure. The results of express control of nitrogen status of rice plants had shown that the largest supply of nitrogen was in the variants where all the nitrogen dose was applied during main application. This scheme of application provides the best conditions of nitrogen nutrition of plants in the first half of the growing season. Yield increase was provided by use of mixed fertilizers, which include those from 50 to 100% of the nitrogen fertilizer was introduced during main application (0,45-0,93 t /ha) due to the increase of productive tillering and grain weight per plant. The optimum composition of mixed fertilizers and their application technology were developed.