PRODUCTIVITY FORMATION OF SUNFLOWER HYBRIDS BY DIFFERENT NUTRITION CONDITIONS

In the article presented results of research, aimed at studying the influence of various nutritional conditions on formation of productivity elements of sunflower hybrids. The purpose of research was to study effects of different variants of the basal fertilization and top-dressing on its background on sunflower productivity formation on podzolic black soil. Application of mineral fertilizers had a significant effect on flower head formation. Application of fertilizers as basal fertilization provided an increase in plant head diameter among the plants of studied sunflower hybrids on 15.5-19.0%. In variants with foliar application of complex fertilizer "Yarylo" oily on the background of basal mineral fertilizers application was observed the increase of indexes by 0.5-0.9 cm, depending on basal fertilization rate. The one thousand kernel weight, formed by the hybrids in the trial, varied from 58.9 to 72.7 g. The highest weight of one thousand kernels was formed by plants of hybrid Golden, regardless of fertilizing options. The best results were obtained in the variant with basal fertilizer application N₈₀P₈₀K₁₂₀ and top- dressing with complex microfertilizer "Yarilo" oily at the stage of 3-4 true leaves and head formation. The hull content in kernels of investigated hybrids determined by their genetic characteristics. On the check variant, this parameter was maximal for each hybrid and made up: 23.1% for the hybrid Tulsa, 22.7% in the hybrid Pronto, and 22.4% in the hybrid Golden. Application of fertilizers as basal and top-dressing fertilization allowed to reduce this parameter. The kernel yield in the field trials, depending on studied factors, varied from 1.54 to 3.11 t/ha. The highest yield in the trials was formed by the hybrid of sunflower Golden