Productivity of sunflower hybrids in Kursk and Krasnodar regions depending on the seed sowing rates and mineral fertilizers application

Influence of seed sowing rate and in-sowing fertilization (N30P30K30) on yield, oil content and yield of sunflower hybrids of the different maturity groups were studied on leached chernozems in the Kursk and Krasnodar regions in 2014-2016. The planting rate provided a plant population 40, 60 and 80 thousand plant per ha. The released hybrids of Limagrain Company (early LG 5400 XO, middle-early Goldsun and LG 5580, middle LG 5662) were used as objects of the research. Fertilizer was the compound NPK fertilizer, mark 15 : 15 : 15, an applied doze - N30Р30K30, control was planting without fertilization. The total plot area - 168 sq. m, accounted one - 84 sq. m. the cultivation technology was recommended for regions. The harvest was processed to the standard (100%) moisture and 100% purity. Oil content in seeds was determined on NMR-analyzer AMV-1006M. The results of records were treated by the methods of mathematics statistics. The application of in-sowing fertilizer appeared to be effective only in conditions of the Kursk region (oil content in seeds increased on 0.9%). And in the Krasnodar region this method did not cause a positive reaction in the studied genotypes. Seed sowing rates of 60 and 80 thousand seeds per ha provided equally high sunflower productivity compared to a rate of 40 thousand seeds per ha in Krasnodar region, otherwise, the sunflower productivity in the conditions of Kursk region depended a little of the changing in this factor, but there was observed a tendency in increase of yield, oil content and yield at seed sowing rates 60 and 80 thousand per ha compared to 40 thousand per ha. Thus, the maximal realization of a productivity potential in the new sunflower hybrids by Limagrain company on leached chernozems in the different environmental and climate conditions is guaranteed at seed sowing rates 60 and 80 thousand per ha, without applying of fertilizers or combine with local application of N30Р30K30 on soils less supplied with nutrients.