Reaction of sunflower hybrids on seed sowing rates and fertilizers application in the different soil and climatic conditions

Influence of seed sowing rates on sunflower hybrids seeds and oil yield, oil content was studied at application of mineral fertilizers in the different soil and climatic conditions of the Russian Federation (Kursk and Krasnodar regions) in 2014-2015. There were used the seed sowing rates provided plant population 40, 60 and 80 ths plants per ha. The released hybrids of the different maturity group, for classic cultivation technology of Limagrain Co. were used in research: early hybrid LG 5400 ХО, middle-early hybrids Goldsun and LG 5580, and middle hybrid LG 5662. A compound NPK fertilizer was applied in doze N30P30K30. The total sowing plot area was 168 sq. m, accounting area - 84 sq. m. Cultivation technology was common for the region of production, excluding studied methods. The yield was processed to the standard humidity (10%) and 100% purity. Oil content of seeds was determined on NMR-analyzer AMV-1006M. The results of observations were worked out by methods of mathematical statistics. Effect of N30P30K30 application at sowing on leach chernozem was proved by increase of yield on 0.16 t per ha, oil content - on 0.9% in 2014, and 0.07 t per ha and 0.2%, respectively, in 2015 in conditions of Krasnodar region. In conditions of Kursk region, fertilizer application did not promote significant increase of yield of studied hybrids in 2014, excluding hybrid LG 5400 XO at seed sowing rates 60 and 80 ths seeds per ha. It showed yield increased on 0.39 and 0.24 t per ha and oil content of seeds - on 1.8 and 2.3%, respectively, in 2014. In 2015, this agrotechnological method provided yield increase on 0.18 t per ha and oil content decrease on 1.5% due to the weather conditions of a year. The researches showed that the seed sowing rates 60 and 80 ths seeds per ha provided equally high productivity of sowing plots of sunflower hybrids of the different maturity groups.