Seeds yield and oil content of the maternal forms of sunflower hybrids depending the plant population

We studied formation of seed yield and oil content using maternal forms of sunflower hybrids (VK 101, VK 678, VK 905, VA 760, ED 765) bred in the All-Russian Research Institute of Oil Crops by Pustovoit V.S. on leached chernozem in 2017-2018. The results showed increase of plant population of the maternal forms of sunflower hybrids from 40,000 to 50,000 60,000 plants per ha causes seed yield increase in average by 0.12-0.16 t per ha (9.6-12.8%), and then seeds yield is decreased by 0.04 t per ha when plant population is increased from 60,000 to 70,000 plants per ha. But oil content in seeds was increased at plant population 70,000 plants per ha by 1.7% - from 72.3 to 44.0%, compared to plant population 40,000 plants per ha.