LAUSR

Abstract Field studies conducted in 2018–2019 in the northern Steppe of Ukraine with sunflower hybrids of different maturity groups (LG 50300, LG 5580, LG 5478, LG 5638, LG 5662) showed that the crop density of early-crop hybrid LG 50300 from 55,000 plants/hectare to 70,000 plants/hectare led to a decrease in productivity by 0.11 t ha−1 and a decrease in oil content by 0.9%. The density of middle-early hybrid LG 5580 resulted in a decrease in sowing productivity of 0.21 t ha−1, while oil content remained nearly the same. Another middle-early hybrid LG 5478 showed slight variations in productivity and oil content with an increase of crop density. The study of the mid-season hybrid LG 5038 showed a decrease in sowing productivity by 0.2 t ha−1 with the density up to 70,000 plants/hectare. Mid-season hybrid LG 5662 with density of 70,000 plants/hectare showed productivity increase by 0.14 t ha−1.