Abstract:
The scientific paper presents the experimental data on the impact of different cultivation technologies on the indexes of assimilation surface area, chlorophyll content, its fractional composition (fractions “А” and “В”) and the yields of sunflower hybrids under conditions of the Southern Ukrainian Steppe. The research was conducted in 2018-2019 on dark-chestnut soil in the semi-arid conditions. The research scheme consisted of the following factors and their variants: sunflower hybrids (PR64F66, Tunca); cultivation technologies (intensive; organic). The research results proved that the best conditions for the formation of the largest area of assimilation apparatus by sunflower plants were created in the organic technology (treatment of soil + seeds + plants with organic preparations during the growing season) when growing the hybrid Tunca: at the stage of 3 pairs of true leaves - 2.9; the formation of heads - 27.1; flowering - 37.1 and milky ripeness - 29.0 thousand m2/ha. Under the same conditions there was maximum amount of hlorophyll (9.71 mg per 1 g of dry weight) and enzymes. Sunflower cultivation under the organic technology caused the formation of maximum yield (PR64F66 F1 - 2.42 and Tunca F1 - 2.41 t/ha), realization of biological productivity (90.9 and 90.7%) and fat content (48.7 and 49.8%).
