Influence of plant population on water consumption and yield of confectionary sunflower varieties Karavan and Belochka

In 2022, research was conducted on the experimental field on the leached chernozem of the Western Ciscaucasia to study the influence of plant density (20, 25, 30, 35, 40 thousand pcs/ha) on water consumption and yield of largeseeded sunflower varieties bred at V.S. Pustovoit AllRussian Research Institute of Oil Crops (Karavan and Belochka). Weather conditions in the presowing spring period (March – April) were characterized by sufficient soil moisture and a favorable average daily air temperature of 13.4 °C. During the growing season (April – August), 363.9 mm of precipitation fell, which is 103.9 mm more than the norm. Abundant precipitation was observed in June during the head formation stage. The air temperature during the flowering – seed filling period exceeded the climatic norm by 1.8 °C. The highest water consumption of confectionary sunflower varieties in the 0–100 cm layer was observed at the plant population of 40 thousand pcs/ha and amounted to 80.0 and 78.3 mm. The highest yield of the variety Karavan (3.73 t/ha) was observed at the plant population of 30 thousand pcs/ha, and of the variety Belochka (3.25 t/ha) – at the plant density of 35 and 40 thousand pcs/ha.