Формирование продуктивности материнских линий гибридов подсолнечника при выращивании с разной густотой стояния растений

Abstract

In 2017–2020, we studied the yield formation, its structure and quality in early-maturing self-pollinated lines – maternal forms of sunflower hybrids VK 101, VK 678, VK 905, VA 760, and ED 765 bred at V.S. Pustovoit All-Russian Research Institute of Oil Crops. The research was carried out on leached chernozem in the central natural and climatic zone of the Kras-nodar region under free flowering cultivation with plant population of 40, 50, 60, and 70 thousand plants/ha. We established the negative dependence of seed yield from the sieve with oblong holes of 2.5 × 20 mm in size on increasing the plant density. The maximum yield of this seed fraction was obtained when growing maternal lines VK 101 and ED 765 with a population of 50 thousand plants/ha (1.18 and 1.12 t/ha), VA 760 and VK 678 – 60 thousand plants/ha (1.16 and 1.33 t/ha), VK 905 – 70 thousand plants/ha (1.50 t/ha). With the thickening of sowings of maternal lines by 10 thousand plants/ha, the yield of seeds from the sieve with a hole size of 2.5 × 20 mm on average decrease in VK 905 by 1.9%, VK 101, VK 678, and VA 760 – by 4.9–5.0%, and ED 765 – by 5.9%. With increasing the plant population from 40 to 70 thousand plants/ha, the oil content of seeds increased from 0.6% for VK 101 to 3.0% for VK 678, and on average for the maternal lines of hybrids – by 1.7%. We established the negative dependence of the head diameter, size of productive area of a head, thousand-seed weight, and num-ber of filled seeds in a head on increase in the plant density. The increase of plant population by 10 thou-sand plants/ha resulted in decrease of a head diameter by 0.64–1.02 cm, productive area of a head by 14.4–27.2 cm2, thousand-seed weight by 1.4–3.5 g, a number of filled seeds in a head by 37–125 seeds, depending on the maternal line of a hybrid.