THE INFLUENCE OF SOWING RATES ON THE FORMATION OF PRODUCTIVITY INDICATORS OF WINTER WHEAT KINDS LUTESCENS AND ERYTHROSPERMUM IN THE CONDITIONS OF THE NORTHERN STEPPE OF UKRAINE

Abstract

Purpose. To establish the effect of sowing norms of winter wheat of different kinds on the adaptation of plants to the droughty conditions of the Steppe and the formation of grain yield. Methods. Field, laboratory, mathematical and statistical. Results. The research was carried out at the experimental field of the Donetsk SARS of the National Academy of Agricultural Sciences in 2020–2022. The new winter soft wheat varieties Vezha (Lutescens) ta Yuzovska (Erythrospermum) were used for sowing. The predecessor is a black pair. The seeding rate of 4,5 million was chosen as the standard. It was established that different sowing rates had different effects on winter wheat plants depending on the varieties during the growing season. The highest coefficients of general tillering in the Vezha variety were at the lowest sowing rates – 1,5 and 2,0 million units/ha. In the Yuzovska variety, the highest coefficient of tillering was at the sowing rate of 3,5 million units/ha. The number of productive stems, regardless of the variety, decreased proportionally from the lowest norm to the highest. Plants of the Erythrospermum kind were more resistant to sowing thickening, in contrast to Lutescens plants, which formed the highest coefficients of general tillering at the sowing rates of 3,0–4,0 million units/ha. When comparing different varieties according to the parameters of the crop structure, it was found that the length of the spike in plants of the kind Erythrospermum did not change significantly depending on the rate of sowing, while the length of the spike of plants of the kind Lutescens decreased with an increase in the rate of sowing. With an increase in the seeding rate, Lutescens plants significantly increased the rate of 1000 grains from 38,6 g at a seeding rate of 1,5 million pieces/ha to 45,5 g at a seeding rate of 7,0 million pieces/ ha. In plants of the Erythrospermum kind, this indicator changed less significantly. The highest level of productivity of the Vezha variety of Lutescens winter soft wheat was provided by the sowing rates of 4,0 million units/ha (7,3 t/ha) and 2,5 million units/ha (7,2 t/ha), at seeding rates of 3,0, 3,5, and 5,0 million units/ha, the grain yield was on par with the control variant, with an increase in the seeding rate, a significant decrease in yield. An increase in the yield level of soft winter wheat of the Yuzovska variety of Erythrospermum was noted from the lowest norm (1,5 million units/ha) to 4,0 million units/ha, respectively from 6,3 t/ha to 7,1 t /Ha. With an increase in the rate of sowing, the yield decreased significantly. Conclusions. When comparing the two kinds, the same regularity can be observed regarding the influence of the seeding rate on plant productivity in the conditions of the Northern Steppe of Ukraine, but plants of the Erythrospermum kind differed by a smaller fluctuation of this indicator depending on the seeding rate. The highest level of productivity of plants of the Lutescens kind was provided by the sowing rate of 4,0 million units/ha, and of plants of the Erythrospermum kind – 3,5 and 4,0 million units/ha.