Formation of seed yield of soybean varieties with different growing periods in the western Forest-steppe

Abstract

Purpose. To establish the influence of sowing terms and seeding rates on the formation of seed yield of soybean varieties with different growing periods in the Western Forest-Steppe natural zone of Ukraine. Methods. Field experiment, calculation and weight, mathematical statistics. Results. It was found that the studied soybean varieties with different growing periods react differently to growing conditions. Among the studied factors, the seeding rate, more than the sowing period, influenced the formation of soybean seed yield. Inparticular, the studied soybean varieties Diadema Podillya, KiVin, Knyazhna and Khutoryanochka in all terms of sowing, the highest grain yield formed at the seeding rate of 900 thousand germinating seeds per 1 ha, while the Triada variety – at the seeding rate of 700 thousand germinating seed sper 1 ha. The increase in yield compared to the seeding rate of 700 thousand germinated seeds per 1 ha was in the Diadema Podillya variety – 8,9-19,2%, in the KiVin variety – 12,4-15,6%, in the Knyazhna variety – 16,0-22,9% and in the Khutoryanochka variety – 4,2-10,1%. Reducing the seeding rate to 500 thousand germinating seeds led to a decrease in productivity for all sowing periods, in the Diadema Podolia variety – by 15,3-23,7%, in the KiVin variety – by 19,6-26,0%, in the Knyazhna variety – by 13,6-18,3%, in the Khutoryanochka variety – by 9,9-11,0% and in the Triada variety – by 17,8-25,7%. Higher indicators of seed yield all the studied soybean varieties formed during the late sowing period. Conclusions. The studied factors had a significant influence on the formation of seed yield of all soybean varieties that were studied – the timing of sowing and seeding rates, as well as the weather conditions of the growing season. The studied soybean varieties reacted differently to a decrease or increase in the seeding rate, however, higher yield indicators were formed due to the late sowing period.