Influence of sowing time on the yield of different varieties of soybeans

Abstract

Experimental studies were carried out on the experimental fields of the North Caucasus Research Institute of Mining and Piedmont Agriculture of the Vladikavkaz Scientific Center of the Russian Academy of Sciences. Trial establishment, phenological observations, and statistical processing of the obtained results were carried out using generally accepted methods. It was found that the highest seed yields for the studied varieties (Vilana, Slavia, Chara) were obtained in the third sowing period. So, for the Vilana variety (on average for 2018-2020, background - without fertilizers), the yield in the first period (10°C) was 1.87 t/ha, in the second (12°C) - 1.91 t/ha, in the third (14°C) - 2.06 t/ha, and in the fourth (16°C) - 1.97 t/ha. Indicators for the Slavia and Chara varieties were slightly lower. When mineral fertilizers were applied at the rate of P120K60, the yield of the studied varieties increased in comparison with the background P60K30. So, for the Vilana variety (average value over 3 years), the yield was higher in the first sowing period by 0.22 t/ha, in the second - by 0.31 t/ha, in the third - by 0.57 t/ha, and in the fourth - by 0.34 t/ha. From the given data it can be seen that the highest yield was noted in the third sowing period. A similar pattern was also observed for the Slavia and Chara varieties. So, for the Slavia variety, the yield in the third sowing period was 2.74 t/ha, in the fourth - 2.64 t/ha, in the second - 2.56 t/ha, in the first - 2.35 t/ha, and for the Chara variety, respectively: 2.60; 2.48; 2.45, and 2.31 t/ha.