The effectiveness of cultivating soybean varieties of different maturity groups in the conditions of the central Ciscaucasia

Abstract

The studies were conducted in 2017-2019 at the experimental station of the Stavropol State Agrarian University in conditions without irrigation and on the basis of the experimental plots of Agrosakhar LLC with the use of irrigation. The territories of the research sites belong to the zone of unstable humidification, characterized by unstable and uneven precipitation during the growing season of soybeans, elevated air temperatures in summer, when soybean plants enter the phases of flowering and grain filling. At the experimental plots of the SSAU experimental station, the soil is represented by leached chernozem, at the experimental sites of Agrosahar LLC by ordinary chernozem. The purpose of the research is to determine the biological characteristics and efficiency of growing new, promising soybean varieties of the southern ecotype. It was found that the most quickly-ripening variety with a growing season of 96 days is the Bara variety, the longest growing season was noted in the mid-ripening Vilana variety – 129 days. The maximum photosynthetic potential of soybean crops was formed under irrigation conditions: quickly-ripening Selecta 101 variety – 1376, early-ripening Duar variety – 1678 and mid-ripening Zara variety – 2167 thous. m2.day/ha. In terms of yield, when growing soybeans without irrigation in the quickly-ripening group, the Lira variety stood out – 1.59 t/ha, in the early-ripening Selecta 201 variety – 1.75 t/ha and the midripening Zara variety – 1.94 t/ha, when irrigation was used in the quickly-ripening group, the Selecta 101 variety stood out – 2.34 t/ha, in the early-ripening Duar variety – 2.89 t/ha and the mid-ripening Zara variety – 3.14 t/ha. In the conditions of the SSAU experimental station without irrigation and in Agrosakhar LLC the largest profit in the amount of 16028 to 40912 rub./ha was obtained by cultivating the mid-ripening Zara variety with a yield of 1.94 - 3.14 t/ha, and the level of profitability ranged from 49.4 to 108.8%.