EVALUATION OF ECOLOGICAL PLASTICITY AND PRODUCTIVITY OF DIFFERENT SOYBEAN VARIETIES IN KAMA REGION OF THE REPUBLIC OF TATARSTAN

The article presents the results of a study to evaluating of yield formation characteristics and grain protein content in early-maturing soybean varieties from various breeding centers. The studies were conducted in 2023-2024 on gray forest soil in Kama region of the Republic of Tatarstan on the territory of Agrobiotechnopark of Kazan State Agrarian University. Eleven domestic and foreign varieties (EN Argenta, Samer 3, SK Aleksa, Vasilisa, Samer 2, Milyausha, Volzhanka, Vezelitsa, Vilana, ETs Flora, Duet) served as subjects of study. Agroclimatic conditions during the study years were characterized by periodic droughts during the soybean growing season. Analysis of biometric parameters revealed that plant height was primarily influenced by varietal characteristics, while root length was influenced by the agroclimatic conditions of the year. The following varieties were most resistant to root rot: Volzhanka, Aelita, ETs Flora, and SK Aleksa. Over the years of study the highest yields were obtained with the ETs Flora, Duet and EN Argenta varieties. The lowest yield variability across years was observed with Milyausha, ETs Flora and EN Argenta varieties. Milyausha variety had the highest protein content in soybean grain, while Volzhanka and Vezelitsa had slightly lower protein content. ETs Flora, Volzhanka, and Milyausha varieties demonstrated the highest protein yield in terms of protein yield per hectare of crop. The locally bred variety Milyausha, as well as the varieties Volzhanka and Vezelitsa, can be used in breeding programs to increase the protein content of soybean grains for the conditions of Kama region of the Republic of Tatarstan. Duet, ETs Flora and EN Argenta varieties are characterized by high yields and stable productivity (ecological plasticity) and are promising for cultivation in Kama region of the Republic of Tatarstan.