Photosynthetic indicators of different soybean varieties in the Southern regions of Uzbekistan

This paper presents the data obtained on the study of bioecological and morphophysiological characteristics of different soybean varieties in the conditions of Surkhandarya region. During the experiments, photosynthetic indicators - leaf area, pigment concentration, net productivity of photosynthesis were determined. Based on the given results, it was noted that the above indicators change to different degrees depending on their biological and other characteristics. Researches have shown that the amount of pigments in leaves ranges from 45.51±0.15 to 37.28±0.22 under moderate moisture conditions, while this indicator ranges from 42.33±0.85 to 33.89±0.20 under limited moisture conditions. Observations of the expansion of soybean leaf area showed that the leaf area of plants grown in moderate conditions is on average 40% higher than the leaf area of plants in limited moisture conditions. The average value of the net photosynthetic productivity during the growing season was 5.5 and 6.2 g/m² per day for the Baraka and Ustoz MM-60 varieties under moderate moisture conditions, respectively. The minimum values were recorded for the Tomaris MAN-60 and Vilana varieties under limited moisture conditions, at 4.5 and 4,4 g/m² per day, respectively.