Comparison of Physiological, Biochemical and Root Traits of Tolerant and Sensitive of Mung Bean (Vigna Radiata L.) Cultivars Under Drought Stress and Seed Priming Conditions

Drought stress significantly impairs the performance and physiological function of mung bean. This plant is a summer nitrogen stabilizer legume with a short growth period that is compatible with environmental conditions, rich in protein and is widely cultivated in many areas as the second crop following wheat. Seed priming in many plants and legumes increases photosynthesis, improves plant resistance to stress, and accelerates plant root development.To investigate the effect of soil moisture level on physiological traits and roots of a mung bean plant, a greenhouse experiment was conducted in 2017. Soil moisture treatments included 80, 60, and 40% of field capacity and mung bean cultivars, namely Uzbek (sensitive) and line 73-726A (tolerant). Seed priming involved seed hydropriming and non-priming seeds in split factorial based on a completely randomized design with three repetitions. At the flowering stage, physiological traits and root traits were evaluated at the end of the growing season.Under mild stress conditions, the photosynthesis rate was nearly twice that of severe stress. In drought stress treatments, Line 73-726-A had a higher photosynthesis rate than the Uzbek cultivar. Seed priming increased the rate of photosynthesis compared to non-priming conditions in both cultivars. Also, hydropriming improved physiological traits, such as the photosynthetic rate, stomatal conductance and chlorophyll fluorescence. Moreover, seed priming caused better root development and increased ascorbic acid content than the control. In general, Line 73-726-A had a significant advantage over the Uzbek cultivar in all studied traits. In general, it can be concluded that hydropriming can be an effective strategy to reduce the effects of drought stress in this plant