Effects of Different Salt Stress on Physiological Growth and Yield of Drip Irrigation Cotton (Gossypium hirsutum L.)

This study adopted the method of barrel planting to artificially set the salt content of six different soils (CK:1.5 g kg(-1), T1:3.0 g kg(-1), T2:4.0 g kg(-1), T3:5.3 g kg(-1), T4:6.2 g kg(-1), T5:7.3 g kg(-1)) to study the effects of different degrees of mild salt stress on photosynthetic physiology, growth index and yield of cotton under drip irrigation. The results showed that with the increasing salt stress and the prolongation of stress time, the photosynthetic physiological indexes of cotton showed a downward trend (P < 0.01), and the plant height and leaf area were significantly affected by salt stress in the early growth stage. Furthermore, the comprehensive analysis showed that compared with moderate and severe salt stress, stomatal limitation was the cause of photosynthetic rate decline in cotton under mild salt stress at early growth stage, while non-stomatal limitation was at late growth stage. Photosynthetic parameters were closely related to the degree of salt stress, and cotton yield showed a good correlation with photosynthetic indicators. This experiment could provide a theoretical basis for the cultivation and management of cotton in mild saline-alkali land in Xinjiang.