Effects of Irrigation on Photosynthetic Characteristics of Wheat under Drip Irrigation

摘要

In arid areas, wheat Growth and yield is extremely significant affected by irrigation, under different study of drip irrigation, the irrigation amount has impact on the physiological indicators of wheat, in order to help improve the efficiency of irrigation water use. In order to reveal the effects of irrigation on photosynthetic characteristics of the Wheat Under Drip Irrigation (WUDI), we designed four different irrigation treatments as W1 (315 mm), W2 (360 mm), W3 (405 mm) and W4 (450 mm) by test-pit experiments and investigated the effects of irrigation amount on photosynthetic physiological indexes of the WUDI. The results showed that the increased irrigation amount enhanced the wheat photosynthesis, but excessive irrigation would reduce the net photosynthetic rate and stomatal conductance of the plants (W3>W4>W2>W1). Regression analysis on the photosynthetic physiological indexes and irrigation amount indicated that the transpiration rate was significantly related with irrigation amount (R² = 0.99), while the photosynthetic rate and intercellular CO₂ concentration had moderate relations with irrigation amount (R² = 0.84). When the irrigation amount was 405 mm, the water utilization rate was highest and more photosynthetic products could be accumulated with more reasonable allocation.