变水处理与短期遮荫对作物水分利用效率的影响

Effects of Changed Watering and Short-term Shade on Crop Water-use Efficiency

变水处理与短期遮荫对棉花水分利用效率的影响研究表明 ,在充分供水 -水分胁迫 -复水的变水处理过程中 ,短期遮荫使净光合速率、蒸腾速率、水分利用效率降低 ;光照 -遮荫 -光照期间 ,总的水分利用效率以水分胁迫的最高 ,充分供水的次之 ,复水处理最低 ,其中遮荫 40 %的水分利用效率高于遮荫 75%的处理 .回归分析表明 ,水分利用效率与光合速率表现出极显著正相关 ,两者回归直线的斜率随水分胁迫而增大 ,而水分利用效率与蒸腾速率的关系较弱 。

Study on effects of changed watering and short term shade on cotton( Gossypium hirsutum L.Zhongmain No.23) water use efficiency (WUE) showed that short term shade lowered net photosynthetic rate ( P n), transpiration rate ( E ) and WUE during the process of well irrigation water stress rewatering. Total WUE at water stress was highest, well watered WUE toke second place and rewatered WUE was lowest during full sun shade full sun period. WUE of 40% shading level was higher than that of 75% shading level. Correlation analysis indicated that WUE and P n showed extremely significant positive correlation, the slope of regressed line between WUE and P n increased with water stress progressive, but the relationship between WUE and E was weak, the most treatments didn′t show significant correlation.