控制交替沟灌中灌水控制下限对玉米叶片水分利用效率的影响

控制交替沟灌是通过调节作物生理过程实现节水的一项新技术。试验结果表明，在控制交替沟灌条件下，叶片蒸腾速率随着土壤含水量的降低而下降，而叶片光合速率则在土壤含水量降到某一数值以前没有显著的变化，从而造成叶片水分利用效率在较轻的水分胁迫下会有一定程度的提高。从叶片水分利用效率的角度分析，控制交替沟灌的灌

Effects of Irrigation Low Limits on Leaf Water Use Efficiency in Maize under Controlled Alternative Furrow Irrigation

Controlled alternative furrow irrigation(CAFI)is a new technique of saving water by adjusting plant physiological process. Experimental results showed that under CAFI, leaf transpiration rate decreases linearly as irrigation low limit drops, but leaf photosynthetic rate reduces little before the irrigation low limit drops to a critical level. Therefore, leaf water use efficiency will be raised in some content with light water stress. On the view point of leaf water use efficiency, the suitable irrigation low limit is 70% of field capacity under CAFI. Compared with the traditional irrigation treatment, transpiration consumption reduced 9. 8%, photosynthetic yield declined only 2.1%, and leaf water use efficiency raised 8. 8%.