节水农业及其生理生态基础

提高自然降水和灌溉水利用效率是节水农业要解决的中心问题。近年实践证明,通过提高水分利用率的途径增加农田生产力存在很大潜力,节水和增产的目标可能同时实现。为实现这一目标,需要研究确定植物水分亏缺的允许程度。植物各个生理过程对水分亏缺的敏感性不同,综合文献报道和作者研究结果,水分亏缺对与作物产量密切相关生理过程影响的先后顺序为:生长—蒸腾—光合—运输。在一定条件下,有限水分亏缺不会对作物最终经济产量造成影响,但却能显著提高水分利用效率。

Water-saving agriculture and its physio-ecological bases.

The key problem needed to be solved in water saving agriculture is to increase the utilization efficiency of rainfall and irrigation. Recent experiments and practices reveal that great petential exists in raising field productivity through the approaches of increasing plant water use efficiency (WUE); the aims of high yield and low water consumption may be achieved simultaneously. In order to reach this goal, it is necessary to study and determine the permitting degree of plant water deficit. Each physiological process of plants has different sensitivity to water deficit. On the basis of our experiment and other researchers' work, the effect of water deficit on physiological processes which are closely related to crcp yield is in the following sequence: Growth-Transpiration-Photosynthesis-Translocation. Under certain conditions, the limited water deficit does not influence the grain yield, and the WUE can be increased remarkably.