黄土高原半干旱区作物水分利用研究新途径

New approaches in researches of water use efficiency in semi arid area of Loess Plateau.

以黄土高原半干旱区农业生产条件 ,特别是土壤水分特性为背景 ,结合植物根冠通讯方面的有关研究进展 ,讨论了根化学信号在本地区的研究与开发潜力 .本地区节水农业的核心是提高作物的水分利用效率 ,其途径包括 :1 )减少土壤表面的无效蒸发量 ;2 )增加深层根量 ,减少表土中的根量 ,优化资源分配模式 ,提高繁殖分配比例 .根化学信号对这两方面都有重要影响 .基于目前的知识积累 ,应在根化学信号对作物生产力的影响方面作深入研究 。

Based on the background of agricultural conditions, especially the soil water characters in semi arid area of Loess Plateau, and on combining with the progress in field of root to shoot communication, the research and developmental potential of root chemical signals were discussed in this paper. The core of water saving agriculture in this area is to increase crop's water use efficiency (WUE). The ways for increasing WUE should be included: 1)decreasing inefficient evaporation from soil surface, and 2)increasing roots in deep soil, decreasing those in top soil, optimizing resource allocation pattern, and increasing reproductive allocation proportion. Root chemical signals affect strongly all the two aspects. According to the present accumulation of knowledge, the study on effects of root chemical signal on crop productivity can reveal some important theoretical problems.