Abstract:The experiment with micro plots under automatically inductive type of rain preventing condition was carried out to analyze the influence of regulated deficit irrigation on root and crown growth, characteristics of dry matter distribution, water consumption, root-shoot ratio and the wound flow of maize plant. Choosing the relative water content (the percent of field water-holding rate ) of soil as the upper and lower controlling limits, five treatments of water deficit were set, which were respectively the mild treatment（60%～70%FC） and the moderate treatment （50%～60%FC） at seedling stage, the mild treatment (60%～70%FC） and the moderate treatment （50%～60%FC） at jointing stage, moderate treatment at seedling stage and mild treatment at jointing stage, and the appropriate water content （70%～80%FC）was set as control in the whole growth period. The result showed that the regulated deficit irrigation did not change the total tendency of growth of root and crown of maize and the basic tendency of the growth of different organs in crown, but it increased the root-shoot ratio of plant and the distribution ratio of dry matters to ear in later stage of growth obviously, accelerated the transportation and distribution of photoassimilate to reproductive organs and enhanced the compensatory growth of root and crown after rehydration. The mild and moderate treatments at seedling stage of maize sustained higher root quality during deficit period, remarkably increased the root activity after rehydration, showed super compensatory effect of wound flow, kept higher wound flow at filling stage and sustained higher root-shoot ratio in later growth period, which was the appropriate water deficit treatment for coordinating the relationship of the growth of root and crown of maize.
