Effect of water-saving irrigation on aerobic rice growth and yield in lowland condition

In order to evaluate the effects of water-saving irrigation on the aerobic rice growth and yield, as well as water productivity, the experiment was carried out in the field in Huibei Irrigation Experiment Station, Kaifeng, Henan province, during May to October in 2002. ne result showed that the biomass of root and leaf of aerobic rice decreased with the soil water potential decreased, the biomass of stem and leaf only reduced with decreasing of soil water potential just at tiller stage and maturity stage, Among the water treatments the biomass of rainfed was the lowest during the later stage. The results also showed slight water stress could promot Leaf Area Index( LAI) development, but reduced plant height, and had high effective tillers, so rainfed treatment could make a better growth environment for aerobic rice; while severe water stress reduced the LAI and the rate of effective tillers and the grain yield. According to our experiment result we suggested that the lowest soil water potential at 20cm of soil depth should not be less than -30kPa, It should be irrigated if it was less -30Pa.