Study on influence relations of the soil water deficit irrigation to rice leaf area and evapotranspiration in black soil areas of cold region

Effects of regulated deficit irrigation on leaf area and evapotranspiration in paddy rice was studied through regression analysis, relative soil saturated water content and field water depth was taken as index factors, homogeneous design and field experiment methods was used in the paper. It shows that, LAI and evapotranspiration reached a peak in flowering stage, the effects of LAI on yield was obvious in flowering stage and milk stage through significant correlation analysis of light transmittance and LAI, moderate increase of leaf area could be kept under regulated deficit irrigation in different growth period, loss of evapotranspiration was reduced 48.1% on average, the effect of water saving was obvious, rice yield was increased 1.29%.