Effects of Water Disposal on Growth and Yield of Rice

To study the effects of water disposal on the growth and yield of rice,the method of the pot culture was adopted in this experiment,and three levels were designed in tillering stage,booting stage,blooming stage and milk stage of rice.Comparing with the treatment of keeping water flooding,there were three other treatment.Treatment H1,soil water potential was 0 kPa(90%~100% of soil saturation contains water);treatment H2,soil water potential was-30 kPa;treatment H3,soil water potential was-50 kPa.The results showed that in tillering stage the effects of water stress on tillering number,LAI,and plant height of rice were evident,the yield was seriously affected with no enough effective panicles in unit area,and the average yield of the treated was 29.5% lower than that of the control.In booting stage,owing to water stress on rice,the rice tillering panicles was restrained,the yield was seriously affected because there were not enough effective panicles in unit area,and fewer of the grains of panicle and light of weight of 1000-grain.The average effective panicles of the treated was 26.7% lower than that of the control,the average yield of the treated was 63.8% lower than that of the control.In blooming stage,1000-grain weight of treatment H1 was 12.9 % higher than that of the control,and the difference was extremely significant(P0.01),the yield of treatment H1 was higher than that of the control,the yield of treatment H2 and treatment H3 was lower than that of the control,and the difference was extremely significant(P0.01).In milking stage,1000-grain weight of treatment H1 was 11.2 % higher than that of the control,and the difference was extremely significant(P0.01),the yield of treatment H1 was 12.76% higher than that of the control,and the difference was extremely significant(P0.05).