Preliminary study on water-catching and controlled irrigation technology of rice

Characteristics of drought resistance and water logging tolerance of rice were used for a new water-saving irrigation mode, water-catching and controlled irrigation (WCCI). The mode maintained higher water depth after rainfall than continuous flooding irrigation (CFI) and kept low irrigation limit as controllable irrigation (CI) so as to improve rainwater use efficiency. Water consumption, irrigation quota, drainage quota, rainwater use efficiency, agronomy indexes and yield of rice under WCCI were investigated and the differences among CFI, CI and WCCT were also analyzed by plot experiments with hybrid rice cultivar “K you 818” as material. The results showed that water consumption under WCCI decreased 15.0% compared with CFI while increased 20.4% compared with CI. The irrigation quota after transplant under WCCI decreased 20.8%, 46.9% and drainage quota decreased 83.9%, 87.2%, respectively, compared with CFI and CI while rainwater use efficiency increased 36.84%, 48.02%, respectively. Plant height and productive panicle number under WCCI increased while leaf area index（LAI）decreased compared with CFI. Grain yield under WCCI was higher than that under CFI and CI. The results indicate that WCCI will be a water-saving, high-efficiency irrigation model of rice，and the model is suitable for rainy regions in South China.