Abstract: Simple and practical cultivation practice with water saving and nitrogenreducing is beneficial to promoting the development of rice cultivation technology with resourceconserving and environmentfriendly. Taking production model as object, we examined the effects of watersaving and nitrogenreducing on annual yield, the characteristics of population quality, and nitrogen use efficiency of double cropping rice. The results showed that watersaving did not decrease annual yield of ratoon rice and double rice, with highest yield of 8.42 and 12.71 t·hm^-2  for both rice modes under the treatment of watersaving irrigation (W3). Compared with no nitrogen application (N0), annual yield under the treatment of nitrogenreducing (N2) and local nitrogen application level (N1) was significantly increased, with no significant difference between the treatments of N1 and N2. In addition, nitrogen agronomy efficiency, nitrogen partial factor productivity, and nitrogen use efficiency under the N2 treatment was higher than those under the N1 treatment. Therefore, to ascertain irrigating or not by the observation of the water layer in the soil layer using simple and homemade PVC tube, with reducing 24% and 20% nitrogen application respectively in the models of both ratoon rice and double rice, can achieve dual reduction of water and nitrogen use. It is a simple and practical cultivation technology with watersaving and nitrogenreducing in the rice production model.

Key words: fertilization, soil enzyme, microplate flurimetric assay method, red soil.