Effects of water and nitrogen coupling on growth and physiological characteristics of overground part of rice

Based on the pot and field experiments, the effects of water and nitrogen coupling on growth and physiological characteristics of rice terrestrial part were studied. Results show that the number of tills and dry matter are higher and the height of plant is lower in the water-saving irrigation than those in sufficient irrigation. Leaf water potential and shoots dry matter weight are lower and the yield of rice is higher in low-level nitrogen treatment than those in high-level treatment. Yield of the least nitrogen and water treatment and the least nitrogen with medium water treatment are 6.01% and 11.68% higher than that of the least nitrogen with highest water treatment respectively. In high-level nitrogen treatment, dry matter weight increases but yield decreases. It indicates that high-level fertilizer is disadvantageous to the yield increase of plants under water-saving irrigation.