Coupling Effects Of Water And Fertilizer On Yield And Quality Of Rice In Inadequate Irrigation

The rice was tested in the pot experiment. The split plot was designed in the pot experiment. The main treatment was nitrogen supplying; the subsidiary treatment was soil moisture during tiller-elongating stage. The study contents were: the demanding characteristics of water in rice, coupling effects of water and fertilizer on the forming characteristics of yield and quality in rice, index of plant type and quality with high quality and yield, physiological characteristics in later stage and nutrient metabolizing trait in plant, the connection of grain yield, quality and each index. The water and fertilizer coupling threshold of harmonizing yield and quality was put forward in this article. The results showed that:(1) The evapotranspiration of rice reduced following the reduce of the soil moisture. The threshold water stress was 73.35% during tillering stage and 75.25% during elongating stage.(2) The yield and quality of rice was affected by water, fertilizer and their interaction effects obviously, the optimum coupling of water and fertilizer will ensure the yield and quality of rice. The yield and quality were best when the nitrogen supplying content was270kg/hm2 and the water deficit was 6.22～7.13% during tillering stage and the nitrogen supplying content was 200kg/hm2 and the water deficit was 7.87～8.17%during elongating stage in this experiment.(3) In the condition of water and fertilizer coupling of deficient irrigation,the indexes of high-quality and yield plant and growing characteristics of rice were: The tiller number of single plant was 8.16 to 8.34 which can reduce the inefficacious tiller , increase the percentage of ear-bearing tiller and reduce the inefficacious expenditure; when the plant height were 82.20 to84.20 cm in high nitrogen supplying (270kg/hm2) and 72.02 to79.40cm in low nitrogen supplying (200kg/hm2) , the plant height and nitrogen harmonize excellent which can improve the efficiency of nitrogen; the leaf chlorophyll content have a rapid increasing rate the prophase and a low reducing rate in the anaphase; keeping a high photosynthetic rate, transpiration rate and stomatal conductance can increase the capacity of the dry matter production.(4) More nitrogen and phosphorus accumulatd in rice seeds can improve the content of protein and protein. Rice plants accumulating more phosphorus, potassium can contribute to the growth of rice plants and increase stress resistance. In the condition of water and fertilizer coupling of deficient irrigation, the water deficit was 6.22～7.13% during tillering stage and 7.87～8.17%during elongating stage in both fertilization treatments can show the optimum configuration results in this experimental.