Technique Of Precise Nitrogen Fertilizer For High-yield Rice And Its Application In Donghai Country

The 58 expriments about precise nitrogen fertilizer for high-yield rice were carried out on two types soils in nine towns of middle and east area of Donghai country during 2003-2006. The proper values of three parameter were obtained for Stanford equation included amount of N requirement, N fertilizer recovery and N supply amount from soil during rice growth period. Then based on Stanford equation the precise nitrogen rate and its splitting application were figued out. The technique of precise nitrogen fertilizer for high-yield rice was establishedand used in a large area of rice production. Significant economic, social and ecological benefit were obtained.The summarize briefly relevant result as follows now:1. In yellow sandy soil at the middle of Donghai Country, the average base yield of rice, no nitrogen fertilizer application, was 353kg/667m~2, and average absorption nitrogen by rice was 5.4kgN /667m~2 from soil. There was a line relationship between the base grain yield and the corresponding N requirement to produce 100kg grains. The line equation was Y=632.3X-608.1(r=0.9959**). The average base yield in eastern Shajiang black soil was 403kg/667m~2, and average absorption nitrogen by rice was 6.4kg N/667m~2. The line equation was Y=557.2X-495.0(r=0.9935**).2.There was a quadratic relationship between the yield and the corresponding N requirement to produce 100kg grains in the two types of soil under high-yielding of rice. The quadratic equation was Y=-3308.4X~2+12590.4X-11381.5 N(R~2=0.8526**) on the yellow sand in central. And when X=1.9kg, Ymax=596.96kg. The quadratic equation was Y=-3439.3X~2+14780.6X-15204.1(R~2=0.6818**) on Shajiang soil regions of the east. And when X=2.14kg, Ymax=676.0kg. 3. Results of the validate test showed that Stanford eqation with three parameter values is a viable formula for calculating the total nitrogen amount. The yield of target, 600kg/667m~2, in sandy soil needed 1.9kg N per 100 kg grains, N recovery 38%. And the yield of target, 700kg/667m~2, in black sandy soil needed 2.1kg N per 100 kg grains. N recovery 40%. Calculation of the total amount of nitrogen credibility depended on soil nitrogen supply.4. Under the same nitrogen rate, the yield was impacted significantly by splitting the amount between the. In the yellow sandy soil of central area the ratio of tiller to panicle fertilizer of highest yield was 6:4. In the eastern Shajiang Black soil area the best ratio was 5.5:4.5.5. The economic, social and ecological benefit were obtained significantly by using technique of precise nitrogen fertilizer for high-yield rice in the Donghai country. The N application of demonstration reduce N 4-7kg/667m~2 than conventional fertilizering, but increase the yield 35-45kg/667m~2 and the income 90ï¿¥/667m~2. High-yield demonstration area has got to 27,600 hectares, and gained 38.8 million yuan addtionally.