论文部分内容阅读
通过田间试验比较研究了释放期分别为35天和60天的包衣尿素(以下称PCU35和PCU60)全量基施与普通尿素分次施用对夏玉米生长、产量、氮肥利用率的影响。结果表明,包衣尿素在田间的溶出较实验室慢,包衣尿素的养分溶出过程可以用y=ax2+bx+c的双曲线方程模拟。施氮在夏玉米生长和增产方面的作用不明显,不同处理间的夏玉米株高、最大叶幅和叶片叶绿素含量差异不大。施氮处理的夏玉米产量增幅在0.91%~11%之间,氮肥利用率在11.74%~22.98%之间,PCU35处理的夏玉米产量和氮肥利用率不仅高于PCU60,而且也高于施用普通尿素的处理。综上所述,在京郊正常气候条件下,选用释放期较短(如PCU35)的包衣尿素更易满足夏玉米生长期对氮素的需求。
Field experiments were conducted to compare the effects of graded urea (PCU35 and PCU60) with 35 days and 60 days release period on the growth, yield and nitrogen use efficiency of summer maize. The results showed that the dissolution rate of coated urea in the field was slower than that in the laboratory. The process of dissolution of coated urea could be simulated by hyperbolic equation of y = ax2 + bx + c. The effect of nitrogen application on the growth and yield of summer maize was not obvious. The differences of plant height, maximum leaf width and leaf chlorophyll content between different treatments were not significant. The yield of summer maize treated with nitrogen increased between 0.91% ~ 11% and the utilization rate of nitrogen fertilizer was between 11.74% ~ 22.98%. The yield and nitrogen use efficiency of summer maize treated with PCU35 were not only higher than that of PCU60, Urea treatment. In summary, the normal climatic conditions in the suburbs of Beijing, the use of shorter release period (such as PCU35) coated urea easier to meet the growth of summer maize nitrogen demand.