不同生态稻作区氮肥增产效应及其利用率

Effect of nitrogen fertilizer application on yield and nitrogen use efficiency in different ecological rice areas

在4个典型生态粳稻区,以广适性的5个品种为材料,研究氮肥对不同稻区产量影响,并分析氮肥利用率及其不同稻区施氮效果的差异。结果表明：氮肥施用显著提高不同稻区产量,施氮增产率及其贡献率大小顺序为温暖粳稻区〉寒冷粳稻区〉籼粳交错区〉冷凉粳稻区,寒冷粳稻区产量提高主要是有效穗数和千粒重的增加,而其它3个稻区产量的提高主要是有效穗数和每穗粒数的增加所致。生产等量的稻谷氮肥需要量的大小顺序为寒冷粳稻区〉冷凉粳稻区〉籼粳交错区〉温暖粳稻区。不同稻区对氮肥的利用效率存在差异,氮肥农学利用率大小顺序为温暖粳稻区〉籼粳交错区〉冷凉粳稻区〉寒冷粳稻区,氮肥吸收利用率大小顺序为籼粳交错区〉温暖粳稻区〉冷凉粳稻区〉寒冷粳稻区,4个稻作区的土壤氮素贡献率在61.10%~66.09%之间,说明各稻作区吸收的氮肥主要来自土壤,通过培肥地力,维持较高的地力水平对稻谷的超高产、高效具有重要意义。

Using 5 wide suitability varieties as material in four typical ecological rice areas, effect of different nitrogen fertilizer on yield, and nitrogen use efficiency in different rice areas. The results showed that the rice yield was increased significantly by nitrogen fertilization in different rice areas, the increase rate of production by nitrogen application was in order of warm ja- ponica area 〉 cold japonica area 〉 indica and japonica crisscross area 〉 cool japonica area. The increased yield in cold japonica area were mainly caused by effective panicles and 1 000 grain weight, but those in other three ecological rice areas were mainly increased by effective panicles and grain number per panicle. The nitrogen fertilizer requirements of producing the same amount of rice were in order of cold japonica area 〉 cool japonica area 〉 warm japonica area 〉 indica and japonica crisscross area. Ag- ronomic efficiency of nitrogen was in order of warm japonica area 〉 indica and japonica crisscross area 〉 cool japonica areas 〉 cold japonica area. Nitrogen absorption rate was in order of indica and japonica crisscross area 〉 warm japonica area 〉 cool ja- ponica area 〉 cold japonica area. The soil nitrogen contribution rate was 61.10% - 66. 09% in the four rice areas. It was concluded that the absorption of nitrogen in the rice area was derived mainly from soil, maintaining on a high level of soil fer- tility was great significance to the yield and nitrogen efficiency.