氮肥和栽植密度对水稻产量及氮肥利用率的影响

Nitrogen and transplanting density interactions on the rice yield and N use rate

针对部分地区水稻生产中氮肥用量过高及水稻移植密度越来越低的状况,选择2个早稻和2个晚稻品种为试验材料,设置施氮水平和移植密度互作试验,分析两因素及其互作对水稻产量和氮素利用率的影响。结果表明,氮水平和移植密度对水稻产量有显著影响,但其互作效应不显著;氮水平、移植密度及其互作对氮素利用率的影响均达显著水平。其中,低氮水平处理平均氮素利用率比高氮水平增加2.1%5~.6%;高密度的氮素利用率比低密度增加10.1%4~5.7%。说明提高移植密度,减少氮肥用量,既可通过大幅度增加有效穗来实现高产,又能显著提高氮素利用率。在资源日益短缺、生产成本渐高及面源污染越来越严重的形势下,密植少氮应是值得推广的水稻栽培技术。在本试验条件下,早稻移植密度在29.33~6.0万穴/hm2的基础上施N 153.11~69.4 kg/hm2、晚稻移植密度在23.13~0.0万穴/hm2的基础上施N 161.51~90.1 kg/hm2氮素是高产高效节氮的合理组合。

An experiment was carried out to study the interactive effect of increasing N fertilizer and reducing planting density on rice yield and N use rate.Two early rice varieties and two late rice varieties was used as test materials.The results showed that there was a significant influence of N level and transplanting density on the rice yield separately,but interactive effect was no significant.However,the influence of N level,transplanting density and their interactive effect on N use rate was significant.The average absorption rate of N fertilizer increased 4.2%-14.0% under the low N level in comparison with that under high N level with same planting density.The average absorption rate of N fertilizer under high transplanting density increased by 10.1%-14.6% in comparison with that under the condition of low density.The results of the trial indicated that both the rice yield and N use efficiency could be raised by properly increasing the transplanting density and decreasing the amount of nitrogen application.As a result,high yield of the rice and high N use rate can be obtained by increasing the transplanting density and decreasing the amount of nitrogen application.Take the yield and N use rate into consideration,the N fertilization rate was recommended as： N 153.1-169.4 kg/ha for the early rice with the transplanting density of 29.3×104-36.0×104 clusters/ha and N 161.5-190.1 kg/ha for the late rice with the transplanting density of 23.1×104-30.0×104 clusters/ha.