不同土壤肥力条件下施氮量对稻茬小麦氮素吸收利用及产量的影响

Effects of N Application Rate on Nitrogen Absorption,Utilization and Yield of Wheat under Different Soil Fertility after Rice

为给江苏淮北麦区小麦高产栽培中氮素高效利用提供理论依据,以淮麦19和烟农19为材料,在高、中、低三种肥力土壤上研究了施氮量对小麦氮素吸收利用和产量的影响。结果表明,两个小麦品种各生育时期植株的吸氮量在各土壤肥力水平下均随施氮量的增加而提高,且与施氮量存在显著的线性正相关关系;氮肥利用率和产量随着施氮量的增加表现为先升后降的趋势,随土壤肥力的提高表现为上升趋势;氮素的吸收效率和氮肥的农学利用率在不同土壤肥力条件下均以不施氮处理最高。在高、中、低土壤肥力条件下,施氮量分别为202.5、270和337.5 kg.hm-2时,两个小麦品种氮肥利用率和籽粒产量均达到最高。

Took Huaimai 19 and Yannong 19 as materials, the effects of nitrogen rates on nitrogen uptake, nitrogen utilization and yield of wheat under high, middle, low soil fertility were studied. There were sig nificant linear relations between nitrogen application rate and nitrogen uptake rate of wheat plants in each periods; N utilization rate and yield increased with the increase of nitrogen application rate at first, then showed a downward trend, and showed an upward trend with the fertility level; the highest N absorption efficiency and agronomic N use efficiency were achieved at the lowest nitrogen rate in different soil fertility levels. The highest N utilization rate and grain yield were obtained when nitrogen rates were 202.5,270, 337.5 kg. hm^-2 under high, middle, low soil fertility levels, respectively.