追氮对膜下滴灌马铃薯氮素吸收积累规律及利用效率的影响

Effects of N Additional Fertilization on Nitrogen Absorption and Accumulation and Use Efficiency of Potato Under Mulched Drip Irrigation

以紫花白为试验材料,研究了不同追氮处理对膜下滴灌马铃薯氮素吸收积累规律及其利用效率。结果表明:随施氮量的增加,马铃薯对氮素的吸收和积累都呈增加趋势,而氮肥利用率及生产效率都呈递减趋势;施氮量为270.0 kg/hm2时,马铃薯氮素含量、累积吸收量最大;施氮量为67.5 kg/hm2时,氮素利用效率最高;而施氮量为202.5 kg/hm2时,产量最高。马铃薯块茎产量与氮素吸收量、氮素利用率存在显著正相关,而与施氮量相关不显著,氮素吸收量与施氮量呈极显著正相关。

Nitrogen absorption, accumulation and utilization efficiency were studied of potato cv. Zihuabai for various treatments of N additional fertilization under mulched drip irrigation conditions. With the application rate of nitrogen increasing, potato nitrogen absorption and accumulation increased, while nitrogen use efficiency and production efficiency decreased. When the application rate of nitrogen was at 270.0 kg/ha, the potato nitrogen content and cumulative absorption reached maximum; when the application rate of nitrogen was at 67.5 kg/ha, the nitrogen use efficiency was the highest; and when the application rate of nitrogen was at 202.5 kg/ha, the production was the highest. Potato production was significantly and positively correlated to N uptake and N use efficiency, but not to N application rate. N uptake was highly significantly and positively correlated to N application rate.