不同施氮量对甜瓜养分吸收、分配、利用及产量的影响

通过田间膜下滴灌栽培，研究不同氮素水平对甜瓜养分吸收、 分配及产量的影响。结果表明，增施氮肥显著提高了甜瓜的氮、 磷、 钾的积累量，特别是显著提高了甜瓜后期氮、 磷、 钾的积累量。在施P2O5 140 kg/hm2、 K2O 150 kg/hm2 的基础上施N 225 kg/hm2，甜瓜的养分吸收量和产量均为最高，各施氮处理甜瓜氮肥利用率在11%~29%之间，且随施氮量的增加而降低。甜瓜对钾的吸收量最高，氮次之，磷最少，表明甜瓜是喜钾作物。

Effects of nitrogen fertilization on nutrient uptake, assignment, utilization and yield of melon

An experiment was carried out to investigate the effects of different levels of nitrogen application on nutrient uptake, assignment, utilization and yield of melon in fields with drip irrigation. The results show that the accumulative amounts of N, P and K in melon plants are increased when more nitrogen fertilizer are applied, especially at the later growth stages of melon. Under the P2O5 application of 140 kg/ha, and K2O of 150 kg/ha, the nutrient uptakes, yield and sugar content of melon are the highest with 225 kg/ha N application. The nitrogen fertilizer use efficiencies are from 11% to 29% for the N treatments, and the nitrogen fertilizer use efficiency is increased with the reduction of nitrogen application rate. Among the nutrients required by melon, the amount of potassium is the highest, the amount of nitrogen takes the second place and the phosphorus is the least, which indicates melon is K-favoring crops.