施氮量和滴灌施肥频率对杂交棉氮素吸收和产量的影响

 在滴灌条件下进行了不同氮肥用量和滴灌施肥频率对杂交棉氮素吸收和产量影响的大田试验研究，试验中设置3个施氮（N）（270、360和450 kg·hm^-2）水平和2种滴灌施肥频率（5和10 d）。研究结果表明，不同氮肥用量和施肥频率显著影响杂交棉的干物质重、氮素积累量和子棉产量。在中氮（360 kg·hm^-2）和低氮（270 kg·hm^-2）水平下，增加滴灌施肥频率可显著促进杂交棉生长，增加干物质和氮素积累量；但是氮肥用量较大（450 kg·hm^-2）时，滴灌施肥频率对棉花的生长影响不大。因此，在杂交棉的水肥关键时期，适当地提高滴灌施肥频率可以提高棉花产量。

Effects of Nitrogen Rate and Fertigation Frequency on Nitrogen Uptake and Yield of Hybrid Cotton

Effects of nitrogen rate and fertigation frequency on nitrogen uptake and yield of hybrid cotton were investigated through field experiment under drip irrigation conditions. The experiment comprised six treatments, with three nitrogen (N) rates (270, 360 and 450 kg·hm^-2) and two fertigation frequencies (5 and 10 d). It was found that nitrogen rate and fertigation frequency significantly influenced nitrogen accumulation, dry mass and yield of hybrid cotton. Under 360 and 270 kg·hm^-2 of N rates, fertigation frequency with 5 d promoted cotton growth and induced a significant increase in N accumulation and dry mass of hybrid cotton, but there were not statistically different between two fertigation frequency treatments for 450 kg·hm^-2 of N level. It is recommended that increasing fertigation frequency could enhance yield of hybrid cotton in critical period of water and nutrition supply.