通过田间试验研究了在施磷一致的前提下,增加施氮量对棉花氮素吸收利用及产量的影响。结果表明,棉花不同时期不同部位吸氮量最高的均为N3P2处理;不同施肥处理下棉花各器官氮素的吸收表现不同,大概表现为铃>茎>叶>根系。与不施氮相比,施氮对棉花根系、茎、叶片和花铃的吸氮量有明显的促进作用。各处理植株对氮素吸收的最高峰出现在盛铃期,阶段积累吸收量为57.79～251.77 kg hm-2,占总量的34.99%～53.68%。氮养分吸收速率从苗期到盛蕾期增长缓慢,盛蕾期到盛花期各处理氮养分吸收速率开始明显加快。当生育期进行到盛铃期时,各处理均达到吸收速率最高值,其中,N3P2处理的吸收速率高于其他处理,此后棉株对氮的吸收速率逐渐降低。试验中,N3P2处理产量达2622.33 kg hm-2,显著高于其它处理。N3P2处理单株铃数、单铃重、纯收益最大。 Field experiments were conducted to study the effects of increasing nitrogen rates on nitrogen uptake and utilization and yield of cotton under the premise of consistent phosphorus application. The results showed that the highest N uptake by different parts of cotton at different periods was N3P2 treatment. The nitrogen uptake by different organs of cotton was different under different fertilization treatments, which could be described as bell> stem> leaf> root. Compared with no nitrogen application, nitrogen application significantly promoted the uptake of cotton by root, stem, leaf and flower bell. The peak of N uptake by plants in all treatment plants appeared in the stage of Shengling boll stage, and the accumulated uptake was 57.79 ~ 251.77 kg hm-2, accounting for 34.99% -53.68% of the total. The nitrogen nutrient uptake rate increased slowly from the seedling stage to Shenglei stage, and the nitrogen nutrient uptake rate started to obviously increase from Shenglei stage to full flowering stage. When the growth period reached its peak, all the treatments reached the highest absorption rate. Among them, the absorption rate of N3P2 was higher than that of other treatments, and then the nitrogen absorption rate of cotton plants decreased gradually. In the experiment, N3P2 production reached 2622.33 kg hm-2, which was significantly higher than other treatments. N3P2 bolls per plant, single boll weight, the largest net income.