中文摘要：

目的研究不同生育期渍水对棉花氮素吸收、分配和利用的影响。[方法]在田间池栽条件下，通过设置盛蕾期渍水（WL1）和花铃期渍水（WL2）处理．研究不同生育期渍水对棉花氮素吸收、分配和利用的影响。[结果]wLl对棉花根系氮素吸收能力的影响大于WL2。WLl处理结束后20d时，棉花根系生物量、氮素吸收量和吸收速率分别显著降低38．1％、48．6％和53．O％；WL2处理结束后20d时，上述指标分别显著降低27-3％、46．O％和44．8％。WLl处理氮素向根和叶中分配比例明显提高，wL2处理氮素向产量器官中分配比例明显提高。WLl和WL2处理氮素生理利用率均有所提高。增幅分别为11．4％和44．4％。产量及其构成因素分析表明，WLl处理棉花铃数、铃重和皮棉产量分别显著降低40．5％、12．4％和49．5％：而W12处理棉花铃数、铃重和皮棉产量分别显著降低23．1％、6．9％和29．9％，降幅均小于WLl处理。[结论]盛蕾期渍水对棉花氮素营养和产量形成造成的负面影响大于花铃期渍水，棉花抗渍栽培工作应以防范盛蕾期渍水为重．渍水发生后加强氮素营养管理将有利于其恢复生长和降低产量损失。

英文摘要：

[Objective] This study aimed to investigate the effects of waterlogging in different growth stages on nitrogen （N） uptake, distribution, and utilization of cotton. [Method] A pool-culture experiment in field was conducted to investigate the effects of wateriogging through comparing WL1 （waterlogging at peak squaring stage） and WL2 （waterlogging at flowering and boll-forming stage） treatments with their controls respectively. [Result] The results showed that the effect of WL1 on N uptake of cotton root was stronger than WL2. At 20 days （d） after WL1 treatment, the root biomass （RB）, N uptake （NU）, and N uptake rate （NUR） significantly decreased by 38.1%, 48.6%, and 53.0% respectively. At 20 d after WL2 treatment, the RB, NU, and NUR significantly decreased by 27.3%, 46.0%, and 44.8% respectively. More N was distributed to root and leaf after WL1 treatment, and to square, flower, and boll after WL2 treatment. N physiological use efficiency increased by 11.4% and 44.4% after WL1 and WL2 treatments respectively. Further analysis showed that the effects of WL1 on yield and its components of cotton were stronger than WL2. The boll number, boll weight, and lint yield per plant significantly reduced by 40.5%, 12.4%, and 49.5% after WL1 treatment, and significantly decreased by 23.1%, 6.9%, and 29.9% after WL2 treatment, respectively. [Conclusion] The negative effects of water- logging at peak squaring stage on N nutrition and yield of cotton were stronger than waterlogging at flowering and boll-forming stage, indicating that more attention should be paid to waterlogging at peak squaring stage and sound N management can improve cotton regrowth and reduce yield loss after waterlogging.