缓/控释氮肥对夏玉米氮代谢、氮素积累及产量的影响

采用田间试验研究了缓/控释氮肥和不同施氮次数对夏玉米氮代谢、氮素吸收及产量的影响。结果表明,施氮显著增加了穗位叶硝酸还原酶活性、游离氨基酸含量、叶绿素含量和氮素积累量,提高了百粒重,增产20.93%~27.04%。与习惯两次施氮相比,一次性施用缓/控释氮肥和"苗肥30%+大口肥30%+吐丝肥40%"三次施氮的灌浆期游离氨基酸含量分别高2.77 mg g-1和4.07 mg g-1,氮素积累量分别提高了4.18%和9.74%,氮肥利用率分别提高了2.95和6.88个百分点,产量分别增加了4.88%和5.05%,实现了夏玉米增产和高效施肥。

Effect of Slow/Controlled Release N Fertilizer on N Metabolism,N Accumulation and Yield of Summer Maize

Field trial was used to study the effects of slow/controlled release N fertilizer and different frequency of N fertilization on N metabolism,N uptake and yield of summer maize.The results showed that the application of N fertilizer could significantly increase ear-leaf nitrate activities,free amino acid contents,chlorophyll contents and N accumulation.The application of N fertilizer improved the 100-grain weight and increased the 20.93%-27.04% of yield.The best effect was the treatment of three-off application of N fertilizer of 30% fertilizer at seeding stage,30% fertilizer at big trumpet stage and 40% fertilizer at silking stage prior to one-off application of slow/controlled release N fertilizer.Compared with the traditional two-off N fertilization,the free amino acid contents in these two treatments increased 4.07 mg g-1 and 2.77 mg g-1,fertilizer-nitrogen use efficiency increased 6.88% and 2.95%,the yield increased 5.05% and 4.88%,respectively.These treatments carried out high yield and benefit fertilization application of summer maize.