摘要：

阐明叶面肥不同施氮量对玉米氮素积累转运利用的影响。试验时间为2021—2022年,采用随机区组设计,以玉米品种利禾1号为研究对象,设置不施肥处理(CK)、常规根部施肥处理(CF)、叶面减氮20%处理(LF1)、叶面常规施氮处理(LF2)、叶面增氮20%处理(LF3),分析叶面氮肥不同施用量与不施肥及常规根部施肥对玉米氮素积累转运利用的差异。结果表明,玉米茎氮素积累量和叶氮素积累量随生育期的推进呈先升高后降低的趋势,于抽雄吐丝期达到最大值。单株氮素积累量随生育期的推进逐渐升高,于成熟期达到最大值,LF2处理的单株氮素积累量最高。吐丝期前叶片中氮素分配占比最高,吐丝期后籽粒氮素分配占比逐渐升高,于成熟期达到峰值;CK的籽粒氮素积累占比最低,2021年LF1处理的籽粒氮素分配占比最高,2022年LF3处理的籽粒氮素分配占比最高。氮素转运率和氮素转运对籽粒的贡献率随施氮量的增加先升高后降低,氮素收获指数、氮素利用率随施氮量的增加而降低;2021,2022年LF1处理、LF2处理、LF3处理的氮素利用效率均高于CF处理,且LF1处理的氮素利用率最高。2 a叶面施氮处理的氮素吸收效率均高于CF处理。各处理的穗长、穗粗、穗行数无显著差异,CK的秃尖长最长,各施氮处理的行粒数和百粒质量均大于CK,CF处理的生物产量最高,LF1处理的籽粒产量和收获指数最高,各处理的籽粒产量显著高于CK,收获指数随施氮量的增加而降低。因此,在内蒙古中西部地区玉米以LF1叶面施氮处理下能获得较好的生长效果。

关键词: 玉米, 叶面肥, 施氮量, 氮素利用率

Abstract:

The aim was to elucidate the effects of different foliar fertilizer nitrogen application amounts on nitrogen accumulation,translocation,and utilization in maize.This experiment was conducted in 2021—2022 using a randomized block design,with maize variety Lihe 1 as the research object.No fertilization treatment (CK),conventional root fertilization treatment (CF),foliar nitrogen reduction treatment of 20% (LF1),foliar conventional nitrogen application treatment (LF2),and foliar nitrogen increase treatment of 20% (LF3) were set up to analyze the differences in nitrogen accumulation,translocation,and utilization of maize under different nitrogen fertilizer application amounts,no fertilization and conventional root fertilization.The results showed that the nitrogen accumulation in maize stems and leaves showed a trend of first increasing and then decreasing with the advancement of the growth stage,reaching the maximum value at the tasseling and silking stage.The nitrogen accumulation per plant gradually increased with the advancement of the growth stage and reached its maximum value at mature stage,the nitrogen accumulation per plant was highest in the LF2 treatment.The proportion of nitrogen distribution in leaves was highest before the silking stage;after the silking stage,the proportion of nitrogen distribution in grains gradually increased,reaching its peak at mature stage.The CK had the lowest proportion of nitrogen accumulation in grains,while the LF1 treatment had the highest proportion of nitrogen distribution in grains in 2021,and the LF3 treatment had the highest proportion of nitrogen distribution in grains in 2022.The nitrogen transport rate and the contribution rate of nitrogen transport to grains first increased and then decreased with the increase of nitrogen application amounts,the nitrogen harvest index and nitrogen utilization efficiency decreased with the increase of nitrogen application amounts;in 2021 and 2022,the nitrogen utilization efficiency of LF1 treatment,LF2 treatment,and LF3 treatment was higher than that of CF treatment,and the nitrogen utilization efficiency of LF1 treatment was the highest.The nitrogen absorption efficiency of foliar nitrogen application treatment for two years was higher than that of CF treatment.There were no significant differences in ear length,ear thickness,and ear row number among the treatments.CK had the longest bald tip length,and the row number and hundred grain weight of each nitrogen application treatment were higher than those of CK.CF treatment had the highest biological yield,while LF1 treatment had the highest grain yield and harvest index.The grain yield of each treatment was significantly higher than CK,and the harvest index decreased with increasing nitrogen application amounts.Therefore,maize can achieve better growth effects under LF1 foliar nitrogen application in the central and western regions of Inner Mongolia.

Key words: Maize, Foliar fertilizer, Nitrogen application amount, Nitrogen utilization efficiency