矮壮素配合氮肥全基施对华北夏玉米氮素利用的调控效应

为了解矮壮素(CCC)配合氮肥基施对夏玉米氮代谢及氮素利用率的调控效应,本研究以‘京农科728’(简称JNK728)和‘中单909’(简称ZD909)为材料,于2018和2019年在中国农业科学院新乡试验基地开展大田试验。试验设置常规氮肥处理(CN)和常规氮肥配合CCC处理(CN-CCC),包含0、62.5、125、187.0 kg·hm^-2 4个施氮水平。结果表明: 与常规氮肥处理相比,矮壮素配合氮肥全基施处理在施氮量为62.5和125 kg·hm^-2时,JNK728和ZD909产量在2018和2019年试验中平均分别增加了7.7%和5.0%。CCC处理提高了玉米生育期内功能叶硝酸还原酶、谷氨酰胺合成酶、谷氨酸合成酶和可溶性蛋白含量,促进了玉米氮素代谢。CCC配合低中施氮量(62.5和125 kg·hm^-2)条件下,JNK728和ZD909植株的含氮量平均分别增加17.6%和30.3%,籽粒含氮量分别增加10.3%和17.4%,氮肥偏生产力、氮肥农学效率、氮肥表观利用率和氮肥利用率分别较常规氮肥处理平均提高10.0%、15.7%、23.3%、24.8%和5.7%、15.0%、49.9%、71.7%。CCC配合适量氮肥全基施可以增强玉米氮素代谢,提高玉米氮素利用率和产量。在本研究中,CCC配合125 kg·hm^-2施氮量处理的夏玉米增产效果最佳。

Effects of basic application of chlorocholine chloride combined with nitrogen fertilizer on nitrogen use of summer maize in North China Plain

To clarify the effects of combined applications of chlorocholine chloride(CCC) and nitrogen fertilizer(CN) on nitrogen metabolism and nitrogen use efficiency of summer maize, we conducted a field experiment in Xinxiang experimental station of Chinese Academy of Agricultural Sciences in 2018 and 2019, with four nitrogen application rates(0, 62.5, 125 and 187.5 kg·hm^-2), and two maize varieties of Jingnongke 728(JNK728) and Zhongdan 909(ZD909). The results showed that across the two years CN-CCC increased maize yield by 7.7% and 5.0% under the nitrogen application rates of 62.5 kg·hm^-2 and 125 kg·hm^-2, respectively. CN-CCC increased the contents of nitrate reductase, glutamine synthetase, glutamate synthetase and soluble protein, and finally promoted nitrogen metabolism. Under the low and middle nitrogen application conditions(62.5 kg·hm^-2 and 125 kg·hm^-2), plant nitrogen content of JNK728 and ZD909 increased by 17.6% and 30.3%, grain nitrogen content increased by 10.3% and 17.4%, nitrogen partial productivity, agronomic efficiency of applied nitrogen, recovery efficiency of applied nitrogen, nitrogen use efficiency increased by 10.0%, 15.7%, 23.3%, 24.8% and 5.7%, 15.0%, 49.9%, 71.7%, respectively. In conclusion, appropriate basic application of CN-CCC could enhance nitrogen metabolism, increase nitrogen use efficiency and grain yield of summer maize. Our results showed that CCC combined basic nitrogen application of 125 kg·hm^-2 had the best effect.