摘要
为构建基于叶面积指数(LAI)的夏玉米叶片临界氮浓度稀释曲线,于2018、2019年在关中地区进行了不同水氮供应的田间试验,试验设置了3个水分水平:雨养(RF)、亏缺灌溉(DI)和充分灌溉(FI),4个氮肥水平:0、90、150、210 kg/hm^(2),研究基于LAI的夏玉米叶片临界氮浓度稀释曲线对不同水分供应的响应,分析氮营养指数(NNI)与相对产量的定量关系。结果表明:夏玉米LAI与叶片氮浓度之间符合幂函数关系。基于LAI的叶片临界氮浓度稀释曲线在RF处理下年际差异显著(P <0.05),但在DI和FI处理下年际差异不显著(P> 0.05)。在RF处理下基于LAI的叶片临界氮浓度稀释曲线的稀释速率显著高于DI和FI处理(P <0.05),但DI和FI处理间无显著差异(P> 0.05)。将DI和FI处理的临界氮稀释曲线并置拟合,得到灌溉处理下基于LAI统一的叶片临界氮浓度稀释曲线(R2=0.90,P <0.01)。在试验施氮量区间,氮营养指数NNI随施氮量的增加而增加,变化范围为0.62~1.16。当NNI大于等于0.97时,夏玉米产量不再随NNI的增加而增加,此时RF处理的产量为最大产量的85%,DI和FI处理的产量均高于最大产量的99%。因此,该地区推荐的水肥一体化水氮用量为灌水75%ETc(ETc为夏玉米需水量)和施氮150 kg/hm^(2)。
The critical nitrogen dilution curve can be used to diagnose crop nitrogen nutrition. In order to construct the leaf critical nitrogen concentration dilution curve of summer maize based on LAI,the field experiments with different water and nitrogen applications were carried out in Guanzhong Plain from 2018 to 2019. Three water levels( rain fed( RF),deficit irrigation( DI) and full irrigation( FI)) and four nitrogen levels( 0 kg/hm^(2),90 kg/hm^(2),150 kg/hm^(2) and 210 kg/hm^(2)) were set to study the response of leaf critical nitrogen dilution curve based on LAI to different water levels. The quantitative relationship between nitrogen nutrition index( NNI) and relative yield was analyzed. The results showed that the relationship between LAI and leaf nitrogen concentration was power function. The leaf critical nitrogen dilution curve based on LAI under RF was significantly affected by the interannual variation( P < 0. 05),while the leaf critical nitrogen dilution curve based on LAI under DI and FI was not significantly affected by the interannual variation( P > 0. 05). The dilution rate of leaf critical nitrogen dilution curve based on LAI under RF was significantly higher than that under DI and FI( P < 0. 05),but there were no significant difference between DI and FI( P > 0. 05). The critical nitrogen dilution curves of DI and FI treatments were fitted,and a unified critical nitrogen dilution curve was obtained( R2= 0. 90,P <0. 01). In the range of nitrogen application,NNI was increased with the increase of nitrogen application,and the range was 0. 62 ~ 1. 16. The relative yield of RF treatment was 85% of the maximum yield,and that of DI and FI treatment was over 99% of the maximum yield. Therefore,75% ETc( ETcis the water demand of summer maize) and 150 kg/hm^(2) of nitrogen were recommended for fertigation in Guanzhong Plain. This results can provide reference for the precise management of water and nitrogen of summer maize in Guanzhong Plain.
作者
陆军胜
耿晨鸣
崔晓路
李梦月
胡田田
LU Junsheng;GENG Chenming;CUI Xiaolu;LI Mengyue;HU Tiantian(Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas,Ministry of Education,Northwest A&F University,Yangling,Shaanxi 712100,China)
出处
《农业机械学报》
EI
CAS
CSCD
北大核心
2021年第4期319-326,共8页
Transactions of the Chinese Society for Agricultural Machinery
基金
公益性行业(农业)科研专项(201503124)。
关键词
夏玉米
临界氮浓度
水肥一体化
叶面积指数
氮营养指数
summer maize
critical nitrogen concentration
fertigation
leaf area index
nitrogen nutrition index
