摘要
旨在建立宁夏引黄灌区滴灌玉米临界氮稀释曲线模型,探讨氮营养指数(NNI)用于实时诊断和评价玉米氮素营养状况的可行性,为实现滴灌玉米合理施用氮肥提供理论依据。以天赐19为试验材料,采用滴灌水肥一体化技术,设6个氮肥水平,利用2年定位试验构建并验证了临界氮稀释曲线模型。结果表明:(1)在一定范围内,滴灌玉米干物质积累量随施氮水平的提高而增加,根据方差分析结果,将玉米各生育时期的地上部生物量分为限氮和非限氮2类;(2)滴灌玉米植株氮浓度均随着施氮量的增加而提高,但随生育期的推进和地上部干物质量的增加,玉米植株氮浓度均呈下降趋势;(3)滴灌玉米临界氮浓度(Nc)、最大氮浓度(Nmax)和最小氮浓度(Nmin)稀释模型与地上部干物质累积量之间均呈现幂函数关系,其决定系数R^2分别为0.982、0.907、0.918,利用均方根误差(RMSE)和标准化均方根误差(n-RMSE)的验证表明,该模型稳定性好,误差范围小;(4)氮素营养指数模型(NNI)可衡量滴灌玉米氮素营养状况,滴灌水肥一体化条件下,宁夏引黄灌区玉米以270 kg hm^-2为最佳施氮量;(5)根据模型推算,NNI与相对吸氮量(RNupt)、相对地上部生物量(RDW)和相对产量(RY)均极显著相关。本研究所建立的滴灌玉米临界氮稀释曲线模型和氮营养指数模型,能够精准地预测水肥一体化条件下玉米小喇叭口期至成熟期的氮素营养状况,为优化玉米的氮素管理提供指导。
The objective of this study was to establish the critical nitrogen dilution curve of maize in Yellow River irrigation area of Ningxia province,China,and to study the feasibility of the nitrogen nutrition index model(NNI)for real-time diagnosing and evaluating nitrogen nutrition in maize,which would provide theoretical basis for rational nitrogen fertilization of drip-irrigated maize.The research was carried out with‘Tianci 19’,using the integrated technology of drip irrigation and fertilizer with six nitrogen levels.The critical nitrogen dilution curve model was constructed and verified by a 2-year fixed position experiment.Within a certain range,the dry matter accumulation of drip-irrigated maize increased with the increase of nitrogen application rate.According to the variance analysis,the aboveground biomass in maize growth period was divided into two types:nitrogen limited and nitrogen non-limited.The nitrogen concentration of drip-irrigated maize plant increased with the increase of nitrogen application rate,while decreased with the extension of growth period and the increase of aboveground dry matter weight.The critical nitrogen concentration(Nc),maximum nitrogen concentration(Nmax)and minimum nitrogen concentration(Nmin)dilution models of drip irrigated maize showed a power function relationship with the aboveground dry matter accumulation,with the determination coefficient R^2 of 0.982,0.907,and 0.918,respectively.The verification using root mean square error(RMSE)and normalized root mean square error(n-RMSE)showed that the model had good stability and small error range.NNI can be used to measure the nitrogen nutrition status of drip-irrigated maize.Under the integration condition with drip-irrigation and fertilizer,the optimal nitrogen application rate for maize grown in Yellow River irrigation area of Ningxia should be 270 kg hm^-2.According to the model calculations of,NNI with relative nitrogen uptake(RNupt),relative aboveground biomass(RGW)and relative yield(RY)reached extremely significant levels.The critical nitrogen dilution curve model and nitrogen nutrition index model established in this study can accurately predict the nitrogen nutrition status of maize from the bell stage to the maturity stage under the integrated condition with water and fertilizer,so as to provide guidance for optimizing the nitrogen management of maize.
作者
付江鹏
贺正
贾彪
刘慧芳
李振洲
刘志
FU Jiang-Peng;HE Zheng;JIA Biao;LIU Hui-Fang;LI Zhen-Zhou;LIU Zhi(School of Agriculture Ningxia University,Yinchuan 750021,Ningxia,China)
出处
《作物学报》
CAS
CSCD
北大核心
2020年第2期290-299,共10页
Acta Agronomica Sinica
基金
国家自然科学基金项目(31560339)
宁夏高等学校科研项目(NGY2017025)资助~~
关键词
水肥一体化
玉米
植株氮浓度
临界氮稀释曲线
氮营养指数
water-fertilizer integration
maize
plant nitrogen concentration
critical nitrogen dilution curve
nitrogen nutrition index
