New Critical Nitrogen Curve Based on Leaf Area Index for Winter Wheat

• DOI: 10.2134/agronj2013.0213
• Publication Date: 2014-03-03T17:20:56Z
• Authors: Ben Zhao; Xia Yao; YongChao Tian; XiaoJun Liu; Syed Tahir Ata-Ul...; Jun Ni; WeiXing Cao; Yan Zhu
• Keywords: Winter wheat; Limiting; Dilution

Accurate forecasting of N required for plant growth can help optimize grain yields, farm profits, and use efficiency reduce the risk environmental pollution. The objectives this study were to: (i) establish a critical ( c ) dilution curve winter wheat Triticum aestivum L.) based on leaf area index (LAI), (ii) compare with curves that are dry matter, (iii) assess plausibility using new to estimate status wheat. Four field experiments conducted different application rates. Twenty plants from each plot sampled Feekes 3 10.5 stage analysis. relationship between LAI could be described by negative power equation, = 4.06LAI −0.4 , when values in range 1.4 7.5. For <1.4, however, constant value 3.58% was used. nutrition (NNI) ranged 0.34 1.31 during vegetative under rates 2009 2011. There significant positive differences NNI across four development stages. Validation models independent data produced root mean squared error 28 kg ha −1 . identified limiting nonlimiting used as reliable indicator in‐season stress grown eastern China.