Aerial Color Infrared Photography to Optimize In‐Season Nitrogen Fertilizer Recommendations in Winter Wheat

摘要: Remote sensing in the form of aerial color infrared (CIR) photography has been shown to be a useful tool for in-season N management winter wheat (Triticum aestivum L.). The objectives this study were (i) develop methodology predicting optimum fertilizer rates at growth stage (GS) 30 directly from CIR and (ii) quantify how relationships between these spectral indices respond different levels biomass crop. Field studies conducted three growing seasons (2002-2004) over wide range soil conditions across North Carolina using split-split plot randomized complete block design. Different planting date-seeding rate (PDSR) combinations applied create GS 30. 25 (N ) supply radiance, measure grain yield response . Aerial photographs obtained each site before applications. Significant PDSR observed. Optimum ranged 0 124 kg ha -1 1 with mean 55 Better prediction calculated relative high-N reference strips compared absolute bands or indices. Biomass measured influenced strength relationship When GS-30 was >1000 , best predictor (R 2 = 0.85) quadratic model based on radiance G band high strip (Rel Gs).