Recovery of Grain Yield and Protein with Fertilizer Application Post Nitrogen Stress in Winter Wheat (Triticum aestivum L.)

Unfavorable weather conditions and lack of appropriate farm machinery often delay N application. This results in nitrogen (N) deficiency during the vegetative early reproductive growth stages winter wheat. The objective this study was to evaluate impact application timings (from tillering flag leaf stages) on wheat grain yield protein. conducted across 12 site–years Oklahoma, US. treatments included a non-fertilized check, pre-plant 100 kg ha−1, ten in-season at ha−1. treatment applications were initiated point when an visually identified by comparing check. applied progressive order every seven growing degree days (GDD > 0 °C) until cumulative GDD 63 reached after visual (DAVD). All increased protein as compared showing that yield-limiting factor. made post Feekes 8 decreased applications. Across data set, timing corresponded range 21 63DAVD. suggested forgoing stage 7, even highly apparent before stage, had no negative yield, it some cases. plant developmental which takes place is more critical than level deficiency. Our show fertilizer should be posteriorly crop dormancy maximize both protein, plants can recover from are late-vegetative phase (Feekes 7). document shows producers have much wider window traditionally believed.