冬小麦植株氮素营养诊断指标研究

Study on Plant Nitrogen Diagnostic Technique and Index of Winter Wheat

采用田间小区试验与植株硝态氮速测系统结合的方法,确定采用反射仪法速测冬小麦拔节期植株硝态氮含量对植株氮素营养进行评价。结果显示,冬小麦拔节期植株硝态氮含量缺乏临界值为1 000 mg/kg,充足评价指标为1 300 mg/kg;土壤合理的底肥施N量为75~150 kg/hm2;冬小麦拔节期合理的氮肥追施量应控制在100~150 kg/hm2;冬小麦最佳经济效益追肥量为117.86 kg/hm2。

Field experiment was adopted to study plant nitrogen diagnostic technique and index of winter wheat.The plant nitrate contents were measured at the jointing stage.From the experiment,the following results were obtained.The critical content of plant nitrate content for winter wheat was 1000mg/kg,the least ample evaluation index was 1300mg/kg.The reasonable amount of N for base application should be(75-150kg/hm^2.)The nitrogen fertilizer used for topdressing at the jointing stage was reasonable if it was between 100kg/hm^2 and 150 kg/hm^2.The most economic topdressing rate for winter wheat at jointing stage was(117.86kg/hm^2.)