田间条件下通过用叶绿素计(SPAD)和手持式传感仪Greenseeker对小麦个体营养状况和小麦群体生长状态进行诊断,结果表明:返青拔节期间SPAD读数值与氮肥施用量有关,在施肥量小于300kgm-2的范围内随氮肥用量的增加SPAD读数值也在增加;小麦返青期叶片SPAD测定值与施肥量符合线性加平台的模型;返青-拔节期间的小麦叶片含氮量与叶绿素成正相关。氮肥的施用量影响小麦群体植被指数的变化,拔节期间的小麦叶片中的叶绿素含量和全氮含量与归一化植被指数(NDVI值)成正相关,施氮量与小麦NDVI值符合线性加平台的模型关系。田间可以通过监测群体和个体相结合的方法,对小麦的氮素营养状况进行快速诊断。
SPAD and Greenseeker were used to diagnose the individual nutritional status and colony growth state of wheat under field conditions. The results showed that the reading value of SPAD was related to the amount of nitrogen fertilizer during regeneration- jointing, and the value has also increased with the amount of nitrogen fertilizer increased in the fertilization within less than 300 kg hm-2. The leaf measured value of SPAD and the amount of fertilizer accorded with the linear plus plateau model during wheat regeneration. The wheat leaf nitrogen content was positively correlated with chlorophyll during regeneration- jointing. The amount of nitrogen fertilizer influenced the changes in vegetation index of wheat colony, the chlorophyll content and total nitrogen content in wheat leaf was positively correlated with NDVI, and the amount of nitrogen fertilizer and wheat NDVI accorded with the linear plus plateau model during regeneration. In the filed, through a method of combination of monitoring groups and individuals, the nitrogen nutritional status of wheat can be rapidly diagnosed.