应用数字图像分析技术进行冬小麦拔节期氮营养诊断

N Status Diagnosis of Winter Wheat by Using Digital Image Analysis Technology

传统的作物营养诊断如植株全氮、生物量和植株硝酸盐浓度测试等需要进行大量的田间取样和实验室分析,时效性不足,难以适应作物生长期间追肥诊断的需要。通过田间试验,应用数字图像技术对拔节期作物的氮营养状况进行了研究,发现冠层数字图像色彩参数可以用来表征冬小麦拔节期的氮营养状况。数字图像标准化红光值R/(R+G+B)与冬小麦常规营养诊断指标如叶绿素仪读数、茎基部硝酸盐浓度、植株全氮含量和地上部生物量之间的相关系数达到了0.809～0.946,是较好的表征作物氮营养状况的诊断指标。

Traditional plant N status diagnosis methods such as plant total N content,biomass and stem sap nitrate concentration test,which need destructive plant sampling and laboratory analysis,can not be used in regional scale due to its too time cost and labor cost.In this research,field experiment with digital image analysis method had been used in wheat N status diagnosis at shooting stage.The results showed the normalized redness of R/（R＋G＋B） well correlated with wheat N status parameters of SPAD chlorophyll meter readings,stem sap nitrate concentration,shoot total N content and upland biomass,and the correlation coefficients（r） with those parameters were 0-809-0.946.The normalized redness R/（R＋G＋B） is a good indicator of wheat N status by using digital image analysis method.