中文摘要：

[目的]对田间小麦叶片进行无损监测，从数字图像处理的途径探讨田间小麦旗叶几何表型的测试方法，以期建立小麦旗叶几何表型与氮肥管理的关系。[方法]以宁麦13为试验材料，对其进行不同的氮肥处理．并采用数码相机及辅以数字图像处理的技术手段．探讨小麦旗叶的叶面积、长度和平均宽度与施氮量的关系。[结果]肥料处理是影响小麦旗叶几何表型的重要环境因子，不同的氮处理可令旗叶面积变化达4倍，小麦旗叶长度也可从15．87cm增长到25．33cm，因此小麦旗叶几何表型是鉴定前期肥料供应量的显著特征。旗叶表型与氮处理之间的高精度拟合关系表明该无损检测技术是研究小麦田间表型、氮肥及环境因子响应规律的可靠技术手段。[结论]该研究表明使用带标尺刻度的动态背景板数字图像处理技术是获取田间无柄及小叶作物几何表型的有效手段，其为田间条件下作物叶片器官生长动态的无损监测提供了一个可行的技术方案。

英文摘要：

[Objective] The aim was to conduct non-destructive monitoring on wheat leaf in field and discuss the method to measure geometric phenotype of flag leaf through digital image processing in order to establish relationship between geometric pheno- type of flag leaf and N fertilizer regulation. [Method] Ningmai 13 was applied with N fertilizers in different amounts to discuss relationship among area, length, average width of flag leaf and applied N fertilizers using digital camera and digital image pro- cessing technique. [Result] Fertilizer is a main environmental factor influencing geo- metric phenotype of flag leaf, for example, area of flag leaf would enlarge four times and the length would increase from 15.87 to 25.33 cm by different N fertilizer amount. Thus, geometric phenotype of flag leaf would reflect N fertilizer amount at early stage. The highly accurate relationship between phenotype and N fertilizer is a reliable tech- nique to study on rules of wheat phenotype, N fertilizer and environmental factors. [Conclusion] The research indicated that digital image processing technique with scale label and dynamic background plates is an effective method to obtain geometric phenotype of sessile crops and crops with little leaf, providing a feasible scheme for non- destructive monitoring on growth dynamic of leaf＇s organs.