Abstract: 【Objective】 The recognition and diagnosis of main maize leaf disease is introduced by the technique of image recognition in the paper. 【Method】 It adopts threshold method to do image segmentation, and uses area-marking method calculating the num of disease as well as wiping off redundancy dots. And then it uses Freeman link code to calculate form feather. 【Result】The research presents the exclusive feather of main maize leaf disease and confirms the flow of disease diagnosis. The results indicate that the precision of six kinds of maize disease recognition is higher than 80%. 【Conclusion】 It shows that this method is available for recognizing maize disease. And it also provides technique support for the automatic recognition of maize disease by compiling the system with reasonable process flow.

Key words: Maize leaf disease, Color feather, Form feather, Image segmentation, Area marking