Because symptoms in diseased plants can appear slowly, it is very difficult for farmers to notice and correctly diagnose the disease. Leaves are the most commonly observed part for detecting an infection. All the farmers have to do is to wave the phone in front of the leaf of a diseased plant and the app would diagnose it and suggest ways to maintain the crop. The plant diseases are a major thread to losses of modern agricultural production. Plant disease severity is an important parameter to measure disease level and thus can be used to predict yield and recommend treatment. The rapid, accurate diagnosis of disease severity will help to reduce yield losses.