Powdery mildew occurs under cool temperature (20-26 ºC) and is favored by cloudy weather. It can cause up to 40% yield loss. In the early stage the disease appears as light yellowish irregular spots on leaves which turn brown quickly. A powdery mass grows over the spots covering the entire leaf surface.

To control powdery mildew, planting of resistant cultivars, if available, is recommended. If using powdery mildew-susceptible cultivars, spray ethirimol at the rate of 200 ml a.i./ha beginning 3 weeks after emergence.

Cercospora leaf spot (CLS) commonly attacks mungbeans in the tropics. The disease is recognized by the appearance of leaf spots that are circular to irregularly shaped with grayish white centers and reddish brown to dark brown margins. It can cause yield losses of up to 58%.

The losses due to CLS disease can be avoided by planting resistant cultivars. Crop debris and weed hosts should also be removed at the time of planting. When susceptible cultivars are planted, spray with fungicides such as chlorothalonil at 2 kg a.i./ha at 2-week intervals.