Systemic phase of sorghum downy mildew. In time, the oospores that have developed in the mesophyll tissue between the firbrovascular bundles cause the leaf to shred (upper right).
Host/Plant: Grain sorghum (Sorghum bicolor, species of Euchlaena, Panicum, Pennisetum, and Zea)
Pest/Path: Sorghum Downy Mildew (Peronosclerospora sorghi)