NORTHERN CORN LEAF BLIGHT
Northern corn leaf blight is one of the most common diseases of maize in South Africa, and while yield losses are typically minimal, they can become significant if the planted cultivar is susceptible.
The disease is caused by the fungus Exserohilum turcicum, and generally occurs before silking. It prefers moderate temperatures (around 18°C to 27°C) with prolonged periods of moisture. The fungus overwinters on maize leaf debris.
The University of Minnesota Extension (UME) says that the disease is usually more severe when infection occurs earlier.
SIGNS AND SYMPTOMS
The UME says that typical symptoms of northern corn leaf blight are canoe-shaped lesions that range from 2,5cm to 15cm in length.
Initially, these lesions may be bordered by greygreen
