Puccinia sorghi

Fungal Disease

Puccinia sorghi

Fungal Disease

Puccinia sorghi

Fungal Disease

Puccinia sorghi

Fungal Disease

Puccinia sorghi

Fungal Disease

Maize, a staple crop, is susceptible to several diseases, and one of the most notable is rust caused by the fungus Puccinia sorghi. This disease thrives in warm, wet weather, with temperatures ranging from 16-23°C being ideal for its development. The rust manifests primarily through the formation of circular, powdery pustules on the maize plant, which progress from a cinnamon brown color to dark brown or black as they mature.

Symptoms

The most noticeable symptoms of maize rust are oval or elongated cinnamon brown pustules on both the upper and lower surfaces of the leaves. As the pustules mature, they rupture and release powdery red spores, which eventually turn dark brown-black. In severe cases, the pustules may spread to the tassels and ears, and the leaves can turn yellow and die prematurely. In some hybrids that are partially resistant, symptoms may appear as small chlorotic or necrotic flecks that release little or no spores.

Cause

This disease is caused by the rust fungus Puccinia sorghi, which spreads through wind-borne spores. It is particularly problematic in some popular sweet corn varieties, which tend to have little to no resistance to the disease.

Management

To manage maize rust, it’s essential to monitor for the characteristic symptoms early in the growing season. Avoiding excessive moisture and promoting good airflow around plants can help reduce the conditions that favor the disease. In cases of severe infection, resistant hybrids or fungicide treatments may be necessary to protect the crop.

Understanding the conditions that encourage the spread of maize rust and taking appropriate preventative actions can help reduce yield losses and ensure a healthier maize crop.