Curvularia leaf spot

The fungus Curvularia penniseti is the primary pathogen responsible for the disease known as Curvularia leaf spot. This fungal agent is a significant concern in plant pathology as it specifically targets members of the Poaceae family, leading to compromised plant health and reduced agricultural productivity.

The primary hosts of this pathogen include pearl millet (Pennisetum glaucum), sorghum, and various forage grasses. The fungus is known for its ability to persist in diverse environmental conditions, making it a recurring challenge in regions where these crops are grown intensively.

Infected plants typically display distinct symptoms, which include the formation of small, circular to elongated chlorotic spots that eventually turn brown or black as the tissue dies. As the disease progresses, these lesions may expand and coalesce, leading to extensive leaf blight and, in severe cases, the premature death of the entire leaf foliage.

The development and spread of Curvularia penniseti are heavily dependent on climatic factors. High relative humidity and warm temperatures, typically between 22°C and 30°C, provide ideal conditions for sporulation and infection. The pathogen is primarily spread through wind-borne spores and rain splash from debris or infected seeds.

Effective management requires an integrated pest management approach. Key strategies include:

• treating seeds with systemic fungicides;
• implementing crop rotation to break the disease cycle;
• removing and destroying crop debris after harvest;
• applying foliar fungicides during early stages of infection.