Eleusine anthracnose

Eleusine anthracnose is a fungal disease caused by the pathogen Colletotrichum eleusines. This fungus primarily affects grasses, particularly finger millet (Eleusine coracana), disrupting vascular tissue functions and drastically reducing the physiological efficiency of the host plant throughout its growth cycle.

The host range of Colletotrichum eleusines is primarily focused on members of the Poaceae family. The fungus invades all aerial parts of the host plant, including leaves, stems, and seed heads, often leading to systemic weakening of the plant and substantial reduction in grain yield and quality.

Symptoms typically begin as small, water-soaked spots on the foliage that eventually expand into dark, necrotic lesions. As the infection matures, the centers of these lesions develop black, pin-head-sized structures known as acervuli. Infected plants often show signs of chlorosis, premature wilting, and in severe cases, lodging occurs due to the weakening of the stem base.

Environmental conditions play a critical role in the severity of the outbreak. The fungus thrives in high humidity and warm temperatures, which are essential for sporulation and the dispersal of conidia. The pathogen survives in dormant mycelium within crop residues, soil, and occasionally within the seed, serving as a primary inoculum source for subsequent planting seasons.

Integrated disease management is essential for control. This includes the use of disease-resistant varieties and the application of systemic seed treatments to prevent early-season infection. Furthermore, agricultural practices such as crop rotation, balanced fertilization to improve plant vigor, and the thorough removal or deep incorporation of crop debris are vital to reducing the infection potential in the field.