Phoma blight of chickpea

Phoma matteucciicola is a pathogenic fungus recognized as the causal agent of Phoma blight in chickpeas (Cicer arietinum). This disease is a significant threat to pulse production, particularly in regions with intensive cultivation and high humidity, leading to reduced seed quality and lower overall yield.

The host range of this pathogen is primarily restricted to chickpea. The fungus affects all parts of the plant, including seedlings, stems, petioles, leaves, and pods. Seedlings are particularly susceptible; if infected early, they may undergo damping-off, leading to poor plant stand and uneven crop development.

The symptoms of Phoma matteucciicola infection appear as dark, sunken lesions on stems and branches. These lesions may enlarge and girdle the stem, causing the upper part of the plant to wilt and die. On leaves, the lesions present as necrotic spots, while pods display dark, crater-like lesions that allow the pathogen to contaminate the seeds within.

Disease development is heavily influenced by environmental factors. High moisture levels, frequent rainfall, and moderate temperatures provide ideal conditions for the production and dispersal of conidia. The fungus persists in the soil on infected plant debris, making long-term survival possible even in the absence of a host crop for one or two seasons.

Integrated management is essential to control Phoma blight. This includes planting disease-free, fungicide-treated seeds and implementing crop rotation schemes with non-host crops to break the pathogen's life cycle. Additionally, deep tillage helps bury infected debris, while timely foliar fungicide applications during the vegetative and flowering stages are crucial for managing outbreaks.