Phoma blight of chickpea

Boeremia noackiana is a pathogenic fungus responsible for Phoma blight in chickpea crops. Historically associated with the Phoma genus, this pathogen poses a significant threat to legume production globally. It is capable of causing extensive damage to plant tissues, leading to yield loss and reduced grain quality.

The primary host for this pathogen is the chickpea (Cicer arietinum). The fungus affects various plant parts, including stems, petioles, leaves, and pods. It survives in infected crop debris left in the field and can also be seed-borne, which facilitates its persistence and spread across agricultural lands over successive seasons.

Symptoms initially appear as brown, elongated lesions on the stems. As the infection progresses, these lesions may expand, potentially girdling the stem. A defining diagnostic feature is the presence of pycnidia — small, black, dot-like fruiting bodies embedded within the necrotic tissue, which serve as the primary source of secondary inoculum during the season.

The development and spread of the disease are heavily influenced by environmental factors. High humidity, frequent rainfall, and moderate temperatures provide optimal conditions for spore production and dissemination via splashing rain and wind currents. Dense canopy architecture exacerbates disease intensity by trapping moisture and preventing rapid drying of foliage.

Management strategies must be integrated to minimize losses. Key practices include:

• Utilizing clean, certified, and fungicide-treated seeds.
• Implementing long-term crop rotation to break the pathogen's life cycle.
• Deep plowing to bury infected crop residues.
• Applying systemic fungicides at the onset of symptoms, particularly during early flowering stages.