Pea blight

Pea blight is a fungal disease caused by the pathogen Ascochyta pisi, a member of the Sphaeropsidales order. This infection poses a significant threat to agricultural production, as it affects the foliage, stems, and pods of pea plants, resulting in reduced yield and compromised seed quality.

While the primary host is the field pea, the fungus is known to infect a variety of other pulse crops, including vetch and chickpeas. The pathogen survives in crop debris and soil as pycnidia and mycelium, and is frequently introduced into new areas through infected seeds, acting as the primary source of initial outbreaks.

Symptoms are characterized by the appearance of round, sunken lesions with dark margins on leaves and stems. As the infection progresses, small black dots representing the pycnidia appear within these spots. In severe cases, the lesions spread to the pods, infecting the developing seeds and causing necrosis of plant tissue.

Development and spread of the disease are heavily favored by high humidity and moderate temperatures. Rain-splashed spores (conidia) are the primary mechanism for transmission between plants. Frequent periods of wet weather during the flowering and pod-filling stages create ideal conditions for the rapid multiplication of Ascochyta pisi.

Effective management requires a multi-faceted approach, including the use of certified disease-free seeds and the implementation of a strict crop rotation program. Incorporating resistant varieties and deep-plowing crop residues help to minimize the inoculum levels in the soil, while chemical control involves targeted fungicide applications during periods of high disease risk.

• Seed treatment with appropriate fungicides.
• Long-term crop rotation cycles.
• Deep incorporation of infected plant residues.
• Scouting and timely foliar fungicide application.