Ectophoma blight

The causative agent of Ectophoma blight is the fungus Ectophoma multirostrata. This pathogen belongs to the coelomycetes group and is known for causing localized necrotic lesions on various parts of host plants. The fungus survives primarily as pycnidia in infected plant debris or in the soil, acting as a primary source of inoculum for the next growing season.

This pathogen has a wide host range, affecting various botanical families, including vegetables, medicinal plants, and ornamental shrubs. Ectophoma multirostrata is frequently reported in both glasshouse and open-field conditions, where it exploits favorable climatic periods to colonize its hosts and disrupt normal physiological functions.

Symptoms of the infection usually appear as distinct spots or blotches on leaves, petioles, and stems. These lesions are typically brown or dark, often surrounded by a chlorotic halo. As the disease progresses, the central part of the lesion becomes dotted with small, black pycnidia, which are the fruiting bodies of the fungus. Premature leaf drop and stunted growth are common outcomes of severe infection.

Environmental conditions play a critical role in the development and spread of Ectophoma multirostrata. High relative humidity and moderate temperatures between 20°C and 25°C provide the ideal environment for conidia germination and colonization. Rain splash or overhead irrigation systems are the primary drivers for the short-distance spread of spores within a field or greenhouse.

The impact of this disease can be significant, leading to reduced photosynthetic area and market value of the produce. Management strategies should focus on an integrated approach to minimize fungal pressure:

• implementing strict crop rotation cycles;
• removing and destroying infected plant material promptly;
• improving air circulation in greenhouse environments;
• applying appropriate fungicides when environmental conditions favor disease outbreaks.