Paecilomyces infection

Paecilomyces infection is caused by fungi belonging to the genus Paecilomyces. While some species are known as entomopathogens utilized in biological control, others act as opportunistic plant pathogens that can compromise plant health, especially when the host is under abiotic stress.

This pathogen has a wide host range, frequently affecting vegetable crops, nursery seedlings, and stored agricultural products. It is particularly problematic in greenhouse environments where high humidity creates favorable conditions for the colonization of plant tissues by the fungus.

Symptoms of the disease typically include necrotic lesions on leaves and stems, as well as the appearance of white, pink, or brownish fungal mycelium on the surface of affected parts. Root infection results in tissue browning, decay, and subsequent wilting of the aerial parts of the plant.

Disease development is heavily influenced by environmental factors such as excessive soil moisture, high humidity, and poor ventilation. The fungus persists in organic debris and soil, spreading through conidia dispersed by water splashes, contaminated tools, or insect vectors present in the growing area.

The economic impact involves significant crop loss, reduced plant vigor, and potential pre-harvest decay. Control measures include:

• Proper sanitation of greenhouse surfaces and soil.
• Use of disease-free planting material.
• Implementing effective crop rotation.
• Monitoring humidity levels to prevent fungal growth.
• Applying targeted fungicides when initial symptoms appear.