Calonectria indusiata

Calonectria indusiata is a pathogenic fungus that causes severe damage to various plant species. It is known as a significant threat in nurseries and forest plantations, particularly affecting broad-leaved trees where high humidity and temperature levels facilitate its rapid progression.

The host range of this pathogen primarily includes species of the genus Eucalyptus. However, it can also infect other woody ornamental plants. The presence of the pathogen is often associated with nursery-grown seedlings, where it causes damping-off, root rot, and shoot blight, leading to significant plant mortality.

Symptoms are multifaceted and include the development of necrotic lesions on leaves and stems, wilting of terminal shoots, and decay of the root system. Under moist conditions, the pathogen produces characteristic conidia that appear as a fine, white, or cream-colored growth on infected tissue surfaces.

The fungus thrives in environments with high rainfall or overhead irrigation and warm temperatures. It spreads via contaminated soil, infected plant debris, and water splash, making it highly contagious within confined cultivation spaces like greenhouses or nursery beds where plant density is elevated.

Integrated management is essential for controlling Calonectria indusiata. Control strategies include:

• Utilizing disease-free propagation material and sterile growing media.
• Improving greenhouse ventilation to reduce leaf wetness duration.
• Implementing strict sanitation protocols to remove and destroy infected plant debris.
• Applying preventive fungicide treatments when environmental conditions favor disease outbreak.