Marasmiellus troyanus

Marasmiellus troyanus is a basidiomycete fungus identified as the causative agent of a destructive root rot disease affecting banana plantations. While many fungi in the Marasmiellus genus are saprophytes, this specific species has evolved pathogenic capabilities that allow it to attack living plant tissue, particularly in the root zone and rhizome of susceptible host plants.

The primary host for this pathogen includes various cultivars of banana plants. The fungus colonizes the root system, infiltrating the vascular tissues and preventing the plant from absorbing water and nutrients effectively. This leads to systemic stress, severely compromising the plant's ability to produce quality fruit and maintain healthy vegetative growth.

Symptoms of the infection typically include necrotic lesions on the roots, which eventually lead to root system decay. As the disease progresses, the above-ground parts of the plant exhibit chlorosis (yellowing), wilting, and stunted growth. In humid conditions, mycelial mats may develop at the base of the pseudostem, and small, white, mushroom-like fruiting bodies may appear, indicating the presence of the pathogen.

The development and spread of Marasmiellus troyanus are highly favored by environmental conditions such as high soil moisture and poor soil aeration. Stagnant water around the base of the plant creates a conducive environment for the fungus to spread through the soil and infect adjacent healthy roots. Furthermore, contaminated tools and human activity can accelerate the movement of spores across the field.

Management of this disease relies on integrated crop management strategies:

• Sourcing disease-free planting material from reputable nurseries.
• Improving field drainage to prevent waterlogging around the root zone.
• Implementing regular field inspections to identify and remove symptomatic plants.
• Applying preventive fungicides in highly infested zones.
• Practicing strict hygiene when handling tools used in areas with known infection.