Coffee tracheomycosis

The disease is caused by the fungus Fusarium xylarioides (teleomorph: Gibberella xylarioides). This pathogen acts as a vascular wilt agent, infecting the xylem of coffee trees. By colonizing the conductive tissue, the fungus prevents water and nutrient transport, leading to the rapid decline and eventual death of the affected plant.

The primary host for this pathogen is the coffee plant (genus Coffea), specifically affecting C. arabica and C. canephora. The infection is particularly devastating in African coffee-growing regions, where it impacts trees across various stages of development, from young nursery seedlings to mature, productive trees in field conditions.

Early symptoms include yellowing and leaf curling, which eventually lead to dieback and leaf shed. As the disease progresses, the bark on stems and branches shows dark necrotic lesions, often turning black. Internally, the woody tissues exhibit a brown or black discoloration, which is a diagnostic indicator of the vascular blockage caused by the fungal infection.

Environmental conditions such as high humidity and rainfall facilitate the dispersal of fungal spores. Furthermore, human activity is a major driver of spread; contaminated pruning equipment, saws, and knives are primary vectors for transmitting the pathogen from diseased trees to healthy ones. Damage to the tree bark during routine cultivation practices creates entry points for the fungus.

The economic impact of Fusarium xylarioides is severe, as it causes systemic infection that is almost impossible to cure. Once a tree shows clear symptoms, it serves as a source of inoculum for the entire plantation. Consequently, integrated pest management focused on rigorous sanitation and the use of resistant germplasm is essential for the sustainability of coffee production.

• Implementation of strict quarantine measures for coffee seedlings.
• Regular sterilization of pruning tools with appropriate disinfectants.
• Immediate uprooting and burning of infected trees to reduce inoculum pressure.
• Selection and breeding of coffee varieties with proven resistance.
• Monitoring plantation health and ensuring balanced plant nutrition.