Pink disease

Pink disease is a destructive fungal condition caused by the pathogen Erythricium salmonicolor, a basidiomycete fungus. As a serious phytopathogen, it primarily attacks the bark and cambium of various woody plants. The fungus is taxonomically classified within the order Corticiales and is known for its ability to cause extensive necrosis in infected plant tissues.

The host range of Erythricium salmonicolor is quite broad, impacting economically vital crops such as rubber, citrus, cocoa, coffee, and tea. Initial symptoms often appear as a salmon-pink mycelial mat on the surface of branches and stems. As the infection progresses, the bark begins to crack, and underlying tissues die, eventually leading to the death of the distal parts of the branch.

The biology and lifecycle of the pathogen are highly dependent on moisture. The fungus produces basidiospores that are disseminated by wind, rain splashes, and sometimes insects. Upon landing on suitable surfaces, such as bark crevices or wounds, the spores germinate. The resulting mycelium penetrates the bark and colonizes the living tissue, effectively cutting off the plant's nutrient transport system.

Conditions favoring development include prolonged periods of high humidity and rainfall. In such environments, the fungus can proliferate rapidly, spreading across the canopy of a tree or between adjacent trees in a plantation. The virulence of the pathogen makes it a significant threat in tropical and humid temperate regions, leading to severe yield losses if not managed.

Management strategies must be integrated to be effective.

• Pruning and burning all infected branches to reduce inoculum density.
• Applying copper-based fungicides to protect healthy tissues from infection.
• Maintaining proper tree spacing to improve air circulation and reduce humidity within the canopy.
• Regular monitoring of plantation health to detect early stages of the pink-colored mycelial growth.