Anhellia

Anhellia is a specific fungal disease that primarily affects tropical and subtropical woody plants. The pathogen is an ascomycete fungus that parasitizes living plant tissues, causing significant structural changes in the development of shoots and foliage. This disease is classified as a necrotic spotting type, as the pathogen destroys the epidermis and triggers the death of plant cells.

The main crops most susceptible to this disease include citrus species and various ornamental evergreen plants. The infection is most common in regions characterized by high humidity and stable moderate temperatures, which create an ideal environment for fungal spores to germinate on the surfaces of healthy plant tissues.

Symptoms of the infection manifest as dark, often slightly sunken spots on young branches and leaves. Over time, these spots expand, turning brown or nearly black, often surrounded by a chlorotic halo. In severe cases, the disease leads to premature leaf drop, twisting of young shoots, and overall stunting of the plant, which negatively impacts its growth and yield potential.

The spread and development of the infection are facilitated by prolonged rainfall, poor canopy aeration, and overcrowding of plantings. Fungal spores are disseminated by wind currents and rain splashes, easily infecting neighboring specimens. Furthermore, insect pests act as important vectors by creating mechanical wounds on the bark, allowing the mycelium to penetrate into healthy internal tissues.

Protection measures require a comprehensive approach, beginning with the sanitary pruning of affected branches. Additional methods include:

• Regular application of copper-based fungicides during the active growing season.
• Maintaining optimal planting distances to ensure proper air circulation within the canopy.
• Effective management and control of sap-sucking insect populations.
• Prompt removal and disposal of fallen leaves, which may serve as an overwintering site for fungal spores.