Asterothyriaceae

The Asterothyriaceae family consists of a group of lichenized or semi-parasitic fungi belonging to the order Ostropales. In the field of plant pathology, these organisms are generally classified as epiphytic fungi that colonize the surfaces of leaves and stems of various vascular plants, primarily in tropical and subtropical climatic zones.

The disease is caused by microscopic ascomycetous fungi. They are characterized by the formation of specialized fruiting bodies known as apothecia, which develop directly on the leaf surface. By residing on the host, these fungi draw nutrients from the environment or from the metabolic by-products of the plant surface, potentially impacting host vitality.

A wide range of woody plants and shrubs, especially those with evergreen foliage, can be affected. The symptoms typically appear as small, dark spots or surface crusts that colonize the leaf blade, effectively blocking stomata and obstructing the plant's natural photosynthetic processes and gas exchange.

The development and dissemination of Asterothyriaceae are heavily influenced by environmental factors such as humidity and temperature. High relative humidity (often exceeding 80%) and shaded, sheltered environments are conducive to spore germination and the successful establishment of new colonies on healthy plant tissues.

The economic impact of this pathogen arises from the gradual decline in plant vigor, which can lead to premature leaf drop and reduced overall crop yield. Effective management includes:

• improving air circulation through strategic pruning;
• maintaining good canopy hygiene;
• the application of appropriate fungicide treatments to limit fungal surface growth when environmental conditions favor infection.