Deuterophoma tracheiphila

Deuterophoma tracheiphila is a phytopathogenic fungus that causes a disease known as Mal secco in citrus trees. This disease is particularly devastating to lemon trees, but can also affect other citrus species. The fungus is native to the Mediterranean region and has been a significant problem for citrus growers in this area for many years.

Description

Deuterophoma tracheiphila is a ascomycete fungus. It produces conidia, or asexual spores, which are spread by wind and rain. These spores can infect citrus trees through wounds or natural openings, such as stomata. Once inside the tree, the fungus grows in the xylem, causing a blockage that prevents water and nutrients from being transported properly. This leads to wilting, yellowing, and eventually death of the tree.

Symptoms and Diagnosis

The symptoms of Mal secco disease include wilting, yellowing, and leaf drop. The disease progresses from the top of the tree downwards, and infected branches often die back. In severe cases, the entire tree may die. Diagnosis is usually based on these symptoms, but can be confirmed by isolating the fungus from infected tissue and identifying it under a microscope.

Management and Control

Management of Deuterophoma tracheiphila involves a combination of cultural practices and chemical control. Infected trees should be removed and destroyed to prevent the spread of the fungus. Pruning tools should be disinfected between trees to avoid transferring the fungus. Fungicides can also be used to protect healthy trees from infection.

Impact

Mal secco disease has a significant impact on citrus production in the Mediterranean region. It can cause substantial yield losses and even kill mature trees. This not only affects the livelihoods of citrus growers, but also the availability of citrus fruits for consumers.

See Also

• Citrus
• Phytopathology
• Fungus
• Ascomycota