Citrus Anthracnose: Symptoms, Prevention and Treatment

Anthracnose is a severe fungal disease that affects various citrus species. Caused by several fungi of the genus Colletotrichum , including Colletotrichum acutatum , it can significantly reduce fruit production. At Agrumiverse , as a citrus plant supplier and citrus plant wholesaler , we help citrus growers prevent this disease with proven solutions and personalized technical advice.

Symptoms of Anthracnose

Symptoms of anthracnose depend on the part of the tree affected. They can appear on leaves, fruit, and young shoots. The most common signs are:

On the leaves:

• Brown spots: Light brown circular spots with purple edges appear on the leaves. In advanced stages, tiny black spots (fruiting bodies of the fungus) may form.

On fruits:

• Brown to black spots: The fruit has spots 1.5 mm in diameter. These spots are a sign of dry rot developing inside the fruit.
• Spore Clusters: Under humid conditions, salmon-pink spores may appear on lesions.
• Dark necrosis: The skin of the fruit can develop dark necrosis which compromises its commercial quality.

On young shoots:

• Lesions: Lesions appear on young shoots, causing the twigs to dry out and the branches to gradually die back from the tips.

Citrus Species Affected by Anthracnose

Anthracnose can affect all citrus species. However, the severity of the infection depends on climatic conditions, cultural practices and the natural resistance of each variety. At Agrumiverse , as a citrus specialist and technical advisor in citrus cultivation , we offer varieties selected for their disease tolerance.

Anthracnose Prevention

Prevention is crucial in controlling citrus anthracnose. Here are some measures recommended by Agrumiverse , your partner in wholesale citrus plants :

• Winter treatment: Apply a copper-based product (e.g. Naturam 5) at a rate of 2.5 kg/ha to reduce overwintering forms of the fungus.
• Pruning: Prune regularly to aerate the tree and remove infected twigs and shoots. This reduces stagnant moisture, a factor in the spread of the fungus.
• Debris Management: Collect and dispose of pruning debris, fallen fruit, and dead leaves that can be sources of infection.
• Weeding: Ensure good weeding to eliminate weeds that may harbor fungal spores.
• Insect Control: Control insects and mites that can cause injury to fruit, providing entry points for the fungus.
• Drainage: Ensure good soil drainage to avoid water accumulation which encourages the development of the disease.

Treatment of Anthracnose

Chemical and biological treatments can help manage anthracnose. Here are some recommendations:

Chemical treatments:

• Flowering-Fruit Set: Use Score fungicide at a dose of 0.2 L/ha.
• Fruit enlargement: Apply Priori Opti at a rate of 1.5 L/ha.

Alternative methods:

• Onion and Garlic Extracts: Use preparations made from onion and garlic extracts, which are rich in sulfur compounds, to inhibit the growth of the fungus.
• Purins and natural infusions: Apply purins (nettle, comfrey) or natural infusions to strengthen the immune defenses of your citrus fruits.

Important Points to Remember

• Serious Disease: Anthracnose can affect all parts of the tree, significantly reducing the quality and quantity of fruit production.
• Importance of prevention: Effective prevention, combined with appropriate treatments, is essential to limit economic losses due to this disease.
• Integrated approach: For optimal control, combine preventive measures, chemical treatments and alternative methods. At Agrumiverse , as a supplier for professional citrus growers , we offer technical support to adopt a complete and integrated management strategy.

FAQ

What are the main symptoms of citrus anthracnose?

The main symptoms include brown to black spots on leaves and fruits, lesions on young shoots, and progressive dieback of twigs.

How to prevent anthracnose?

Prevention includes regular tree pruning, removal of plant debris, moisture management through good drainage, and the use of copper-based winter treatments. Agrumiverse also recommends regular monitoring of orchards to detect symptoms early.

Which citrus fruits are most vulnerable to anthracnose?

Anthracnose can affect all citrus species, but its impact varies depending on climatic conditions and cultivation practices. Some varieties selected by Agrumiverse have greater resistance.

What are the alternative methods of treating anthracnose?

In addition to chemical treatments, alternative methods such as onion and garlic extracts, as well as nettle or comfrey manures, can strengthen the trees' natural defenses and limit the progression of the disease.

Why is it important to treat anthracnose quickly?

Anthracnose can cause significant losses in terms of production and fruit quality. Early detection and appropriate treatment can limit the spread of the disease and prevent more serious damage.

How can Agrumiverse help you fight anthracnose?

Agrumiverse , as a citrus growing specialist , provides high-quality, disease-resistant citrus plants and offers personalized technical advice for optimal management of your orchards.