The disease known as cherry leaf spot,anthracnose or cilindrosporiosis, is caused by the fungus Blumeriella jaapii. The application of treatments against anthracnose is essential, since the fungus greatly weakens the cherry tree and prevents the correct development of the fruit.
Blumeriella jaapii, attacks mainly cherry (Prunus cerasus) and cherry (Prunus avium), although it can be found in other trees of the Prunus genus.
Biological cycle
The anthracnose fungus spends winter feeding on the remains of organic matter (like a saprophytic fungus). During the spring, coinciding with the sprouting of the cherry tree, the fungus begins to emit conidia (spores) infecting the small buds.
Ascospores release spores for more than a month and a half. The spores are transported by wind and water to new areas of the crop.
When the leaves of the tree are wet for a period longer than 20 hours and the average temperature is more than 16 ° C, infection is very likely. The symptoms begin to be visible between 5 and 15 days after the infection, anticipating when temperature and humidity is high.
Secondary infections: whitish spots are visible that release Blumeriella jaapii spores when conditions permit.
Damages caused by Cherry leaf spot
In a market as eager for quality fruit as cherry. Damage caused by anthracnose, can make it unfeasible to pick cherries when treatments are not applied and the conditions are favorable. Taste and size of cherries are worsened and ripening becomes irregular.
Necrotic parts in the leaves that see reduced their photosynthetic capacity and negatively affect the vigor of the cherry tree. The affected leaves yellow and fall to the ground prematurely.
Stains on the peduncle of the cherries that dries ahead of time and worsens the appearance and post-harvest life of the cherry.
Control and treatments against anthracnose
Cultural measures
Focus on collecting and burning the leaves of infected trees, reducing inoculum. Burying the leaves also prevents fungal spores from spreading.
Treatments for Anthracnose
The recommended cupric treatments (in autumn after leaf fall and end of winter). They are ecological treatments that help reduce the presence of anthracnose latent.
Once pollination has finished (falling petals) it is essential to make a preventive treatment with fungicides.
Products authorized against Anthracnose on November 7, 2017:
Captan 47.5%: Belpron C-50, Capteran 50, Clorocarb-L, Merpan 47.5 SC and Capteran Flow. All of them with a security term of 21 days.
Captan 80%: Merpan 80 WDG, with 21 days of security. It controls the fungi that cause the following diseases of the cherry tree: dent, anthracnose, canker, hail wound healing, screening , monilia and mottled.
Dodina 40%: Syllit Flow, product with a 14 day security term.
Iprodiona 50%: Rovral Aquaflo, product with 14 days security term and also used against Monilia.
Tebuconazole 20%: Orius 20 EW and Orius 20 EW-N. They are products with 7 days of safety and suitable for the treatment of anthracnose and monilia.
Tebuconazole 25%: Folicur 25 WG and Folicur WG. Probably the best known products, with a safety term of 7 days.
Tiram 50%: Tirex Flow, Tiram Flow, Thisan 50 SC, Tisar-50 Flow, Thifit 50, Tiuram Flow and Deepest. They are broad spectrum products for the treatment of anthracnose, canker, screening, gnomonia , monilia and mottled.
Recommended Reading
Complete information on the following pests and diseases of the cherry tree :
Drosophila suzukii , San Jose Scale, Gomosis and Pulgón .
Warning
A significant part of the information, comes from Spanish research organizations. When phytosanitary products are used, it is important to verify that their use is currently authorized in the country of application.