Cherry orchards can be attacked by various wood fungi and bacteria that, if not managed properly, produce wood diseases that can reduce productivity and even cause the death of plants.
Tavan Chile It helps us identify the main threats, their characteristics and how to handle them correctly.
- Bacterial cancer:
One of the most common diseases, and no less feared, is bacterial cancer. The bacteria pseudomona syringae It is the causal agent of this disease, also known as bacterial canker.
Unlike other threats, it is relatively easy to identify as there is more awareness about it.
Initially, it can be identified because it produces brown exudations or gummosis, which has a characteristic ferment-like smell. When the gummosis is removed from under the bark, a “wound” in the form of a crack can be observed from where the “gum” is secreted.
Another less visible characteristic during the recession period is the death of vegetative material, whether branches, twigs, shoots or the trees themselves. This can be identified by observing and making cuts in structures that look more dehydrated and have a less lively wood color.
“To ensure this, it is necessary to make a cut or remove material that may be affected. The branches usually break easily and, when observing the internal tissue, it already has a brown color, or green with brown tones. In turn, they usually have a fermenting smell characteristic of the disease, depending on the section in which the attack occurred and, therefore, the lack of sap irrigation due to the death of the conductive tissue,” explains José Ignacio Tagle, Zonal Centro Sur of Tavan Chile.
- 2. Cytopspora and Calosphaeria
These fungi are often confused with bacteria. Pseudomonas syringae, as they have very similar symptoms. However, unlike this bacteria, the exudations produced by the plant do not have a fermenting smell. Furthermore, when the “gum” comes off, cracked wounds are not observed.
However, just like with bacterial cancer, the wood begins to dehydrate, but in this case it becomes very soft, like a cork or a piece of rotten wood.
In the case of Cytospora, when looking under the bark of the affected branches, small spots or fruiting bodies known as "perithecia" or "spignidae" can be seen, which feed on the sap and cut off the passage of nutrients and water to the rest of the branches and to the tree in general.
"This disease, if not treated in time and with the appropriate tools, can be even more aggressive than bacterial cancer, even causing entire plants to dry out in a very short period of time, without giving a chance for palliative treatment," warns Tagle.
- 3. Silver
This well-known wood fungus is usually quickly identified, mainly by the cracking and peeling of the bark.
In some cases, dull-colored wood can be observed in the early stages of the disease.
This fungus also causes the death of branches, trunks and even trees. In extreme cases, its fruiting bodies known as “wood ears” can be observed during the autumn-winter season.
“Silvering becomes more prevalent during periods of vegetative activity, since the fungus installed in the wood produces a toxin that travels through the vascular bundles and is deposited on the leaves, leaving them a silvery colour,” explains Tagle. In cherry trees, this disease usually does not produce gummosis.
-Why is it important to keep gardens protected during this period?
-When plants enter dormancy, their metabolism and their ability to activate their defenses decrease considerably. At the same time, the most critical and susceptible moments for the entry of these diseases occur during this period, such as leaf fall, which causes natural wounds; frost, which causes microcracks; and the free movement of pathogens through water or high humidity.
-What does Tavan Chile's proposal for managing these threats consist of?
-Tavan Chile recommends the application of WERT + pH4 during leaf fall season. Then, the same application after 45 days, or on the date on which pruning is being carried out. And finish the winter treatment with an application before bud swells.
All these applications can be accompanied by synthetic fungicides without running the risk of incompatibility. In orchards that are severely affected, it is recommended to apply BACTOFUS + V6 + pH4 in spring and summer, depending on the condition of the garden.
-What are the advantages of applying this treatment?
–WERT, being a product specially designed to be incorporated into wood, having a long residual effect (+45 days) and not being washed away by rain, considerably reduces the possibility of these pathogens entering the plant. On the other hand, it has been shown that wood fungi do not respond to copper-based products, and that they can even be counterproductive if these pathogens are to be controlled.
For more information, you can visit our social networks @tavanlatam or call us at +56 9 42945384.
