Root rot: Generalities
The main cause of the root rot It is a fungus, the armillaria mellea. This fungus mainly attacks the arboreal plants and can be recognized by the appearance, under the bark, of creamy-white mycelium plaques with a characteristic fan shape; it can also occur on many ornamental plants, especially if they are not grown under suitable conditions. Generally the plants affected by root rot they show stunted growth, chlorotic leaves, weak branches and other symptoms, which often may initially be attributed to other diseases.
In the autumn months it is possible to manifest the appearance of fruiting bodies that manifest their presence (c.d. famigliole or small nails).
This pathogen is active for almost all months of the year, it mainly affects plants that are already weak or have lacerations on the trunk. It develops particularly in the presence of stagnant water and poorly drained soils.
The root rot can also be caused by other haptogens, such as phytium and thielaviopsis basicola, which cause the rot of the roots, which turn brown and develop, causing an evident state of suffering in the whole affected plant, which is no longer nourished from the roots themselves.
To avoid the onset of this disease it is therefore important to avoid stagnation of water (especially when the plant is at rest). If the plant has already been slightly affected, in the marginal areas remove and burn the affected branches and disinfect the trunk collar with copper-based products. If, on the other hand, the roots and the trunk are already severely compromised, it will be necessary to completely eradicate the plant to prevent the disease from spreading to nearby plants. Carefully disinfect the soil with sulfur-based products. On the market there are fungicides suitable for fighting root rot, but only if the infection is promptly treated and is not yet in an advanced stage of development.