Root rot of the vine: identification
The root rots of the vine arise from the activity of some pathogens that attack the roots of vine plants. The micro-organisms responsible for this disease are fungi belonging to various species, such as the Armillaria (also called "chiodino"), Rosellinia necatrix (or "woolly rot"), Roesleria hypogaea and Phytophthora. The Arimillaria, in particular, is one of the most widespread species: in fact it has over forty different types all over the world. The fungi of these species prefer cold and wet areas and attack mainly live plants; in some cases, however, they also settle on dead wood. All species can act individually or can associate and give rise to multiple infectious processes extremely difficult to eradicate.
Damages produced on the plant
The fungal microorganisms that cause this problem act on the vital parts of the root causing their progressive deterioration. The fruiting bodies of the fungus attack the root structure of the plant and develop rapidly, especially during the autumn season. Two factors contribute to favoring the infectious process: the increase in the humidity rate due to the frequent rains and the intrinsic weakness of the plants weakened by the presence of a soil poor in nutrients. Facilitated by the humid climate, the fungus rapidly proliferates without the plant being able to offer adequate defenses: this causes its progressive drying up, since the roots, damaged by the disease, are no longer able to provide the plant with the nourishment it needs.
How to identify them
The presence of root rot is detectable through a symptomatology that affects both the roots and the aerial parts of the plant. The white mycelium with its woolly consistency is clearly visible on the root structure, easily extractable from the soil: the roots, which are very dark in color, give off a characteristic mushroom odor and present the bark raised at various points. The leaves of the plant, small and affected by chlorosis, tend to dry and break away early; the general appearance of the plant appears stunted, with the branches not properly lignified. The fruiting is insufficient, with small and scarce bunches. Over time, these symptoms are irreparably aggravated until the shrubs die.
How to combat root rot
The fight against root rot of the vine is particularly complex, especially in cases where the infectious process has already reached an advanced stage. At present, in fact, there are no chemical treatments capable of eradicating the disease definitively: the only effective strategy consists in an accurate work of prevention and control, with a continuous and careful examination of the health status of the new plants and the immediate elimination of the infected parts. To allow plants to develop an adequate defense system against pathogens it is very useful to enrich the soil with all the necessary nutrients through the use of fertilizers and fertilizers. To avoid contamination phenomena it is important to use only well-cleaned tools: often, in fact, the root rots of the vine are transmitted by the residues present on instruments previously used on infected soils.