Botrytis in grapevine is one of the most important fungal diseases in vineyards worldwide. This pathogen, caused by the fungus Botrytis cinerea, can lead to significant losses in both yield and grape quality when environmental conditions favour its development.
Commonly known as grey mould, this disease primarily affects grape clusters, although it can also appear on leaves, flowers or shoots under certain conditions. In vineyards destined for wine production or table grape, the presence of Botrytis can reduce crop yield and alter fruit quality.
Understanding how the disease develops, what factors favour its appearance, and what prevention strategies can be applied is essential to maintaining vineyard health. In this article we analyse the main aspects of Botrytis cinerea in grapevine and the agronomic practices that can reduce its impact on the crop.
What is Botrytis cinerea
The causal agent of Botrytis in grapevine is the fungus Botrytis cinerea, a widespread pathogen capable of infecting more than two hundred different plant species. In the case of grapevine, this fungus develops primarily on grape clusters, where it causes the degradation of fruit tissue.
The pathogen produces fungal spores that can spread easily through wind, water, or even through the activity of insects and agricultural work. When these spores come into contact with susceptible plant tissue and humidity conditions are adequate, they can germinate and begin the infection process.
One of the key characteristics of Botrytis cinerea is its ability to remain latent in the crop. This means that infection can occur in the early stages of the vineyard cycle, but visible symptoms may appear later, when the fruit is close to ripening.
Importance of Botrytis in the vineyard
Grey mould in grapevine is particularly concerning in areas where climatic conditions favour prolonged periods of humidity during cluster development. In these situations, the pathogen can develop rapidly and affect a significant portion of the production.
The consequences of Botrytis in grape can be varied. First, the disease causes the degradation of grape berries, which lose firmness and become soft. This process reduces the commercial yield of the crop and can make harvesting more difficult.
Second, the presence of the fungus can affect the quality of grapes destined for winemaking. The development of the pathogen can alter the composition of the must, modifying the balance between sugars, acids and aromatic compounds.
In the case of table grapes, the impact can be even greater, since the appearance of rot in the clusters directly reduces the commercial quality of the product.
Symptoms of Botrytis in grape
The symptoms of Botrytis cinerea in grapevine are observed mainly in the clusters, especially during the final stages of fruit development.
One of the first signs of the disease is the appearance of small brown spots on the grape berries. These spots can spread rapidly and cause softening of the fruit tissue.
As the infection progresses, the affected berries may become covered with a characteristic greyish mycelium, formed by the growth of the fungus and spore production.
- Brown spots on the berries
- Softening of the fruit
- Appearance of grey mycelium
- Dehydration of the cluster
- General deterioration of the fruit
When pathogen pressure is high, the disease can spread rapidly within the cluster, affecting a large number of berries.
Factors that favour the appearance of Botrytis
The development of Botrytis in grapevine is closely related to the environmental conditions present in the vineyard. The combination of high humidity and moderate temperatures creates a favourable environment for the germination of fungal spores.
Rainfall during cluster development or in phases close to harvest can significantly increase the risk of infection.
- High ambient humidity
- Frequent rainfall during the crop cycle
- Insufficient ventilation in the vineyard
- High vegetation density
- Wounds on berries caused by insects or hail
Wounds on the fruit are particularly problematic, as they facilitate the penetration of the pathogen into grape tissue.
Vineyard cycle stages with the highest risk
Flowering
During flowering, the reproductive structures of the grapevine can be colonised by the pathogen if humidity conditions coincide.
Fruit set
In this initial stage of cluster development, the presence of water on plant tissue can favour the germination of spores.
Ripening
Cluster ripening is one of the most critical moments for the appearance of grey mould in grapevine. The grape berries become more susceptible to infection and the pathogen can develop rapidly if humidity is present.
Agronomic strategies to prevent Botrytis
Vineyard management plays a fundamental role in the prevention of Botrytis in grapevine. Certain agronomic practices can help reduce the conditions that favour pathogen development.
- Canopy management to improve ventilation
- Reduction of humidity inside the vegetation
- Removal of infected plant material
- Adequate irrigation management
- Monitoring of climatic conditions
These practices help create a less favourable environment for fungal development and reduce disease pressure.
Biological control of Botrytis in the vineyard
In recent years, biological control in agriculture has gained importance within plant protection programmes. This approach is based on the use of beneficial organisms capable of competing with pathogens and limiting their development.
In the case of Botrytis in grapevine, the use of beneficial microorganisms can help reduce the capacity of the pathogen to establish itself on the plant surface.
Some bacteria and fungi present in the agricultural environment can colonise plant tissue and compete with Botrytis cinerea for space and nutrients.
Beneficial microorganisms in vineyard management
- Competition for space and nutrients
- Production of antifungal metabolites
- Stimulation of the plant’s natural defences
Through these mechanisms, beneficial microorganisms can contribute to limiting the development of fungal pathogens in the crop.
Agricultural microbiology and biocontrol solutions
Research in agricultural microbiology has led to the development of innovative biocontrol solutions based on microorganisms that help protect crops against diseases.
These products, known as microbiological biofungicides, are increasingly being integrated into integrated disease management programmes.
At Veganic, we work on the development of microbiological solutions designed to strengthen crop protection against fungal pathogens such as Botrytis cinerea. We are driving a new generation of biocontrol that is more effective, sustainable and aligned with the agriculture of the future. Now is the time to take the step towards smarter, more conscious farming.
