Powdery mildew: what it is, how it develops, and how to effectively eliminate it from fruit

• Maintain good ventilation in the crop to reduce the duration of favorable conditions around the fruit.

• Avoid excessive plant density and carry out pruning or other necessary interventions to improve air circulation.

• Avoid excessive shading, especially in crops with very dense vegetation.

• Frequently monitor the fruit to detect the first whitish colonies before the disease spreads.

• Remove and dispose of severely affected tissues and fruit, when feasible, to reduce the amount of available inoculum.

• Avoid excessive nitrogen fertilization, as excessively tender vegetative growth can favor the establishment and development of powdery mildew.

• Maintain balanced plant nutrition, avoiding imbalances that increase tissue susceptibility.

• Use varieties or cultivars with tolerance or resistance to powdery mildew when available.

• Avoid creating excessively favorable microclimates through improper vegetation management.

• Apply preventative treatments to crops and during historically favorable periods when there is a high risk of infection.

• Begin phytosanitary control at the first sign of infection and do not wait for colonies to cover a large area.

• Alternate active ingredients belonging to different action groups to reduce selection pressure on the pathogen.

• Do not make repeated applications of products with the same mechanism of action when effective alternatives exist.

• Respect the doses, intervals, and application conditions indicated on the label of each authorized product.

• Combine, when permitted and technically appropriate, fungicides with different modes of action with multi-site products.

• Avoid unnecessary treatments when there is no real risk of infection, thus reducing the pathogen's exposure to fungicides.

• Alternate chemical applications with cultural practices and other available control tools.

• Remove infected plant debris when it could constitute a source of inoculum for the next crop.

• Control weeds that may act as a reservoir for the pathogen when they are susceptible and located near the crop.

• Pay special attention to periods with moderate temperatures and environmental conditions favorable for the production and dispersal of conidia.

• Periodically review the effectiveness of applied treatments and detect any loss of susceptibility in the pathogen.

• Integrate preventive, cultural, varietal, and phytosanitary measures into an integrated pest management strategy instead of relying exclusively on fungicides.

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