RESULTS OF TWO-YEARS EXPERIMENTAL TRIALS WITH NATURAL PRODUCTS AGAINST PLASMOPARA VITICOLA IN ORGANIC VITICULTURE

Summary

In organic farming the copper compounds are the only substances that can be used against
downy mildew. As the copper causes problems of environmental impact, the Regulation EC
n. 473/2002 fixed a ceiling on its use. Two-years experimental trials (2007-2008) were
carried out in organic vineyard in order to evaluate anti-downy mildew effectiveness of
natural products. Homeopathic products, resistance promoters, plant extracts and potassium
bicarbonate have been tested. In 2007, a year of limited infection pressure, these products
were able to control the disease, whereas in 2008, a year of high risk of disease, the natural
products were scarsely effective. In conclusion, the natural products can be used in
alternative to copper in condition of low or medium risk of infection, while, in conditions of
high infection pressure, it is possible to use the natural products in combination with copper
just to reduce the copper input