Novel organic fungicides and elicitors
against downy mildew on grapevines were evaluated
on grapevine seedlings in a series of indoor screening
experiments under controlled conditions and, if they
have shown a good efficacy indoors, in a screening
vineyard under field conditions.
From 39 products tested under controlled conditions
10 were further examined under field conditions.
All of the new products tested under field conditions
showed at least partial efficacy. However, the efficacy
was not good enough to protect grapevine plants
sufficiently from downy mildew. For a complete replacement
of copper in plant protection against
downy mildew on grapevine in organic agriculture,
additional new products are needed.