Endophytic Fungi in Asymptomatic Vitis vinifera L. and their Effects on Plasmopara viticola

During a multi-year study on the life cycle of Plasmopara viticola to assess the typical epidemiology of downy mildew on grapevine (Vitis vinifera) in west Sicily (Italy), several leaves on which the downy mildew had collapsed were found and observed in a vineyard located in Marsala, in Trapani Province. An antagonistic fungus was isolated from these leaves and named A20; through its morphology, it was identified as a hyphomycete belonging to the genus Acremonium. The antagonism of A20 against the asexual and sexual spores of P. viticola, as well as endophytic nature of the genus Acremonium in V. vinifera were confirmed by further studies which have been carried out over the past decade. In order to inform winegrowers about this new future possibility for the biological control of grapevine downy mildew, this chapter reports the results of investigations on the interaction between the endophytic fungus A20, the presence of endophytic fungi in the grapevine and downy mildew