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The French vineyard is affected by three principal wood diseases: Eutypa dieback, esca and black dead arm (BDA). Phaeomoniella chlamydospora, Phaeocremonium aleophilum, Eutypa lata, Fomitiporia mediterranea, Diplodia seriata, Diplodia mutila and Neofusicoccum parvum are the main fungi isolated in France and associated with grapevine trunk diseases. The aim of this study was to highlight the type of wood lesions and the fungus present in the Alsace vineyards (France) and to compare it with those identified in the other french vine-growing regions or with the German vineyards. Therefore, we have studied two vineyards with two different grapevine varieties ('Auxerrois', 'Gewürztraminer'). The foliar symptoms showed that the plots planted with 'Auxerrois' and 'Gewürztraminer' varieties had respectively 12 and 21 % grapevines with symptoms in 2005. Different cross sections were made on trunks and arms of 55 vines showing foliar symptoms, totalizing 162 microbiological isolations. Visual characterisations of the different lesions were described. The isolations made from the different necrosis showed the presence of species of fungi involved in grapevine trunk diseases and other fungi. Microbiological observations showed that for the Auxerrois vineyard the majority of the vines were infected with D. seriata, P. chlamydospora, E. lata and F. mediterranea. In the Gewürztraminer vineyard, the fungus most frequently isolated was P. chlamydospora, followed by D. seriata. The presence of D. seriata in different parts of the grapevine wood and in young wood is related to the severe damages observed on the vegetation., VITIS - Journal of Grapevine Research, Vol. 49 No. 2 (2010): Vitis

This chapter presents the results of studies conducted to (i) detect and localize endophytic bacteria in symptomless and symptomatic leaf tissues of grapevine (Vitis vinifera) using fluorescence in situ hybridization (FISH) in combination with confocal laser scanning microscopy (CLSM); and (ii) test the antagonistic activity of Bacillus amyloliquefaciens AG1, previously isolated from grape wood affected by the esca syndrome, against grapevine fungal pathogens: Alternaria alternata, obtained from grapevine leaves showing necrotic concentric spots; Aspergillus carbonarius, A. ochraceus and Penicillium verrucosum, isolated from grapes affected by secondary rot; Botrytis cinerea, isolated from grapes with grey mould; Cladosporium viticola, agent of grapevine leaf spots; Fomitiporia mediterranea, obtained from grapevines with white rot symptoms; Fusarium oxysporum, isolated from the grapevine rhizosphere; Lasiodiplodia theobromae, isolated from vine wood with cortical cankers; Phaeoacremonium aleophilum and Phaeomoniella chlamydospora, both isolated from grapevine showing esca symptoms; Phoma glomerata from grape leaves showing necrotic spots; and Verticillium dahliae, obtained from decaying vine. The FISH/CLSM approach was successfully applied to visualize endophytic bacteria in grapevine leaves, including also those that it is not possible to cultivate in sterilized medium. Also, B. amyloliquefaciens AG1 showed a potential role as a biological control agent against trunk fungal pathogens as well as other fungal phytopathogens.