Pathogenicity of Fusarium spp., Cylindrocarpon sp. and Diplodina sp. on grape roots

• Author(s): Gugino, B.; Stewart, E.; Travis, James;
• Abstract: Mature grapevine decline is an increasingly serious problem for vineyards in Pennsylvania. The symptoms of decline, which typically appear when the vine is between four and seven years old, include reduced shoot growth, sparse yellow foliage, reduced yield and necrosis and stunting of the roots. Grapevines declining from fungal pathogen infection also produce a reduced crop of inferior fruit. During the summer of 1999, six Pennsylvania vineyards were assayed for potential fungal pathogens associated with declining vines. Fusarium equiseti, F. oxysporum, F. solani, F. sporotrichiodies, Cylindrocarpon destructans, and a Diplodina sp., were isolated from the roots of several declining own-rooted French-hybrid grapevines. This study evaluated the pathogenicity of these fungal pathogens on grape roots. The roots of hardwood grape cuttings of Vitis labrusca cv. Concord and two roostocks, Riparia and Couderc 3309, were pruned and root dip inoculated with a conidial suspension (106 spores/ml) for 30 minutes. The vines (10 per fungal isolate per cultivar/rootstock) where grown in a greenhouse before being evaluated for root disease severity and the root and shoot dry weights. The roots of three vines were plated on potato dextrose agar for re-isolation of the fungus. Grape root infection by Fusarium spp., Cylindrocarpon sp. and Diplodina sp. was determined.
• Publication Date: Jun 2001
• Journal: Phytopathology