Morphological and molecular characterisation of Campylocarpon and Cylindrocarpon spp. associated with black foot disease of grapevines in Uruguay

Black foot disease of grapevines is a problem in most grape-producing regions of the world. This disease affects both young and mature plants, which show retarded growth and eventually die. Species of Cylindrocarpon have been identified as the causal agent of this disease. Fungal isolates were obtained from roots of symptomatic plants and plantlets from commercial vineyards in Uruguay. Morphological characteristics on malt extract agar were recorded, and DNA purified. Internal transcribed spacer (ITS) rDNA was amplified with primers ITS 4 and ITS 5 and the amplified fragments were sequenced. Phylogenetic analyses were done with sequences from Uruguay and sequences from GenBank using PAUP* (Phylogenetic Analysis Using Parsimony). Six phylogenetic groups were found that matched six previously known taxa. These groups were supported by morphological characteristics. Isolates were assignable to Campylocarpon and Cylindrocarpon species. Ca. pseudofasciculare , C. destructans var. crassum , C. liriodendri , C. macrodydimum , C. olidum var. crassum and C. pauciseptatum represent new records for Uruguay. This work is the first step towards a better understanding and management of black foot disease in local conditions.