Fungi Associated with Esca and Grapevine Declines in North Ribatejo, Portugal M.R. Mendes (1), J.P. Luz (1), E. Diogo (2) & A. Carvalho (2) (1) Escola Superior Agrária de Castelo Branco, Qt.ª Sr.ª Mércules, Castelo Branco, Portugal; (2) Direcção Geral de Protecção das Culturas, Tapada da Ajuda, Ed. 1, Lisboa, Portugal Abstract A survey of 179 vineyards in eight municipalities of North Ribatejo, Portugal, namely Abrantes, Almeirim, Alpiarça, Chamusca, Golegã, Santarém, Tomar, and Torres Novas was conducted in 2002 to identify pathogenic wood fungi. Grapevines showing esca and decline symptoms were examined for the presence of pathogenic fungi. Slightly less than half of the vineyards (46.4%) showed symptoms of grapevine decline. Eighteen phytopathogenic fungi were isolated from the wood of the grapevines with decline symptoms. The isolates were identified according to their morphological characteristics on PDA. The fungi isolated and the percentage of the vineyards affected were: Phaeoacremonium spp. (22.9%), Phaeomoniella chlamydospora (20.5%), Phomopsis viticola (18.1%), Phoma sp. (14.5%), Penicillium sp. (10.8%), Sphaeropsis sp. (8.4%), Seimatosporium sp. (7.2%), Alternaria sp. (6.0%), Acremonium sp. (4.8%), Conyothyrium sp. (4.8%), Truncatella sp. (4.8%), Cladosporium sp. (3.6%), Aureobasidium sp. (2.4%), Fusarium sp. (2.4%), Arthrinium sp. (1.2%), Fomitiporia punctata (1.2%), Pestalotiopsis sp. (1.2%), and Phytophthora sp. (1.2%). The spatial distribution of the fungi in North Ribatejo is presented and discussed. Introduction The Petri disease and other grapevine declines have been causing a considerable destruction of grapevines in Portugal. The species of Phaeomoniella and Phaeoacremonium associated with these declines were first detected in central and southern Portugal by Rego et al. (2000) and in the Vinho Verde region (northwest Portugal) by Chicau et al. (2000). Research on the aetiology of esca suggest that different pathogens are probably involved. Recently, it has further been suggested that different fungi, causing at least two different diseases (esca and Petri disease), can cause similar symptoms on grapevine (Surico and Mugnai, 2001). The fungi associated with grapevine decline in northwest Ribatejo, along the Tagus river valley, and the spatial distribution of the fungi associated are presented in this work. Materials and Methods The grapevine decline was surveyed in 179 vineyards of different ages and 197 trunks were colected from symptomatic vines. Fungi were isolated by transferring small pieces of wood tissue from different types of necrosis to plates of PDA (Merck). Cultures were incubated at 25ºC in the dark for about 7 days. Isolates were transferred to PDA, incubated at room temperature and identified according to their morphological characteristics. Identifications were made from squash mounts of fruiting structures mounted in lactophenol. References Rego, C., Oliveira, H., Carvalho, A. & Philips, A. (2000). Involvement of Phaeoacremonium spp. and Cylindrocarpon destructans with grapevine decline in Portugal. Phytopathologia Mediterranea, 39: Chicau, G., Aboim-Inglez, M., Cabral, S. & Cabral, J.P.S. (2000). Phaeoacremonium chlamydosporum and Phaeoacremonium angustius associated with esca and grapevine declina in Vinho Verde grapevines in Northwest Portugal. Phytopathologia Mediterranea, 39: Surico, G. & Mugnai, L. (2001). Sulla presenza di venature brune nella vite: il caso delle barbatelle e il ruolo di Phaeomoniella chlamydospora. Informatore Fitopatologico, 51: Results and Discussion The results of the percentage of fungi detected in trunks associated with grapevine decline symptoms are shown in Figure 1. The main results are the following:  Phaeoacremonium spp. was the most frequently isolated fungi (22.9%), being isolated nine times as the only fungi present, six times associated with Phaeomoniella chlamydospora, other six with Phomopsis viticola, and one with Acremonium sp.  Phaeomoniella chlamydospora was the second most isolated fungi (20.5%), being seven times isolated alone, six associated with Phaeoacremonium spp., and five with Phomopsis viticola.  Phomopsis viticola was the third most isolated fungi (18.1%), being six times isolated alone, other six associated with Phaeoacremonium spp., and five times with Phaeomoniella chlamydospora.  Acremonium sp. was isolated four times (4.8%), three alone and one associated with Phaeoacremonium sp.  Fomitiporia punctata was isolated only once (1.2%) and it was not possible to detect other fungi associated. The spatial distribution of the fungi detected in grapevine trunks with decline symptoms can be seen in Figure 2. The results show that:  Phaeoacremonium spp., Phaeomoniella chlamydospora and Phomopsis viticola are the fungi with highest incidence and have a more regular spatial distribution in the areas surveyed;  The Phaeoacremonium spp. + Phompsis viticola association appears only in the left bank of Tagus River, probably because that area is frequently flooded;  Phaeomoniella chlamydospora and Phaeoacremonium spp. are commonly found alone and in association with other fungi, mainly together or with Phomopsis viticola;  Acremonium sp. was only found alone in the north of the surveyed area. Figure 1 – Percentage of fungi detected in grapevine trunks with decline symptoms in Ribatejo Vineyards. Figure 2 – Distribution of the isolated fungi in the Northwest Ribatejo region. LISBON