PARENT SESSION
Poster Session #30: Disturbance Ecology II.
Tuesday, August 6. Presentation from 5:00 PM to 6:30 PM. Exhibit Hall B & C, TCC
169
Monitoring chestnut blight in Portugal - C. parasitica diversity in the "Serra de Sao Mamede" Natural Park.
Marcelino, José*,1, Bragança, Helena1, Grilo, Luís2, Luz, João Pedro3, Santos, Natércia1, 1 Estação Florestal Nacional Quinta do Marquês 2784-505, Oeiras, Portugal2 Parque Natural da Serra de São Mamede 7300-185, Portalegre, Portugal3 Escola Superior Agrária 6000, Castelo Branco, Portugal
ABSTRACT- This study has as its objective the development of a biological control program for chestnut blight in Portugal. We monitored 110 ha with chestnut (Castanea sativa) stands in the nationally important "Serra de Sao Mamede" Natural Park (PNSSM) which has the largest chestnut populations south of the Tagus River. It was verified that 36% of the sampled plots were affected by the disease and two new vegetative compatible (vc) types for Portugal were found. A total of four vc types were present in the PNSSM, reflecting the population diversity. From the obtained 43 isolates 66.6% belong to the most common vc type in Portugal, vc P 2 (incompatible with European vc types) and 33.4% are distributed among the remaining vc types. We can report an evolution tendency in the number of vc types in Portugal from four identified in 2000 to a total of six vc types present at 2001. The explanation for this evolution may be the occurrence of an endemic diversity pattern in the PNSSM. No hypovirulence has yet been found in Portugal.
KEY WORDS: Chestnut blight, Cryphonectria parasitica, Portugal, Serra de Sao Mamede