Phylogeny of Cryphonectria cubensis and allied species inferred from DNA analysis

Cryphonectria cubensis causes a serious canker disease of Eucalyptus in man y tropical areas of the world. The aim of this study was to determine the p hylogenetic relationships among strains of C. cubensis and the related spec ies C. parasitica, Endothia eugeniae and E. gyrosa using DNA sequence data. A second objective was to develop a rapid diagnostic method to distinguish among these taxa. The variable ITS1 and ITS2 regions, as well as the conse rved 5.8S gene of the rRNA operon, were amplified and sequenced, The amplif ied PCR products were also used in Alu I and Cfo I restriction digests. Ana lysis of the restriction profiles indicate that it is possible to distingui sh between C. cubensis, C. parasitica, E. eugeniae and E. gyrosa using RFLP s (restriction fragment length polymorphisms). This will facilitate the ide ntification of isolates thought to represent C. cubensis that sporulate poo rly in culture. Analysis of the sequence data showed that C, cubensis isola tes form a distinct clade that includes a strain from clove that might othe rwise have been assigned the name E. eugeniae, Isolates of C. parasitica fo rmed a separate clade. Endothia gyrosa grouped separately from both C. cube nsis and C. parasitica.