LAUSR

We describe for the first time the fungus Diaporthe toxicodendri sp. nov., which causes canker disease on the stems and twigs of Toxicodendron vernicifluum. We conducted a phylogenetic analysis using combined multigene sequence data from the rDNA internal transcribed spacer sequence and partial genes for calmodulin, histone H3, beta-tubulin, and translation elongation factor 1-alpha. The results indicate that D. toxicodendri occupies a monophyletic clade with high support. Although 10 species are phylogenetically closely related to D. toxicodendri, morphological characteristics of size of alpha conidia and lacking of beta and gamma conidia support the distinction of this fungus from those closely related species. No sexual morphic structures have yet been found for the species. The pathogenicity of this species was confirmed by the inoculation test to T. vernicifluum.