Systematics of genus Gnomoniopsis (Gnomoniaceae, Diaporthales) based on a three gene phylogeny, host associations and morphology

Abstract

Species of Gnomoniopsis are leaf- and stem-inhabiting pyrenomycetes that infect plants in Fagaceae, Onagraceae and Rosaceae. Morphology and analyses of DNA sequences from three ribosomal DNA and protein coding regions, namely β-tubulin, translation elongation factor 1α (tef-1α) and the ITS region including ITS1, 5.8S rDNA and ITS2, were used to define species in Gnomoniopsis. Secondary structural alignment of the ITS region across four genera in Gnomoniaceae was used to increase the potential number of homologous positions in the ITS alignment. Ascospore isolates were grown from newly collected specimens. Type specimens were compared with these specimens to determine their identity. In this paper a recent concept of Gnomoniopsis is confirmed with phylogenetic resolution of additional species. Four new combinations and one new species are proposed. Nine species are described and illustrated, and a key is provided to the 13 species currently recognized in Gnomoniopsis.

• multilocus phylogeny
• oak anthracnose
• secondary structural alignment
• strawberry leaf blotch and petiole blight
• systematics

This research was conducted as part of a project financially supported by the National Science Foundation PEET (NSF PEET 03-28634). DMW thanks these individuals for their contribution to this project: Luis C. Mejía for his kind guidance; Marshall Bergen, Jo Anne Crouch, Karl Kjer and Lena Struwe for assistance at Rutgers University. In addition we thank Christian Feuillet for kindly providing the Latin description; Drew Minnis, Tunesha Phipps, and Sasha Allen at the Systematic Mycology and Microbiology Laboratory; Larissa Vassiljeva and Dimitar Stoykov for sending fresh collections from which cultures were obtained; Tobin Peever and Sonja Scheffer for presubmission comments on the manuscript, as well as the two anonymous reviewers for their constructive criticisms. We greatly appreciate the loan of specimens from the Agriculture and Agri-Food Institute, Ottawa, Ontario, Canada (DAOM), Berlin (B), Farlow Herbarium, Harvard University, Cambridge, MA (FH), the Botanical Museum, University of Helsinki, Finland (H), and the Swedish Museum of Natural History, Stockholm, Sweden (S).