Phylogeny of the rust fungi: an approach using nuclear large subunit ribosomal DNA sequences

Abstract

Sequence data from nuclear large subunit ribosomal DNA was used to infer phylogenetic relationships of selected genera of the Uredinales. We investigated 52 rust fungi representing nine families and three outgroup species. Neighbor joining analysis and a Bayesian method of phylogenetic inference using Monte Carlo Markov chains confirm the rust fungi as a natural group and indicate that Puccinia, Uromyces, Endophyllum, and Cumminsiella have a common origin. The autoecious Rosaceae-rusts Phragmidium, Kuehneola, Triphragmium, and Trachyspora are a monophyletic group. The gasteroid genus Ochropsora is closely related to Tranzschelia. While the Pucciniastreae sensu Dietel (1938) is recognized as a monophyletic group in neighbor joining analysis, the Pucciniaceae s.l. (Dietel 1928) is supported by Bayesian analysis. The following genera appear to be monophyletic: Chrysomyxa, Coleosporium, Cronartium, Gymnosporangium, Melampsora, Phragmidium, and Tranzschelia, whereas the genera Puccinia, Pucciniastrum, Thekopsora, and Uromyces are not.Key words: molecular phylogeny, systematics, nuclear large subunit rDNA, Basidiomycota, Urediniomycetes, Uredinales.