Submitted to: Mycological Symposium Asian Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 9/17/2001
Publication Date: N/A
Technical Abstract: Ribosomal internal transcribed spacers (ITS1, 5.8S rRNA gene and ITS2) were PCR-amplified and sequenced from herbarium specimens of different graminicolous Puccinia species. These sequences were aligned with the profile mode of Clustal X. Phylogenetic analyses were performed using the neighbor-joining (NJ) algorithm with the Draw N-J Tree option of Clustal X. .Phylogenetic analysis based on the ITS sequence data indicated that Puccinia hordei sensu lato is a complex species. We recognized three taxa within this complex species: P. hordei sensu stricto on Hordeum vulgare; P. holcina on Lolium temulentum, Lophochloa phleoides and Trisetum flavescens; and P. sp. on Taeniatherum asperum. In the P. recondita species complex we also recognized different taxa as follows: P. recondita s.s. on Secale segetale and Elymus sp.; P. bromina on Bromus Bromus spp.; P. persistens ssp. triticina (wheat leaf rust) on Triticum aestivum and Aegilops taushii; and P. persistens ssp. agropyri on Elymus hispidus. Our phylogenetic analysis showed P. recondita s.s. is more closely related to P. hordei s.l., than to P. persistens. ITS sequences of leaf rust from Triticum aestivum and leaf rust on Aegilops taushii were identical, which supports the idea that leaf rust collections from wheat could infect Aegilops species. On the basis of this analysis, variation also was observed among specimens of P. striiformis from wheat, Dactylis glomerata and Poa pratensis. This result agrees with a previous study on isozyme phenotypes of yellow rust from these hosts. The taxonomic implication of these results is that populations of P. striiformis on the above-mentioned hosts should be considered as different taxa at least at the infraspecific level.