Submitted to: FEMS Immunology and Medical Microbiology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 5/28/2005
Publication Date: 7/16/2005
Citation: Malkus, A., Reszka, E., Chang, C.J., Arseniuk, E., Ueng, P.P. 2005. B-tubulin gene in phaeosphaeria nodorum and p. avenaria. FEMS Immunology and Medical Microbiology. 249:49-56. Interpretive Summary: The Stagonospora blotch diseases in cereals are caused by two major fungal pathogens, Phaeosphaeria nodorum and P. avenaria. Identification of these fungal pathogens is based on spore shape and host specificity. Several molecular methods have been recently developed to provide accurate identification. In this study, we analyzed a new gene. Genetic variation in the gene made it possible to devise a quick and specific method to identify these fungal pathogens. The results will be of interest to scientists and diagnostics laboratories.
Technical Abstract: The full-length ß-tubulin gene (tubA) coding sequences were PCR-amplified and sequenced from two cereal Phaeosphaeria species, P. nodorum and P. avenaria, and the Phaeosphaeria species from rye (Secale cereale L.) and dallis grass (Paspalum dilatatum). A 1,556 bp tubA gene was found in wheat- and barley-biotype P. nodorum, P. avenaria f. sp. avenaria, homothallic P. avenaria f. sp. triticea (Pat1) and the Pat3 isolate from the State of Washington. Different lengths of the tubA gene were detected in two Pat2 isolates from foxtail barley (Hordeum jubatum L.), and the Phaeosphaeria spp. from dallis grass and Polish rye cultivars. The size difference was due to variation in the intron lengths in these three Phaeosphaeria species. The exon sequence was identical (1,344 bp) and encoded a 447 amino acid ß-tubulin. Like glyceraldehyde-3-phosphate dehydrogenase, the peptide sequence was identical in all Phaeosphaeria species used in this study, with the exception of the two Pat2 isolates. Six amino acid differences were evident in the ß-tubulin of these Pat2 isolates.