Location: Cereal Disease LabTitle: Molecular phylogenetic relationships of the brown leaf rust fungi on wheat, rye and other grasses Author
Submitted to: Plant Disease
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/12/2013
Publication Date: 11/1/2013
Citation: Liu, M., Szabo, L.J., Hambleton, S., Anikster, Y., Kolmer, J.A. 2013. Molecular phylogenetic relationships of the brown leaf rust fungi on wheat, rye and other grasses. Plant Disease. 97:1408-1417. Interpretive Summary: Wheat, rye and related grasses are attacked by leaf rust fungi. The identfication and separation of these species based on structural characteristics of rust fungi has historically been difficult. This study used the molecular technique of DNA sequence variation to determine the relationship between leaf rusts from wheat, rye, and related species of wild grasses. At least six distinct groupings equivalent to distinct species were obtained, indicating that this group of rust fungi is very complex. These results can be used by plant pathologists, and mycologists for proper identification and classification of leaf rusts on wheat, rye and wild grasses to species level.
Technical Abstract: Phylogenetic analyses were conducted with DNA sequence data from the rDNA internal transcribed spacer region and elongation factor 1–alpha to elucidate the species complex of brown leaf rust fungi infecting wheat, rye and other grasses. Three phylogenetic lineages were recovered within the complex of rye leaf rust fungi, Puccinia recondita s. str., which is congruent with existing classifications based on DNA content, sexual compatibility, and morphological studies. The brown leaf rust fungus on wheat (P. triticina) grouped with P. persistens on Elymus repens and E. intermedia as a strongly supported clade. Collections on other Elymus spp. were separated into six clades. Based on the phylogenetic affinities of nine type specimens and aecial host associations, potential taxonomic names were evaluated for selected lineages.