Puccinia tritici-golanensis, a new wheat leaf rust pathogen from Yonatan region of the Golan Heights, Puccinia tritici-duri and Puccinia triticina typified, and their phylogenetic relationships

Abstract The fungi causing diseases of cereal crops and other grasses, known as the brown leaf rusts, have historically been classified in the Puccinia recondita (sensu lato) species complex. Despite a long history of taxonomic effort, the recognition of the many included discrete taxa has been challenged due to overlapping morphological characters and primary grass hosts. More recent studies employing DNA sequence analyses identified multiple phylogenetic lineages in the complex, with two corresponding to species important to agricultural production, Puccinia triticina and P. recondita sensu stricto, on wheat and rye respectively. In this study, a second wheat-associated species, Puccinia tritici-duri , as yet known only from the Mediterranean region, and a new species recently discovered in the Golan Heights on wild emmer wheat, were examined and compared with P. triticina . We conducted detailed morphological examinations of telial and uredinial stages, DNA sequence analyses of the ribosomal DNA internal transcribed spacer region and elongation factor 1-α, and greenhouse inoculation experiments using a broad selection of Triticum and Aegilops telial hosts. The results demonstrated that the three wheat-associated species are distinct, placed in three unrelated lineages within the P. recondita complex. They confirm an overlap in host associations, which varied depending on species or cultivar. Based on the combined evidence, we formally propose the new species as Puccinia tritici-golanensis and provide comprehensive notes for the other two species, supported by descriptions and illustrations.