Epitypification of Tilletia ehrhartae, a smut fungus with potential for nature conservation, biosecurity and biocontrol

Tilletia ehrhartae, a smut fungus infecting perennial veldtgrass Ehrharta calycina, is epitypified and characterized using the Consolidated Species Concept, including morphology, ecology (host plant) and rDNA sequences (ITS and LSU). Tilletia ehrhartae is native and endemic to the Cape Floral Kingdom (located entirely in South Africa), but it has also been introduced to the alien artificial range of Ehrharta calycina in Australia and California. This smut has already caused some biosecurity problems in Australia as its spores were found to contaminate harvested wheat seeds, leading to confusion with Karnal bunt of wheat caused by Tilletia indica (which is absent in Australia), and therefore constituting a potential risk for Australian wheat export. The current global distribution of Tilletia ehrhartae, possible colonization history, and potential for nature conservation, biosecurity and biocontrol are discussed. The sequences generated in this work could serve as DNA barcodes to facilitate rapid identification of this important species.