Diversity of Botryosphaeriaceae on Proteaceae in South Africa, Australia and Portugal

The Botryosphaeriaceae is an important and diverse family of latent fungal pathogens of woody plants. Because some species appear to have a worldwide distribution, they are increasingly being used as model organisms to understand patterns in the global movement of latent pathogens. The aim of this study was to consider the diversity of Botryosphaeriaceae on 14 native Proteaceae species across South Africa and Australia, as well as on South African plants grown in Portugal. Ten species of the Botryosphaeriaceae were identified from 200 isolates using sequence data of the ITS rDNA, TEF-1α and β-tubulin loci. Surprisingly, Neofusicoccum parvum was found only from Portugal materials, despite its global distribution and common occurrence in Australia and South Africa on the other hosts. Neofusicoccum protearum and N. australe were the only shared species in Australia, South Africa and Portugal, while Diplodia allocellula was found in Australia and South Africa. The other six species were obtained from a single country and include D. mutila, D. alatafructa and N. macroclavatum in Australia, and D. pseudoseriata, N. viticlavatum and N. cryptoaustrale in South Africa. The results of this study show that the Botryosphaeriaceae diversity on the Proteaceae is geographically distinct, but there is also evidence for specialist species, such as N. protearum, that have been transported globally with plant material.