Nine novel species of <i>Huntiella</i> from southern China with three distinct mating strategies and variable levels of pathogenicity

The ascomycete genus <i>Huntiella</i> (Microascales) has a cosmopolitan distribution and occurs on a wide range of woody plants. Little is known regarding the identity, diversity, origin, or impact of these fungi in China. Recently, isolates of <i>Huntiella</i> spp. were collected from stumps of freshly felled trees or wounds on plantation-grown <i>Eucalyptus</i> in Guangdong, Guangxi, Fujian, and Hainan provinces of southern China. Additional isolates were obtained from stumps of <i>Acacia confusa</i> near <i>Eucalyptus</i> plantations in Hainan Province. The aim of this study was to identify these <i>Huntiella</i> species and to test their pathogenicity on <i>Eucalyptus</i> seedlings. Morphology and multigene phylogenies of the nuclear rDNA internal transcribed spacer (ITS1-5.8S-ITS2 = ITS) region and partial β-tubulin (<i>BT1</i>) and translation elongation factor 1α (<i>TEF1α</i>) genes revealed nine previously unknown <i>Huntiella</i> species, eight from <i>Eucalyptus</i> and one from <i>A. confusa</i>. The mating types of these species were determined, showing that seven are heterothallic, one is homothallic, and one is unisexual (<i>MAT1-2-1</i> gene). Pathogenicity tests showed that the nine <i>Huntiella</i> species can produce lesions on <i>Eucalyptus</i> seedlings, larger than wounds caused by controls on these plants. This study provides a basic understanding of the distribution, diversity, and pathogenicity of <i>Huntiella</i> species in southern China.