Phylogenetic relationships of Australian and New Zealand Armillaria species

included in this study formed a monophyletic clade and confirmed separation of species based on morphology and sexual compatibility. Armillaria specie s cause Armillaria root rot on a wide range of plant species throughout the world. Based on morphology and sexual compatibility, various species of Ar millaria have been reported from Australia and New Zealand. These include A . hinnulea, A. fumosa, A. pallidula, A. novae-zelandiae and A. luteobubalin a from Australia. In New Zealand, A. limonea, A. novae-zelandiae, A. hinnul ea and a fourth undescribed but morphologically distinct species are recogn ized. To determine the phylogenetic relationships between Armillaria spp. f rom Australia and New Zealand, the ITS region (ITS 1, 5.8S rRNA gene and IT S2) of the rRNA operon was amplified and the DNA sequences determined for a collection of isolates. The ITS sequences of A. ostoyae (from USA) and A. sinapina (from USA) were included for comparison. Phylogenetic trees were g enerated using parsimony analysis. Armillaria hinnulea was found to be more closely related to Armillaria spp. occurring in the Northern Hemisphere th an it was to the other Australian and New Zealand species. The remainder of the Australian and New Zealand Armillaria spp.