Dr Dan Blanchon
School of Landscape and Plant Science,
Private Bag 92025,
The genus Libertia is the only member of the iris family native to New Zealand, with seven species found from coastal to subalpine habitats. There are perhaps 12 species in the genus worldwide, and these are found in Andean South America, New Guinea, mainland Australia, Tasmania, and New Zealand.
For my PhD research I studied the morphology, anatomy, cytology and reproductive biology of the genus. The New Zealand species were found to be quite distinct morphologically, have a complex polyploid series (diploid to dodecaploid), complicated breeding relationships, and instances of hybridism.
In an attempt to study the evolutionary relationships of the New Zealand species of Libertia, and their relatives in Australia and South America, I used DNA sequencing (5S rDNA and trnL cpDNA). The results showed some complex relationships between the New Zealand species, suggesting that they fell within two lineages, but within these lineages there was little observable genetic difference between the species, despite a large morphological difference.
I am continuing this research and will be using DNA sequencing and/or DNA fingerprinting techniques to attempt to throw more light on the relationships of this plant group.