Studies in eucalypt genetics and evolution

This thesis represents over two decades of research on the genetics and evolution of Australia's iconic plant genus, Eucalyptus. I have undertaken this research in collaboration with numerous colleagues and the 25 PhD and 26 Honours students that I have supervised while employed at the University of Tasmania (see Acknowledgements). While mainly native to Australia (137), eucalypts were rapidly spread around the world following their discovery by Europeans. They are now the most widely grown hardwoods, and Australia's major germplasm contribution to the world (138). Our research has focused on species native to the island of Tasmania (43, 102). Only 29 species of eucalypts, from two subgenera are recognized as native to the island. A large component of this research is on E. globulus (sensu Brooker 2000, but treated as E. globulus ssp. globulus by some taxonomists). Eucalyptus globulus is the main eucalypt grown in hardwood plantations in Australia. It is also the species most widely grown in pulpwood plantations in temperate regions of the world and ranks amongst the 10 most planted forest tree species globally (154). The other Tasmanian species studied of international importance are E. gunnii, which is considered one of the most frost resistant of all eucalypts species and is grown on a small scale in plantations in southern France (8, 144), and E. regnans which is the tallest species of flowering plant in the world (47, 102). The genetic research undertaken has addressed fundamental issues in evolutionary biology as well as applied issues to support domestication programs, and gene pool management and conservation.