You are viewing an archived copy of this website captured Mon Nov 05 11:36:57 AEDT 2012

All Content © CRC for Forestry 2007

Quantitative genetics of foundation eucalypts and their community consequences

European Union FoResTTraC Conference

"The Genetics of Foundation Species as Drivers of Ecological Processes"

February 16-18, 2011, Flagstaff Arizona

Brad Potts1,2, Julianne O’Reilly-Wapstra1,2, Matthew Hamilton1,2, Benjamin Gosney1, Jules Freeman1,2, Alison Miller1,2, Joseph Bailey1, Jennifer Schweitzer1, Thomas Whitham3, Greg Dutkowski1,4, Joao Costa e Silva5, Archana Gauli1,2, Tanya Bailey1,2, Neil Davidson1,2 and René Vaillancourt1,2

1School of Plant Science and 2CRC for Forestry, University of Tasmania, Private Bag 55, Hobart, Tasmania, 7001, Australia.  
3Department of Biological Sciences, and the Merriam-Powell Center for Environmental Research, Northern Arizona University, Flagstaff, AZ 86011, USA.
4PlantPlan Genetics, PO Box 1811, Mount Gambier, South Australia, 5290, Australia
5Centro de Estudos Florestais, Departamento de Engenharia Florestal, Instituto Superior de Agronomia, Universidade Técnica de Lisboa, Tapada da Ajuda, 1349-017 Lisboa Codex, Portugal.

There is increasing evidence that genetic variation in a foundation species may have significant flow-on effects to the associated biota and even to ecosystem processes.  Such extended genetic effects are especially important in forest trees, which dominate many natural terrestrial ecosystems, provide habitat for numerous dependent organisms and supply many important ecosystem services.  We have been studying these extended genetic effects in Eucalyptus globulus, a dominant tree of lowland forests of south-eastern Australia.  While native to Australia, the species is widely grown in plantations in temperate regions of the world and its molecular and quantitative genetic variation has been the subject of over two decades of research.  An extensive network of family trials from large, range-wide open-pollinated seed collections from native races and sub-races of E. globulus have been established for breeding and research purposes.  The natural colonization of these pedigreed field trials by local fungus, insect and marsupial species have provided a robust experimental system in which to study individual associated species and community level responses to genetic variation.  These responses have been explored at multiple genetic levels within E. globulus - from genetically divergent geographic races, additive genetic effects within races, to within family QTL effects.  We have been studying the drivers of these biotic responses, the genetic co-variance amongst dependent species, feedbacks to tree fitness, potential correlated responses to selection, and, more recently, the importance of indirect genetic effects in these artificial forests.

Using two dry-country eucalypt species, we are now studying extended genetic effects and diffuse interactions under different tree species mixtures and increasing community complexity.  By overlaying a genetic framework on multi-site and multi-community field trials we aim to better understand: (i) the impact of biotic and abiotic factors on the evolutionary trajectory of foundation species; (ii) the importance of tree genetics in determining the trajectory of the dependent community; as well as (iii) the requirements for developing resilient, bio-diverse tree plantings.  This understanding is important for the successful development of new forests for carbon sequestration and restoration purposes in the face of different climate change scenarios.

Biobuzz issue fourteen, May 2011