Molecular ecology of Acacia dealbata: Implications for effective management of invasive populations

Molecular ecology of  Acacia dealbata: Implications for  effective management of  invasive populations
Heidi Hirsch1, David M. Richardson1, Fiona A. C. Impson2, Johannes J. Le Roux1
1Centre for Invasion Biology, Stellenbosch University; 2Plant Protection Research Institute

Knowledge on the native provenance(s) of invasive plants in conjunction with a better understanding of coevolutionary processes between plants and potential biocontrol agents in their native ranges can help to develop effective control and management strategies. In this context, comparative studies between native and invasive populations can be useful approaches to gain more knowledge on the introduction history, potential niche and / or evolutionary shifts in invasive populations. Our research focuses on the invasion success of Acacia dealbata Link (silver wattle), a tree native to eastern and southeastern Australia and Tasmania. Introduced as a fast growing tree for shelterbelts, shade, firewood or horticulture, silver wattle has naturalized and is now considered as invasive in several countries (e.g. Chile, India, Portugal, South Africa, Spain, and the United States). However, only limited information is currently available on the characteristics of these invasive populations and the factors facilitating its invasiveness in these new ranges. We will provide an overview of our planned research approaches that consider the worldwide invasion success of A. dealbata. In addition to different comparative population genetic studies between native and invasive populations, we will also investigate biogeographic and subspecies-related patterns within its native range. Furthermore, a phylogenetic approach, including potential biological control agents, will be used to provide information on coevolutionary processes and thus host-specificity. Results from our research will help to gain a better knowledge of the supporting factors of the invasiveness of A. dealbata and to develop improved management strategies.