Author
Muhammad Nawaz
muhammad.nawaz@dpird.nsw.gov.au
Weed Research Unit, Invasive Species Biosecurity, New South Wales Department of Primary Industries and Regional Development, Orange, Australia
Coauthors
Andrew McConnachie, Weed Research Unit, Invasive Species Biosecurity, New South Wales Department of Primary Industries and Regional Development, Orange, Australia
Graham Alexander, McCulloch, Department of Zoology, University of Otago, Dunedin, New Zealand
Abstract
Understanding the invasion history of weeds can assist practitioners in making informed decisions about weed management. This information often plays a vital role in the selection of potential biological control (biocontrol) agents in the native range and for anticipating their post-release impacts. In this study, we assessed the genetic structure of leaf cactus, Pereskia aculeata (Cactaceae), an emerging environmental weed in New South Wales (NSW) and Queensland (Qld) in Australia. Using a genotyping-by-sequencing (GBS) approach we assessed the population structure of P. aculeata across its native range (South America) and introduced ranges in Australia and South Africa. South African plants were very closely related to plants from Argentina and Brazil, suggesting they originated from that region. By contrast, the Australian plants were not genetically similar to any native range samples, leaving their provenance uncertain. Interestingly, we identified two distinct P. aculeata lineages in Australia: one in NSW and Qld, and the other in Far North Qld. This pattern may suggest there have been two independent introductions of P. aculeata into Australia. We recommend that the biology of these two distinct lineages be studied independently, and that each be treated separately during host-range testing.
keywords
genetic structure
invasion history
Highlights
We used GBS to assess genetic structure in leaf cactus across its native and introduced ranges
The South African plants likely originated from Argentina or Brazil
Two distinct P. aculeata lineages were found in Australia, suggesting two different introductions