A lack of genetically compatible mates constrains the spread of an invasive weed

Akane Uesugi, David J. Baker, Nissanka de Silva, Kristin Nurkowski, Kathryn A. Hodgins

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2 Citations (Scopus)


Introduced populations often experience lag times before invasion, but the mechanisms constraining rapid expansions of introduced populations are unclear. Solidago altissima is a North American native plant with highly invasive Japanese populations and introduced Australian populations that are not invasive despite the climatic and ecological suitability of the region. By contrasting Australian with Japanese populations, we tested the hypothesis that Australian population growth is limited by a lack of long-distance dispersal via seeds owing to a limited number of compatible mates. In the field, Australian populations rarely produced viable seeds. A cross-pollination experiment found that Australian plants are fertile, yet lack compatible mates within Australia. Genetic analysis revealed that Australian individuals descend from a small set of self-incompatible genetic clones, which explains the negligible seed set within Australia. Our results show that low genetic diversity, leading to mate incompatibility, inhibits invasiveness of Australian S. altissima, and provides compelling evidence for genetic, rather than ecological, factors constraining invasion in Australia.

Original languageEnglish
Number of pages9
JournalNew Phytologist
Issue number6
Publication statusPublished - Jun 2020


  • Allee effect
  • genotype-by-sequencing
  • invasive species
  • lag time
  • seed limitation
  • self-incompatibility
  • Solidago altissima

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