Fighting myrtle rust with gardens’ data: which Myrtaceae already live in ex situ collections? Damian Wrigley, National Coordinator, Australian Seed Bank Partnership; Brett Summerell, Chief Scientist and Director Research, Australian Institute of Botanical Science, Royal Botanic Gardens and Domain Trust, Sydney; John Arnott, Manager of Horticulture, Royal Botanic Gardens Victoria, Cranbourne and Emma Simpkins, Botanical Records and Conservation Officer, Auckland Botanic Gardens Australian botanic gardens, their nurseries and seed banks hold diverse collections of native plants and germplasm, including many iconic species within the family Myrtaceae. Well-known Australian plants such as the lilly pillies, bottlebrushes, paperbarks and tea trees fall within this family, along with many others, conjuring images of some of the rich and diverse forests, swamps and coastal scrub where members of the family can be encountered. Myrtaceae also includes the iconic eucalyptus, a genus synonymous with the Australian landscape, possessing a wealth of species diversity and high levels of endemism. This diversity and endemism across the eucalypts can be seen reflected, at least partially, in the living collections of botanic gardens, where morphological distinctions between species are often relied upon to highlight and illustrate the genetic complexity within the genus. Such collections, including those of other Myrtaceae,
Melaleuca quinquenervia heavily infected with myrtle rust (Austropuccinia psidii). Credit: Geoff Pegg
require targeted curation and long-term strategic management to maintain their health, rigour and relevance to public programs and conservation priorities. It would simply not be feasible to replicate these gardens’ displays for all native Myrtaceae, particularly when it is estimated that over 80 genera within the family are endemic to Australia (Makinson et. al. 2020). With so many endemic Myrtaceae in Australia, alternative options for conserving them ex situ are needed. Many species not on display are already kept secure for the short-term in botanic gardens’ nurseries, while other, more orthodox species rely on seed banks to provide a longer‑term storage solution. Those species already secured ex situ in Australia and overseas in botanic gardens, nurseries and seed banks may be some of the luckiest family members.
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THE BOTANIC GARDENer | ISS 58 Winter 2022
