New national project to sequence Australia’s native plant genomes

Published 12 December 2018
Tea tree Melaleuca alternifolia in bloom Tea tree (Melaleuca alternifolia) in bloom (credit: Merv Shepherd).

Southern Cross University will lend its plant science expertise to a bold new national project that aims to map the genomes of Australian native plants to better understand and conserve the country’s unique flora.

Professor Graham King Southern Cross Plant Science
Professor Graham King

The Genomics for Australian Plants Framework Initiative, launched last week in Brisbane, will create genomic infrastructure across the ‘Plant Tree of Life’ with the sequencing of key native plant specimen/species. The integrated network of researchers, data specialists, and state and national government agencies will collaborate in the collection, management, dissemination and application of genomic data for Australian plants.

Southern Cross University has already lent its expertise to the nationwide collaborative project through Professor Graham King, an internationally renowned plant science and genetics expert who is on the Genomics for Australian Plants (GAP) Steering Committee.

The University also partners with its unique Medicinal Plant Herbarium and with the Southern Cross Plant Science research centre’s computing infrastructure and expertise in genome assembly and analysis.

“Southern Cross University will continue be provide its know-how, facilities and data to assist the GAP project as the initiative develops,” said Professor Graham King.

“The Australian climate has provided a rugged environment in which a large number of plant species have adapted and survived over tens of millions of years.

“Apart from issues of conservation and protecting the wonderfully unique and diverse Australian flora, it is important that we understand the basis and context of genetic variation that underpins important regional industries such as tea tree and macadamia.” 

Southern Cross University already has research programs underway focused on genomes of the iconic and economically valuable Australian plants macadamia and tea tree, both endemic to the NSW Northern Rivers.

“Both crop-based industries are founded on Indigenous knowledge and germplasm that is local to the Northern Rivers region. These tea tree and macadamia species are the tip of the iceberg in terms of potential crops to feed, sustain and maintain a healthy human population on an increasingly fragile planet,” Professor King said.

“The GAP initiative offers a great opportunity to explore further the vast range of unique essential oils present within the Australian flora, as well as the significant numbers of indigenous medicinal and food plants.

“As partners within GAP, the University’s Medicinal Plant Herbarium has documented a wide range of useful species and this is supplemented by a unique collection of essential oils. Being able to generate genome DNA data for each of these species and understand phytochemical variation between and within species will greatly enhance our understanding of how such chemical diversity evolves in response to challenging environments.”

The initial pilot for the Genomics for Australian Plants Framework Initiative will focus on three species: the golden wattle (Acacia pycnantha) native to the ACT and the floral emblem of Australia; an Australian endemic spider flower native to WA (Areocleome oxalidea); and the Waratah (Telopea speciosissima) native to the south-eastern parts of Australia and the NSW state emblem.

 

Backgrounder: Southern Cross University’s research into macadamia and tea tree

Macadamia is the only Australian native plant developed as a major international food crop. Its origins is as a genus of subtropical rainforest tree within the Gondwanian plant family Proteaecae. The macadamia nut crop is derived from two species.

Dr Cathy Nock at Southern Cross Plant Science is leading the Australian effort to develop the first reference genome for this family, focused on the commercially important species Macadamia integrifolia. This has involved working with the Macadamia Conservation Trust to help confirm the distribution and likely population structure of the other important species M. tetraphylla.

M. tetraphylla is listed as vulnerable and is one of the two species from which the macadamia nut crop was derived; the first commercial orchard was in 1882 at Rous Mill, near Lismore. The fragmented populations of M. tetraphylla in northern NSW represent the isolated remnants of the once extensive subtropical ‘Big Scrub’ rainforest of which 99% was cleared following European settlement

There are concerns around conservation of the relatively reduced M. tetraphyla genepool particularly in light of recent evidence for crop-wild gene flow. M. tetraphylla has been used widely as a rootstock. Development of genomic resources is expected to open up areas of research relating to valuable alleles for pest and disease resistance, and for study of the unique proteoid roots.

The University’s current genetic research on Macadamia is supported by HortInnovation, the Australian and NSW governments, Knappick Foundation, Australian Macadamia Society, and Macadamia Conservation Trust.

Tea tree has become an important and iconic export from Australia. Extracted from the myrtaceous species Melaleuca alternifolia, this antiseptic essential oil underpins an industry worth around $35 million a year.

Southern Cross University currently manages the ATTIA (Australian Tea Tree Industry Association) tea tree breeding program, with levy funds and support from the Australian government. Alongside this, work has started at Southern Cross on sequencing the genome of tea tree, and this will be compared with existing genomes already generated for other Myrtaceae species such as Corymbia (spotted gum), a project also led by the University, and Eucalyptus grandis. The latter two species are native to Australia and underpin important forestry industries both here and overseas.

 

Media contact: Sharlene King 0429 661 349, scumedia@scu.edu.au