Projects seeking sponsorship

These are projects approved by the Scientific Research Committee and seeking support.

Projects for financial year 2007/08

Conservation of Genetic Diversity in the Doryanthaceae
Professor Robert Henry - Director, Centre for Plant Conservation Genetics
Southern Cross University
PO Box 157 Lismore NSW 2480
Ph: (02) 6620 3010
Email: robert.henry@scu.edu.au

Aim
The aim of this project is to support the conservation of Doryanthes by understanding the relationships between populations and their levels of genetic diversity. Doryanthes are increasingly important in cultivation for their aesthetic value. Genetic analysis will be used to determine appropriate management of current wild populations to ensure conservation of diversity and define risks to wild populations associated with gene flow from cultivated plants.

Background
The Gymea lily, Doryanthes excelsa and the giant spear lily, D. palmeri are the only species in the Doryanthaceae, a unique Australian plant family with no close relatives in the Asparagales (Chase 2005). Recent research has led to recommendations that such phylogenetically distinct taxa be prioritised in conservation efforts, in order to preserve the evolutionary potential of flora into the future (Forest et al. 2007).

Populations of each species of Doryanthes are geographically isolated, many consisting of less than a few hundred individuals. The northern species D. palmeri is listed as a vulnerable in NSW. To date, there is in no management plan for the species however it is considered that D. palmeri is likely to become endangered unless factors threatening its survival or evolutionary development cease to operate (NSW Scientific Committee 2002).

Doryanthes have been successfully propagated and are becoming important cultivated plants for the nursery and landscaping industries. The impressive red flower spikes can reach up to 5 metres (Harden 1993). An increasing demand for cut flowers from D. excelsa in domestic and export markets is mostly met by harvest from wild stands. This has the potential to threaten the long-term viability of wild populations as individuals are thought to take up to 10 years to first flower. Although Doryanthes are increasingly popular in cultivation, little is known of their biology and genetic status in the wild.

Pilot Research
Recent research at our facility, the Centre for Plant Conservation Genetics (CPCG), used chloroplast DNA to measure levels of evolutionary divergence between Doryanthes and related families in the Asparagales. The results indicate that some populations of D. palmeri are genetically isolated. A herbarium specimen contained a unique genetic profile suggesting that one distinct population may be extinct in the wild and surviving only in a botanical garden.

Chloroplast DNA is ideal for systematic studies but provides limited information for studies of population structure, hybridisation, levels of genetic diversity, clonal reproduction and dispersal: information critical to conservation management. Microsatellites (SSR) are the markers of choice for conservation genetic studies as they are codominant and can show high levels of variation, even in endangered species. Pilot research has produced sequence data for a suite of SSR markers specific to D. palmeri. These markers now require testing for cross species amplification in D. excelsa and for variability within each species of Doryanthes.

Research Protocol
Levels of genetic diversity and gene flow within and between geographically isolated populations of Doryanthes will be measured using microsatellite (SSR) markers. Samples from 92 D. palmeri and 93 D. excelsa individuals have been collected from sites across eastern NSW and Queensland, herbariums and botanical gardens. A graduate (honours) student will be trained in plant conservation genetics under the supervision of Professor Robert Henry, a world renowned authority in plant genetics with a special interest in the conservation of rare and endemic Australian plant species.

The student will utilise the SSR sequence data to isolate specific and variable SSR markers for Doryanthes. It is anticipated that 10 to 20 markers will be amplified using polymerase chain reactions (PCR) in DNA extracted from 185 Doryanthes samples to provide a genotype, or genetic profile for each. Analyses of genotype data will provide estimates of levels of variation within and between species, hybridisation, levels of selfing and clonal reproduction within wild populations and dispersal between geographically isolated populations. This research will determine the extent to which populations vary and suggest appropriate conservation strategies to ensure diversity is retained in wild populations.

The CPCG, Southern Cross University, conducts research aimed at utilising and conserving plant genetic resources in crops, forests and environmentally important species. CPCG laboratories are fully equipped to support genetic research using advanced biotechnologies on a wide range of plant species. CPCG employs a team of more than fifty scientists, technicians, PhD students and support staff with an impressive breadth of experience.

Costs
Samples have been collected previously and are stored at CPCG. A graduate student will undertake the laboratory work from February 2008 to September 2008. The estimated expenses of this project relate only to the genetic analyses of these samples:

Summary
The proposed project encompasses all four Australian Flora Foundation categories: Doryanthes are rare, endemic Australian plants. Doryanthes are currently cultivated to meet an increasing demand from the floriculture, nursery, and landscape industries. The project will also train a student in the conservation genetics of Australian plants. This research will provide information about levels of genetic diversity and gene flow between wild and cultivated populations that will assist in the conservation of this distinct family.

Applicant Details
Professor Robert Henry - Director, Centre for Plant Conservation Genetics
Southern Cross University
PO Box 157 Lismore NSW 2480
Ph: (02) 6620 3010
Email: robert.henry@scu.edu.au

References
Chase, MW (2005) Relationships between the families of flowering plants. Plant Diversity and Evolution Ed. RH Henry, CABI Publishing.
Forest, F et al. (2007) Preserving the evolutionary potential of floras in biodiversity hotspots. Nature 445: 757-760.
Harden, GJ (1993) Doryanthaceae Flora of New South Wales Vol 4 UNSW Press.
NSW Scientific Committee (2002) Doryanthes palmeri (giant rosette plant) Vulnerable species determination: final decision (NSW).

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