Managing myrtle rust in Australia (2063) Dr GS Pegg (Agri-Science Queensland, Department of Agriculture & Fisheries), Dr AJ Carnegie (New South Wales Department of Primary Industries), Dr FR Giblin (The University of the Sunshine Coast), Dr S Perry (Biosecurity Queensland, Department of Agriculture & Fisheries). Puccinia psidii has long been considered a significant threat to Australian plant industries and native ecosystems. In 2010, P. psidii was detected for the first time in Australia on the central coast of New South Wales. Given the wind-borne nature of the disease and abundance of suitable hosts, the disease spread rapidly and is now considered established and widespread along the entire east coast of Australia. Since the disease was first recorded five years ago, the known host range of P. psidii in Australia has increased significantly, with field surveys identifying more than 346 host taxa (231 natural infections) from 57 genera of Myrtaceae. The geographical range of the disease continues to expand with recent detections from Bamaga Presenting author s biography and Melville Island in the tropics, and Tasmania in temperate Australia. Puccinia psidii has been identified from many different native Australian forest ecosystems including coastal heath, coastal and river wetlands, sand islands, and littoral, montane, subtropical and tropical rainforests. The disease impact of P. psidii on individual trees and shrubs ranges from minor leaf spots to dieback and reduced fecundity. Tree death as a result of repeated infection has also been recorded for some species, with regenerating seedlings killed by P. psidii. While the impact of P. psidii varies dependant on host and environment, it is widely recognised that the full impact of this disease on our native ecosystems in Australia may take many years to manifest. Dr Geoff Pegg is a Principle Forest Pathologist and Forest Health Team Leader with Queensland Department of Agriculture & Fisheries with over 15 years research experience in forest diseases. Dr Pegg has conducted research on myrtle rust since 2010, when the disease was first detected in Australia, studying impact on species and communities. Prior to working with DAF, Dr Pegg was a Supervising Inspector with the Australian Quarantine and Inspection Service working primarily in plant import and horticulture export programs. Geoff Pegg 07 3225 4381 geoff.pegg@daf.qld.gov.au Science Exchange 2015 Conference Handbook 85
Session Nine: Sharper responses to incursions Presentation title: Managing myrtle rust in Australia Presenter: Geoff Pegg
Project 2063 Managing myrtle rust in Australia Dr Geoff Pegg Team Leader Forest Health, DAF Dr Suzy Perry, Dr Fiona Giblin, Dr Angus Carnegie Plant Biosecurity Cooperative Research Centre
Problem being addressed General aim - Development of management strategies for myrtle rust Specific aim - 1. Develop and standardise field disease scoring Species susceptibility and impact - Host range - Impact on species within native ecosystems Identification of resistance/tolerance - Species conservation
Problem being addressed Specific aims contd. - 2. Disease screening methods Standardise methodology - Spore collection and inoculation - Assessment Resistant R1 Susceptible R4
Species screened for resistance A range of eucalypts Species/provenance/family Eucalyptus argophloia, E. camaldulensis, E. cloeziana, E. grandis, E. globulus, E. pellita, E. urophylla, E. ovata, E. pauciflora Corymbia citriodora subsp. citriodora, E. citriodora subsp. variegata, C. henryi, C. torelliana Collaborations Utas, CSIRO, FABI South Africa 3 papers published to date Lemon myrtle - Backhousia citriodora Provenances across the native range Melaleuca About to test 10 M. leucadendron, 12 M. viridiflora, 16 M. quinquenervia provenances
Results so far Melville Island 2015 Bamaga 2015 North Queensland April 2012 Central Queensland Jan 2012 Northern Territory Queensland Brisbane, Queensland Dec 2010 Western Australia South Australia New South Wales First detected April 2010; Gosford, NSW Victoria Dec 2011 Tasmania 2015 Victoria Tasmania
Results so far Host range & impact Host list over 300 species - Natural infection = 232 - Inoculated studies = 115-46 species rated as highly or extremely susceptible Giblin FR & Carnegie AJ (2014) Puccinia psidii (myrtle rust) - Australian host list. Version current at 23 Oct. 2014. http://www.anpc.asn.au/myrtle-rust Sites established to examine impact over time Impact on species Life stages affected Impact on species regeneration following disturbance
Impact on threatened Myrtaceae 23 species listed in Queensland as being threatened before myrtle rust 11 of these species have been identified as being highly/extremely susceptible to myrtle rust
Lenwebbia sp. Blackall Range - Threatened species 4 sites assessed across the native range Significant impact Site 1 All trees had significant levels of dieback - transparency rates >75% Impact on all life stages Seedlings Saplings Mature trees Infection on flowers A single tree identified with no disease Species recommended to be listed as Critically Endangered
Impact on widespread species Rhodomyrtus psidioides Native guava Conservation status Least Concern Fast growing Important successional role in rainforest regeneration Myrtle rust impact Most populations consist entirely of dead or dying trees Impacting on all life stages Regenerating seedlings & root suckers infected &/or killed Flowers/fruit infected Carnegie et al. Submitted 2015
Keystone species Melaleuca quinquenervia 30% of trees rated as resistant Rating 1 40% of trees rated as highly susceptible Rating 4 & 5 Rating 1 - Resistant Rating 4&5 Dead
Who will use research? Nursery industry - Production Species/variety selection host list/screening methodology Consumers general public, City/Shire Councils What species to avoid Environment - Data used to develop an application to have myrtle rust listed as a Threatening Process - Conservation Department of Environment policy development Revegetation programs - Forestry Requirement under the AFS to deal with issues threatening biodiversity
Who will directly benefit from the research? Production nurseries - Species selection - Screening/selection protocols City/Shire councils, general public - Species selection - Site management Environment - Federal and State Departments Species conservation
Challenges and issues arising from the research Threat to industry is lessened by the ability to select for resistance challenge arises with: - Uptake of recommendations - Responsibility to consumers Where to now for conserving species and environments impacted upon? - There is no clear process in place How do we manage impact in the native environment? - What value do we place on losing a plant species or changes in species composition? Threatened Keystone
Industry Impact delivery plan - Workshop - production nursery First workshop delivered Possible international workshop funding dependant - Disease screening methodology/guidelines Allow production nurseries to develop a screening process - Nursery publication on overall project outcomes - Scientific publications Eucalyptus screening Environment - Scientific publications Raising awareness for future policy development
The End-User Advocate s perspective John McDonald NGIQ Host list has helped guide species selection 2 issues that would be of benefit - Extend outcomes to a broader audience other than nursery Landscape, Councils, Landcare - Additional areas that could be addressed Improved understanding of disease impact in urban gardens species/cultivar performance Fungicide efficacy - Build on findings from PHA funded work
Thank you Peter Entwistle, Gordon Guymer, David Lee, John Huth, Bob Makinson, Jali Land Council For more information, please email geoff.pegg@daf.qld.gov.au