Australasian Plant Pathology

, Volume 42, Issue 1, pp 43–51 | Cite as

Taxonomic uncertainty and decision making for biosecurity: spatial models for myrtle/guava rust

  • J. ElithEmail author
  • J. Simpson
  • M. Hirsch
  • M. A. Burgman


The causal agent of myrtle rust, initially described as Uredo rangelii, was recorded in Australia for the first time in 2010. Much of the monitoring effort in Australia and elsewhere is driven by existing understanding of Puccinia psidii sensu lato (guava rust), because U. rangelii is part of the guava rust complex. Bioclimatic analyses for guava rust in Australia indicate highest risk along the eastern coast, from northern Queensland to the south coast of NSW. These analyses rely on native and invaded range records for Puccinia psidii sensu lato. However, models that are instead fitted to records representing U. rangelii emphasise different risk areas, with less focus on northern coastal Queensland and new predictions into NSW tablelands and north-eastern Victoria. These differences have important implications for biosecurity containment and monitoring efforts. Here we use this example as a case study to explore the implications of taxonomic uncertainty for predictions of the potential distribution of a species of biosecurity concern in Australia. The important message is that the different patterns implied by different taxonomic assumptions may have very different management implications and taxonomic uncertainty should be evaluated alongside other sources of uncertainty. We could find no published example where taxonomic uncertainty was evaluated in biosecurity planning, despite the fact that taxonomic uncertainties are common. We outline how to model such uncertainties and discuss methods for exploring them and their impacts on predicted distributions.


Biosecurity Eucalyptus rust Guava rust Species distribution models 



Jane Elith was supported by Australian Research Council grant FT0991640. Many people contributed to the location data for the species records—we thank them for this important resource and list sources in Online Appendix 1. The manuscript was substantially improved by helpful comments and suggestions from two anonymous reviewers and the editor, Dr Angus Carnegie.

Supplementary material

13313_2012_178_MOESM1_ESM.docx (827 kb)
ESM 1 (DOCX 826 kb)


  1. Alfenas AC, Zauza EAV, Mafia RG, Assis TF (2004) Clonagem e doenças do eucalipto. Universidad Federal de Viçosa, ViçosaGoogle Scholar
  2. Bock WJ (1992) The species concept in theory and practice. Zool Sci 9:697–712Google Scholar
  3. Booth T, Jovanovic T (2012) Assessing vulnerable areas for Puccinia psidii (eucalyptus rust) in Australia. Australas Plant Pathol 41:425–429CrossRefGoogle Scholar
  4. Booth TH, Old KM, Jovanovic T (2000) A preliminary assessment of high risk areas for Puccinia psidii (Eucalyptus rust) in the Neotropics and Australia. Agric Ecosyst Environ 82:295–301CrossRefGoogle Scholar
  5. Carnegie AJ, Cooper K (2011) Emergency response to the incursion of an exotic myrtaceous rust in Australia—Keynote paper APPS 2011. Australas Plant Pathol 40:346–359CrossRefGoogle Scholar
  6. Carnegie AJ, Lidbetter JR (2012) Rapidly expanding host range for Puccinia psidii sensu lato in Australia. Australas Plant Pathol 41:13–29CrossRefGoogle Scholar
  7. Carnegie AJ, Glen M, Mohammed C (2010a) Rapid screening of commercial forestry species to Uredo rangelii (myrtle rust) and distinguishing U. rangelii from Puccinia psidii (guava rust). Forests and Wood Products Australia Ltd. Report (Project No: PRC179-0910)Google Scholar
  8. Carnegie AJ, Lidbetter JR, Walker J, Horwood MA, Tesoriero L, Glen M, Priest MJ (2010b) Uredo rangelii, a taxon in the guava rust complex, newly recorded on Myrtaceae in Australia. Australas Plant Pathol 39:463–466CrossRefGoogle Scholar
  9. Colwell RK, Rangel TF (2009) Hutchinson's duality: The once and future niche. Proceedings of the National Academy of Sciences, 106:19651–19658Google Scholar
  10. Costello C, Polasky S (2008) Optimal harvesting of stochastic spatial resources. J Environ Econ Manag 56:1–18CrossRefGoogle Scholar
  11. Coutinho TA, Wingfield MJ, Alfenas AC, Crous PW (1998) Eucalyptus rust—a disease with the potential for serious international implications. Plant Dis 82:819–825CrossRefGoogle Scholar
  12. Elith J, Leathwick JR (2009) Species distribution models: ecological explanation and prediction across space and time. Annu Rev Ecol Evol Syst 40:677–697CrossRefGoogle Scholar
  13. Elith J, Kearney M, Phillips SJ (2010) The art of modelling range-shifting species. Method Ecol Evol 1(4):330–342CrossRefGoogle Scholar
  14. Elith J, Phillips SJ, Hastie T, Dudík M, Chee YE, Yates CJ (2011) A statistical explanation of MaxEnt for ecologists. Divers Distrib 17(1):43–57CrossRefGoogle Scholar
  15. Glen M, Alfenas AC, Zauza EAV, Wingfield MJ, Mohammed C (2007) Puccinia psidii: a threat to the Australian environment and economy—a review. Australas Plant Pathol 36:1–16CrossRefGoogle Scholar
  16. Grgurinovic CA, Walsh D, MacBeth F (2006) Eucalyptus rust caused by Puccinia psidii and the threat it poses to Australia. OEPP/EPPO Bull 36:486–489Google Scholar
  17. Hardiyanto EB, Tridasa AM (2000) Early performance Eucalyptus urophylla x E. grandis hybrid on several sites in Indonesia. In: Hybrid breeding and genetics of forest trees. Proceedings of QFRI/CRC-SPF Symposium, 9–14 April 2000, Noosa, Queensland, Australia. (Compiled by Dungey HS, Dieters MJ and Nikles DG), Department of Primary Industries, Brisbane pp 273–279. Available at: (accessed August 2012)
  18. Joffily J (1944) Ferrugem do Eucalipto. Bragantia 4:475–487Google Scholar
  19. Junghans DT, Alfenas AC, Brommonschenkel SH, Oda S, Mello EJ, Grattapaglia D (2003) Resistance to rust (Puccinia psidii Winter) in Eucalyptus: mode of inheritance and mapping of a major gene with RAPD markers. Theor Appl Genet 108:175–180PubMedCrossRefGoogle Scholar
  20. Killgore EM, Heu RA (2007) Ohia rust, Puccinia psidii Winter. New Pest Advisory 05–04. Available at (accessed 2 December 2012)
  21. Kriticos DJ, Leriche A (2008) The current and future potential distribution of Guava Rust, Puccinia psidii, in New Zealand. MAF Biosecurity New Zealand Technical Paper No: 2009/28. Client Report No. 12814. Ministry of Agriculture and Forestry New ZealandGoogle Scholar
  22. Langrell SRH, Glen M, Alfenas AC (2008) Molecular diagnosis of Puccinia psidii (guava rust)—a quarantine threat to Australian eucalypt and Myrtaceae biodiversity. Plant Pathol 57:687–701CrossRefGoogle Scholar
  23. Lawson BE, Day MD, Bowen M, van Klinken RD, Zalucki MP (2010) The effect of data sources and quality on the predictive capacity of CLIMEX models: an assessment of Teleonemia scrupulosa and Octotoma scabripennis for the biocontrol of Lantana camara in Australia. Biol Control 52:68–76CrossRefGoogle Scholar
  24. Loope L (2010) A summary of information on the rust Puccinia psidii winter (guava rust) with emphasis on means to prevent introduction of additional strains to Hawaii. US Geol Surv Open File Rep 2010–1082:1–31Google Scholar
  25. Loope L, La Rosa AM (2008) An analysis of the risk of the introduction of additional strains of the rust Puccinia psidii winter (‘Ohi’a rust) to Hawai’i. U.S. Geological Survey Open File Report 2008–1008. U.S. Geological Survey, RestonGoogle Scholar
  26. MacLachlan JD (1938) A rust of the pimento tree in Jamaica, BWI. Phytopathology 28:157–170Google Scholar
  27. Magarey RD, Fowler GA, Borchert DM, Sutton TB, Colunga-Garcia M, Simpson JA (2007) NAPPFAST: an internet system for the weather-based mapping of plant pathogens. Plant Dis 91:336–345CrossRefGoogle Scholar
  28. Mallet J (2001, 2007) Species, concepts of. In Levin, S. et al. (eds.) Encyclopedia of Biodiversity. Volume 5. Academic Press. pp. 427–440. Online update 1, pp. 1-15, Elsevier, OxfordGoogle Scholar
  29. Marlatt RB, Kimbrough JW (1979) Puccinia psidii on Pimenta dioica insouth Florida. Plant Dis Rep 63:510–512Google Scholar
  30. Martins MVV, Silveira SF, Maffia LA, Rocabado JMA, Mussi-Dias V (2011) Chemical control of guava rust (Puccinia psidii) in the northern region of Rio de Janeiro State, Brazil. Australas Plant Pathol 40:48–54CrossRefGoogle Scholar
  31. Morin L, Aveyard R, Lidbetter JR, Wilson PG (2012) Investigating the host-range of the rust fungus Puccinia psidii sensu lato across tribes of the FamilyMyrtaceae present in Australia. PLoS One 7(4):e35434. doi: 10.1371/journal.pone.0035434 PubMedCrossRefGoogle Scholar
  32. Old K (2007) Assessment of eucalypt rust as a pathogen of Eucalyptus spp. and other Myrtaceae, and development of sensitive methods for its detection in germplasm in Australia (FST/1996/206). In: Gordon J, Davis J (eds) Adoption of ACIAR project outputs: studies of projects completed in 2002–2003. ACIAR, Canberra, Available at Accessed June 2012Google Scholar
  33. Pearman PB, D’Amen M, Graham CH, Thuiller W, Zimmermann NE (2010) Within-taxon niche structure: niche conservatism, divergence and predicted effects of climate change. Ecography 33:990–1003CrossRefGoogle Scholar
  34. Phillips SJ, Anderson RP, Schapire RE (2006) Maximum entropy modeling of species geographic distributions. Ecol Model 190(3–4):231–259CrossRefGoogle Scholar
  35. Rayachhetry MB, Van TK, Center TD, Elliott ML (2001) Host range of Puccinia psidii, a potential biological control agent of Melaleuca quinquenervia in Florida. Biol Control 22:38–45CrossRefGoogle Scholar
  36. Regan HM, Colyvan M, Burgman MA (2002) A taxonomy and treatment of uncertainty for ecology and conservation biology. Ecol Appl 12:618–628CrossRefGoogle Scholar
  37. Ruiz RAR, Alfenas AC, Ferreira FA (1989) Effect of temperature, light and inoculum source on teliospore and urediniospore production of Puccinia psidii. Fitopatol Bras 14:70–73Google Scholar
  38. Schlick-Steiner BC, Steiner FM, Seifert B, Stauffer C, Christian E, Crozier RH (2010) Integrative taxonomy: a multisource approach to exploring biodiversity. Annu Rev Entomol 55:421–438PubMedCrossRefGoogle Scholar
  39. Simon H (1991) Bounded rationality and organizational learning. Organ Sci 2:125–134CrossRefGoogle Scholar
  40. Simon HA, Shaw JC, Newell A (1958) The processes of creative thinking. University of Colorado, BoulderGoogle Scholar
  41. Simpson JA, Thomas K, Grgurinovic CA (2006) Uredinales species pathogenic on species of Myrtaceae. Australas Plant Pathol 35:549–562CrossRefGoogle Scholar
  42. Venette RC, Kriticos DJ, Magarey RD, Koch FH, Baker RHA, Worner SP, Gómez Raboteaux NN, McKenney DW, Dobesberger EJ, Yemshanov D, De Barro PJ, Hutchison WD, Fowler G, Kalaris TM, Pedlar J (2010) Pest risk maps for invasive alien species: a roadmap for improvement. BioScience 60:349–362CrossRefGoogle Scholar
  43. Wellings CR, McIntosh RA, Walker J (1987) Puccinia striiformis f. sp. tritici in eastern Australia—possible means of entry and its implications for plant quarantine. Plant Pathol 36:239–241CrossRefGoogle Scholar
  44. Zauza EAZ, Couto MMF, Lana VM, Maffia MA, Alfenas AC (2010) Vertical spread of Puccinia psidii urediniospores and development of eucalyptus rust at different heights. Australas Plant Pathol 39:141–145CrossRefGoogle Scholar
  45. Zhong S, Yang B, Alfena AV (2008) Development of microsatellite markers for the guava rust fungus, Puccinia psidii. Mol Ecol Resour 8:348–350PubMedCrossRefGoogle Scholar

Copyright information

© Australasian Plant Pathology Society Inc. 2012

Authors and Affiliations

  • J. Elith
    • 1
    Email author
  • J. Simpson
    • 2
  • M. Hirsch
    • 3
  • M. A. Burgman
    • 1
  1. 1.Australian Centre of Excellence for Risk Analysis, School of BotanyUniversity of MelbourneParkvilleAustralia
  2. 2.NarrabundahAustralia
  3. 3.CSIROCanberraAustralia

Personalised recommendations