Austropuccinia psidii (myrtle rust) is one of the most significant threats to plant industries and biodiversity in the Australasian region. Susceptibility phenotypes of Australian native Myrtaceae to A. psidii have varied significantly since the pathogen was first detected in Australia in 2010, with some species appearing to increase in susceptibility over time. We hypothesise that increased inoculum concentrations in natural ecosystems may be contributing to observed changes in susceptibility phenotypes. A study was undertaken to determine the effect of A. psidii inoculum concentration on myrtle rust disease incidence and severity on five native (Rhodamnia rubescens, Syzygium hemilamprum, S. leuhmanii, S. moorei and S. oleosum) and one exotic (S. jambos) species of Myrtaceae under controlled conditions. Disease incidence and severity were found to increase across all species as inoculum concentration increased, with notable increases for species considered to be tolerant or of lower susceptibility to A. psidii. This improved understanding of the influence of increasing inoculum A. psidii concentrations on susceptibility phenotypes can now be integrated with current management and research plans, to predict and mitigate the impact of A. psidii on Australian native biota and ecosystems.
This is a preview of subscription content, access via your institution.
Buy single article
Instant access to the full article PDF.
Tax calculation will be finalised during checkout.
Subscribe to journal
Immediate online access to all issues from 2019. Subscription will auto renew annually.
Tax calculation will be finalised during checkout.
Beenken L (2017) Austropuccinia: a new genus name for the myrtle rust Puccinia psidii placed within the redefined family Sphaerophragmiaceae (Pucciniales). Phytotaxa 297:53–61. https://doi.org/10.11646/phytotaxa.297.1.5
Berthon K, Esperon-Rodriguez M, Beaumont LJ, Carnegie AJ, Leishman MR (2018) Assessment and prioritisation of plant species at risk from myrtle rust (Austropuccinia psidii) under current and future climates in. Australia Biol Conserv 218:154–162. https://doi.org/10.1016/j.biocon.2017.11.035
Borges LS, Rios JA, Aucique-Perez CE, Belisario R, Duarte HDS, Furtado GQ (2019) Standard area diagram set to assess rust severity on eucalyptus leaves. For Pathol 49 https://doi.org/10.1111/efp.12510
Carnegie AJ, Lidbetter JR, Walker J, Horwood MA, Tesoriero L, Glen M, Priest MJ (2010) Uredo rangelii, a taxon in the guava rust complex, newly recorded on Myrtaceae in Australia Australasian. Plant Pathol 39:463–466. https://doi.org/10.1071/ap10102
Carnegie AJ (2015) First Report of Puccinia psidii (Myrtle Rust) in Eucalyptus Plantations in. Aust Plant Dis 99:161–161. https://doi.org/10.1094/pdis-09-14-0901-pdn
Carnegie AJ, Kathuria A, Pegg GS, Entwistle P, Nagel M, Giblin FR (2016) Impact of the invasive rust Puccinia psidii (myrtle rust) on native Myrtaceae in natural ecosystems in Australia. Biol Invasions 18:127–144. https://doi.org/10.1007/s10530-015-0996-y
Carnegie AJ, Pegg GS (2018) Lessons from the Incursion of Myrtle Rust in Australia. In: Leach JE, Lindow SE (eds) Annual Review of Phytopathology, Vol 56. Annual Review of Phytopathology. pp 457–478. https://doi.org/10.1146/annurev-phyto-080516-035256
Coutinho TA, Wingfield MJ, Alfenas AC, Crous PW (1998) Eucalyptus rust: a disease with the potential for serious international implications. Plant Dis 82:819–825. https://doi.org/10.1094/pdis.19220.127.116.119
Dale AL et al (2019) Mitotic recombination and rapid genome evolution in the invasive forest pathogen Phytophthora ramorum. mBio 10:e02452-02418. https://doi.org/10.1128/mBio.02452-18
Doran J, Lea D, Bush D (2012) Assessing myrtle rust in a lemon myrtle provenance trial. Rural Industries Research and Development Corporation, Barton
Fernandez Winzer L, Carnegie AJ, Pegg GS, Leishman MR (2018) Impacts of the invasive fungus Austropuccinia psidii (myrtle rust) on three Australian Myrtaceae species of coastal swamp woodland. Austral Ecol 43:56–68. https://doi.org/10.1111/aec.12534
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 36:1–16. https://doi.org/10.1071/ap06088
Grünwald NJ, LeBoldus JM, Hamelin RC (2019) Ecology and evolution of the Sudden Oak Death pathogen Phytophthora ramorum. Annu Rev Phytopathol 57:301–321. https://doi.org/10.1146/annurev-phyto-082718-100117
Ireland KB, Hüberli D, Dell B, Smith IW, Rizzo DM, Hardy GESJ (2012) Potential susceptibility of Australian flora to a NA2 isolate of Phytophthora ramorum and pathogen sporulation potential. For Pathol 42:305–320. https://doi.org/10.1111/j.1439-0329.2011.00755.x
Ireland KB, Hunter GC, Wood A, Delaisse C, Morin L (2019) Evaluation of the rust fungus Puccinia rapipes for biological control of Lycium ferocissimum (African boxthorn) in Australia: life cycle. taxonomy pathogenicity Fungal Biology 123:811–823. https://doi.org/10.1016/j.funbio.2019.08.007
Junghans DT, Alfenas AC, Maffia LA (2003) Escala de notas para quantificação da ferrugem em. Eucalyptus Fitopatologia Brasileira 28:184–188
Kanaskie A et al (2017) Slowing spread of sudden oak death in Oregon forests, 2001–2015 [Abstract]. In: Frankel SJ, Harrell KM, coords t (eds) Proceedings of the sudden oak death sixth science symposium. Gen. Tech. Rep. GTR-PSW-255. U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station, Albany, CA, p 1
Lee DJ, Brawner JT, Pegg GS (2015) Screening eucalyptus cloeziana and E-argophloia populations for resistance to Puccinia psidii. Plant Dis 99:71–79
McTaggart AR et al (2018) Chromium sequencing: the doors open for genomics of obligate plant pathogens. BioTechniques 65:253–256. https://doi.org/10.2144/btn-2018-0019
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 family Myrtaceae present in Australia. Plos One 7:7. https://doi.org/10.1371/journal.pone.0035434
O’Hanlon R, Choiseul J, Brennan JM, Grogan H (2018) Assessment of the eradication measures applied to Phytophthora ramorum in Irish Larix kaempferi forests. For Pathol 48:e12389. https://doi.org/10.1111/efp.12389
Pegg GS, Brawner JT, Lee DJ (2014) Screening Corymbia populations for resistance to Puccinia psidii. Plant Pathol 63:425–436. https://doi.org/10.1111/ppa.12097
Pegg GS et al (2014) Puccinia psidii in Queensland, Australia: disease symptoms. distribution impact Plant Pathol 63:1005–1021. https://doi.org/10.1111/ppa.12173
Pegg G, Taylor T, Entwistle P, Guymer G, Giblin F, Carnegie A (2017) Impact of Austropuccinia psidii (myrtle rust) on Myrtaceae-rich wet sclerophyll forests in south east Queensland. Plos One 12. https://doi.org/10.1371/journal.pone.0188058
Pegg GS, Lee DJ, Carnegie AJ (2018) Predicting impact of Austropuccinia psidii on populations of broad leaved Melaleuca species in Australia. Australas Plant Pathol 47:421–430. https://doi.org/10.1007/s13313-018-0574-8
R Core Team (2019) R: a language and environment for statistical computing. R Foundation for Statistical Computing, Vienna
Swiecki T, Bernhardt E (2008) Increasing distance from California bay laurel reduces the risk and severity of Phytophthora ramorum canker in coast live oak. In: Frankel S, Kliejunas J, Palmieri K, coords t (eds) Proceedings of the sudden oak death third science symposium. Gen. Tech. Rep. PSW-GTR-214. U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station, Albany, CA, pp 181–194
Tobias PA, Park RF, Kulheim C, Guest DI (2015) Wild-sourced Chamelaucium uncinatum have no resistance to Puccinia psidii (myrtle rust). Aust Plant Dis Notes 10 https://doi.org/10.1007/s13314-015-0167-0
Tobias PA, Guest DI, Külheim C, Hsieh J-F, Park RF (2016) A curious case of resistance to a new encounter pathogen: myrtle rust in Australia. Mol Plant Pathol 17:783–788. https://doi.org/10.1111/mpp.12331
Tobias PA, Guest DI, Kulheim C, Park RF (2018) De novo transcriptome study identifies candidate genes involved in resistance to & IT;Austropuccinia psidii & IT; (Myrtle Rust) in & IT;Syzygium luehmannii & IT;(Riberry). Phytopathology 108:627–640. https://doi.org/10.1094/phyto-09-17-0298-r
Uchida JY, Loope LL (2009) A recurrent epiphytotic of guava rust on rose apple, Syzygium jmbos in Hawaii. Plant Dis 93:429–429. https://doi.org/10.1094/pdis-93-4-0429b
Webber JF (2017) Phytophthora ramorum: update on the impact and wider consequences of the epidemic in Britain. In: Frankel SJ, Harrell KM, coords t (eds) Proceedings of the sudden oak death sixth science symposium. Gen. Tech. Rep. GTR-PSW-255. U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station, Albany, CA, pp 4–6
Xavier AA, Alfenas AC, Matsuoka K, Hodges CS (2001) Infection of resistant and susceptible Eucalyptus grandis genotypes by urediniospores of Puccinia psidii. Australas Plant Pathol 30:277–281. https://doi.org/10.1071/ap01038
Zauza EAV, Couto MMF, Lana VM, Maffia LA, Alfenas AC (2010) Vertical spread of Puccinia psidii urediniospores and development of eucalyptus rust at different heights. Australas Plant Pathol 39:141–145. https://doi.org/10.1071/ap09073
Zauza EAV, Lana VM, Maffia LA, Araujo MMFC, Alfenas RF, Silva FF, Alfenas AC (2015) Wind dispersal of Puccinia psidii urediniospores and progress of eucalypt rust. For Pathol 45:102–110. https://doi.org/10.1111/efp.12133
We acknowledge the support of the Australian Government’s Cooperative Research Centres Program and Queensland government’s Myrtle Rust Program. This work formed a part of the Plant Biosecurity CRC project 70186: Understanding myrtle rust epidemiology and host specificity to determine disease impact in Australia. We would also like to acknowledge the efforts of the reviewers and thank them for their valuable feedback.
Electronic supplementary material
About this article
Cite this article
Ireland, K.B., Pegg, G.S. Effect of Austropuccinia psidii inoculum concentration on myrtle rust disease incidence and severity. Australasian Plant Pathol. 49, 239–243 (2020). https://doi.org/10.1007/s13313-020-00699-4
- Eucalyptus rust
- Puccinia psidii
- host specificity
- host susceptibility