PRESS SUMMARY

Guava rust (Puccinia psidii) is one of the most serious disease threats to Australian native flora.

It attacks eucalypts and other myrtaceous species, and has the potential to dramatically affect a wide range of Australian species, with potentially devastating consequences to some endangered plants and animals that depend on them for survival (e.g. koalas).

Endemic to South America, guava rust has since the mid 2000s been moving across the Pacific. On April 22^nd 2010, a member of the guava rust complex, Uredo rangelii was detected on the Central Coast of NSW.  There is a real concern that the disease caused by Uredo rangelii will not be significantly different to that caused by Puccinia psidii.

The Australasian Plant Pathology Society (APPS), the lead organisation representing Australasian plant pathologists, believes that necessary funding and more action are urgently needed to:

   (i)         Strenuously attempt eradication of the incursion

   (ii)        Establish a committee of relevant experts to provide expert advice on how best to deal with the incursion

Australasian plant pathologists are concerned that action and responses to address the problem, and to alert authorities and interest groups to the potentially devastating consequences of the outbreak, have been insufficient to maximise the chances of eradication.

We stand ready to help in whatever way we can.

As a contribution to boosting efforts to respond to this new threat to the Australian Flora, the Society has launched a call for donations to its Advancing Plant Pathology Australia Fund which will be used to fund research on the problem (http://www.australasianplantpathologysociety.org.au/app_fund.html).

Release Date - 8 June 2010 –

http://www.australasianplantpathologysociety.org.au/Press_Releases/

Reference:

Angus Carnegie, John Walker, Jonathan Lidbetter, Len Tesoriero, Martin Horwood, Morag Glen, Michael Priest 2010. Uredo rangelii, a taxon in the guava rust complex, newly recorded on Myrtaceae in Australia Australasian Plant Pathology 39: http://www.publish.csiro.au/view/journals/dsp_journal_fulltext.cfm?nid=39&f=AP10102

APPS - Media Enquiries:

Myrtle Rust - APPS Media Spokespersons

Dr Caroline Mohammed, President, APPS – 0417362410

Email: President@APPSnet.org

Professor Giles Hardy- 08- 93606272 Mobile - 0429207793

Dr Ken Old - 02-62363284

Mr Ian Smith – 0408078270

Images: 

http://www.australasianplantpathologysociety.org.au/Press_Releases/press_release_2.html

Further reading:

http://www.australasianplantpathologysociety.org.au/Press_Releases/press_release_3.html

Enquiries and Donations to the Advancing Plant Pathology Australia Fund:

 http://www.australasianplantpathologysociety.org.au/app_fund.html

Contacts about the Fund or APPS:

Dr Peter Williamson, APPS Business Manager - 07- 46320467  Mobile: 0408745196

Email business_manager@appsnet.org

Dr Greg Johnson APPS Immediate Past President - 02- 62515658 Mobile 0405087870

Email: past_president@appsnet.org

Myrtle rust – Guava rust complex: Background and Recommended Actions from the Australasian Plant Pathology Society Inc.

Myrtle rust, caused by Uredo rangelii, was detected on the Central Coast of NSW on 22^nd April 2010. 

Uredo rangelii is considered to be within the guava rust complex.  Guava rust, caused by Puccinia psidii, is a significant disease of Myrtaceae in South America and several other countries.  Australia contains approximately half of the 150 genera and more than 3000 species of known Myrtaceae worldwide.

Uredo rangelii is known from Myrtus and Syzygium in South America, and has so far been found on Agonis flexuosa, Callistemon viminalis and Syncarpia glomulifera (turpentine) in Australia. 

Surveys up to 3^rd June 2010 confirmed myrtle rust on four properties (2 cut flower farms, 2 nurseries), but not in native forest or turpentine windbreaks in the region.  Containment operations are continuing at one property and infected material has been destroyed at three other properties.

Under Plant Plan[1], a Consultative Committee on Exotic Plant Pests was convened on 27^th April 2010 but a Scientific Advisory Panel (SAP) was not formed. 

The CCEPP decided that myrtle rust could not be eradicated, and this was agreed to by the National Management Group². 

The Emergency Response (delimiting surveys and control operations) was stood down on 30^th April. 

However, NSW (including Industry & Investment, Forests NSW, DECCW) decided to continue surveys and containment operations.  The majority of this work is being conducted by the Forest Health Survey Unit at I&I NSW and APPS commends this action.

Subsequently the CCEPP was asked to reconsider its decision by Plant Health Australia and decided that more information which delimited the infection was required. 

In the absence of cost sharing by the Commonwealth and State and Territory Governments the response is likely to be short-lived due to tight budgetary constraints imposed on I&I NSW. 

There is a real concern that the disease caused by Uredo rangelii (myrtle rust) will not be significantly different to that caused by Puccinia psidii (guava rust).  Each strain of the guava rust complex has a broad host range when pathogenicity tests have been performed overseas.

Thus, concerns are that myrtle rust will cause significant disease to commercial hardwood forestry species and to native Myrtaceae in Australia. The lack of a funding mechanism to rapidly respond to environmental biosecurity threats of national significance has become apparent.

The decision that this fungal pathogen was not eradicable was based on knowledge about the behaviour of rust fungi in general and limited survey data about the incursion.

A contingency plan that provides guidelines and options for steps to be undertaken and considered when developing a Response Plan to a pest was available for guava rust ³. The guava rust contingency plan was not adopted even though myrtle rust is recognised as a member of the guava rust species complex.

The decision to not attempt eradication was premature as ongoing surveys have found only limited infection in linked sites.

Weather conditions on the Somersby Plateau, NSW were optimal for infection (based on data from P. psidii) in April and early May 2010.

As we go into winter, night temperatures at the infection sites are falling below that required for rust spore germination.

There is still a window of opportunity to eradicate this rust if extensive infections are not found in surrounding native vegetation which includes turpentine.

The biosecurity response to the new incursion of Uredo rangelii in NSW has evolved without formal consultation with the forest and cut flower industries as neither industry is signatory to the EPPRD (though the nursery and garden industry is signatory to the deed).

On the available information eradication may still be feasible if further spread is prevented. Aggressive action against the pathogen should be maintained.

Even if eradication is not achieved, containment will allow time for management actions to be developed and implemented to potentially reduce disease impact.

Adequate resources are required for eradication/containment.

The Australasian Plant Pathology Society (APPS) urges that the processes are set in place so that these funds can be made available immediately. A formal expert committee should be convened to provide considered advice.

The Australasian Plant Pathology Society (APPS), the lead organisation representing Australasian plant pathologists, recommends that necessary funding and urgent action be taken to:

   (i)        Strenuously attempt eradication of the incursion

   (ii)       Establish an expert committee to provide advice on how best to deal with the incursion

The APPS is concerned that action and responses to address the problem, and to alert authorities and interest groups to the potentially devastating consequences of the outbreak, have been insufficient for the eradication of this exotic disease.

We stand ready to help in whatever way we can.

As a contribution to boosting Australia’s responses, donations can be made to the Australasian Plant Pathology Society’s Advancing Plant Pathology Fund Australia at http://www.australasianplantpathologysociety.org.au/app_fund.html, or sent to the Australasian Plant Pathology Society, PO Box 4674, Toowoomba East, Queensland 4350, Australia.  Make cheques out to Advancing Plant Pathology Australia Fund. Donations of $ 2 or more are tax deductible.