DEADLY NEW ATTACK ON TASSIE WILDERNESS

Giant Eucalyptus trees could be at a risk.

It turns out the logging and paper industry is the not the singular most dangerous threat faced by trees in the Tasmanian wilderness. The discovery of a devastating plant disease in Tasmania, which could wipe out large areas of the state’s wilderness and forestry reserves, has triggered a biosecurity emergency. As interest groups try to reach the decision as to whether to allow tourist projects in sensitive wilderness areas, a breach of the state’s biosecurity protocols has the potential to have a great effect on the tourism and forestry industries and hurt small business operators such as nurseries and landscapers.

The myrtle rust disease has reached Tasmania. Though experts believe the disease has been in Tasmania for a little over two months, it has already been confirmed in 15 properties around the state, the affected plants all being lophomyrtus.

Uredo rangelii, commonly known as Myrtle Rust, is a fungal plant pathogen native to South America that affects plants in the family Myrtaceae. Myrtle rust was first recorded in Australia in mid-2010 and currently poses a major threat to the continent's ecosystem given that almost 80 per cent of Australian native trees are Myrtaceae, most indigenous species rely on healthy trees for their survival. Additionally it poses a major threat to Australia's primary industry sector. Its current range includes much of the eastern coastal fringe of the Australian mainland.   The disease attacks a wide range of plants, from natives such as eucalyptus, paperbarks and tea-trees, to garden favorites like bottlebrush and lophomyrtus. About 300 native species have been proved susceptible but many more of the 2250 ­native plants in the family could also be at risk. At least two species of ­native plants (scrub turpentine and native guava) on the mainland have already undergone a catastrophic decline as a direct result of myrtle rust. Both of those species were widespread in eastern mainland Australia and before 2010 were regarded as of no conservation concern. The disease results in a high degree of pustule coalescence which can result in distortion of the leaf. Myrtle rust also makes plants more susceptible to secondary infections, which may occur within days of the initial appearance of the pustules.

Plant affected by Myrtle rust disease.

In Tasmania, an incident control center has been set up to tackle the disease, and more reports from the public are being investigated. The cause of myrtle rust’s arrival in Tasmania is unknown but theories include its transportation on a bushwalker’s gear. The disease produces a huge number of spores that can survive on the wind, clothing or vehicles. Tasmania restricts the importation of myrtles but illegal plant movement is not being ruled out.

The New South Wales government spent $5 million attempting to eradicate the disease. However, efforts to contain it failed and it spread rapidly north and south along the eastern coast. In response to the increasing threat, a Myrtle Rust National Management Group was formed on 2 July 2010 with the aim of eradication however due to the extent of its spread at that point of time, the group conceded that it had become impossible to eradicate. The original plan to eradicate myrtle rust in Australia was declared to be infeasible by the Myrtle Rust National Management Group in December 2010. The Myrtle Rust Response Plan was cancelled and focus was placed on minimizing the spread and the impacts on myrtle rust. The Australian Government established the Myrtle Rust Coordination Group to manage the investment of $1.5 million of research funding into the control of and propagation of the disease-resistant strains.

There is still hope for the complete eradication of the myrtle rust disease in Tasmania because of its early detection as compared to the other states.

By Edwina Owusu-Adjapong

 References: http://news/tasmania/deadly-new-attack-on-our-wilderness/story-fnj4f7k1-1227243062809

http://en.wikipedia.org/wiki/Uredo_rangelii