Exploding pineapples and biosecurity

There is a bit of a stoush going on in pineapple land. Last June the Department of Agriculture, Fisheries and Forestry (DAFF) Biosecurity recommended that the import of fresh pineapple fruit to Australia from Malaysia be permitted subject to a range of quarantine conditions.

Now, obviously this was not popular with Australian pineapple growers who see their livelihood threatened by the imports. But this isn’t the usual “protect the local industry” hubbub, because DAFF determined that the only biosecurity risk from the imported pineapples was from four different types of mealy bugs. DAFF further determined that this risk was low and could be ameliorated by methyl bromide fumigation and inspection of incoming decrowned pineapples.

However, this opinion is at odds with Biosecurity Queensland. This organisation believes that the biosecurity risk of bringing Malaysian pineapples into Australia is actually quite “high”. Furthermore, they believe the risk organism is not DAFF’s mealy bugs but the gram-negative bacillus Erwinia chrysanthemi.

This bacterium causes Pineapple Heart Rot disease which can result in fruit collapse and exploding pineapples. When the Hawaiian pineapple industry was affected by this disease in 2003 up to 40% of some crops were wiped out.

Biosecurity Australia found that up to 2% of every pineapple shipment from Malaysia could be infected and it is known that the bacterium is very hard to detect in its latent phases.

In 2008, Plant Health Australia collaborated with the pineapple industry and government stakeholders to develop a National Biosecurity Plan for the pineapple industry. First plant pests were identified, and then their potential threat, based on entry, establishment, spread and economic criteria, was assessed. These high-priority pests provide a focus for further risk-mitigation activities such as surveillance, on-farm biosecurity and awareness activities. Three invertebrates and two pathogens were determined to be ‘High Priority Emergency Plant Pests’ for the pineapple industry. Erwinia chrysanthemi was one of the two pathogens identified.

So, who is right? Should we be concerned about Malaysian pineapples?

Senator for Queensland Ron Boswell is. Partly at his instigation, the Senate Rural and Regional Affairs and Transport References Committee report into the effect of imported fresh pineapples from Malaysia has been delayed to allow the Committee to obtain independent analysis of the risk estimation matrix used by Biosecurity Australia in their decision-making regarding foreign imports.

Perhaps more to the point, should we be concerned about the ‘risk estimation matrix’ DAFF uses? Certainly we should be able to be confident that we are getting these assessments right. After all, we have a rather murky history of getting them wrong - remember how cane toads were going to rid the sugar industry of pests?