Contributed by Roger Day, CABI
Ants farm bugs like people farm cows. So said Dr Ben Hoffmann of CSIRO, Australia, who led the Tuesday evening seminar at the 11th Session of the Commission for Phytosanitary Measures (CPM) on invasive ants. That’s why they’re a problem in agriculture. They protect and encourage other pests like mealy bugs, which reduce crop production and have to be controlled. Some ants have a painful burn-like sting, so are aptly known as fire ants.
By hitchhiking on shipped goods, hundreds of ant species have found their way to countries outside their native range. The costs to agriculture of these invasions are often not accurately quantified. But figures from US, for example, suggest ants cost them billions of dollars a year in damage and control costs. And Australia has spent hundreds of millions to eradicate fire ants – money well spent when the potential costs of uncontrolled spread are calculated.
Climate change is likely to affect which species of ants are problematic where, causing more headaches for farmers worldwide. Islands and developing countries, who can least afford the costs, are predicted to suffer most. Unfortunately many control methods currently rely on pesticides, although poisoned baits use relatively small amounts of chemical.
A potential new approach for controlling ants is RNA interference. The technique is still its infancy, but Dr Hoffmann predicted that ants will be among the first targets. Regulatory as well as technical issues will need to be addressed if the approach is to become widely used.
The presentation from this and other CPM Side Events will be available on the Phytosanitary Resources site.