“There is an urgent need for new insecticides due to insects becoming resistant to existing products and others being deregistered due to perceived ecological and human health risks,” says Prof Glenn King of the University of Queensland’s Institute of Molecular Bioscience.
Spider venoms contain hundreds of toxins, and each species is different. However, only orally fatal insecticides are of much use. Topical toxins are usually equally damaging to non-target species, including important pollinators like bees.
Dr Maggie Hardy, who had been completing a PhD under King, identified the toxin OAIP-1 and demonstrated that it is orally effective against termites and cotton bollworms. “Cotton bollworms cause major economic damage to crops, and the toxin we have isolated is more potent against these insects than existing chemical insecticides,” says King, who published the research in PLoS One.
“From an evolutionary perspective it is a little surprising a spider toxin is orally active, but from a biochemistry point of view it is not surprising at all,” Hardy says. “These sorts of peptides are very thermally and chemically stable.” Consequently, they survive in the insect’s digestive system.
Hardy is planning to test OAIP-1 against non-target species, and has high hopes. “These chemicals are like table salt to vertebrates – they’re bad for you only in...
