Spider venom key to new insecticides
Maggots could be a lifeline for medics
police Senior VENOM from tarantulas caught within the Far North is used to develop environmentally safe insecticides.
Scientists from the University of Queensland are milking venom from featherleg spiders, also known as the Australian tarantula, caught from an area north of Cairns, to produce a potent chemical to kill insect pests.
The research is to be presented at the Australian Entomological Society Conference in Cairns today.
Dr Maggie Hardy, from UQ’s Institute for Molecular Bioscience, helped identify a toxin known as OAIP-1 that is lethal if eaten by termites and cotton bollworm.
She said the toxin had proven to be more potent against certain insect pests than existing chemical insecticides. “It makes sense that spider venoms contain potent insecticides, because spiders are expert insect killers, and have been for about the last 400 million years,’’ she said.
Concerns have been raised about the effect some current pesticides can have upon social insects such as bees, with scientists believing the chemicals could be interfering with the bees’ navigation systems.
This can lead to declines in bee populations, which could be disastrous for Australia’s agricultural industries.
Dr Hardy said the spider venom had been proven on a molecular level to be safer for bees and other ‘‘beneficial’’ insects, such as ladybugs, which prey on pest species.
It could also be produced on an industrial scale, at an affordable price.
“With pesticides, we’re trying to move towards a more environmentally sustainable set of controls, and make sure that they don’t kill a whole bunch Hardy said.
She said although the venom was originally trialled on subterranean termites, there was a broad range of insect pests it could be applied to, including paralysis ticks.
“It could be used in sugar cane, to target the cane borer,’’ she said.
“But the really tricky thing is where the borer lives, which is inside the sugar cane stalk.
“So really, it’s a penetration issue.”
Featherleg spiders are regarded as one of the largest species of Australian spiders, with their leg spans growing in excess of 16cm.
The burrowing arachnids flourish in dry open forests and deserts.
Dr Hardy said despite the spider’s size, they were challenging to milk, using a device to stimulate muscles in the creature’s body to encourage
of
stuff,’’ Dr it to produce venom. “The venom gland is just a sac, and it’s surrounded by muscles,’’ she said.
“And essentially when you apply that slight electrical stimulation to the muscles surrounding the venom gland, it causes the muscles to contract and push the venom out.
It doesn’t take huge amounts of time.
“But the tricky thing is their fangs are about 1cm long or more and they can rotate nearly 180 degrees backwards.
“So if you don’t get them properly, the fangs might get you – but I’ve never been bitten.”
DR MAGGIE HARDY