Locust plagues are a major threat throughout the world. A swarm of locusts can devastate crops and cause considerable agricultural damage, potentially leading to famine and starvation. In Africa, locusts are the single most destructive force on subsistence farming. Could the same chemical released by locusts to prompt them to swarm also help to control the flying pests?
Researchers from China think so. Scientists from the Chinese Academy of Sciences in Beijing have discovered an airborne chemical pheromone they believe is responsible for encouraging swarming behavior. In laboratory experiments, the investigators found that this chemical, 4-vinylanisole, is emitted by the most widespread species of locust found in Africa, Asia, Australia, and New Zealand. They also ascertained the particular spot on locusts’ antennae where their olfactory receptors are located. This chemical secreting and sensing ability is thought to be responsible for attracting other locusts in the wild, triggering the swarming behavior that is so well known (and feared) by farmers.
“Both gregarious and solitary locusts are strongly attracted to 4VA, regardless of age and sex,” the researchers write in an abstract for their work. “Although it is emitted specifically by gregarious locusts, 4VA production can be triggered by aggregation of four to five solitary locusts. It elicits responses specifically from basiconic sensilla on locust antennae.”
This discovery is of interest to those who study locusts, but how do the researchers think it could help to prevent future swarms of locusts? Simply put: It could be used to create sticky traps that will attract locusts. Once they are there, they could then be more effectively neutralized using insecticides. Another possible solution would involve finding a way to stop the locusts’ 4-vinylanisole receptors from detecting the 4VA pheromone. This could stop them from being encouraged to swarm altogether.
Locusts aren’t entirely useless, however. Digital Trends has previously covered a project sponsored by the Office of Naval Research in which backpack-sporting remote-control cyborg locusts (yes, really!) are used to sniff out explosive chemicals. That particular project is ongoing.
A paper describing this latest pheromone-related project, titled “4-Vinylanisole is an aggregation pheromone in locusts,” was recently published in the journal Nature.