Termites are social insects that feed on material containing cellulose, including wood. By one estimate, termites cause $30 billion a year in damage to structures worldwide, plus more spent on pesticides to get rid of them.
Now, American researchers have stumbled on something that may lead to a method of killing termites in a potentially more benign way.
Our termite control arsenal now consists mainly of toxic chemicals - pesticides that can have collateral damage, harming other animals, including humans.
"So the current techniques are to put some of these chemicals in barriers around households where they can leach into the groundwater," says Mark Bulmer, who studies termites.
He writes about his latest research this week in the Proceedings of the National Academy of Sciences. He's now at Towson University, but his paper is based on work he did at Northeastern University in Boston, along with colleagues from Massachusetts Institute of Technology.
Studying the insects in the lab, Bulmer found termites have natural resistance to a fungus that would otherwise be deadly to the bugs, but a kind of sugar can undermine that natural protection.
"What we basically found is they're producing these enzymes that are able to chew up a component of the fungal cell wall, and a small sugar called Glucono delta-lactone [GDL] could inhibit these enzymes," Bulmer explains. "And that would prevent the enzymes from chewing up the fungal cell wall and, therefore, make the termite vulnerable to fungal pathogens."
So instead of poisoning the termites with toxic chemicals, you could feed them this sugar. It's not the same sugar we use to sweeten our coffee or tea, but it is already used as a food additive, and it occurs naturally in other foods such as wine and honey, so it shouldn't hurt humans or other organisms.
So far this is just a laboratory finding, but in an interview, Bulmer suggested that the sugar and the fungus could be combined into a tempting food that would attract termites and kill them before they could do damage.
"One idea is that you could actually design a bait for termites, a food source that termites would access, and they would be exposed to, say, a fungal pathogen that you put in this bait, and you also include in the bait this sugar that basically prevents them from destroying the fungus with their immune system."
Again, Bulmer stressed that he hasn't confirmed this out in the real world.
"We haven't tested it in the field. We've just done this in the lab. And it works in the lab in that you can feed termites this sugar, and they become more vulnerable to the fungal pathogens. In the real world, it's a lot more complex, obviously, and we have not actually tested this in the field."
Mark Bulmer says his co-authors from MIT will be taking the next step, bringing this discovery out of the laboratory and trying to find the best way to use this discovery to actually control wood-eating termites and take a bite out of that estimated $30 billion in damage they cost each year.