With termite genome decoded, researchers aim for less toxic pest control
Their work reveals genetic clues about the insects' behavior, making it possible to target specific attributes.
Wed, May 21, 2014 at 12:22 PM
Photo: Tom Campbell, courtesy of Purdue University
Termites cause an estimated $40 billion in damage every year, including the costs to control them. But getting rid of termites often involves using great quantities of toxic chemicals, which can leave an unwanted legacy even greater than the holes the insects leave behind.
"While current pesticides are very effective products, the problem is that you're injecting large volumes of them into the soil around the house," says Purdue University entomology professor Michael Scharf. "It would be nice to move to a greener technology."
That might be possible thanks to the research of Scharf and his collaborators, who this week published the first sequenced genome for a termite species, the Nevada dampwood termite. The research was published May 20 in the journal Nature Communications, and the data set is also available through the project's website, termitegenome.org.
The research paper itself is titled "Molecular traces of alternative social organization in a termite genome." The researchers compared the genome of the Nevada dampwood termite with insects in the order Hymenoptera, which includes wasps, bees and ants. Like those other insects, the research reveals that termites are highly social creatures. For example, they carry the same genes that honeybees use to determine their caste system. The genes can be turned on or off by chemical tags, which then determine the role each individual insect plays in the greater colony.
Scharf says this and other information revealed in the sequenced termite genome could allow researchers to develop less toxic treatment alternatives that would target specific genes and therefore specific behaviors. "Depending on which gene or protein that is targeted, we could disrupt termites' neurological processes, molting, digestive factors or cuticle formation. We're just limited by our imagination," Scharf said in a news release.
The advantage of this genetic targeting is that, theoretically, you wouldn't have to try to poison an entire termite colony to wipe it out. For example, small quantities of wood could be treated with a specific chemical. A few termites would eat the wood and carry its back to their colony, disrupting the entire group. "With termites, you don't have to impact all of them," Scharf said. "Targeting just a fraction of the workers could cause an entire colony to collapse."
The research also found that dampwood termites, like ants, have a large number of genes that function in immune responses, a necessary adaptation for social species that live in densely populated colonies. Unlike ants, however, they have fewer olfactory receptors. This may be because of their particular behavior: this particular species tends to find a piece of wood and stay there rather than continually finding new food sources.
The Nevada dampwood termite is not much of a threat to buildings, but it is closely related to other pests that create a lot of damage, such as the eastern subterranean termite.
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