GAINESVILLE, Fla. — Hungry Formosan termites farm antibiotics from their homes, which they make from their own recycled fecal waste, new University of Florida research shows. These beneficial bacteria make the destructive bugs immune to natural control methods.
If termites cannot be controlled with biological methods, property owners must use sprays or baits to keep the bugs at bay.
Formosan subterranean termites eat away at houses and businesses. In fact, Formosan and Asian subterranean termites, combined, are responsible for most of the $32 billion in economic damage to structures worldwide, UF Institute of Food and Agricultural Sciences researchers say.
For more than half a century, researchers have tried to use natural methods as biological controls against termites, said Thomas Chouvenc, a UF/IFAS assistant professor of entomology. Under ideal circumstances, scientists would want to use biological control – “good bugs eating bad bugs” – to keep termites in check.
But biological control has failed, and now scientists know why.
“Termites have a social immunity,” said Chouvenc, a faculty member at the UF/IFAS Fort Lauderdale Research and Education Center. “As social insects, they evolved disease resistance mechanisms that prevent harmful microbes from taking over their colonies.”
One aspect of this resistance is the termites’ ability to farm antibiotics from their fecal nest, by hosting Streptomyces, a beneficial bacteria.
However, the UF/IFAS research team led by Chouvenc discovered that termites are incapable of retaining their association with the good bacteria across generations. But that’s because they don’t need to, Chouvenc said. Good microbes live everywhere in the soil, and termites go out and bring them back into their fecal nest to farm antibiotics, he said.
As a result, the beneficial microbes keep the termites alive and healthy, which further reinforces why scientists and exterminators cannot use natural methods to kill termites, Chouvenc said.
It may also explain why the Formosan subterranean termite is such a successful invasive species, he said. These termites may easily adapt to a new environment by taking advantage of local beneficial microbes in the soil against naturally occurring harmful pathogens.
About five years ago, Chouvenc led a study that showed that termites can grow Streptomyces in their feces, as a case of what scientists call “mutualism.” In this case, researchers see “mutualism” when termites use their feces as a food source for the good bacteria, and in return, the good bacteria provide antibiotics to the termite colony against pathogens. Until now, researchers did now know the source of these good bacteria.
“Most studies on other social insects suggested that similar beneficial symbiotic microbes are inherited from the parents, resulting in an elegant case of co-evolution,” Chouvenc said. “However we realized that in the case of the Formosan subterranean termite, they actually go in the soil, and just recruit the good microbes locally.”
The study is published in the journal Environmental Entomology.
By: Brad Buck, 352-294-3303, email@example.com
The mission of the University of Florida Institute of Food and Agricultural Sciences is to develop knowledge relevant to agricultural, human and natural resources and to make that knowledge available to sustain and enhance the quality of human life. With more than a dozen research facilities, 67 county Extension offices, and award-winning students and faculty in the UF College of Agricultural and Life Sciences, UF/IFAS works to bring science-based solutions to the state’s agricultural and natural resources industries, and all Florida residents. Visit the UF/IFAS web site at ifas.ufl.edu and follow us on social media at @UF_IFAS.