Knowing which termites are kin and where they’ve been may be
the key to more effectively controlling the pests. And scientists
are closing in. They’re using DNA technology to track their
travels
and find their family trees.

“I’m looking at what we call gene flow, which is the
genetic
relationship of one termite to another,” said Tracie
Jenkins,
a geneticist working in the University of Georgia’s entomology
department.

“DNA can be used to determine termite relationships just
as it is used to determine human relationships,” Jenkins
said. “It can also be used to track termite movement over
time.”

Atlanta and Louisiana Termites From Same
Family

Jenkins tested the
DNA of termites found at four sites in metro Atlanta. She found
that they came from Louisiana and traveled to Georgia inside
railroad
ties.

In her lab at the Georgia Experiment Station in Griffin, Ga.,
Jenkins examined a mitochondrial DNA gene from the Formosan
subterranean
termites, an imported species.

“The mitochondrial DNA gene is inherited from the female
line and therefore can be used to trace maternal movement,”
Jenkins said. “By comparing the Atlanta collections with
collections from many other sites in the Southeast and elsewhere,
I discovered a match with sites in Louisiana.”

Surveying the four Atlanta homeowners, Jenkins found they all
bought infested railroad ties for landscaping. “This study
demonstrates how interstate commerce can help spread
termites,”
she said.

As a result of the research, she said, the Railway Tie
Association
is alerting the railroad community to the possible problems of
spreading Formosan termites in crossties. And they’re taking
steps
to prevent it.

Jenkins’ genetic research is part of the UGA College of
Agricultural
and Environmental Sciences’ urban agriculture effort. By
understanding
termites’ family relationships and movements, she said, the
$2-billion-a-year
pest may be better controlled.

“You have to know your enemy before you can fight
him,”
she said. “You can’t treat for a creature if you don’t know
how it operates.”

Do Colonies Really Have Just One
Queen?

Jenkins said subterranean termite colonies are traditionally
described as having one king and one queen. The mated pair’s
mature
offspring fly away and start new colonies.

After studying termite sites across Georgia and the world for
the past five years with UGA urban entomologist Brian Forschler,
Jenkins isn’t sure she agrees with the one-king, one-queen
scenario.

At one termite site on Georgia’s Sapelo Island, Jenkins and
Forschler found termites of one species one month and another
species the next.

Jenkins’ research also provided DNA evidence that different
species traveled through the same site. Her DNA work uncovered
evidence, too, of four termite species at the site. Entomologists
knew three of those were in Georgia. But one is new to the
state.

“In this one study we determined they move rapidly when
they want to, different species can come in and occupy the same
site and there are most likely more than three species in
Georgia,”
she said. “This opened up a whole new research project for
me. I’m obsessed by what I’m learning.”

High Cost of DNA Sequencing Slows
Research

The only problems standing in Jenkins’ way are the numbers
of hours in a day and the high cost of DNA testing.

“I’d like to be able to run more DNA fingerprinting and
DNA sequences,” she said. “But DNA work, although
extremely
informative, is very, very expensive. So I have to design my
experiments
with cost in mind.”

Jenkins’ next steps are to find whether more than one queen
is in each colony and if different species coexist and feed in
the same site.

“Every day I’m ferreting out their biology and how they
work,” she said. “Termites are interesting creatures.
But because they’re a homeowner’s nightmare, I hope my work will
help in the fight to control them.”