RESEARCH
(L to R) Amir Abdullah,
Mike Adang, Gang Hua and
Jiang “John” Chen continue
work on BtBooster at their
UGA lab.
‘Failed’ Experiment Changes the
Future of Biological Pesticides
By Stephanie Schupska
The experiments had gone terribly awry. Mike Adang had
expected the hornworms to be ready and waiting to devour
more plants. They weren’t supposed to have died.
But to Adang, an entomology professor with the University
of Georgia College of Agricultural and Environmental Sciences,
there is no such thing as a failed experiment. What he had,
instead, was a “eureka” moment.
By adding a bit of an insect protein to a small piece of
Bacillus thuringiensis (Bt) protein, he learned that it “took less Bt
to kill the insects.”
Bt produces proteins that are toxic to many insect species.
“It’s a natural bacterium,” Adang said. “It attacks the insect’s gut,
making the insect sick.”
However, some insects are resistant to Bt. And that’s where
Adang’s surprise comes into play.
He and colleagues Gang Hua and John Chen had been
hoping to learn how Bt kills insects by feeding them part of an
12 • SOUTHSCAPES • FALL 2006
insect protein, the Bt receptor.
Instead, they found a way to
supercharge Bt and kill the
insects faster and with less
biopesticide.
And BtBooster was born.
“We were very pleased to
see something come from our
basic research,” Adang said.
“It’s a long way from the lab to
making something useful.”
Bt proteins have changed the
way crop plants are protected
Hornworm
against insects. The technology
can be built into a plant like cotton or corn and has been
available to farmers since 1996. Vegetables and trees can also
be protected from insect damage by being sprayed with a
PHOTOS.COM
STEPHANIE SCHUPSKA
STEPHANIE SCHUPSKA
John Chen, left, and Gang Hua explain the differences in hormworm growth as the
insects are exposed to different plant material. In the photo on the left, the insects at
the bottom right square are the control insects. The hornworms in the square above
have been feed Bt and are slightly smaller but still alive. The insects in the bottom
left square have been treated with BtBooster and are either dead or dying.
biopesticide made from Bt.
Bt provides an alternative to chemical ways of dealing with
pests, especially where chemicals could harm humans. Bt
doesn’t hurt people. For that reason, foresters can spray whole
stands of tree with Bt to fight gypsy moths, which are among
North America’s most devastating forest pests.
Organic farmers can use Bt and still be considered organic
farmers because biopesticides come from living organisms. They
can control the insects on their crops without having to worry
about chemical residues.
Insects eat one-third of all food produced worldwide before
it ever reaches the dinner table, Adang said. “Insects need to be
controlled in order to have a successful crop,” he said.
Though Bt crops are becoming more common, chemicals
are still a common way of controlling insects. “Chemical
pesticides are still safe,” Adang said. “But over the years,
people have started to worry more about problems such as
groundwater contamination and other issues like that.”
Through Bt, and now with BtBooster, the potential impact
is great as more producers use crops that have been retrofitted
with the Bt protein.
“Using BtBooster will allow Bt crops and Bt biopesticides
to work better,” Adang said, “having a positive environmental
impact and reducing chemical insecticide use.”
Adang has been collecting insects since he was a boy. At 8
or 9 years old, he was even on Saturday morning TV with his
insect collection he said.
As an undergraduate at Indiana University, he got interested
in how microbes are used for practical things such as bioremediation, which breaks down toxic compounds in contaminated
areas. He then learned that microbes can be used to kill insects.
“I’ve always been interested in alternative methods for insect
control,” he said. “I do favor safer ways to kill insects. Basically,
my whole career is centered on this aspect of insect control.”
The concept of developing plants naturally resistant to
insects intrigued him. In 1989, he came to the CAES hoping to
answer some basic questions on why Bt kills some insects and
not others and how insects become resistant to biopesticides.
Through a National Institutes of Health grant, UGA and his
gene design and discovery company InsectiGen, Adang is now
studying how Bt kills mosquitoes, especially those that carry
diseases like West Nile virus.
“We’re looking at mosquitoes worldwide,” he said,
“mosquitoes that vector dengue fever and other diseasetransmitting mosquitoes. Over the long term, we want to make
Bt more effective at killing mosquitoes.”
Using a U.S. Department of Agriculture National Research
Initiative grant, he’s also specifically looking at how insects
become resistant to Bt in cotton. He’s digging deeper into the
workings of BtBooster, too, trying to figure out how it works and
making improvements to optimize it.
Through UGA’s Georgia BioBusiness Center, Adang formed
InsectiGen in 2003 with Clifton Baile, a distinguished professor
and Georgia Research Alliance Eminent Scholar in Agricultural
Biotechnology. Its focus is on discovering and engineering
proteins for insect control.
Because of his discovery of BtBooster, he was presented
the UGA Inventor’s Award on March 29. He has also filed for
a patent license to continue his quest of developing a farmproduction product for pest control.
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