Feb. 18, 2005. 06:28 AM
Come-hither attractant identified
Come-hither attractant identified
Could lead to new way to control pests
PAUL RECER
PAUL RECER
ASSOCIATED PRESS
WASHINGTON—Blatellaquinone.
It's not exactly a name that would send you scurrying for the nearest perfume counter — unless, of course, you're a cockroach.
Specifically, a male German cockroach.
And then it could be the death of you.
At least, that's what scientists are hoping now that they've managed to identify the "come hither" scent that female German cockroaches use to lure males.
The German cockroach, one of the world's most troublesome and resistant household pests — and the bane of many a Toronto apartment dweller — has, until now, been able to laugh off attempts to, well, poison it, because no one quite knew how.
"The German cockroach is the one we wanted because it is a worldwide pest that gives all the other cockroaches a bad name,'' said Wendell Roelofs, a Cornell University entomologist and senior author of a study appearing this week in the journal Science.
Female cockroaches emit a pheromone, or chemical attractant, to let males know they are ready to mate, and while researchers earlier identified the courtship chemicals used by other cockroach species, the romance scent of the German cockroach remained elusive.
Roelofs said scientists for years could not even identify the gland the female German cockroach used to store and secrete the pheromone. And when the bug did send her mating signal, the chemical was in too small a quantity to be detected and isolated by researchers in the lab.
In 1993, Coby Schal of North Carolina State University, Raleigh, a co-author of the study, identified the bug's pheromone gland and sent cells to the Cornell lab. But Roelofs said his team found that the chemical compound in the gland was too heat-sensitive to analyze using gas chromatography, a technique in which the specimen is heated and the compounds are collected and sequenced as they evaporate.
Roelofs said a graduate student in his lab, Satoshi Nojima, developed a low-temperature technique that allowed the chemicals in the mating lure to separate into compounds and then let the male bug show them which compound was the actual fragrance of insect love.
The researchers removed an antenna from a male German cockroach and attached two electrodes to it. The antenna was then exposed to the flow coming from the low-temperature chromatograph loaded with pheromone.
"The male antenna is the only detector in the world that could tell us which compound is active for that species," said Roelofs.
Roelofs said the antenna, which remains alive for hours after removal from the insect, reacted only to a specific chemical compound in the pheromone, thus allowing the researchers to isolate and identify the attractant.
"When a compound elicited a big response from the antenna, then we knew we had it," he said.
The researchers named the pheromone "blatellaquinone," from the scientific name of the German cockroach species, Blatella germanica.
Roelofs said the pheromone has now been synthesized and tested on male cockroaches. The male bugs love it, he said.
The discovery may lead to a new weapon to control the German cockroach, an insect that is a resistant and tenacious pest in virtually every city on Earth.
Fossil records indicate that cockroaches have inhabited Earth for at least 200 million years. They are low-maintenance creatures and can survive in a wide range of environments. They can eat almost anything, including linens, cardboard, leather and book bindings, and are widely believed capable of surviving nuclear war.
Roelofs said the pheromone could be used to attract males to sticky traps or to poisoned baits that the insect would then carry back to other cockroaches. He said Cornell has patented the chemical and would receive money if pest control companies use the pheromone.
It's not exactly a name that would send you scurrying for the nearest perfume counter — unless, of course, you're a cockroach.
Specifically, a male German cockroach.
And then it could be the death of you.
At least, that's what scientists are hoping now that they've managed to identify the "come hither" scent that female German cockroaches use to lure males.
The German cockroach, one of the world's most troublesome and resistant household pests — and the bane of many a Toronto apartment dweller — has, until now, been able to laugh off attempts to, well, poison it, because no one quite knew how.
"The German cockroach is the one we wanted because it is a worldwide pest that gives all the other cockroaches a bad name,'' said Wendell Roelofs, a Cornell University entomologist and senior author of a study appearing this week in the journal Science.
Female cockroaches emit a pheromone, or chemical attractant, to let males know they are ready to mate, and while researchers earlier identified the courtship chemicals used by other cockroach species, the romance scent of the German cockroach remained elusive.
Roelofs said scientists for years could not even identify the gland the female German cockroach used to store and secrete the pheromone. And when the bug did send her mating signal, the chemical was in too small a quantity to be detected and isolated by researchers in the lab.
In 1993, Coby Schal of North Carolina State University, Raleigh, a co-author of the study, identified the bug's pheromone gland and sent cells to the Cornell lab. But Roelofs said his team found that the chemical compound in the gland was too heat-sensitive to analyze using gas chromatography, a technique in which the specimen is heated and the compounds are collected and sequenced as they evaporate.
Roelofs said a graduate student in his lab, Satoshi Nojima, developed a low-temperature technique that allowed the chemicals in the mating lure to separate into compounds and then let the male bug show them which compound was the actual fragrance of insect love.
The researchers removed an antenna from a male German cockroach and attached two electrodes to it. The antenna was then exposed to the flow coming from the low-temperature chromatograph loaded with pheromone.
"The male antenna is the only detector in the world that could tell us which compound is active for that species," said Roelofs.
Roelofs said the antenna, which remains alive for hours after removal from the insect, reacted only to a specific chemical compound in the pheromone, thus allowing the researchers to isolate and identify the attractant.
"When a compound elicited a big response from the antenna, then we knew we had it," he said.
The researchers named the pheromone "blatellaquinone," from the scientific name of the German cockroach species, Blatella germanica.
Roelofs said the pheromone has now been synthesized and tested on male cockroaches. The male bugs love it, he said.
The discovery may lead to a new weapon to control the German cockroach, an insect that is a resistant and tenacious pest in virtually every city on Earth.
Fossil records indicate that cockroaches have inhabited Earth for at least 200 million years. They are low-maintenance creatures and can survive in a wide range of environments. They can eat almost anything, including linens, cardboard, leather and book bindings, and are widely believed capable of surviving nuclear war.
Roelofs said the pheromone could be used to attract males to sticky traps or to poisoned baits that the insect would then carry back to other cockroaches. He said Cornell has patented the chemical and would receive money if pest control companies use the pheromone.
1 comment:
Die roaches! Die! Wahahahaha!
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