The western tarnished plant bug feeds on several
important crops. Research shows that using certain volatile compounds could
improve biological control of the pest. Photo by Jack Kelly Clark, courtesy
University of California Statewide IPM
To Catch a Pest, Scientists Fine-Tune Traps
November 28, 2006
Airborne volatile compounds that
attract plant-feeding insects to alfalfa could help growers control cotton
pests with fewer pesticides.
That's according to Agricultural Research Service (ARS) entomologists
Byers, at the agency's
Arid-Land Agricultural Research Center in Maricopa, Ariz.
Working with Cesar Rodriguez-Saona of Rutgers University, they investigated the
influence of volatilesor chemical scentson the western tarnished
plant bug (WTPB), a pest that feeds on several important crops, including
Existing control options are extremely limited. Traps can be helpful pest
management tools, but their success hinges on knowing exactly how to lure a
particular insect. Often, that means enticing them with chemical signals, such
as sex pheromones, but researchers have not yet developed an effective WTPB
So what else attracts these insects? What kind of "carrot" could
draw them into a sticky trap?
The scientists' studies show that female WTPB are drawn to alfalfa volatiles
and chemically manufactured synthetics that have most of the characteristics of
natural chemical scents. This information could be used to develop more
effective field traps baited with volatiles.
Volatiles can add flavor to food, and fragrance to perfumes and scented
cosmetics. Plants use them to attract and repel insects, but insect responses
to them vary.
Another study combined the chemical cues with a green-light-emitting diode
(LED), which imitated a visual cue that attracts plant-feeding insects. Alone,
the LED drew several females, but when combined with volatile or synthetic
cues, it attracted both males and females at all stages of maturity. In some
tests, the LED-synthetic compound combination drew positive responses of 80
percent or higher.
In field tests, one chemical compound proved to be particularly promising at
drawing WTPB to the traps. Although the traps currently capture some beneficial
insects as well, the scientists hope further research will allow them to
develop a more target-specific model.
ARS is the U.S. Department of
Agriculture's chief in-house scientific research agency.