Helpful Wasp Recruited to Fight Cotton Pest
November 5, 1997
A pinhead-sized wasp may help cotton plants battle one of their worst insect
enemies, the cotton aphid. Scientists with the
Agricultural Research Service have
recruited the shiny black wasp, Lysiphlebia japonica
(lye-suh-FLEA-bee-uh juh-PON-ih-cuh), for an outdoor experiment in California's
San Joaquin Valley.
A female L. japonica wasp attacks the cotton aphid as the pest feeds.
She jabs the aphid with her stinger-like ovipositor, then pumps a whitish egg
into the doomed insect. The egg hatches and becomes a larva that feeds on the
aphid's innards, killing it. Later, the wasp emerges as a winged adult.
L. japonica is harmless to humans and animals, according to ARS plant
pathologist Raymond K. Yokomi at the
Research Laboratory, Fresno, Calif. Yokomi is working with scientists at
the ARS Western Integrated Cropping
Systems Research Unit, Shafter, Calif.; the
California Department of Food and
Agriculture and the University of California
Cooperative Extension Service. The California Cotton Pest Control Board
funds part of the research.
To start their wasp colonies, the researchers used insects from ARS
Research Laboratory, Orlando, Fla., where scientists are scrutinizing the
wasp's ability to fight citrus pests. Formerly at Orlando, Yokomi was first to
import the Asian wasp into America for testing as a biocontrol. He and
colleague Yuqing Tang at Orlando were first to determine how to raise it
indoors for outdoor use.
The cotton aphid and other aphids cost California cotton growers more than
$11 million in l996. Cotton aphids feed on sap and excrete sticky honeydew that
contaminates cotton fibers. Sticky fibers may jam cotton gins or equipment at
Scientific contact: Raymond K. Yokomi, USDA-ARS Horticultural Crops
Research Laboratory, 2021 So. Peach Ave., Fresno, CA 93727-5951, phone (209)
453-3021, fax (209) 453-3088, e-mail firstname.lastname@example.org