more detailed story about the work in the Agricultural Research.
Bad Virus Put to Good Use in Lab
December 1, 2000
A plant virus that normally causes disease in wheat crops may
actually do some good for a change--as a biotech tool in the laboratory.
The wheat streak mosaic virus (WSMV), spread by wheat curl
mites, can cause large crop losses at its worst, like the outbreak which cost
Montana growers $35 million in 1995.
Since then, however, an Agricultural Research Service and
University of Nebraska team
has decoded the genetic secrets behind WSMVs costly ability to destroy
wheat. They have charted all 9,384 of the chemical letters, or nucleotides,
comprising the virus genetic code. In the process, the researchers
identified gaps in the virus genetic code where new information could be
inserted, such as adding genes for proteins or traits that would actually
benefit wheat plants.
ARS plant pathologist Drake Stenger says their approach uses the
altered virus as a vector for delivering and expressing introduced
genes into grown wheat plants. Then they can examine what these viral-borne
genes do, and for how long. The scientists can also gauge how these genes will
affect plant tissues much more quickly than if they introduced the traits
through traditional breeding or even conventional genetic engineering. That
could help biotechnologists save time when they screen for genes that control
traits like improved nutrition, higher yield, better stress tolerance, or pest
resistance, says Stenger, who is at ARS
and Forage Research Unit in Lincoln, Nebraska.
So far, the Lincoln team has only modified the virus with two
bacterial enzymes for proof-of-concept purposes, but other genetic
payloads are planned. One goal is discovering proteins that could
ultimately help wheat plants inhibit other disease pathogens from replicating.
Once perfected, researchers will transfer the technology to commercial wheat
breeders, who can then adapt it for engineering new varieties with desirable
new traits that might not otherwise be possible through conventional
A more detailed story about the work appears in the December
issue of Agricultural
Research, ARS monthly publication.
ARS is the U.S. Department of
Agricultures principal scientific research agency.
Scientific contact: Drake Stenger, ARS Wheat, Sorghum and
Forage Research Unit, Lincoln, Neb., phone (402) 472-3166, fax (402) 472-4020,