Gene-silencing Technique to be Deployed against Soybean Fungus
By Jan Suszkiw
November 5, 2008
The soybean rust fungus Phakopsora pachyrhizi may meet its
match, thanks to a gene-silencing technique that scientists of the
Agricultural Research Service (ARS) plan
to deploy to identify genes that enable plants to naturally resist this fungal
Pedley, at the ARS
Disease-Weed Science Research Unit at Fort Detrick, Md., will use gene
silencing to discover plant genes that play a role in orchestrating defense
responses to P. pachyrhizi in resistant soybeans. The fungus causes
substantial losses to soybeans worldwide, and its September 2004 detection in
the continental United States has accelerated efforts to protect the $18
billion U.S. soybean crop.
Gene silencing allows scientists to identify a gene's function by
disabling that gene in plants or other organisms, challenging the organism in
some waysuch as with exposure to a pathogenand observing the
consequences that result from that gene having been "missing in action." In
Pedley's studies, the gene-silenced plants will be inoculated with spores of
P. pachyrhizi, and monitored for a breakdown in resistance.
Pedley's research plan was the top-ranked in a total of 450 proposals
recently submitted to the ARS Postdoctoral Research Associate Program. In honor
of his top ranking among the proposals, Pedley has received the agency's T.W.
Edminster Award, named for a former ARS administrator, plus $120,000 to fund a
postdoctoral associate position for two years.
The ultimate goal of Pedley's research is to streamline the
development of new soybean cultivars that can withstand P. pachyrhizi,
which causes a foliar disease that severely weakens the plant and diminishes
its seed yields and quality. Pedley is collaborating with
Iowa State University scientists, and
this award will expand upon those efforts.
ARS officials also selected 50 other research proposals for two years
of funding at $100,000 per proposal under this year's Postdoctoral Research
Associate Program. Other plans approved for funding include research on
development of molecular-based pesticides for control of varroa mites in honey
bees, methods to produce antimicrobial cotton wipes, use of remote sensing to
monitor rangelands, and replacing fish meal with grain-protein concentrates in
feed for Atlantic salmon production.
ARS is a scientific research agency of the
U.S. Department of Agriculture.