Raspberry Virus May Thwart
By Kathryn Barry
October 19, 2000
Consumers, growers and the
environment would benefit if raspberry plants could naturally resist bushy
dwarf virus. Scientists with ARS in
Corvallis, Ore., and Agritope, Inc., in
Portland, are genetically modifying the most popular raspberry variety grown in
the Pacific Northwest to give the plants this resistance.
Raspberries with the virus develop small, crumbly fruit that is unsuitable
for use as whole berries. The infection spreads rapidly through a field, and
growers must frequently remove the plants, fumigate the soil and start over
within five years. That means fewer domestic raspberries and higher costs for
The scientists are using the genetic material from the virus itself to
induce resistance in the raspberry plants. They're trying three strategies to
find the best approach. The first interferes with the virus' ability to
replicate by inserting a specific protein from the virus into the raspberry.
A second approach is to alter the viral gene that makes it possible for the
virus to move from cell to cell inside the plant, and then insert that altered
gene into the raspberry plants. With this altered gene present in the plant,
the virus would able to infect one cell of the plant, but couldn't spread to
any other cells.
The third method they're trying is to have the plant make a small piece of
viral RNA, or genetic material, that does not make any protein. Through a
natural plant mechanism, this viral RNA then gets targeted by the plant for
They hope to refine the best strategy and provide breeding lines to growers
within three years. They should also be able to use the results to incorporate
virus resistance into other cultivars of raspberry, blackberry or black
An article on this research appears in the October issue of Agricultural Research, the
agency's monthly magazine.
ARS is the chief research agency of the U.S.
Department of Agriculture.
Scientific contact: Robert R. Martin, ARS
Crops Research Laboratory, Corvallis, Ore., phone (541) 750-8794, fax (541)