Renamed Laboratory Helps California Rice
By Kathryn Barry
January 21, 2000
California rice growers can reduce
threats to their crop yield from excess salinity thanks to guidelines developed
by scientists with the Agricultural Research
Service and the University of California Cooperative Extension Service.
Researchers at ARS' George E. Brown,
Jr., Salinity Laboratory in Riverside, Calif. contributed to studies
showing that rice yields were more sensitive than previously thought to
The laboratory has operated in Riverside for more than 60 years, the last 5
years in a new facility on the University of California campus. The Salinity
Laboratory is being renamed by the U.S.
Department of Agriculture for the late Congressman Brown in a ceremony
today at the lab. ARS is the USDA's chief research agency.
In California, rice is grown in fields with water flooded throughout a
series of adjacent basins. California ranks third in U.S. rice production
behind Arkansas and Louisiana. In 1999, more than one-half million acres were
State regulations require that water be held in these basins for a certain
period of time to allow pesticides used by rice farmers to degrade before the
water is released into local waterways. In drought years, if the water is held
too long, evaporation can concentrate salts to a level detrimental to plant
International guidelines developed in the 1960s use an electrical
conductivity value of almost 2,000 milligrams of salt per liter of water as the
threshold for salinity concerns. But for rice growers under California climate
and cropping conditions, researchers showed that yield losses started to occur
when levels got to about 1,300 milligrams of salt per liter of water. At
certain growth stages, damage resulted from even lower salinity levels.
Using guidelines developed with the researchers, regulatory agencies
approved procedures for allowing emergency releases of the water if salinity
levels increased to dangerous levels during the 1998 to 2000 growing seasons.
Thanks to sufficient rainfall, very few emergency releases were needed during
the past two years. The guidelines remain in effect for the upcoming growing
Scientific contact: Michael Shannon, ARS
George E. Brown, Jr., Salinity
Laboratory, Riverside, Calif., phone (909) 369-4814, fax (909) 369-4960,
news release on the renaming ceremony is available from Linda McElreath of
ARS Information Staff, phone (301)
504-1658, fax (301) 504-1641, firstname.lastname@example.org.