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Scientists Gear Up to Counter Soybean Rust
Disease By Jan
June 27, 2002
A showdown is simmering. In one corner are Agricultural Research
Service (ARS) scientists and
collaborating researchers. In the other is a fungal rust disease whose 2001
arrival in South America has cast a menacing shadow over U.S. soybeans.
At stake is a nearly 2.9-billion-acre legume crop whose protein,
oil and derivatives are used in everything from baby formula and salad dressing
to biodiesel and printing ink. The rust fungus hasnt appeared on the U.S.
mainland yet, but ARS researchers Reid Frederick, Morris Bonde and Glen Hartman
arent wasting any time. Frederick and Bonde, for example, have already
developed a molecular method to rapidly detect the rust fungus based on
specific DNA sequences that are unique to it.
Since 2000, all three ARS researchers have worked with
scientists abroad to learn as much as they can about their fungal foes
basic biology, genetic variability, life cycle and pathogenicity. The so-called
Asian rust strain--the more aggressive of two known forms- -has spread to
Africa and South America, notes Hartman, at ARS
Germplasm, Pathology and Genetics Research Laboratory at Urbana, Ill.
Hartman, Frederick and Bonde also will spearhead a project
supported by the United Soybean Board to coordinate field tests at rust
hot-spot regions in China, Thailand, Zimbabwe, South Africa, Brazil
and Paraguay. There, theyll search for the best sources of soybean
resistance to the rust fungus. Inside a biocontainment facility operated by
ARS Foreign Disease-Weed
Science Research Unit at Fort Detrick, Md., theyll also expose
domestic and exotic soybean lines to multiple races of the fungus to determine
which offer the broadest range of disease resistance. And in fungicide trials,
theyll examine the chemicals effectiveness and potential
phytotoxicity to soybean plants.
Meanwhile, Iowa State
University collaborator X.B. Yang is using computer modeling to simulate
rust disease outbreaks on U.S. soybean-growing regions based on climate, wind
patterns and other criteria. By one simulation, the fungus establishment
causes soy crop losses of up to 40 percent.
ARS is the U.S. Department of
Agricultures principal scientific research agency.