West Lafayette, Indiana
May 7, 1999
Purdue University researchers have developed the first
commercial soybean variety with immunity to soybean cyst nematode.
"This new germplasm was the only one of 200 progeny from the cross between Williams
and Hartwig that had immunity to soybean cyst nematode," said John Ferris, Purdue
nematologist.
Soybean cyst nematodes are unsegmented parasitic worms found in 74 of Indiana's 92
counties. They are responsible for yield losses of up to 50 percent in some soybean
fields.
Ferris' research started as a way to produce new genetic "parents" (germplasm)
for commercial soybean seed breeders. "It wasn't our purpose to create a variety for
the retail market," he said. But farmers attending Purdue field days spotted the
variety and began to ask if they could buy the seed. The soybeans will be available in a
few years, when the seed stock is built up, according to Ferris.The new germplasm, PUSCN-14, is from a cross of Hartwig and Williams
genetic lines. The immune line was back-crossed with Williams to improve its agronomic
characteristics. Researchers chose Hartwig for its soybean cyst nematode immunity and
Williams for yield and
agronomic characteristics. Williams is found in approximately 82 percent of commercial
soybean
varieties.
Other than Hartwig, only two other sources of resistance, PI 88788 and Peking, have been
used extensively in cyst nematode breeding programs. Varieties with PI 88788 offer 85
percent resistance to the nematode, according to Ferris. The new variety is immune rather
than just resistant.
Because of expense and toxicity, farmers generally don't use chemicals to control soybean
cyst nematode. Therefore, once the nematodes show up in soybean fields, farmers must use
management practices, such as planting resistant varieties, to maintain good yields.
Soybean cyst nematodes are hard to spot because they are the size of a grain of sugar, and
visible symptoms on the plant mimic other problems such as mineral deficiencies, diseases,
soil compaction, drought stress and herbicide injury, Ferris said.
If farmers are unsure whether they have soybean cyst nematodes in their fields, they can
send pint samples of soil and roots from both infected and uninfected areas in separate
containers. Each sample should be labeled on the outside of the bag, and mailed to the
Nematology Lab, Department of Entomology, West Lafayette, IN 47907-1158. The Indiana
Soybean Board uses checkoff funds to pay the testing fee of $10 per sample.
Source: John Ferris, (765) 494-4610; john_ferris@entm.purdue.edu
Writer: Tim Hoskins, (765) 494-8402; news_students@aes.purdue.edu
Purdue News Service: (765) 494-2096; e-mail, purduenews@uns.purdue.edu
Company news release
N2023 |
