Prize-Winning Yields More Routine
By Don Comis
June 22, 2001
When youre a scientist trying to
help farmers get the highest possible yields, who better to turn to than
national yield contest winners?
It was on just such a farmers field that
Agricultural Research Service agronomist
Richard L. Cooper discovered his first yield barrier: soybean plants getting so
tall they fell over and yielded poorly. That was the prelude to his almost
quarter-century-long maximum yield experiment with soybeans.
Cooper, in Wooster, Ohio, removes every possible factor that limits
yields--like lack of water or fertilizer--to find the true potential of modern
varieties. That, and the long-term nature of his experiment, enabled him to
recently discover another previously unknown barrier: a delay in soybean
flowering caused by typically cool spring weather. Cooper is based at the ARS
Corn and Soybean Research Unit.
He found that warm spring weather triggers earlier flowering--and higher
yields. Until breeders develop earlier flowering varieties based on his
findings, Cooper recommends farmers plant soybeans up to two weeks earlier than
Cooper has developed a high-yield system for soybeans--70 to 100 bushels per
acre--that combines early planting with ARS-developed semidwarf soybean
varieties planted densely in narrow rows. Corn used in rotation with soybeans
in his research has produced 200-plus bushels an acre.
Cooper has found an unusual source of free irrigation water for
his system: excess rainwater from underground plastic drainage pipes, collected
in the wet spring. Norman R. Fausey, an ARS soil scientist at
Ohio State University in
Columbus, recommended the irrigation system and is working with Cooper to
integrate it into the maximum yield system--a first.
He and Cooper have built wetlands and reservoirs to store the drainage
water, which would normally empty into streams and possibly pollute them with
farm chemicals. Preliminary data indicate that the drained water becomes
significantly cleaner after being filtered through wetlands or reservoirs.
Then, during the dry, hot days of summer, farmers can irrigate through the
A more detailed story appears in the June issue of Agricultural Research, ARS
ARS is the U.S. Department of
Agricultures chief scientific research agency.