College Station, Texas
July 8, 2004
A scientist with the
Texas Agricultural
Experiment Station said the development of corn with
improved protein quality would reduce the need for soybean
additives when feeding corn to swine and poultry.
Corn is deficient in two
essential amino acids, lysine and tryptophan. Increasing the
relative content of these two amino acids is the project of corn
researcher Dr. Javier Betran.
The resulting
nutritionally-improved corn, known as Quality Protein Maize,
could have positive implications not only for livestock feeding,
but also for human consumption – particularly in developing
countries in Latin America, Africa and Asia. There, corn is the
main food staple.
Nobel laureate Dr. Norman
Borlaug, a distinguished professor of international agriculture
at Texas A&M University, has said new technological advances are
key to helping developing countries meet future food supply
demands.
He has said his greatest worry
is Africa, because of its high rates of population, little
application of improved technology and escalating food deficits.
Borlaug and the International Center for Wheat and Maize
Improvement are promoting the development and adoption of
Quality Protein Maize in developing countries around the world.
While better protein corn would
help human nutrition, it would vastly improve feeding costs in
segments of animal agriculture by reducing the need of better
protein supplements, Betran said.
"Corn is mainly used for animal
feeding in the United States," Betran said. "About 65 percent
goes into animal feed. If you feed poultry the same corn, you
need to supplement it with another product. Soybeans or
synthetic lysine are commonly used to provide the protein
quality that the corn doesn't have. Our approach is to improve
corn to enhance the content for these two essential amino
acids."
In the early 1960s, scientists
discovered a "mutant" maize that contained protein with nearly
twice as much lysine and tryptophan as found in normal maize.
Called "Opaque-2 maize," the protein had a 90 percent of the
nutritive value of the proteins in skim milk - the standard
against which cereal protein is normally measured.
But it was later discovered by
incorporating the "Opaque-2" mutation to corn, it yielded less
grain. It also had a higher moisture content and was more
susceptible to fungal and insect infestations.
"Those facts right there are
not well received by farmers," Betran said. "Our challenge is to
put together the protein quality with a competitive yield grain.
We want it to be a value-added trait that perhaps has good
appealing characteristics. Farmers are not ready at this time
for something that has the protein quality but is not a
high-yielding variety."
The research includes another
component -- making a variety that is less susceptible to
aflatoxin, which has been a nemesis for Texas farmers the past
decade. Aflatoxin, a mold that commonly develops during periods
of drought, can cause illness or death in livestock that consume
it.
"We want to have something that
is high quality, but yet have low-risk to aflatoxin and it is
adapted to our growing conditions," Betran said. "We are
selecting and breeding materials from different origins to
develop a value-added corn with a desirable combination of
traits." |