College STation, Texas
June 15, 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." |