Amarillo, Texas
March 26, 2004
Small
wonders are in small grains.
Consider
those flour tortillas you munched on at dinner last night or the
toast you buttered this morning. These and many more products
and ingredients come from wheat, a small grain grown worldwide.
But,
wheat must have certain qualities to keep tortillas fresh
and pliable, and bread dough light and airy. Characteristics
bred within wheat helps bread stay affordable on the grocer's
shelf. Work by plant breeders also helps farmers grow wheat
abundantly, cheaply and in environmentally-responsible ways.
Consumers need rarely to think about the process. That's the
best outcome, say researchers working in laboratories and
breeding facilities run by universities, experiment stations, or
commercial companies around the globe.
In Texas
much of this work is conducted by the Texas Agricultural
Experiment Station, and its education outreach partner, Texas
Cooperative Extension, both agencies are part of the
Texas A&M University System
Agriculture Program.
With a
statewide team working in concert, the Small Grains Improvement
Program includes plant breeders and scientists in cereal
chemistry, plant pathology, entomology and agronomy, and
Extension specialists at three centers of excellence--Amarillo,
Vernon and College Station. The A&M wheat breeding program is
built upon more than 50 years' work by pioneers such as the late
Dr. Kenneth Porter, whose laboratory and greenhouses near
Bushland became known worldwide.
Some 25
varieties have been released through the A&M program to date.
Many are widely grown across the Great Plains. The benefits
include monetary and environmental savings because producers can
grow higher yielding, drought and insect tolerant wheats that
keep costs down with fewer inputs to control pests.
Most
varieties also have built-in qualities to make foods taste
better and stay fresh longer, said A&M's Jackie Rudd, wheat
breeder at the Amarillo and Vernon Centers.
"Two
more recent releases, TAM 110 resists greenbug damage and TAM
111 combines improved yield with superior baking quality," he
said. Other well known varieties include Sturdy, Tascosa,
Caprock, Lockett, Siouxland 89 and TAMEX (a joint release by
Texas A&M University and New Mexico State University).
Experimental seed from A&M breeding efforts is certified after
years of testing, followed by release by the Texas Foundation
Seed Service to contract growers who help increase the seed for
later distribution by commercial companies.
Every
year, breeders are evaluating thousands of seedlings before
launching experiments with a single strain. A decade or more of
research must take place before a farmer plants a single seed
from a given variety.
Dr. John
Sweeten, Experiment Station research director at Amarillo said,
"Our first goal is assisting Texas producers in meeting the
challenges presented by consumers clamoring for wheat-based
products."
"It's
easy to say we need to improve quality for certain end uses. The
hard part is defining which protein and starch characteristics
are needed for a particular kind of bread product for example,"
Rudd said.
Building
a better tortilla is what tempers the work led by Dr. Ralph
Waniska, A&M cereal chemist at College Station.
"Each
new technology we discover helps extend tortilla freshness
during storage, or maintain other quality criteria such as size,
opacity or dough properties," said Waniska, who has at least
three new patents on tortilla formulations in the works and is
promoting his latest developments to millers and bakers.
Proteins
in flour tortillas act differently from those in bread, Waniska
said. Tortillas must stay flexible over weeks of storage. Bread
firms or stales after only five days. Proteins for freshness are
prized. To get the desired results for baked tortillas, Waniska
wants the proportion of proteins such as glutenins and gliadins
in wheat to vary.
Glutenins and gliadins help create the sticky and rubbery gluten
needed for dough. This substance affects baking quality and has
a unique amino acid composition and structure. In addition,
bread dough needs a consistent, strong, resilient gluten to hold
in air bubbles during fermentation and baking.
"The
gluten network needs to be spreadable but not elastic, and
mellow to extend into a large-diameter tortilla, and there's
room for improvement," Waniska said.
Dr. Dirk
Hays, an A&M molecular geneticist at College Station also looks
at proteins, enzymes and other compounds that may provide
competitive advantages for niche products. These scientists are
focused on helping the producer, processor and consumer capture
more value through specific qualities developed within a wheat
variety.
Texas
farmers plant small grains such as wheat, oats, rye, triticale
and barley, with wheat accounting for nearly 90 percent of the
acreage. Each year, farmers plant some eight million acres from
the Gulf Coast to the Panhandle. From industry statistics in the
1990s, the farmgate production value for all five crops averaged
near $420 million per year, Rudd said.
How
important is a single new variety? Consider that wheat yields
have increased by 30 percent in the past 30 years -- a trend
that is continuing. Rudd believes at least half the increase
must be attributed to the adoption of new varieties. New
varieties generally yield 3 to 4 percent higher than older ones.
With an annual production of 100 million bushels in Texas alone,
when calculated at $3.50 per bushel, for example, a 3-percent
increase could return more than $10 million to the state's
economy.
And
that's just grain production. Wheat is also used as winter
pasture for grazing animals—beef and dairy cattle, sheep, goats
and assorted wildlife. About 65 percent of the small grain
acreage is grazed annually, with a value (in pounds of animal
production) greater than $400 million, according to Agricultural
Statistics Service figures. Oats, rye and triticale are prized
more for their value as feed than food. Up to 80 percent of oats
are grazed each year, Rudd explained.
In the
Texas Panhandle at the Bushland Station--millions of wheat seeds
are stored in thousands of paper envelopes, or a living archive
of genetic diversity that feeds the A&M breeding program. Recent
upgrades to facilities include a new seed storage unit, named to
honor breeding pioneer Porter. Nearby are three state-of-the-art
greenhouses built with funding almost entirely from the wheat
industry.
Breeders
look at wheat varieties and other grasses to first find desired
traits before starting plant crosses in greenhouses. The next
step involves the field nurseries. Typically, researchers
initially plant 20 to 30 kernels in a 2-foot-long seedbed called
a head row. They may plant up to100,000 head rows causing a
field to resemble a checker board . Field plots are the
researcher's first opportunity to see true breeding lines
emerge.
The
head-row plantings may be repeated over a number of growing
seasons with breeders winnowing their selections toward the
desired traits each time. Eventually, only 100 specimens may be
chosen for extensive field trials. Fewer than 50 types actually
make it to statewide evaluation. Multi-state trials will follow
in the wheat zones of Colorado, Kansas, Nebraska, New Mexico,
Oklahoma and Texas.
Other
testing takes place at the Texas A&M Cereal Quality Laboratory,
established in 1965 and headed by Dr. Lloyd Rooney. Here,
scientists evaluate bread baking and milling properties such as
those required in flour tortillas and breads.
On the
crop production side, Hays and Dr. William Payne, a crop stress
physiologist at Bushland, are seeking the true physiological
tolerances of high temperature and drought.
"When
spring temperatures jump too high during pollination, both grain
development and quality are affected," said Hays. "Such trauma
causes the plant to suffer. First it may dry prematurely,
causing grain shriveling and weight loss. Flour yield and
quality also fall with severe damage, and dough strength
collapses."
Focusing
on the molecular mechanisms regulating a plant's adverse
responses, Hays is evaluating Middle Eastern and Australian
cultivars, which have many of these coveted traits. If
successful, this work will result in more high-yielding
varieties that better tolerate heat and drought.
Many
foods such as noodles, frozen dough products or breads possess
parts from many wheats. Manufacturers take these additives and
blend them together to achieve their products' most favored
qualities. Why not build what's needed into the plant?
Rudd
points to marketplace trends moving some aspects of the breeding
program toward specialized product lines. In the future, wheat
may be seen more as an ingredient than as a conventional
commodity.
"Recent
efforts to establish two centers of breeding excellence at
Amarillo and College Station are seen by the industry as
extremely positive," said Rodney Mosier, who heads the Texas
Wheat Producers Association. He and others from the small grains
industry have teamed with Texas A&M faculty to form the Texas
Small Grains Advisory Committee, a group providing guidance and
resources to accomplish research goals.
The
Experiment Station plans to step up oat breeding in the future.
At least two new oat varieties are due out soon. The wheat
breeding efforts primarily target hard-red winter varieties that
do well in the Texas Panhandle and Rolling Plains, and typically
are used in breads. Station scientists also are looking at some
soft-red winter lines that are more often used for milling and
baking.
Two
triticale varieties, on which work began in the mid-1980s, are
nearing release, and the first Texas A&M issues certified for
use as winter forage.
Farther
back in the research pipeline are other varieties that offer
additional promise, so the plant breeding work will continue
well into the future. |