Agriculture Reference
In-Depth Information
Asian foods. Antioxidants have recently been
found to exist in some wheat cultivars at levels
comparable to berries, fruits, and other foods.
Improving the consistency of high antioxidant
levels could offer another avenue for extending
wheat-based foods to the nutraceutical market.
The environmental effect on antioxidant activity
is a key component overlaying the genetic poten-
tial. Understanding the environmental triggers
could lead to a breakthrough in this area.
The potential to produce a high-yielding wheat
cultivar for animal feeding, fermentation feed-
stock, and for other industrial uses was given a
low priority in 2004, but this research area is
receiving greater consideration as commodity
grain prices are driven higher by ethanol produc-
tion. For industrial uses, the approach now is to
maximize agronomic yield, suppress protein
content, convert the starch to a waxy type, and
reduce phytate content. This wheat would
need to be contract-grown or otherwise managed
to assure its segregation from food-wheat
cultivars.
Utilization of by-products from the wheat fi eld
include conversion of wheat straw to composite
board products, hydrolysis and chemical conver-
sion to xylitol for the sweetner market, and
hydrolysis followed by fermentation to ethanol or
other valuable chemicals. Priorities have rapidly
changed since 2004, as the fi rst cellulosic ethanol
plant in Kansas is targeting wheat straw as its
primary cellulosic feedstock source.
wheat came to dominate the region, which might
very well be a historical accident, or in genetic
terms, a “founder effect.” Had the fi rst widely
adapted winter wheat cultivars in the region been
white, the Great Plains might have developed into
a region of white wheat cultivation.
During the past 25 years, however, it has
become abundantly clear that many international
markets favor white wheat. To diversify the
product line of Great Plains wheat producers,
hard winter and spring wheat breeders initiated
programs to develop hard white wheat cultivars.
This development began in earnest in the late
1960s when Kansas State University (KSU)
wheat breeder, Dr. Elmer Heyne, was on sabbati-
cal leave in Australia, where the crop was entirely
white wheat. He recognized the potential of hard
white wheat and realized that it may be even more
adaptable to the growing conditions in the central
Great Plains. Hard white wheat breeding slowly
increased, mainly in Kansas, until 1990 when
hard white (HW) was established as a new class
of wheat by the USDA Federal Grain Inspection
Service (later renamed the Grain Inspection,
Packers and Stockyards Administration). This
enhanced the efforts directed toward HW devel-
opment in the KSU wheat breeding program and
other breeding programs throughout the Great
Plains.
Lower grain yields and greater occurrence of
preharvest sprouting relative to HRW in early
HW cultivars, including 'Arlin', 'Rio Blanco',
and 'Oro Blanco', limited acceptance of HW
wheat. 'Clark's Cream' (PI476305), a farmer-
selected cultivar with excellent preharvest sprout-
ing resistance, was released in 1972 (Anonymous
1972). Breeders at the Kansas Agricultural
Experiment Station (KAES) transferred this
sprouting resistance to improved experimental
lines, which were released to other breeders in
1988. In 1998, the KAES released its fi rst HW
cultivars, Betty and Heyne, to foundation seed
producers. These cultivars exhibited yield levels
comparable to HRW cultivars in their areas of
adaptation.
Following Kansas' lead (Morris and Paulsen
1992), nearly every remaining wheat breeding
WHITE WHEAT
White wheat breeding
Winter wheat production in the Great Plains has
been dominated by cultivation of hard red winter
(HRW) types. The fi rst successfully cultivated
landraces, 'Turkey', 'Kharkof', and 'Crimea',
were introduced from the Black Sea region of
southwest Asia in the 1870s; all were red wheats
(Cox et al., 1986). These lines, and various selec-
tions from them, formed the basis of all subse-
quent breeding efforts in the Great Plains. Red