OVERVIEW OF THE BARLEY PROGRAM
The Virginia Tech’s barley-breeding program is the largest and one of only a
few surviving programs in the Eastern United States. Our program is
significantly diverse with breeding efforts on development of hulled and
hulless winter barley cultivars and a major focus on incorporation of value
added traits geared towards development of new markets.
Winter barley is an integral component of the cropping system in the Eastern
United States. However, production has declined dramatically due to low
world market prices and decreasing subsidies for producers even though the
region is a fed grain deficient area. It is a well known fact that yields of
soybeans following barley are significantly higher than those following wheat.
Production of two winter annual crops allow producers to extend the time
available for both harvesting of small grains and planting of soybeans, and
also provides an alternate crop to reduce the buildup of crop-specific
pathogens. Developing cultivars with defense against diseases will reduce the
need for fungicides and decrease input costs. The economic viability of U.S.
barley industry will be enhanced by helping farmers to reduce production
costs and increase profitability of barley cultivars that possess genes that
produce high yield, superior quality, which can be use in high-value markets
and will enhance the profit margin for farmers.
Prior to the early 1990’s winter barley cultivars released and grown in the
Eastern United States were traditional hulled feed barley types, which have
been grown for centuries in this region as feed for all classes of livestock.
Current demands for low-fiber, high-energy grains by the vertically
integrated swine and poultry industries and availability of brewer’s distilled
grains for beef and dairy industries have resulted in greatly reduced demand
for traditional feed barley in recent years. In the mid 1990’s, the Virginia
Tech Breeding Program realized that survival of winter barley as a viable
crop was dependent on development of commercially acceptable winter
hulless barley cultivars having high value traits for specific end uses. Hulless
barley is similar to hulled barley in all aspects, except the hulls thresh free of
the seed when combined. Since the hulls make up about 13% of the dry
weight, yields of hulless barley are expected to be lower than those of hulled
barley. However, during the past 10 years, the Virginia Tech barley breeding
program has developed hulless lines that yield 314-1129 kg/ha-1 (5-15
bushel/acre) higher than initial winter hulless lines available. Many lines have
improved straw strength, grain plumpness and better resistance to prevalent
diseases. In addition, increased interest in use of hulless barley, having high
energy and digestibility in manufacturing food and fuel products, has
accentuated efforts to develop winter hulless barley cultivars having greater
marketability in both domestic and foreign markets.
OVERALL OBJECTIVES
Our primary goal is to develop high yielding and high quality winter barley
cultivars designed for specific end uses and having desirable combinations of
high value traits, such as hulless seed, waxy endosperm, lower fiber, reduced
phytic acid content, higher protein, starch and energy, and high or low beta
glucan content depending on end use. Another objective of our program is to
develop winter barley cultivars with resistance to several important barley
diseases for the Eastern U. S. barley growing region and also to develop
improved breeding and selection methods that are more efficient and effective
(i. e. use of molecular markers as a selection tool).
BARLEY BREEDING AND TESTING PROTOCOLS
Our program makes more than 200 barley crosses each year and the
populations are advanced using a modified bulk breeding method, where we
select and bulk heads each generation during the inbreeding phase. Pure lines
are selected beginning in the F4 generation. Approximately and over 300 pure
lines are evaluated in yield tests at five locations in Virginia annually. Seedling
tests of advance barley lines are routinely conducted for reaction to three
races of leaf rust and one composite isolate of powdery mildew in the
greenhouse. In field tests, disease reaction data are also collected for all
prevalent diseases (leaf rust, net blotch, Barley Yellow Dwarf Virus (BYDV),
powdery mildew and Fusarium head blight). Other traits evaluated in field
trials include, winter hardiness, heading date, plant height, straw strength,
grain yield, test weight and moisture, thresh ability and hull adherence, seed
quality. Chemical analysis of grain composition of our current advance
barley lines are also conducted by the USDA-ARS, Eastern Regional Research
Center in Pennsylvania. Our latest breeding effort focuses on incorporation of
better resistance to net blotch into our material. We also are backing crossing
low phytic acid trait into some of our newer barley lines.
DEVELOPMENT OF HULLESS BARLEY VARIETIES
Efforts have been initiated by the Virginia Tech breeding program to accelerate
development of high yielding, higher quality and improved hulless barley cultivars
for use as animal feed, human consumption and domestic fuel ethanol production.
In this regard, we will continue to deploy a combination of top and backcross
breeding methods and evaluate barley lines derived from crosses made
between superior hulled cultivars or breeding lines with outstanding hulless
lines from the breeding program. In 2005- 2006 season, thirteen elite hulless
lines were evaluated in Virginia State Variety Trials. An additional 73
advance hulless lines were also evaluated in cooperating states (Maryland,
Kentucky, Delaware, North Carolina and South Carolina). To date, we have
developed over 4000 hulless barley populations. Twenty five advanced lines
were selected from 48 entries in a 2006 hulless preliminary test, and 77 lines
were selected from 230 entries in a 2006 hulless observation nursery. We also
have made great progress in developing and identifying new hulless lines for
potential release. Among 13 hulless entries in Virginia Tech State barley trail
conducted at seven locations in 2005-2006, advanced hulless line VA04H-53
ranked 1st in grain yield (90 Bu/ac). Additionally, VA03H-61 ranked 3rd (88
Bu/ac) similar to Doyce, but had the highest test weight (60.6 Lb/bu) and
VA01H-68 were among the top yielding lines with 85 Bu/ac and a test weight
of 58.4 Lbs/bu. VA01H-68 is also two or more days earlier heading than
Doyce. Release request for VA01H-68 will be submitted in December, 2006. In
addition, elite hulless lines VA03H-61 and VA04H-53 are being considered for
potential release. We also will continue to work with animal scientists, swine
and poultry nutritionists, and industry personnel to determine the potential
benefits of hulless barley as a feed component and what improvements are
needed to make winter barley more acceptable as a feed stock. Perdue Farms
continuing commitment to offer contracts to growers in the region to produce
and deliver grain of Doyce hulless barley in 2006 for a large scale feeding trail
also provides promise for initial market for hulless barley.
CONCLUSIONS AND FUTURE GOALS
• Develop superior winter barley cultivars that are adapted to the Eastern
U. S. barley growing region
• Develop winter hulled and hulless barley lines with improved grain
yield, test weight, straw strength, and disease resistance.
• Continue efforts are being made to improve yield and quality with
emphasis on high-value traits of hulless lines for specific markets.
• More chemical and nutritional analyses are being conducted to
ascertain the current and future potential of barley and particularly
hulless barley as a new commodity and its potential uses in new
markets, e.g. ethanol, food and feed.
• Develop new knowledge on the genetics of barley chemical composition
that may help establish new uses and market for hulless barley.
• Major emphasis on transforming barley into a crop that will have value
and new end uses.