NAGP Makes Room for Swine Germplasm
The National Animal Germplasm Program (NAGP) has officially added swine
to its collection. Mandated by the U.S. Congress in 1990, the NAGP is
located at ARS' National Center
for Genetic Resources Preservation. Its first germplasm entry was 40
chicken lines cataloged in 2000. Consolidations in several meat-animal
industries have led to concerns about there being less genetic diversity
in swine.
By collecting swine germplasm, NAGP will help provide breeders the
genetic tools needed to develop animals with important traits, such
as disease resistance. Work is under way on a national swine breed survey.
NAGP researchers are looking for ways to improve use of super-cold
temperatures to preserve germplasm. Today's cryopreservation techniques
result in very low conception rates and small litter size compared to
industry norms. The scientists want to improve long-term germplasm storage
and better understand how it affects sperm and embryo viability. They
will also study proper storage of germplasm for beef and dairy cattle,
small ruminants, and aquacultured species.
Harvey D. Blackburn,
USDA-ARS National Animal Germplasm
Program, Fort Collins, Colorado; phone (970) 495-3268.
We're Getting New "Threads"!
Exceptionally soft bicomponent yarn is being spun with a new tandem
spinning system. This patented system works 10 times faster than the
conventional ring-spinning one. It's a combination of two different
technologies: air-jet spinning and friction spinning. It greatly speeds
up the process by which two types of fibersor two strands of the
same type of fiber, of the same or different qualitycan be coaxially
blended into a continuous yarn strand. By wrapping one fiber around
another, a core-wrap yarn is formed that exhibits qualities inherent
in both fibers. Often, the core material is a strong synthetic fiber
that imparts such useful mechanical and functional properties to fabric
as durability, dimensional stability, and wrinkle resistance. An outer
wrap of cotton adds desirable comfort characteristics.
Fabric made with this tandem-spun yarn doesn't pill, since the core
fiberoften a high-tenacity polyester that is prone to cause pillingis
almost completely encased in cotton, which doesn't pill. After heat-setting,
this "thermoplastic" core fiber usually provides satisfactory
shrink- and wrinkle-resistance to fabric, while the outer layer of cotton
provides the softness and absorbency of a natural fiber. The tandem
spinning technology is now available for licensing by textile processors.
Amar (Paul) Sawhney,
USDA-ARS Cotton
Textile Engineering Research Unit, New Orleans, Louisiana; phone
(504) 286-4568.
The Search for Salt Tolerance
A few years ago, eucalyptus trees seemed to offer promise as salt-tolerant
plants that could draw up and use salty irrigation-drainage water. Although
the trees survived, they used little of the saline water, so they didn't
thrive and grow much.
Now attention's turned to finding salt-tolerant forages that would
reduce the volume of salty drainage water while providing feed for grazing
sheep and cattle. Researchers used an elaborate sand-tank system to
test a variety of forage species. After ranking them by forage quality,
production potential, and mineral ion accumulation, the scientists found
that cultivars of alfalfa and tall wheatgrass performed best in the
experiment. After completion of field tests and ruminant nutritional
studies, it may be possible to recommend forages that will not only
feed grazing animals, but also help solve the problem of saline irrigation
water disposal.
Catherine M. Grieve,
USDA-ARS George E. Brown, Jr.,
Salinity Laboratory, Riverside, California; phone (909) 369-4836.
Pyramid Scheme for Better Broccoli
Concerns about pesticide use have led breeders to develop broccoli
varieties with natural resistance to downy mildew. Growers formerly
dependent on fungicide applications to prevent this costly scourge can
now simply grow varieties resistant to the fungal cause, Peronospora
parasitica. But fungi and other plant disease agentsas well
as insect pestsare notorious for developing an ability to overcome
resistance in plants, over time. So it's very good news that scientists
have found genetic markers that easily identify broccoli varieties with
natural resistance to downy mildew. These markers will aid development
of future varieties with more durable resistance.
The long-range goal is to gang, or "pyramid," several resistance
genes into new broccoli varieties, to build in multigene protection
that will be much harder for disease-causing microbes to overcome. Another
goal is to improve understanding of how plants inherit their resistance.
By studying how it works with one or more particular varieties, scientists
will be able to devise strategies for breeding resistance in new and
better broccolisas well as in related cole crops, such as cauliflower
and cabbage.
Mark W. Farnham, USDA-ARS
U.S. Vegetable
Laboratory, Charleston, South Carolina; phone (843) 556-0840.
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