Group Title: Agricultural research (Washington, D.C.)
Title: Agricultural research
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Title: Agricultural research
Uniform Title: Agricultural research (Washington, D.C.)
Physical Description: v. : ill. ; 25-28 cm.
Language: English
Creator: United States -- Science and Education Administration
United States -- Agricultural Research Administration
United States -- Agricultural Research Service
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Place of Publication: Washington D.C
Publication Date: September 2000
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Subject: Agriculture -- Periodicals   ( lcsh )
Agriculture -- Research -- Periodicals   ( lcsh )
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Statement of Responsibility: U.S. Department of Agriculture.
Dates or Sequential Designation: Began with vol. 1, no. 1 (Jan. 1953).
Issuing Body: Vols. for Jan./Feb.-Nov. 1953 issued by: Agricultural Research Administration; Dec. 1953-<Sept. 1976> by: Agricultural Research Service; <June 1979>-June 1981 by: the Science and Education Administration; July 1981- by: the Agricultural Research Service.
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Volume ID: VID00036
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Full Text





Ar a R h S




















































14


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FORUM


Horticultural

Research: It's a

Growing Process

Walk down the produce aisle in almost
any grocery store in the country and
you'll find a diversity and an abundance
of fruits, vegetables, nuts, and even
flowers that rivals the fabled magic
cornucopia. Stores stock this bounty
because consumers want and buy more
produce each year.
Consumer demand for horticultural
crops has made them one of the fastest
growing segments of U.S. agriculture.
This crop group, which includes nursery
and floral crops and turfgrass, is now the
country's third most important commod-
ity group. Grower receipts for horticul-
tural products have been increasing at a
rate of $500 million annually.
What is fueling this demand?
For one thing, Americans are more
health conscious. Our knowledge of the
importance and role of fruits and vege-
tables in maintaining health is becom-
ing much more specific. Discoveries like
ARS' work with high-antioxidant fruits
and vegetables-found to prevent and
even restore some loss of nerve function
in aging rats-are helping focus atten-
tion on the specifics of optimum diet.
The economic boom of the 1990s
brought a higher standard of living for
many people. With more disposable in-
come, people are spending more money
at the grocery store on a wider variety of
fresh produce. Sales of floral and nurs-
ery crops have similarly increased.
In addition, the ethnic diversity of the
U.S. population is expanding at a prodi-
gious rate. This increase in diversity,
along with the growth of global trade,
has introduced Americans to a plethora
of exotic produce and ornamentals.
With exposure, U.S. consumers have
become more adventurous in trying un-
usual horticultural products. Fifty years


ago, fresh pineapples were rare in main-
stream supermarkets; 25 years ago, man-
gos and papayas were uncommon; today,
these fruits are regular offerings, along
with starfruit,jicama, and plaintains. And
orchids are commonplace at garden
centers.
So where does horticulture go from
here? Research is moving in a number
of important new directions, besides
pursuing traditional avenues such as in-
creasing pest and disease resistance and
improving growing techniques.
As consumer demand pushes exotic
produce from a niche market to everyday
fare, scientists are working on ways to
grow many of these crops domestically.
Researchers are also developing ways to
extend the shelf life of horticultural
produce.
U.S. consumers have become accus-
tomed to having access to fresh fruits and
vegetables all year. The ability to store
produce longer means a U.S. crop can
be used over a longer period or an im-
ported shipment can come from farther
away-including from areas where the
harvest season differs from that in the
United States.
Enhanced nutrition is also receiving
new emphasis. ARS researchers are
breeding for specific nutritional traits,
such as enhanced carotenoid content,
mineral composition, and other health-
promoting compounds. This issue of
Agricultural Research features work in
Poplarville, Mississippi, where scientists
are developing berries with higher lev-
els of resveratrol, a compound that has
anticancer properties and cardiovascular
benefits (p. 10).
Food safety issues, especially pesti-
cide residues and bacterial contamina-
tion, are another priority for horticultural
research. Consumers are not only
demanding greater variety in flavor,
color, and access, they also want to know
that the food they buy, including
horticultural crops, is completely safe.
ARS researchers are developing baseline


information needed to develop plans for
Hazard Analysis Critical Control Points
(HACCP) for many crops and processing
plants.
Safety of products from the genetic
engineering of horticultural crops is also
of greater concern. ARS is doing more
risk assessment to help ensure that gene-
altered crops are safe for people and the
environment. The agency is committed
to rigorous safety testing before a variety
or technology is released to the public.
Biotechnology is critical to research
and its ability to meet consumer and
industry demands. With new genetic
technologies, the time required to de-
velop a new variety can potentially be
cut in half. Scientists can pinpoint the
genes that control desired traits, and
these genes can be efficiently transferred
into new varieties using direct gene
transfer technology or conventional
breeding methodology.
But ARS researchers are not simply
concerned with inserting new genes.
They wish to manipulate how and when
the new genes function. From control of
plum pox virus and other disease-
causing pathogens to extended shelf life,
ARS scientists are using genetic engi-
neering to improve horticultural crops in
many ways. The story on page 14 focuses
on the research of ARS plant physiol-
ogist Autar K. Mattoo, in Beltsville,
Maryland. He is working to improve the
shelf life and quality of tomatoes.
As research makes horticultural crops
more nutritious, safer, tastier, more con-
venient to ship, and easier to store,
consumer interest and demand will
continue to grow. As consumer demand
increases, research will be called on to
provide even more improvements. It's a
growing process.

John R. Stommel
Acting National Program Leader
Horticulture and Sugar Crops
Beltsville, Maryland


Agricultural Research/September 2000










September 2000
Vol. 48, No. 9
ISSN 0002-161X

Agricultural Research is published monthly by the
Agricultural Research Service, U.S. Department
of Agriculture (USDA). The Secretary of
Agriculture has determined that this periodical is
necessary in the transaction of public business
required by law.
Dan Glickman, Secretary
U.S. Department of Agriculture
I. Miley Gonzalez, Under Secretary
Research, Education, and Economics
Floyd P. Horn, Administrator
Agricultural Research Service
Sandy Miller Hays, Director
Information Staff


Editor: Robert Sowers
Associate Editor: Sue Kendall
Art Director: William Johnson
Photo Editor: Anita Daniels
Staff Photographers: Scott Bauer
Peggy Greb


(301) 504-1651
(301) 504-1623
(301) 504-1659
(301) 504-1609
(301) 504-1607
(301) 504-1620


Information in this magazine is public property and
may be reprinted without permission. Non-
copyrighted photos are available to mass media in
color transparencies. Order by photo number and
date of magazine issue.
Agricultural Research magazine articles and
photographs are posted on the World Wide Web
monthly at http://www.ars.usda.gov/is/AR/.
Subscription requests should be placed with New
Orders, Superintendent of Documents, P.O. Box
371954, Pittsburgh, PA 15250-7954. See back
cover for ordering information. Complimentary 1-
year subscriptions are available to public libraries,
schools, USDA employees, and the news media.
Send requests or comments to: Editor, Agricultural
Research, 5601 Sunnyside Ave., Beltsville, MD
20705-5130, e-mail armag@asrr.arsusda.gov.
This magazine may report research involving pesti-
cides. It does not contain recommendations for
their use, nor does it imply that uses discussed
herein have been registered. All uses of pesticides
must be registered by appropriate state and/or fed-
eral agencies before they can be recommended.
Reference to any commercial product or service is
made with the understanding that no discrimination
is intended and no endorsement by USDA is
implied.
The U.S. Department of Agriculture (USDA)
prohibits di, nmjnalon in all it programs and
activities on the basis of race, color, national
origin, sex, religion, age, disability, political
beliefs, sexual orientation, or marital or family
status. (Not all prohibited bases apply to all
programs.) Persons with disabilities who require
alternative means for communication of program
information (Braille, large print, audiotape, etc.)
should contact USDA's TARGET Center at (202)
720-2600 (voice and TDD).
To file a complaint of discrimination, write
USDA, Office of Civil Rights, Room 326-W,
Whitten Building, 1400 Independence Avenue,
SW, Washington, DC 20250-9410, or call (202)
720-5964 (voice and TDD). USDA is an equal
opportunity provider and employer.


Agricultural Research



Curbing Pests in Hawaii's Ornamental

Paradise 4


Potatoes' Resistance to Late Blight May Be

in Their Mexican Genes 8


Blissful Blueberries 10


Pomological Watercolors: A Wealth of
Beauty and Detail 12


Transgenics for a Better Tomato 14

Rotate To Prevent Replant? 16


Locate Outstanding Woody Ornamentals-
Online 18


Bringing You Better Beans 20

Science Update 23


Cover: Tropical flowers like these gardenias and anthuriums bring premium prices at
nurseries and floral shops around the world. But these beauties are being attacked by
insects. ARS scientists are looking for environmentally friendly ways to protect the
showy plants. Photo by Scott Bauer. (K9052-1)



In the next issue!

0' MITES ARE EVERYWHERE-on plants, on animals, in our homes, even in our
food and bedding. Now scientists can study them exactly as they are. Using a fast
freezing process called cryofixation, researchers can freeze mites in their tracks to
study them intact and undistorted on their hosts. Then, with the use of high-
magnification scanning electron microscopy, they can take a close look to find better
management and control methods.

( WILL PRECISION AGRICULTURE BE PROFITABLE? A systems approach
designed to study all possible variables in a field could provide answers in the future.

(' FIGHTING E. COLI-New rapid testing methods make it easier to monitor how
well prevention strategies work. DNA fingerprinting and making the bacteria glow are
two detection techniques under study.


Agricultural Research/September 2000




SCOTT BAUER (K9013-1)





Agl




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Agricultural Research/September 2000









Curbing Pests in Hawaii's Ornamental Paradise


SCOTT BAUER (K9054-1)


-, mall, stealthy snails
can cause even the
'most regal of Ha-
.. waii's greenhouse-
grown orchids to flop
sadly in their pots. The tiny mollusks,
called orchid or bush snails, feast on sur-
face or lateral roots that would otherwise
keep the exotic blooms upright.
Known to scientists as Zonitoides
arboreus, the molluscan marauders are
hard to detect and even harder to kill with
commercial chemicals, according to
Agricultural Research Service biologist
Robert G. Hollingsworth.
A new member of the scientific team
at the U.S. Pacific Basin Agricultural
Research Center in Hilo, Hawaii,
Hollingsworth is hunting for ways to
combat the snails. The little pests have a
bluish-grey body and a yellow-brown,
translucent shell. A full-grown adult is
smaller than a fingernail.
Hollingsworth is also targeting two
other floral crop foes. They are insects
called thrips and coffee green scales. His
experiments should lead to new, effec-
tive, and more environmentally friendly
ways to protect not only orchids, but also
other splendid tropical flowers like
gardenia, anthurium, ginger, bird-of-
paradise, and heliconia, plus an array of
exotic tropical palms. These and other
long-lasting cut flowers and hardy potted
plants from Hawaii command premium
prices at nurseries and floral shops
worldwide.

Nail That Snail!
For the most part, small businesses,
often family run, make up Hawaii's $70
million ornamental crops industry. In a
survey that Hollingsworth and colleague
Kelvin T. Sewake of the University of
Hawaii conducted among orchid grow-
ers, about half of those queried com-
plained that the orchid snail costs them,
on average, about $5,000 a year in con-
trol expenses and lost sales.
The snail's protective coloration and
small size make it hard to find in soil

Agricultural Research/September 2000


substitutes-bark, peat moss, cinder, or
pieces of coconut husk, called coir-
used to fill greenhouse pots. Too, the
snails live and work independently. That
makes them harder to spot than if they
stayed in groups.
"We aren't finding them in heavy con-
centrations," reports Hollingsworth, "but
even if only two or three of these snails
are feeding on an orchid in a 4-inch pot,
they're pretty much going to eat up all
of the surface roots in only a couple of
months."
These factors can make it hard for
growers to know that they have a snail
problem until the besieged blooms top-
ple over. "By that time, if growers do use
a chemical," says Hollingsworth, "some-
times it won't work. And even if it does,
the results often aren't obvious because
the snails-dead or alive-are so hard
to find."
Right now, Hollingsworth is trying to
learn more about the snail's little-known
biology. And, he's working to build a
large colony of wild snails for use in
greenhouse and petri dish tests of
molluscicides.
"These chemicals are our best options
right now," he says, "but most were de-
veloped for other pests-like garden
slugs-not for this snail."

Thwarting Thrips
Orchids and other lush tropical plants
need protection from other pests, as well
as from snails. Small, winged insects
known as thrips, for example, like to feed
on leaves, stems, and flowers. Nearly
invisible to the naked eye, pests such as
palm thrips (Thrips palmi), which attack
orchids, or banana rust thrips (Chae-
tagnaphothrips signipennis), which
trouble anthuriums, can wreak havoc in
greenhouses.
Hollingsworth, along with Kelvin
Sewake and Arnold H. Hara of the
University of Hawaii, have developed
new guidelines for scouting, or detecting,
thrips in shadehouse or greenhouse
orchids.


Orchid color plays a role in attracting
thrips. Here, Robert Hollingsworth (left)
and Dendrobium orchid grower Clarence
Ono discuss which colors are most likely to
attract the pest.













SCOTT BAUER (K9015-1)


SCOTT BAUER (K9010-1)
Yellowish coffee green scales produce a
sweet, sticky liquid called honeydew. The
substance is a food source for this black
sooty mold fungus on these gardenia leaves.


About 26 percent of the orchid grow-
ers that Hollingsworth and co-research-
ers surveyed in Hawaii said they scout
their orchids for thrips. Their decision of
whether or not to spray plants may be
based on how many thrips they find.
These growers apply pesticides about 25
times a year.
In contrast, some growers spray ac-
cording to the calendar, applying pesti-
cides regardless of whether or not they've
actually spotted any thrips. They spray
about 38 times a year.
Until now, says Hollingsworth, grow-
ers who opted to scout "didn't have data
indicating how many samples were really
necessary." To fill that gap, Hollings-
worth, Sewake, and Hara investigated
thrips populations on orchids, then
developed a new, practical, and statis-
tically sound sampling strategy. Says
Hollingsworth, "Growers can use it to
determine how many orchids they need
to sample to have a reasonably good
chance of detecting thrips. Once they've
followed the sampling protocol, they can
decide whether to apply insecticide."

No Break for the Coffee Green
Scale
A six-legged, soft-bodied insect called
coffee green scale can plague gardenia,


ginger, and a host of other crops-
including citrus and, of course, coffee.
The insect, known as Coccus viridis,
stunts growth and causes leaves to yellow.
The adults are oval and greenish
yellow. Various species of ants befriend
them, chasing away predators and
parasites that might otherwise make a
quick snack of the scales. In return, ants
get to nosh on honeydew that the scales
produce.
To avoid infestations, shipments of
fragrant, creamy-white gardenias from
Hawaii to the U.S. mainland have been
banned since 1948. "Gardenias," says
Hollingsworth, "can't be used in flower
leis or taken home by tourists-much to
the disappointment of many of our
visitors."
Now, data gathered by Hollingsworth
and Hara might help change all that. They
tested hundreds of gardenia blossoms and
leaves in experiments with more than a
half dozen pesticide dips. They recom-
mended to USDA's Animal and Plant
Health Inspection Service that the best-
performing of these dips-combined
with inspections of growers' fields every
6 months and of the flowers just before
shipment-should ensure that the gar-
denias are free of coffee green scale.
APHIS specialists are now reviewing the


Biologist Robert Hollingsworth examines
Dendrobium orchid flowers to determine
how thrips are typically distributed in this
crop.


Agricultural Research/September 2000












SCOTT BAUER (K9019-1)


Despite their small size, these 1/4-inch-wide snails (called
Zonitoides arboreus) are capable of destroying the thick corky
roots of the orchid plant.


SCOTT BAUER (K9016-1)
recommendations.
In the meantime, Hollingsworth plans
to use coffee green scales infesting gar-
denia leaves as a research model. That
means they'll be an essential part of new
tests of promising compounds that might
zap a variety of other floral pests.
One target: long-tailed mealybug
(Pseudococcus longispinus). It attacks
plants like ginger, heliconia, or palms.
The insect gets its name from the tail-
like filaments that trail behind the oval
bodies of the adults. B T 4
"Mealybugs have a protective waxy
coating on their bodies that makes them lS
fairly impervious to insecticides,"
Hollingsworth notes. "We'd like to help
growers develop an improved spray or
dip that would keep their cut flowers and
potted plants free of mealybug hitch-
hikers."-By Marcia Wood, ARS. Shipments of gardenias to the U.S. main-
land have been banned since 1948 because
This research is part of Crop Protec- of fears that they carry coffee green scale
tion and Quarantine, an ARS National insects. But Hollingsworth's research with
Program (#304) described on the World insecticide dips may change that.
Wide Web at http://www.ars.usda.gov/
programs/cppvs. htm.
Robert G. Hollingsworth is at the
USDA-ARS U.S. Pacific Basin Agricul-
tural Research Center, PO. Box 4459,
Hilo, HI 96720; phone (808) 959-4349,
fax (808) 959-5470, e-mail rolling@
pbarc.ars.usda.gov. *


Agricultural Research/September 2000










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A ll potatoes are related
to each other, more or
less. Some species
are like brothers and
sisters; others are
distant cousins. One very wild Botanist David Spooner (right)
resources specialist with the Inte
Mexican cousin is Solanum Peru, collect potato germplasm i
pinnatisectum. Found in and international gene banks.
central Mexico, this species
may be a good source of resistance against Phytophthora
infestans-the fungus that causes late blight. This disease
resulted in the 19th-century Irish potato famine.
Finding and making use of resistance to late blight is
important because the disease costs potato growers worldwide
about $3 billion annually, according to the International Potato
Center in Lima, Peru. Using fungicides to control recent attacks
has increased production costs by nearly $200 an acre for potato
growers in Idaho, Washington, North Dakota, Colorado,
Oregon, Minnesota, Michigan, Maine, and Wisconsin.
Now, new strains of late blight have emerged, the most recent
being US 8. Chemical control of these new strains is more
difficult and costly. That's why breeding resistance into potatoes
is being explored.

New Ways To Incorporate Genes
ARS plant geneticist Bob Hanneman and University of
Wisconsin graduate student Miguel Ramon in Madison,
Wisconsin, have developed new ways to incorporate the natural
resistance in wild Mexican species into commercial potatoes.
They have crossed a sexual hybridization bridge: Mating the
wild Mexican species-S. pinnatisectum-with a derivative
of a commercial potato variety, using a technique known as
embryo rescue. A hybrid from the rescue could be used as a
maternal parent in a mating with the cultivated potato.
"The group of Mexican species we are interested in have
two sets of chromosomes and are a rich genetic resource with
extreme resistance to viruses, insects, fungi, and nematodes,"
says Hanneman. "But they are difficult to cross with the
majority of other cultivated or wild species."
S. pinnatisectum is maintained at the U.S. Potato Genebank
in Sturgeon Bay, Wisconsin. ARS potato geneticist John
Bamberg manages the genebank, which receives and maintains
wild species from plant collectors like ARS botanist and plant
explorer David Spooner in Madison.
"The problem of incorporating useful genes from any wild
species is the various barriers to crossing with the cultivated
potato so that fertile hybrids can be obtained. Those hybrids
must be used in a breeding scheme that eliminates undesirable
traits contributed by the wild species," says Bamberg.
"To date, 16 wild species have been incorporated into com-
mercial varieties, but many more species have potential for


and
*rna
n P


Agricultural Research/September 2000


use in breeding," says Spooner.
Hanneman's early research
crossed non-tuber-bearing wild
potato species with other wild
species to find a way to access
Alberto Salas, plant genetic their germplasm by sexual
tional Potato Center, Lima,
eru for deposition in national means. S. verrucosum stood
out as a potential parent be-
cause of the good embryo
development of the hybrids," he says.
So Hanneman selected S. verrucosum to cross with the "un-
crossable" Mexican potatoes. This mating yielded several new
hybrids, which have since been crossed with a range of wild
relatives and with derivatives of commercial varieties.

Lots of Good Traits To Choose From
The wild Mexican species also resist early blight, which is
associated with dry weather. Typically, the disease is seen in
August when plants start to mature. The fungus Alternaria
solani-the culprit in early blight-causes problems similar to
those of late blight. But late blight attacks quickly and is capable
of defoliating a field within a matter of weeks. Early blight is
slower and progressive. Resistance to both diseases is needed
to reduce reliance on chemicals.
University of Wisconsin graduate student Joe Kuhl, work-
ing with Hanneman and ARS plant geneticist Michael Havey,
has advanced the research by identifying the chromosome in
S. pinnatisectum that confers resistance.
"We know there are a number of resistance genes in culti-
vated potatoes, but the fungus has matching genes that negate
the action of the host's resistance genes. That means eventually
the fungus may overcome this type of resistance. Ideally, we'd
like to find combinations of multiple resistance genes, which
could be more durable and not easily overcome by the fungus,"
says Kuhl.
The ultimate resistance test is always in the field. Last
summer, the researchers challenged the pinnatisectum hybrid
against late blight at the University of Wisconsin's Agricultural
Research Station in Hancock. It showed nearly 100 percent
resistance to late blight. In replicated trials, the hybrid was also
resistant to Colorado potato beetle, an insect costing U.S. pota-
to, tomato, and eggplant growers about $150 million annually.
-By Linda McGraw, ARS.
This research is part of Plant, Microbial, and Insect Genet-
ic Resources, Genomics, and Genetic Improvement, an ARS
National Program (#301) described on the World Wide Web at
http://ww.nps.ars.usda.gov/programs/cppvs.htm.
To reach the scientists mentioned in this article, contact
Linda McGraw, USDA-ARS Information Staff, 1815 N.
University St., Peoria, IL 61604; phone (309) 681-6530, fax
(309) 681-6690, e-mail lmcgraw@asrr.arsusda.gov.

9















small, blue packages,
and blueberries are a
superior example.
During the Civil War,
weary soldiers drank bever-
ages containing blueberries to
invigorate themselves after a
hard day's work. Native Amer-
icans once used the fruit to
make pemmican, a type of
meat jerky. Today, blueberries
are a popular ingredient in
muffins, pies, and even jelly.
Scientists at the ARS Small
Fruits Research Station in PEGGYGREB
Poplarville, Mississippi, have been
researching blueberries since the 1970s,
planting their first plants in 1971. It is
because of research accomplishments at
the ARS station that Mississippi started
growing blueberries commercially. Since
1984, Poplarville residents have held an
annual Blueberry Jubilee in honor of the
berry and its contribution to small farm
success.
"We have released six blueberry cul-
tivars to date," says horticulturist James
M. Spiers, who heads the Mississippi
unit. "Cultivar development takes a long
time, usually more than 10 years. Before
we release a new blueberry plant, we
want to know when the fruit ripens, that
the plants grow vigorously, and that they
produce high-quality fruit. Potential
cultivars are tested in a few locations to
determine climatic adaptability."
Biloxi, the newest blueberry, was
recently released in honor of Biloxi,
Mississippi's 300th birthday. It is an
early-ripening southern highbush culti-
var. Other ARS releases include Jubilee,
Magnolia, Pearl River, Cooper, and
Gulfcoast.
Southeastern growers produce two
types of blueberries: rabbiteye and south-
ern highbush. The rabbiteye type is more
vigorous. Native to the South, rabbiteye
is more adaptable to various soil types
and more drought tolerant, and the fruit
has a long shelf life. Southern highbush


cultivars ripen earlier than rabbiteye cul-
tivars and better fit the market window
for growers in the southeastern United
States. Most of the acreage in the South-
east is planted in rabbiteye cultivars, but
more growers are planting southern
highbush cultivars because of more fa-
vorable prices, Spiers says.


PEGGY GREB (K9045-1)


A newly release southern lnghbusn
cultivar called Biloxi ripens earlier than
most other blueberries and is adapted to the
Gulf Coast. Above, technician Cynthia
De Fouquette and horticulturist James
Spiers examine fruit from the new plant.


"Many southern blueber-
ry growers are small farmers
who average about $2,000 an
acre," notes Spiers. "The to-
tal acreage in Mississippi is
about 1,800 acres. Many of
these enterprises are small
pick-your-own, roadside, or
marketing cooperative-type
farms. These farmers simply
can't afford to lose their
crops or even part of their
crops to early freezes, in-
sects, or poor management.
We've been focusing on cul-
tivar development and im-
proving cultural practices, pest control,
and postharvest handling," he says.

The Latest Buzz
Blueberries are a seasonal fruit in the
Southeast, available from about the last
week of May through July. But there's a
lot of hard work that goes on long before
the berries become available. Blue-
berries need bee pollination, and unfor-
tunately, native bee pollinators are
lacking in many areas of the southern
United States.
"The most important pollinator in this
area is the southeastern blueberry bee,"
says Blair J. Sampson, an entomologist
with the Poplarville station. "These na-
tive bees are excellent pollinators but
very difficult to manage commercially.
They are ground nesters, so it's difficult
to control them and bolster their popu-
lation. Also, fire ants can be a problem
because they will attack the bee larvae.
I'm looking at the Osmia ribifloris bee,
which is easy to manage, as a possible
solution to the southeastern pollination
problem."
Native to the western United States,
the psychedelic bee looks like a throw-
back to the 1970s. It's a small desert
mountain bee with bluish-green irides-
cent features. Sampson acquired the bee
from fellow ARS entomologist James H.
Cane with the Bee Biology and System-
atics Laboratory in Logan, Utah. (For

Agricultural Research/September 2000






PEGGY GREB (K904B-1)
-%man~j


more information on bee pollinators, see
"New Pollinators Buzzing With Poten-
tial," Agricultural Research, May 2000,
pp. 4-6.) In its native range, the bee gath-
ers pollen from manzanita, a shrublike
tree with thin, reddish-brown bark and
flowers that closely resemble those of the
blueberry.
Sampson has had the solitary bee in
quarantine for a year. It takes about 300
bees, mostly female, to pollinate an acre
of blueberries. He's developing strategies
for growers to release and manage these
bees. He says they should be available in
2 years. "These bees have excellent po-
tential in this area because they have no
major natural enemies here," he says.
Sampson is also looking at ways to
control the blueberry gall midge, a fly
that attacks the flower and leaf buds of
blueberry plants. This pest is particularly
bothersome and hard to control. It's not
visible on the plants, and damage is often
mistaken for frost damage, so the plants
are not treated for the pest. It is a major
blueberry pest, causing crop losses of up
to 30 percent in Mississippi alone.
Sampson is turning to the midge's own
natural enemies for ecologically safe pest
control. "I've discovered possible new
species of parasitoid wasps that attack
midge larvae," Sampson says optimisti-
cally. He is working with ARS entomol-
ogist Michael E. Shauff, who is with the
Systematic Entomology Laboratory in
Beltsville, Maryland, to correctly identify
the wasps.
"Once we get them identified, we hope
to use them as biological controls for the
midge," says Sampson. "They develop
inside the bodies of the gall midge lar-
vae, eventually killing them."

Nutritious, Safe Berries
Blueberries have been noted as a good
source of dietary fiber and antioxidants,
such as anthocyanins-the source of their
pretty blue color, and vitamin C. These
antioxidants fight cell-damaging free rad-
icals. Blueberries also contain folic acid,
ellagic acid, and bacterial inhibitors. One


Agricultural Research/September 2000


cup of the berries contains
just 80 calories and 1 gram
of fat-making it a healthy
dessert or snack.
As if that weren't
enough nutrition packed in
one fruit, horticulturist
James B. Magee, also with
the Poplarville station, is
screening southern culti- The Osmia ril
vated and wild berries, in- pollination of
eluding blueberries, for Sampson insp
their potential to produce
resveratrol. Resveratrol
has been touted for its anticancer prop-
erties and cardiovascular benefits. He's
collaborating with chemist Agnes
Rimando, who is in the ARS Natural
Products Utilization Research Unit, in
Oxford, Mississippi.
"So far, searching for berries with high
resveratrol content has been like an ex-
pedition," says Magee. "But once we find
some, we hope to use them in our breed-


PEGGY GREB (K9047-1)

..q U


Technician Donna Marshall and
horticulturist James Magee measure
resveratrol content in blueberries.


uJloris bee is being developed for commercial
blueberry crops. Here, entomologist Blair
iects a nesting straw of the bee.



ing programs to develop cultivars that
will produce resveratrol in their fruit."
Magee is also conducting studies to
examine microbial populations in fresh
and frozen southern highbush and rab-
biteye blueberries. This information
about microbes can help processors de-
velop a Hazard Analysis Critical Con-
trol Points (HACCP) plan for their pro-
cessing plants.
"Microbial populations on the fruit
vary in numbers and types of organisms.
We want to know how these populations
are affected by processing and how they
may affect the end use of the berries from
quality and safety perspectives," says
Magee.
Total U.S. production for fresh and
processed blueberries was 180.2 million
pounds, valued at $156 million in 1999.
"Our goal is ensuring that a good, whole-
some market is available," says
Magee.-By Tara Weaver-Missick,
ARS.
This research is part of Crop Produc-
tion, an ARS National Program (#305)
described on the World Wide Web at
http://www.nps.ars.usda.gov/programs/
cppvs.htm.
James M. Spiers, James B. Magee,
and Blair J. Sampson are in the USDA-
ARS Small Fruits Research Unit, P.O.
Box 287, Poplarville, MS 39470-0287;
phone (601) 795-8751, fax (601) 795-
4965, e-mail
jspiers @ ars.usda.gov
jmagee@ag.gov
bsampson@ars.usda.gov. *






Pomological Watercolors:


A Wealth of Beauty and Detail


-Wlore Man 6,000 splendidawa/ercolors of
apples, L/acaoerries, cherries, grapes, per-
simmons, andoolferfruis arepreseroed al
Ife C7TS Calionaf/S-rcul/ura/li&'rary
i~n le/lsoile, -'ICryfanfd knownn as Iie
(Q/cOSZ) 7omoloy/ca/falercolor Collec-
lion, I s Ireasury oforiryia/prinhs and
relatedma/erials males up one of fle
wor/O's mosl unusua/lold- K9008-7
inys of/ale 1! and ear{y 3
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olanica/ilfus/raions.
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Io depicl-wil/ aaso/ule
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deoveopedor perhaps ga/Ieredoluriny
overseas plan/-co/lec/ing expeditions.
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firary's specia/colleclions, "'47ese earfy
researchers could '/us/pic4 up a ,andy
camera and'pop in a rol/ofco/or film. So,


Leyinniny in 1887, '(WST's Diuision of
Jomoloyy Airedsiff/edarfisls who created
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up /Ae collection.
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prints were fealuredoin early '(ZlI7ipuo/i-
ca/ions, iclu/uoiny 6ullelns andcirculars /or
farmers, as we//as annua/repor/s. /ooday,
Ale drawuinys are a Loon lo Lorfi-
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andfpuh'Lers. J9ese spe-
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rely on AIe reaks/ic -i//us-
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source ofin/ormaibon
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isures of the National Agricultural Library


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Agricultural Research/September 2000


S9 .


K9008-1


Treat


K9008-11
4


2 t"






i ". >


(C













K9008-3


6





In the late 1800s and early 1900s, USDA hired
new varieties of fruits and nuts. The result was
precise renderings that serve as accurate record
artists, Amanda A. Newton, was the granddaug
Commissioner of Agriculture.



K9008-7












1. Hoosier raspberry (artist E. chutt
2. Pan American strawberry (artist .A Ne'.. in 4
3. American Beauty apple (artist A.A. zw
4. Bachman's Grape #309 (artist R.G. lrejadrrmni
5. Wineberry raspberry (artist W.H. Prestele)
6. Fuyu persimmon (artist R.G. Steadman)
7. Schaffer raspberry (artist A.A. Newton)
8. Princess Ena strawberry (artist D.G. Passmore)
9. Rubusfruticosa blackberry (artist A.A. Newton)
10. Delaware x Gor Ross grape (artist E.I. Schutt)


Agricultural Research/September 2000


about 50 illustrators to produce watercolors of
a collection of thousands of beautiful and
s of the fruits of that era. One of those prolific
hter of Isaac Newton, the nation's first


K9008-9


K9008-15


K9008-5


-r-r








Transgenics for a Better Tomato



SCOTT BAUER (K9026-1)

planted and harvested their
crops, they knew little about
the science involved. Nor
did they have a large seed -
stock. But today, science is
helping farmers improve
their seed selection. As a result, consum-
ers have access to a wide variety of safe,
plentiful, and nutritious foods. In the fu-
ture, new biotechnology tools like genet-
ic engineering can help plant breeders
continue this trend.
Scientists like ARS plant physiologist
Autar K. Mattoo know the powerful con-
tributions that science and technology
can make to the world's food supply.
"Our goal is to develop plants for im-
proved nutrition, longer shelf life, and
resistance to harmful pathogens," says
Mattoo, who heads the ARS Vegetable--
Laboratory in Beltsville, Maryland.

Better, Faster, With More Precision
"A traditional breeding approach can
require 10 to 15 years to release a new
tomato variety. This time can be cut to
less than half using biotechnology," says
Mattoo. And he has done just that. He
has developed several new transgenic
tomatoes in almost half the time.
Traditional breeding requires select-
ing a tomato species that has a desirable
trait, such as early ripening, and cross-
ing it with another tomato species that
has a good genetic background. The de-
sired result is an earlier ripening tomato
that makes it to the market sooner.
Mattoo points out that the goal of a
biotechnological approach is no differ-
ent-the process involved is just more
precise.
"In the transgenic approach, we find
a particular gene that controls the trait
we're interested in, like early ripening
or prolonged shelf life," he says. "Then,
using molecular tools, we reengineer the
gene, confirm it's what we want, and
introduce it into a plant so it becomes In a greenhouse of the ARS Vegetable Laboratory in Beltsville, Maryland, plant
part of that plant's genome. The plant physiologist Autar Mattoo examines tomato plants genetically engineered to enhance
then possesses the new trait." phytonutrient content and longevity of the fruit.


Agricultural Research/September 2000













Traditional breeding allows trans-
ferring hundreds of genes in a relatively
random manner. Good or bad traits are
sometimes haphazardly passed along to
the new plant. With genetically engi-
neered plants, however, scientists know
exactly what's going into the plant and
what traits will be expressed by the
transformed plant.

Tomatoes With Staying Power
If the season is right, you may find a
brilliant red tomato sitting on a table in
Mattoo's office. The tomato might look
like it was just picked, but chances are
it's one of his transgenic tomatoes that
has been sitting there for weeks.
In collaboration with a Purdue
University scientist in West Lafayette,
Indiana, Mattoo has developed a novel
means for slowing ripening by intro-
ducing a gene that controls only this
function. He has been perfecting his
technique for creating transgenic vege-
tables for the last 8 years-in Beltsville
and West Lafayette.
Mattoo's new transgenic tomatoes
have 2.5 times more lycopene than non-
transgenic tomatoes. Lycopene is a
carotenoid that has strong antioxidant
properties. Antioxidants prevent oxygen
radicals from causing damage in cells.
Carotenoids aid in preventing early
blindness in children, preventing cancer,
enhancing cardiovascular health, and
slowing aging. Not only are the trans-
genic tomatoes richer in lycopene,
they're also more robust and more solid
compared to traditional tomatoes.
Another tomato genetically engi-
neered by Mattoo has a longer shelf life.
Its cell membranes deteriorate more
slowly during and after ripening. "The
plants bearing these tomatoes bloom
three or four times over the season," he
says, "whereas regular tomatoes normal-
ly produce just two harvests."
In a plant, thousands of genes control
many functions. "Some genes are 'turned
on' only at a certain developmental stage
or in response to an environmental cue.


Agricultural Research/September 2000


SCOTr BAUER ( ,.9 .


An X-ray J1i7m
confirms that an
engineered gene
called aye geneSAM
introduced into the
tomato Plant,
itis Posed to. The
gene is expressed in
only the fruit, and
ot in the stem, leaf,
or ifower.







Other times they're simply
turned off," says Mattoo. "Using genetic
manipulation, we can turn these genes
on or off at any particular time during
growth and development. The genes we
introduce into tomatoes are not always
switched on. They come on only when
engineered to do so, for instance, only
when the fruit starts ripening."

Mailing Genes to the Correct Address
Mattoo has a passion and a gift for
discovering how plant cells work and for
creating easy-to-use methods for im-
proving vegetable production. His latest
endeavor is to "mail" the protein product
of a beneficial gene to a specific location
within a plant cell so that the protein will
be more useful for the crop.
In this "ZIP Code" system, as Mattoo
refers to it, the gene is constructed so
that it carries with it a defined DNA
sequence that, when translated by the
cell, produces a protein with an added
signal defining the protein's destination.
This signal guides the new protein to its
proper spot in the plant cell.
This ZIP Code system has been
shown by other scientists to work like
the Post Office ZIP Codes, in that the
destination signal is set in place before
gene transfer. This method ensures that
the product of the new gene will not end
up at a place in the cell where it could
be damaged. The system can work with
many fruits and vegetables.
With the new transgenic foods,
Mattoo says the genetic material can be
engineered so that it is expressed only
under controlled conditions. Each gene
is carefully reconstructed to check that
all the elements are in place and in sync.


I,


7P '


No single block is left unchecked.
"Imagine construction of a bridge,"
says Mattoo. "The engineer has to ensure
that all parts are properly placed and
aligned. Any single misstep can undo the
bridge. Similarly, genes used to produce
transgenic crops are vigorously tested and
all elements checked."

Strict Safety Precautions Followed
Mattoo's newly modified tomato has
some advantages, such as reduced
spoilage and increased nutritional and
health benefits. But before it can be made
available as a food, it will undergo
rigorous testing for health and environ-
mental safety.
"The public's confidence in food
safety is too important to compromise,"
says John W. Radin, ARS national
program leader in Beltsville, Maryland.
"This type of product, however, repre-
sents the next generation of genetically
engineered foods. It will bring to the
consumer's table important benefits that
could not have been achieved using
traditional breeding."-By Tara
Weaver-Missick, ARS.
This research is part of Plant Bio-
logical and Molecular Processes, an ARS
National Program (#301) described on
the World Wide Web at http://www.nps.
ars. usda.gov/programs/cppvs. htm.
Autar K. Mattoo is located at the
USDA-ARS Vegetable Laboratory, 10300
Baltimore Ave., Bldg. 10-A, Beltsville,
MD 20705; phone (301) 504-7380, fax
(301) 504-5555, e-mail amattoo@asrr
arsusda.gov. *


)







Rotate To Prevent Replant?


rowers of the nation's largest
crop of apples-in Washington
State-may benefit by planting
another top Pacific Northwest
commodity: wheat.
But the wheat in this case wouldn't
be a typical for-profit crop. Grown
instead as a rotation or cover crop in the
orchard, it might help prevent replant
disease, a crippling condition that strikes
young orchards. And it could serve as
an alternative to methyl bromide and
other soil fumigants typically used to
sterilize old orchards before planting
new trees.
The idea comes from Mark Mazzola,
a plant pathologist at the Agricultural
Research Service's Tree Fruit Research
Laboratory in Wenatchee, Washington.
He's discovered that in the Pacific North-
west, replant disease seems to be caused
by buildup of a complex of four types of
soilborne fungi: Cylindrocarpon, Phy-
tophthora, Pythium, and Rhizoctonia.
"Apple trees seem to change the soil
in a way that favors these pathogens,"
Mazzola says. "Some wheat varieties, on
the other hand, modify the soil environ-
ment to the benefit of different microor-
ganisms."
Specifically, he found a bacterium in
some wheat soils, Pseudomonas putida,
that can protect young apple roots from
these fungi. ARS has patented use of a
strain of this bacterium to prevent replant
disease.



When nothing is done between tak-
ing out an old orchard and putting in a
new one, the young trees often become
stunted and their root systems are small
and decayed. For years, scientists have
debated whether the cause was biologi-
cal-a disease or organism-or a result
of abiotic factors such as soil chemistry.
"Since methyl bromide and fungi-
cides that suppress microbes seem to
improve apple trees' health, it now looks
like the cause is something biological,"


says Mazzola. "That cause may vary
from place to place. In the Northeast, for
example, nematodes may cause a prob-
lem. Here in Washington, specific groups
of fungi seem to be the primary culprits."
But methyl bromide is due to be
phased out by 2005. Other common pes-
ticides used in the Northwest's orchards
may also be taken off the shelf because
of environmental concerns. For that rea-
son, and to support the region's organic
growers, Mazzola is looking for a
nonchemical approach to prevent replant
disease.
And his search is becoming more ur-
gent all the time.
"Years ago, growers might have left
an orchard in for several decades," Maz-
zola says. "But to meet market demands,
some growers now pull out old orchards
and plant new varieties much sooner."
Growers produce at least a dozen
commercial varieties in Washington's
billion-dollar-per-year apple industry.
About half of the nation's apples are pro-
duced here on about 180,000 acres.
About 10,000 acres of apples are replant-
ed each year.




If a new orchard is planted on ground
that was previously used for something
else, the harmful fungi don't build up fast
enough to hurt the trees before they get
established. But if trees are planted into
an existing or previous apple orchard, the
fungal population prevents the young,
new trees from growing well.
It is accepted among scientists that
chemicals exuded from plants affect the
soil that surrounds them, favoring spe-
cific populations of microorganisms.
Although the specific selective chemicals
have not been identified, Mazzola has
found that after an orchard has been in
place about 3 years, apples promote a
fungal population that can cause replant
disease. He's studied 18 orchards in
Washington, in collaboration with


Wenatchee Valley College and David
Granatstein, director of Washington State
University's Center for Sustainable
Agriculture and Natural Resources in
Wenatchee.
Now Mazzola is looking at how long
wheat would have to be grown as a rota-
tion crop to change the soil microbial
community enough to stave off replant
disease. Alternatively, he'll look at
whether growing the wheat as a cover
crop in existing orchards can reduce fun-
gal populations sufficiently to allow new
trees to grow well. He doesn't anticipate
that apple growers would harvest the
wheat as a crop, but says that would be
up to the individual.
Theoretically, if young trees are given
a good start, they'll be able to grow-
despite the harmful fungi-when they're
older. But Mazzola speculates that con-
tinuing to keep populations of these fun-
gi low might improve yield, even in ma-
ture trees. Although greenhouse tests
have indicated the strategy has merit, he
doesn't advocate that growers abandon
fungicides and rely on wheat until he has
conclusive evidence in a field situation.
"Washington has a progressive apple
industry, and they're really interested in
this work," Mazzola says.
Next he'll try to identify why some
wheat cultivars work while others have
little or no effect. So far, he hasn't found
any commonality among wheat types-
such as hard red or soft white-only that
some varieties provide a good environ-
ment for P putida while others don't.
-By Kathryn Barry Stelljes, ARS.
This research is part of Plant Disease
(#303) and Methyl Bromide Alternatives
(#308), two ARS National Programs de-
scribed on the World Wide Web at http://
www. nps. ars. usda. gov/programs/
cppvs.htm.
Mark Mazzola is with the USDA-ARS
Tree Fruit Research Laboratory, 1104 N.
Western Ave., Wenatchee, WA 98801;
phone (509) 664-2280, fax (509) 664-
2287, e-mail mazzola@tfrl.ars.usda.
gov. +

Agricultural Research/September 2000














BRIAN PRECHTEL (K9032-1n


t gis M la p s t e a w ri n t pl
Te r s l e e e to n w e e o cp e
that~~~~~ cuerp latdsse

Below '.left:~dVA Mazz la measI.~urestun iamte asll an5 lini cao of growth Iat I1'SU Iin re s from'S wheat rotatU~ionIis.
Beo Siht Iehica S i Io use gas cho aogah to Idntf batraioltdfo aperos


Z~~ ~~ rAIIf f


BRIAN PRECHTEL (K9028-1)


o -nlM rncln I L (PaoU -1)

Agricultural Research/September 2000





New NC-7 Web Site

Locate Outstanding

Woody Ornamentals-

Online


information on new trees, shrubs, vines, and ground-
covers to plant is as nearby as their computers.
Agricultural Research Service scientists have
created a unique web site with vital and extensive
information on over 175 kinds of woody plants with potential
ornamental use.
"Details on how these plants perform and evaluations of
their aesthetic and adaptive characteristics are just some of the
many reasons gardeners will find the site important," says ARS
horticulturist Mark P. Widrlechner. He and ARS technician A.
Paul Ovrom at the North Central Regional Plant Introduction
Station in Ames, Iowa, developed the web site to make the
information accessible to the general public. Ovrom created
and designed it.
Data for the site come from a cooperative project funded by
the U.S. Department of Agriculture and 12 state agricultural
experiment stations in the north central States. Since historically
it's the seventh such project in the region, it is commonly
referred to as the NC-7 Project. Its official title, "New Crops -
The Introduction, Multiplication, Evaluation, Preservation,
Cataloguing, Enhancement, and Utilization of Plant
Germplasm," describes the range of activities managed at the
Ames station. Widrlechner and Ovrom, who conduct the
horticultural project at the station, gather and disseminate the
data from ongoing NC-7 trials on woody
landscape ornamentals.GY GREB (K9037
"Our NC-7 web site includes an
overview of the trials, a list of the regional
cooperators, plant descriptions, evalua-
tion summaries, tables of the 10-year
evaluation data collected and compiled
from the cooperators, and pictures of
many of the plants," says Widrlechner.
"We rely heavily on our network of
horticultural cooperators located at sites
scattered across the region and in other
states with similar climatic
characteristics."
Widrlechner coordinates the cooper-
ator network, guided by a committee of
representatives from the participating
state agricultural experiment stations.
Emphasis is on detailed, long-term
evaluations by cooperators at 36 sites in
Alaska, Colorado, Connecticut, Illinois,
Indiana, Iowa, Kansas, Maine, Michigan, Saplings of Manchuri
Minnesota, Missouri, Nebraska, New (Acer tegmentosum) a
Hampshire, North Dakota, Ohio, South research aides Scott
Dakota, and Wisconsin. Oltmans for shipment


NC-7 woody ornamental trial plants growing at a research farm
at Iowa State University. In the center is a white fringetree,
Chionanthus virginicus, in full bloom.


an st
re pr
Vike
ttoa
'.i1n


Started in 1954, the north-central project trials are one of
the longest running landscape plant evaluation networks in
the United States. They address some of the landscape horti-
culture needs of the north central states and other parts of the
country with similar challenging growing conditions.
"The region's climate is one of extremes, and many parts
have alkaline soils that developed under
grasslands. So there's less diversity here in
commercially available woody plants adapted
to the area than is found in most other parts of
our nation," says Widrlechner. "Because of the
/_ broad range of environments found among the
trial sites, it is unusual for any particular trial
plant to perform well at most of them, so
system-wide releases are difficult," he says.
"But when plants perform especially well, we
encourage trial-site cooperators to introduce
the new plants to the nursery industry and
ultimately to the general public."
Official releases are made through the
cooperators' institutions, rather than through
the ARS Plant Introduction Station.
Since many of the cooperating sites have
participated in NC-7 since the 1950s, they have
developed extensive collections of interesting
plants. "These plants are available for public
Sm observation and teaching," says Widrlechner.
riped maple "They're often featured in field days for the
prepared by
and Sheilah benefit of local nursery and landscape
cooperator workers."
I _+,


al r a. na Iu p H a. .


Agricultural Research/September 2000





































Where Trial Plants Come From
New plants for the NC-7 trials are acquired in many ways.
Three of the most common are through USDA-supported
exploration, seed exchange, and donation. Germplasm
collections are part of the U.S. National Plant Germplasm
System and serve as important sources of genetic diversity for
researchers worldwide.
As one of the world's active gene banks,
PEGGY GREB (K9034-1)
the North Central Regional Plant Intro-
duction Station provides about 20,000 ---
samples of germplasm free to researchers
around the world each year. As a courtesy,
many researchers who have received seeds
reciprocate by sending the Ames station lists -
of seeds collected by their personnel. '
"Occasionally, direct donations come
from institutions with large numbers of extra
plants after exploration. More often, they're '
propagated by originators of new selections
who are seeking advanced testing in the NC-
7 trials. During the last decade, selected
plants or cuttings donated for testing have
come from commercial nurseries and
university research projects, the USDA's
Natural Resources Conservation Service
(NRCS), and Agriculture Canada," says
Widrlechner. "The NC-7 trials also provide
horticulturists and nursery workers Horticulturist Mar
throughout the region with an early and technician Pat
examination of new releases from other seedlings of woody
institutions." will be included in


-kV
l O
orn
the


NC-7 woody ornamen


Since 1954, over 550 accessions have been distributed for
testing to participating cooperators at the 36 trial sites. About
half were trees-both evergreen and deciduous; 40 percent
were shrubs; and the rest were vines, groundcovers, and her-
baceous perennials.
Each year, Widrlechner and Ovrom assemble a collection
of about 8 to 15 new items for testing. During winter, they
send each cooperator a descriptive list of these plants. The co-
operator selects plants to be tested at that site.
"Come spring, we ship or hand deliver the plants to the sites.
The cooperators then plant, observe, and evaluate the selec-
tions through the seasons and prepare performance reports at
1, 5, and 10 years after planting. These are sent to the Plant
Introduction Station for recording," says Ovrom.
Widrlechner has identified some current trends in the land-
scape and nursery industries likely to influence introduction
of new plants. "Ideally, we choose trial plants that can meet
changing needs," he says.

Guide to the Web Site
According to Ovrom, the NC-7 trials' web site includes in-
formation about how a new plant may be an improvement over
currently available ones. This might be because of aesthetics
or adaptation, based on experience with new plants at one or
more sites, or derived from hypothetical performance of wild
plants based on the climate and soil of their native habitats.
"Users can click on a hot link to a summary and find plants
suitable to their location or find trial site
S locations and cooperators' names and e-mail
addresses. Cooperators are hot-linked to
places where they work-like an arboretum,
Sa botanical garden, a state experiment
station, or a plant materials center operated
by NRCS," says Ovrom.
Visit the NC-7 web site at http://www.ars-
grin.gov/ars/MidWest/Ames/trialhmpge.
.- html.-By Hank Becker, ARS.
fThis research is part of Plant, Microbial,
and Insect Genetic Resources, Genomics,
and Genetic Improvement, an ARS National
Program (#301) described on the World
Wide Web at http://www.nps.ars.usda.gov/
programs/cppvs.htm.
Mark P Widrlechner and A. Paul Ovrom
are at the USDA-ARS North Central Region-
al Plant Introduction Station, Iowa State
University, Agronomy Hall, Room G-212,
Vidrlechner (left) Ames, IA 50011-1170; phone (515) 294-
vrom examine 3511/3454, fax (515) 294-1903, e-mail
lamentals that n
USDA-ARS nc7mw@ars-grn.gov
tal trials, nc7ao@ars-grin.gov. *


Agricultural Research/September 2000







































B means and cornbread-a Satur-
day night staple in many parts
of the country. But who really
cares beans about this homely,
low-cost food?
Well, many of us do. As
Americans have become more
health conscious, we've consumed more
beans. Today, we eat almost 8 pounds
per person each year. Pinto and navy
beans account for 5 of those pounds,
eaten mostly as refried beans pintoss)
or as canned pork and beans (navy).
In all, U.S. growers harvested over
3 billion pounds of edible dried beans
in 1998, worth over $600 million. But
despite beans' familiarity and populari-
ty, few of us are aware of the surprising
amount of science to be found in an in-
expensive can full of convenience and
nutrition.
Key players in this science are the
plant breeders who painstakingly work
at developing new varieties with
characteristics important to growers,
processors, and consumers. North
Dakota State and Michigan State
universities have the two largest such
programs in the country, both breeding


varieties in all market classes of U.S.
beans. But they are two of just a few bean
breeding programs.
"We're lucky if there are a half-doz-
en centers in the United States," says Ken


Grafton, a breeder at North Dakota State.
Nevertheless, in any large super-
market, shoppers should be able to count
at least 10 different kinds of beans-
known in the bean world as market


Geneticist George Hosfield (left) and former research associate Clifford Beninger prepare
bean extracts for analysis of phytochemicals and other nutrients using high pressure liquid
chromatography.


Agricultural Research/September 2000











FLAVONOIDS: The Unexpected Bean Ingredient


classes because each has its own distinct
market and uses-small white, black,
cranberry, dark-red kidney, great north-
ern, light-red kidney, navy, pinto, small
red, and yellow eye. Even smaller
supermarkets will have close to 10-
some of them in packaged mixtures, like
a colorful, dry minestrone soup mix with
small reds, great northern, and light-red
kidney beans.

A Quarter Century of Research
At the Bean and Beet Research Unit's
Quality Laboratory in East Lansing,
Michigan, Agricultural Research Service
geneticist and breeder George L.
Hosfield has been upgrading the color,
canning quality, and other quality
characteristics of beans-as well as their
nutritional value-for the past 24 years.
If the small reds in that bag of mine-
strone mix are LeBaron Red, a variety
recently released for the Pacific North-
west, they are the first upright small reds
bred for superb canning quality and re-
sistance to bean common mosaic virus,
a major bean disease. Hosfield trans-
ferred the genes for erectness, canning
quality, and virus resistance into red bean
germplasm, which Phil Miklas, an ARS
geneticist in Prosser, Washington, then
used to create LeBaron.
LeBaron also has other desirable and
unique characteristics for red beans. For
one, it grows so quickly that farmers in
certain areas can plant it after early-
grown vegetables like peas for a second
crop in the same season.
"LeBaron is part of the first wave of
red beans emerging from Hosfield's
germplasm," Miklas says. "Because of
its unique disease resistance, exceptional
seed appearance, and canning quality, I'll
probably never release another small red
variety without using germplasm that
Hosfield developed," says Miklas. Small-
er than kidney beans and shaped like
pintos, 90 percent of red beans come
from Washington and Idaho.
Prosser is one of four ARS centers
for bean breeding research; the others are

Agricultural Research/September 2000


People who pay attention to the colors of the foods they cook and serve are
enhancing not only visual and gustatory pleasure, but nutritional punch as well.
Red grapes, oranges, pink grapefruit, strawberries, blueberries-all these foods
contain colored pigments with nutritious cancer- and heart-disease-fighting com-
pounds called flavonoids. These are the anti-aging antioxidants that may be respon-
sible for the so-called "French paradox"-how the French tend to have fewer heart
attacks and cancers, despite consuming high-fat diets. It's believed that the protec-
tive factor could be flavonoids in the skins of red grapes or the wine made from
them. Flavonoids are also known to be in many other fruits and vegetables, as well
as green and black teas and soy protein.
Now, Agricultural Research Service food quality geneticist and plant breeder
George L. Hosfield has found these flavonoids in bean seed coats, which is where
bean colors are also found. Certainly beans come in a mosaic of colors that can rival
those of fruits and vegetables-from the plain white great northern and navy beans,
to the mottled brownish pink pintos, to the cranberry bean's cream color with red
streaks and flecks, the light and dark reds of kidney beans, the maroon-red adzuki,
all the way to the black bean.
The bean industry has exacting standards for maintaining these colors. "It's so
strict," says Hosfield, "that pinto beans, for example, have to not only have just the
right brown mottling and shades of pink, but also show a yellow rim around the
'belly button,' or scar, where the bean was once attached to the pod.
"We know all eight genes that code for bean color, but we don't know how they
work," Hosfield says. "Now we're trying to figure that out, as well as identify and
learn the function of the genes for canning quality, disease resistance, and nutrition.
And we're searching for links between these qualities and bean color."
The seed coat, which is 10 percent of the bean, is not only high in antioxidants
for some beans, but is also where the high fiber content of beans comes into play.
It was Hosfield who found the antioxidants in the bean coat. He and colleagues
removed the coating and made it into an extract, which they freeze-dried. Then they
analyzed the constituents. They found eight flavonoids, PEGGY GREB (K8794-1)
six of which were particularly strong antioxidants.
They also found a genetic link between bean color and
the flavonoids. And they found a link between one fla-
vonoid and resistance to bean mosaic disease. This is
the first time a specific flavonoid association has been
found with a bean color gene.
Using modern molecular genetic technology, phar-
maceutical firms could mass-produce these flavonoids
if they choose, adding beans to the growing list of foods -
used to make flavonoid supplements, now that Hos-
field and colleagues have begun to break their genetic
codes. Breeders could increase the amount of fla-
vonoids in beans through traditional breeding or ge-
netic engineering, or a combination.
Hosfield's work is inspiring other scientists to find Biological aide Tonya Kane
ways to boost the high nutritional value of beans, prepares to perform an
antioxidant assay.
possibly leading to even more iron, other vitamins and
minerals, and antioxidants in the legumes. That's why
Hosfield is excited about the high levels of antioxidants he's found in small red, red
kidney, black beans, and pintos. And it's why he's passionate about the health benefits
of eating beans and getting them the respect they deserve.-By Don Comis, ARS.















Now standard, the tests developed by ARS geneticist George Hosfield and Mark Uebersax of Michigan State
University determine whether a potential new bean variety can keep its good qualities while being cooked,
soaked in brine or broth, sealed in a can, and stored on grocery shelves.


in Maryland, Michigan, and Puerto Rico.
Hosfield and three other geneticists from
ARS-one at each center-develop
germplasm that provides a good starting
point for breeders. Their work provides
important basics, like good yield, disease
resistance, processing quality, and up-
right growing habits.
Shree Singh, a breeder who operates
a bean nursery in red bean country at the
University of Idaho, says that Hosfield's
work is "of immense value to us. Hos-
field is the only person working on bean
quality, and he and Miklas are the only
geneticists working on small red bean
improvement-a neglected market class.
"Each of the four ARS geneticists
does something very different," Singh
says. "Their work is very complementary
to ours, and they give us free germplasm
that is not readily available, like that for
improved small red beans.
"Private and public breeders through-
out the United States and Canada send
seeds of potential new varieties to my
nursery for field-testing," says Singh. "I
harvest new seed and send it to Hosfield,
who then tests its canning qualities for
me. Then I publish the results and share
the information with public and private
breeders. We are very fortunate to have
this ARS support."

But Can They Take the Heat?
One of the most important attributes
of any new bean variety is its suitability
for processing.
"No one wants to open a can and find
the beans mushy or split open, with
starch leaching into the brine or tomato
broth that they're packed in," Hosfield
notes.


So in the 1980s, he and Mark A.
Uebersax, of Michigan State
University's Department of Food
Science and Human Nutrition, devised
a series of tests for beans. Now standard,
the tests determine whether a potential
new bean variety can keep its good
qualities while being cooked, soaked in


PEGGY GREB (K8791-1)


The seed coat of the red kidney bean
contains the color of the bean and is high in
antioxidants.


brine or broth, sealed in a can, and stored
on grocery shelves. The tests simulate
the exact conditions under which the
bean must be cooked and canned to
ensure consistent quality.
Breeders like Ken Grafton at North
Dakota State University nervously await
word from Hosfield about how a new
bean holds up under high heat. He says
the canning test is very important to
breeders around the world.
"We can't tell by the plant's per-
formance in the field how it's going to
survive the process," Grafton says. "It's
only at the canning stage that we find
that out." By then, breeders have in-
vested at least 3 years of work.
More likely than not, most of the


canned bean varieties on grocery shelves
were first evaluated at Hosfield's small-
scale cannery in his lab. His tests are used
to develop the two to four new dry bean
varieties released each year by the
Michigan State University/ARS breed-
ing team, which is headed by MSU
breeder Jim Kelly. All of the varieties
released by the team have excellent
canning qualities. Some of these varieties
include Huron and Mackinac navy beans,
Redhawk dark-red kidney beans, and-
this year-Jaguar and Phantom black
beans. The tests are models for other
canning quality tests used nationally and
internationally.
Now Hosfield has found molecular
markers for some of the canning charac-
teristics of navy beans. And he's search-
ing for more markers that could help
breeders eliminate some of the guess-
work from the canning test-as well as
improve beans' already high nutrient
content and the plants' resistance to
diseases.-By Don Comis, ARS.
This research is part of New Uses,
Quality, and Marketability of Plant and
Animal Products, an ARS National
Program (#306) described on the World
Wide Web at http://www.nps.ars.usda.
gov/programs/cppvs. htm.
George L. Hosfield is in the USDA-
ARS Sugarbeet and Bean Research Unit,
Michigan State University, 494 Plant and
Soil Sciences Building, East Lansing, MI
48824-1325; phone (517) 355-0110, fax
(517) 337-6782, e-mail hosfiel2@pilot.
msu.edu.
Phillip N. Miklas is in the USDA-ARS
Vegetable and Forage Crops Production
Research Unit, 24106 North Bunn Rd.,
Prosser, WA 99350-9687; phone (509)
786-3454, fax (509) 786-9277, e-mail
pmiklas@ beta.tricity.wsu.edu. *

Agricultural Research/September 2000








ScienceUpdate


Pest's Peptides Could Cramp
Its Style
Peptides, compounds that may play
important roles in controlling feeding and
reproduction, have been detected in
extracts from an important soybean pest.
Soybean growers currently use resistant
varieties and crop rotation to battle their
greatest foe, the soybean cyst nematode.
This microscopic, wormlike parasite
costs growers about $1.5 billion annually.
But resistant varieties are not effective
against all races of the nematode and
usually yield less than susceptible vari-
eties do when nematodes are absent.
The discovery of these peptides in par-
asite extracts opens a new path for sci-
entists who are investigating naturally
based controls for soybean cyst nema-
todes. The key may be the peptides' po-
tential involvement in regulating nerve
transmission and muscle activity in these
pests, as well as their feeding and move-
ment. At least three different peptides
have been observed in the nematodes
grown on soybean plants. The peptides
in soybean cyst nematodes differ from
those in nonparasitic species, and their
levels vary during the worms' develop-
ment. Researchers are focusing on those
which would be most active in female
nematodes, since they will lay the eggs
that yield new generations of hungry,
root-eating offspring. Edward P. Masler,
USDA-ARS Nematology Laboratory,
Beltsville, Maryland; (301) 504-8732,
e-mail maslere@ba.ars.usda.gov.

Vetch-a-Matic Beetle Control
A recent study showed that an organic
mulch made from a cover crop of hairy
vetch can reduce Colorado potato beetle
damage. This notorious pest ravages
potato, eggplant, and tomato crops,
causing annual crop losses and insec-
ticide-related expenses. Many growers
are using imadacloprid, a new systemic
insecticide that provides excellent
control. But the pest also has a proclivity
for developing resistance to insecticides,
so there is concern that appropriate

Agricultural Research/September 2000


Damage from Colorado potato beetles can
be reduced by planting tomato seedlings
into a mulch residue of hairy vetch.
measures be taken to prevent that. A
nonchemical control such as hairy vetch
mulch could be a useful part of a
sustainable integrated pest management
strategy for Colorado potato beetles.
In the study, hairy vetch was planted
in the fall; then the vetch was mowed and
killed in the spring before tomatoes were
transplanted into it. The vetch impeded
the beetles' movement and, since it is a
legume, added nitrogen to the soil. Fewer
beetles infested tomatoes transplanted
into the mulch, compared to tomatoes
transplanted into black plastic mulch.
And yields of staked, fresh-market toma-
toes grown in the mulch were compa-
rable to yields from insecticide-treated
fields. Kevin Thorpe, USDA-ARS Insect
Biocontrol Laboratory, Beltsville,
Maryland; phone (301) 504-5139, e-mail
thorpe @asrr.arsusda.gov.

For Better Surface Water
Quality, Dig Ditches
Drainage ditches are a common
feature in the agricultural landscape.
They carry runoff water from fields after
heavy rains. Now a first-of-its-kind study
that looked at the transport and fate of
two pesticides in vegetated agricultural
drainage ditches suggests they're valu-
able tools for reducing the amount of
chemicals that enter bodies of water.
Researchers simulated storm runoff
events in order to evaluate the role of
edge-of-field best management practices
in preventing potential contaminants
from leaving agricultural lands.


The researchers attempted to pinpoint
the test ditch's efficacy in keeping irri-
gation water and pesticides from getting
into water bodies. They found that it
trapped 60 to 90 percent of the herbicide
atrazine and a commonly used insec-
ticide Karate carried in runoff water. Its
vegetation enabled it to work like wet-
lands to sequester storm runoff materials.
Thus, ditches appear to be a simple, low-
tech, inexpensive way to improve surface
water quality. Farmers and conser-
vationists who want to reduce the chem-
icals, nutrients, and sediment leaving
their fields may find maintaining ditches
a practical and effective alternative
management practice. Matt Moore,
USDA-ARS National Sedimentation
Laboratory, Oxford, Mississippi; phone
(601) 232-2955, e-mail moore@sedlab.
olemiss. edu.

Better Retting for a Fledg-
ling Flax Industry
A new retting process could revolu-
tionize linen fabric production in the
United States. Enzymatic retting uses a
chemical to break down calcium bonds
in the flax plant, allowing easier loos-
ening of flax fiber so it can be extracted
from the plant and processed into linen.
Researchers have an agreement with the
Center for American Flax Fiber to evalu-
ate the process. They will also establish
standards for fiber strength, length, fine-
ness, nonfiber content, and color.
North America is the largest producer
of flaxseed and related products that
yield millions of tons of fiber. But only
a fraction of it is used for industrial pur-
poses. The nation now imports about
$150 million of flax fiber, flax fabric, and
flax-containing yarn annually-which
are converted into about $500 million in
finished products. Scientists hope
enzymatic retting will help establish a
domestic flax fiber industry. Danny E.
Akin, USDA-ARS Richard B. Russell
Research Center, Athens, Georgia; phone
(706) 546-3482, e-mail deakin@qaru.
ars. usda. gov.







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