Group Title: Agricultural research (Washington, D.C.)
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Title: Agricultural research
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United States -- Agricultural Research Service
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Full Text
U.S. Department of Agriculture Agricultural Research Service October 1997
Agricultural Research


Going Areawide
Makes IPM Goal
In 1994, the U.S. Department of
Agriculture set the ambitious goal of
implementing integrated pest man-
agement (IPM) on 75 percent of the
nation's farmland by the year 2000.
That goal seems more attainable
when one realizes that by IPM's
common definition, farmers have
already implemented the program on
half of their croplands. It describes
IPM as a system combining many
crop pest control strategies with
careful monitoring of both the pests
and their natural enemies.
But that definition has been
viewed as being too broad. So USDA
will issue a new working definition
for IPM later this year-one that
spells out the specifics of a variety of
Meanwhile, the areawide IPM
program begun by the Agricultural
Research Service in 1993 is doing its
part to help farmers meet that bold
75-percent goal.
Areawide IPM is the brainchild of
Edward F. Knipling, a retired ARS
pioneer in insect control. One of his
major achievements was develop-
ment of the sterile-male release
technique to eliminate screwworm
and other insect infestations in many
parts of the world.
Knipling realized that for most
pests, eradication is out of the
question. So in the early 1980s, he
developed the concept of using
specific insect parasites, predators,
and other tactics over a broad area to
keep pest populations below the point
where they impose a financial burden
on farmers and ranchers. Kept at low
levels, the pests would be more
responsive to biological, rather than
chemical control.

Today, the areawide concept has
grown to include not only parasites
and predators, but also other
environmentally friendly tactics, such
as mating disruption and insect
At the same time as Knipling
pressed his case in the 1980s for
areawide pest management, a series
of small-scale IPM pilot projects
produced several successful technol-
ogies, including the corn rootworm
bait featured in this issue's cover
story. Then, in 1993, ARS decided
the time was right for major areawide
IPM demonstrations.
A USDA areawide IPM working
group was formed, with representa-
tives from ARS; the Cooperative
State Research, Education, and
Extension Service; the Animal and
Plant Health Inspection Service; state
agricultural experiment stations; and
other agencies. The group discussed
the best approach for implementing
such a program and suggested several
key pests for consideration and
further review by members.
The basic idea behind areawide
IPM is to have all or most of the
farmers in a large area simultaneous-
ly implement the program, so pests
have no safe haven or alternative
food source.
ARS launched the first areawide
IPM attack against the codling moth,
a pest in apple and pear orchards, on
7,700 acres in the Pacific Northwest.
This issue's cover story describes the
program's second major assault-
against the corn rootworm-on over
40,000 acres in the Corn Belt.
If an areawide IPM program were
to be successfully launched against
corn rootworms on all of the 20
million acres of U.S. cropland
currently estimated to be treated with
corn rootworm insecticide, a substan-
tial portion of USDA's 75-percent
goal would be met by this project
alone. Fittingly, the project's fifth

year, which will be the year 2000, is
devoted to technology transfer. In
that year, USDA, state universities,
and county extension agents will be
working closely with farmers
throughout the Corn Belt, helping
them launch a broad areawide IPM
attack against the corn rootworm.
But the program isn't stopping
there. ARS is also directing new
areawide IPM projects that were
selected using a panel review
process. Included are an initiative
against a complex of insects that raid
stored grain in elevators throughout
the Midwest and one against leafy
spurge, a weed that now smothers
millions of acres of rangeland in 29
states. The leafy spurge project
includes about 46,000 acres in North
Dakota and Wyoming, with more
acreages to be added when sites are
selected in South Dakota and
An earlier project targeting the
cotton bollworm and tobacco bud-
worm has been under way on as
many as 200,000 acres near Stone-
ville, Mississippi, for the past several
years. That project predates the
official ARS areawide IPM program.
Bringing 75 percent of the nation's
farmland under integrated pest
management remains an ambitious
goal. But by implementing areawide
projects that strike pests like the corn
rootworm, codling moth, leafy
spurge, and others on an areawide
basis, the goal should become even
more within our grasp.

Robert M. Faust
National Program Leader for Field
and Horticultural Crop Entomology

Agricultural Research/October 1997

October 1997
Vol. 45, No. 10
ISSN 0002-161X

Agricultural Research is published monthly by
the Agricultural Research Service, U.S.
Department of Agriculture, Washington, DC
The Secretary of Agriculture has determined
that this periodical is necessary in the transac-
tion of public business required by law.
Dan Glickman, Secretary
U.S. Department of Agriculture
I. Miley Gonzalez, Under Secretary
Research, Education, and Economics
Edward B. Knipling, Acting Administrator
Agricultural Research Service
Sandy Miller Hays, Acting Director
Information Staff
Editor: Lloyd McLaughlin (301) 344-2514
Assoc. Editor: Linda McElreath (301) 344-2536
Art Director: William Johnson (301) 344-2561
Acting Photo Editor: Scott Bauer (301) 344-2957
Assoc. Photo Ed.: Anita Daniels (301) 344-2956
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.
Subscription requests should be placed with
New Orders, Superintendent of Documents,
P.O. Box 371954, Pittsburgh, PA 15250-7954.
See back cover for order form.
Complimentary 1-year subscriptions are
available to public libraries, schools, employees
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news media. Send requests or comments to:
Editor, Agricultural Research Magazine, Room
408, 6303 Ivy Lane, Greenbelt, MD 20770. E-
To visit Agricultural Research magazine on the
Internet, go to and select
News and Information.
This magazine may report research involving
pesticides. It does not contain recommendations
for their use, nor does it imply that uses dis-
cussed herein have been registered. All uses of
pesticides must be registered by appropriate
state and/or federal agencies before they can be
Reference to any commercial product or service
is made with the understanding that no discrimi-
nation is intended and no endorsement by the
U.S. Department of Agriculture is implied.
USDA prohibits discrimination in its programs
on the basis of race, color, national origin, sex,
religion, age, disability, political beliefs, and
marital or familial status. (Not all prohibited
bases apply to all programs.) Persons with
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(Braille, large print, audiotape, etc.) should
contact USDA's TARGET Center at (202) 720-
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write the Secretary of Agriculture, U.S.
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nity employer.

Agricultural Research

Corn Belt Growers Give Areawide IPM a Try 4

Holding Soil Fungi at Bay 8

Insect Pollinators Help Preserve Plant Treasures 10

For Pepper Growers, Built-in Nematode Resistance 12

Gin Managers Cotton To Training Classes 14

Steaming Out the Salmonella Risk 1 6

Colored Mulch Starves Nematodes 1 0

Good Nutrition Strengthens Cattle Immunity 19

Teaming With Experts To Improve Peanuts 20

New Process Keeps Biocontrols Alive Longer 22

Fungal Protein May Hold Soil Together 22

Science Update 23

Cover: Near Sheldon, Illinois, grower Joe Zumwalt applies a low-
insecticide bait that is targeted against western corn rootworms
feeding on and laying eggs in these soybeans. Photo by Ken
Hammond. (K7803-2)

Caged bees guard botanical treasures (page 10).

Agricultural Research/October 1997


a Try

Aerial spray-
ing of bait is
a big step
toward meet-
ing the
USDA goal
of using IPM
on 75 per-
cent of U.S.
cropland by
the year

Agricultural Research/October 1997

Air strikes. SLAM. What's
going on in the Corn Belt?
This past summer marked
the U.S. Department of Agriculture's
first coordinated foray against the
corn rootworm, a major insect pest of
corn, in their areawide integrated pest
management (IPM) war.
Crop dusting planes sprayed a bait
made from powdered wild buffalo
gourd root laced with a tiny dose of
carbaryl insecticide-the equivalent
of about an ounce per acre. Sold
under the trade name Sevin, carbaryl
is one of the most common insecti-
cides used by gardeners. The powder-
carbaryl mixture also has a binding
agent that makes it stick to corn
The mixture is similar to insecti-
cides that are sprayed as powders or
granules, but with one major differ-
ence: Instead of killing on contact,
the root powder-a delicacy to
rootworms-lures rootworm beetles
to eat the insecticide.
The lure of the bait seems to reside
in the cucurbitacins naturally present
in the wild buffalo gourd. Its attrac-
tion is so strong that beetles stop
dead in their tracks when they sense
it and switch from eating plant leaves
and other parts to eating mostly bait.
They eat so much of the bait that it
requires very little insecticide to do
the job.

Cucurbitacins are compounds
found in the Cucurbitaceae family of
plants that includes cucumbers,
squash, all gourd plants, water-
melons, and cantaloupe. The musky
smell released when a cantaloupe is
cut open comes primarily from

The bait is being tested at four 16-
square-mile sites and at one 8-square-
mile site. One of them straddles the
Indiana-Illinois border, while the
others are in Iowa, Kansas, South

Dakota, and Texas.
Though Texas is not
in the Corn Belt, it
is seventh in corn
production, with
crops vulnerable to
attack by both
western and Mexi-
can corn rootworms.
Actual spraying
of the new low-
insecticide bait-
sold by BASF
Corporation of
Research Triangle
Park, North Caroli- In an Iroquois
Schimmel coun
na, under the trade adults on a yell
name SLAM-will insecticide bait
occur for four a 7-day period.
seasons. The
program is being
funded for 5 years, including a year's
startup in 1996.

First Step Toward a Big Goal
"This test is part of an areawide
IPM research program to support the
department's goal of having farmers
use IPM on 75 percent of the nation's
cropland by 2000," says Robert M.
Faust of USDA's Agricultural
Research Service (ARS). "With IPM,
farmers only spray on an as-needed
basis-using professional scouts to
monitor fields and determine if pest
numbers are high enough to justify
the expense of spraying."
Faust says ARS entomologist
Gerald R. Sutter developed the
irresistible bait in 1989 at Brookings,
South Dakota.
"Larry Chandler, now head of the
ARS Crop and Entomology Research
Laboratory at Brookings, further
developed and tested the bait over the
past 3 years," says Faust. "Chandler
is co-chair of the special corn root-
worm areawide management com-
mittee, along with Richard L.
Dunkle, who is director of the ARS
Midwest Area."

County, Illinois, soybean field, scout Bob
ts the number of western corn rootworm
ow sticky trap. Application of low-
is recommended when 14 are caught over

Chandler coordinates a 16-square-
mile site in Brookings County. James
R. Coppedge, who is in the ARS
Areawide Pest Management Re-
search Unit at College Station, Texas,
coordinates an 8-square-mile site in
Bell County, Texas. The other three
sites are coordinated by state agricul-
tural experiment stations.
If the bait is judged a success after
5 years, its use could spread through-
out the Corn Belt and reduce total
corn insecticide use by half, says

TOM HLAVATY (K1289-17)

The adult stage of the western corn
rootworm (shown searching for pollen
on corn silk) is the target of ARS' first
areawide integrated pest management
program for corn.

Agricultural Research/October 1997

Faust, who is the ARS national
program leader for field and horticul-
tural crop entomology.
"Mobile pests such as corn root-
worm beetles don't respect farm
fences-let alone county or state
borders," he notes. "So IPM is most
effective when it's applied over large
That's the concept behind the
areawide IPM program: Target a key
pest over a large geographic area
with all farmers participating, so the
pest has nowhere to go to avoid
control measures. Other pests in the
area are also monitored and dealt
with using IPM strategies as needed.
Faust says this is ARS' second
areawide IPM project in partnership
with state agricultural experiment
stations and growers and is the first
to focus on corn pests.
"Corn rootworms are the target of
almost half the insecticides used in
row crops in this country, requiring
more insecticide than any other pest.
Over 20 million acres of corn are
treated each year," says Faust. "This
bait would save farmers money be-
cause corn rootworms can cost farm-
ers up to $1 billion in crop losses and
spraying expenses during a bad year.
"Of course, there will also be
environmental savings," he says.
"For one thing, the cucurbitacins in
the buffalo gourd root powder have a
bitter taste that repels most other
insects, including lady beetles,
lacewings, honey bees, and other
But Wayne Buhler, an entomolo-
gist with Purdue University in West
Lafayette, Indiana, says that the
cucurbitacins cause western corn
rootworms to feed compulsively on
the bait. And they act as a feeding
stimulant to other rootworm pests, as
well, such as the cucumber beetle.
Buhler coordinates the Indiana-
Illinois test site. He says this bait

Agricultural Research Service entomologist Larry Chandler, who is technical
coordinator of the corn rootworm areawide management program, checks a corn
ear for feeding damage.

should diminish the need for farmers
there to routinely apply a soil insecti-
cide to prevent rootworm larvae
damage to corn roots. Soil insecti-
cides are being used increasingly in
Illinois and Indiana, in response to
the western corn rootworm's recent
neutralizing of farmers' crop rotation
control strategy.
In the past, to avoid a buildup of
rootworms, some farmers planted
soybeans instead of corn in alternat-
ing years. Rootworms would not lay
eggs in soybeans, so corn planted
after soybeans would not be at risk of
rootworm damage.

Now it appears that the pests have
adapted to soybeans in some parts of
Illinois and Indiana and begun using
it for reproduction, too. By mid- to
late-July, a large number of beetles
fly from cornfields to lay their eggs
in nearby soybean fields. This
behavioral change can now result in
severe damage to corn planted after
Buhler says that annual soil
insecticide treatments have long been
the practice for farmers who grow
continuous corn, planting in the same
fields every year, and that more than
half of these treatments are probably

Agricultural Research/October 1997

Buhler anticipates that if this
areawide project succeeds, the
biggest winner will be the whole
strategy of integrated pest
"I expect this to be the greatest
boon for IPM scouting in field
crops that I've ever seen," he says.
Buhler has hired a local crop
consultant company to do the
scouting for participating farmers,
who receive a full scouting service
for weeds, diseases, and other
insect pests such as the European
corn borer. Both soybean and corn
fields will be scouted, with yield
estimates provided.

Agricultural Research/October 1997

Largely through Buhler's cajoling,
45 of 46 farmers in the Indiana-
Illinois project area agreed to partici-
pate. The 46th farmer, who farms 50
rented acres on the outskirts of the
area, was willing, but the landlord
was not.
"We're well above the 90 to 95
percent participation that's necessary
for a program like this to be sure pest
numbers are kept low," Buhler says.
The Indiana-Illinois target area
encompasses about 10,000 acres of
farmland. Another 2,000 acres
outside the edges of the target section
are left unsprayed for comparison.
"The promise," Buhler says, is that
"after several years of using areawide
IPM, the rootworm beetle population
may go so low that it will never pose
a serious economic threat-as long as
the program continues."

It Takes a Team
The Illinois-Indiana site is typical
of the five sites in terms of the broad
coalition of people needed to make
areawide IPM work: state agricultural
experiment station entomologists at
Purdue and the University of Illinois,
farmers, two pilots who spray
pesticides for a living, a fertilizer
dealer who sells SLAM, a crop
consulting firm for IPM scouting, and
the ARS National Center for Agricul-
tural Utilization Research in Peoria,
Jon Tollefson, an entomologist at
Iowa State University at Ames, is the
principal researcher for the Iowa site
and agrees, saying that his site has
similar research partners. And, he
says, ARS is the partner that provides
a large amount of financial and
technical support.
Tollefson says the key to this
program is to see if the private sector
can run it. "That's why we're work-
ing closely with private industry on
this project-so we can learn how to


Entomologist Wayne Buhler sweeps a
soybean field for western corn
rootworm adults-another way to
scout a field to determine if insecticidal
bait is needed.

transfer the technology to those
users," Tollefson says.
Roxanne Shufran, an entomologist
at Kansas State University at Man-
hattan, expects the private sector to
take over by the fifth year, assuming
the bait IPM program succeeds. "We
have hired local college-age youth as
scouts, in the hope that they will
assist in transferring the technology
in Kansas," says Shufran, who
coordinates the Kansas site.-By
Don Comis, ARS.
Robert M. Faust is with the USDA-
ARS National Program Staff, Bldg.
005, 10300 Baltimore Ave., Belts-
ville, MD 20705-2350; phone (301)
504-6918, fax (301) 504-6231, e-mail
Laurence D. Chandler is at the
USDA-ARS Northern Grain Insects
Research Laboratory, RR 3, Brook-
ings, SD 57006-9803; phone (605)
693-5239, fax (605) 693-5240, e-mail
lchandle @ ngirl.ars. usda. gov
James R. Coppedge is in the
USDA-ARS Areawide Pest Manage-
ment Research Unit, 2771 F&B Rd.,
Bldg. 2, College Station, TX 77845;
phone (409) 260-9511, fax (409) 260-
9386, e-mail *

Holding Soy Fungi at Bay

P hytophthora infestans, the
fungus infamous for causing
the Irish potato famine, has
a form called Phytophthora sojae that
attacks soybeans.
And this one is bad news, too. It
causes one of the most serious diseas-
es of soybeans in the United States-
Phytophthora root rot.
P. sojae actually attacks soybeans
at all growth stages. In seedlings, it
causes rotting of the stem, called
damping-off. Later, it causes the
stem and lower branches to turn
brown, while leaves turn yellow
and wilt. During the growing cy-
cle, it may also invade roots and
lower yields without showing any
visible aboveground symptoms.
After 30 years of investigations,
Agricultural Research Service
plant pathologist T. Scott Abney
has become an expert on combat-
ing Phytophthora, as well as an-
other soybean disease-sudden
death syndrome (SDS). Thanks to I
his research on the genetics and
virulence of fungal pathogens, the
arsenal of weapons available to
fight these enemies has increased
over the past few years.
Says Abney, "Far more diverse
fungal pathogens attack soybean seed-
lings, roots, and shoots than were
known previously. Some work togeth-
er regularly, infecting plants, reduc-
ing their growth, and lowering yields.
"Once damaged," he says, "weak-
ened plants become susceptible to
more pests."
One of Abney's tactics is to find
out how host plants and fungal para-
sites interact and how much inherent
disease resistance soybeans have for
their defense. Most have some form
of natural resistance, so yield losses
of about 25 percent-or 10 bushels
per acre-are more common than to-
tal crop failure.
Abney has focused major attention
on the Phytophthora fungus and the

soybean genes called Rps. "These
genes trigger the production of an an-
tifungal compound-phytoalexin-
that protects the plant from the fun-
gus," he says. "Once soybeans with
specific Rps genes that resist the new
Phytophthora races are identified,
public and private soybean breeders
can use them to develop commercial
soybeans with improved resistance to
Phytophthora root rot."
Since 1955 when Phytophthora
,COTT BAUER (K7692-17)

- -

[n studies to verify the more than 20 races of
Phytophthora sojae found in Indiana, ARS
plant pathologist Scott Abney (left) and Purdue
University graduate student Jose Melgar
examine thousands of fungal cultures.

root rot was first documented in the
United States, 14 resistance genes
and more than 40 races of the fungal
pathogen have been identified.
Abney's research goals with
Phytophthora are to document the
status of Phytophthora races in
soybean production areas and to
develop more effective screening
techniques to improve the efficiency
of identifying which race or races is
infecting plants.
To describe the races of Phytoph-
thora found in U.S. soils, Abney col-
lects diseased plants and soil samples
from soybean fields. Back in the lab,
he cultures the fungi isolated from
the plant and soil samples. Then he
inoculates them into soybean seed-
lings representing different Rps genes

to identify the race of P. sojae.
"Disease reactions of these soy-
bean varieties are the only way we
can identify races of the fungus and
predict what regions of the state dif-
ferent races will occur in," he says.
Abney's work on determining the
prevalence and severity of the fungus
led to his discovery and identification
of several new races of P. sojae-
suggesting that genetic diversity
among populations of this pathogen
is much greater than previously
"Phytophthora root rot is more
widespread in Indiana and other
midwestern and southern states
than expected," says Abney. In the
early 1990s, 13 of the 27 known
races were in Indiana. Abney iden-
tified seven additional races in
1993 and 1994 and is currently
confirming the existence of several
Working with Mississippi State
University scientist Kenneth W.
Roy, Abney found that Fusarium
solani and another form, F. oxy-
sporum, were the most frequently
isolated pathogens of soybean
seedlings and mature plants.
"We also found that the highly
pathogenic form A of F. solani that
causes SDS did not differ between
southern- and northern-grown soy-
beans," Abney says.
When they examined plants from
soybean fields in Arkansas, Illinois,
Indiana, Kentucky, and Mississippi to
determine the incidence and geo-
graphic distribution of F. solani in
roots of older plants, Abney and Roy
discovered that form B-differing
from form A in spore-producing
characteristics-was found most
often and was widely distributed
Additional SDS research involving
selected soybean varieties and di-
verse germplasm sources showed that
germplasm resistant to soybean cyst

Agricultural Research/October 1997

nematodes (SCN)-the P.I. 437654
extensively used in breeding pro-
grams-is super-susceptible to SDS.
"Awareness of this SDS reaction
and selection of progeny that are not
highly susceptible to SDS will permit
researchers to reduce the genetic vul-
nerability of soybeans to both SCN
and SDS," says Abney. "Knowledge
of pathogen variability and host vul-
nerability to SDS is leading to more
effective control of this new disease
of soybeans."
As a member of the ARS-Purdue
University soybean improvement
team, Abney has collaborated with
colleague James R. Wilcox, an ARS
geneticist at the West Lafayette, Indi-
ana, laboratory, to develop and re-
lease 14 soybean varieties with im-
proved disease resistance.
For all his pioneering work on
soybean diseases, Abney was recent-
ly commended by the Soybean De-
velopment Council's research com-
Charles Noble, a member of the
committee and a soybean farmer in
Daviess County, Indiana, says, "I'm
pleased with Abney's work and his
commitment to Indiana soybean
farmers. His research, which is fund-
ed in part by the council, is used by a
lot of seed companies, and that's
helping us producers get more from
our seed investment."
For his outstanding research con-
tribution to U. S. soybean producers,
Abney was awarded the production
research award by the American Soy-
bean Association in 1995.-By
Hank Becker, ARS.
T. Scott Abney is in the USDA-ARS
Crop Production and Pest Control
Research Unit, Lilly Hall of Life Sci-
ences Building, Purdue University,
West Lafayette, IN 47907; phone
(765) 494-9859, fax (765) 494-0363,
e-mail *

.\KN plant pathologist scott Abney
I left) and research assistant Tom
Richards check the grow th of soy beans
inoculated % ith field isolates of
Phylophthora sojae. Disease reactions
involving specific genes help identify.
the 45 races of P sojae that have been
reported in the United Slates.

A cultured Phytophthora sojae sample
ion while e pad) is inserted into a
natural. resistant soy bean seedling.

Agricultural Research/October 1997

4~J -I- ,.

_ 7*6


-- e
- U




Controlle Pollinaton Protecs Botanicl Diversity I

Pumpkins, corn, and certain
sunflowers all share some-
thing in common at a 120-
acre site near Ames, Iowa.
These plants at the ARS North
Central Regional Plant Introduction
Station must be hand-pollinated by
employees who are helping maintain
the genetic variability of a treasure
trove of seeds and plants gathered
from around the world.
Other plants among the 40,000
different populations, or accessions-
representing over a thousand
species-are maintained in field
cages where bees and flies cross-
pollinate them. These plants include
melons, cucumbers, carrots, chicory,
wild sunflowers, herbaceous
ornamentals, and shrubs, as well as
species of Brassica and Cuphea.
The north central location, one of
four U.S. plant introduction stations,
was founded in 1948 as a joint ven-
ture among the Agricultural Research
Service, Iowa State University, and
agricultural experiment stations of
the 12 north-central states.
"One of our chief goals is to find
ways to keep genetic variability in
the plant populations the same as
when we first acquire the acces-
sions," says the Iowa station's coor-
dinator, biologist Peter K. Bretting.

SCOTT BAUER (K7790-13)

Iowa State University plant pathologist Chi
Block (left) and ARS horticulturist Mark
Widrlechner inspect cages that keep bee po
ators inside and exclude outside sources of

A blue orchard bee pollinates a zinnia.

To achieve this, ARS scientists-
including Craig A. Abel, Richard L.
Wilson, and Mark P. Widrlechner-
combine their expertise in pollination
biology, horticulture, genetics, and
plant pathology.
Hand pollination was the normal
way to maintain the collections until
the 1970s, when honey bees were put
to use. Since then, plant germplasm
collections have grown steadily, in-
creasing the importance of insect pol-
lination and of research to make that
process work more efficiently.
Every summer, honey bees from
about 700 hives can be seen buzzing
through the mustard, zinnias, wild
sunflowers, and melons being grown
in the tentlike cages. A hive of 4,000
to 6,000 confined bees gets free lunch-
es of corn syrup when they can't be
sustained by the relatively few flowers
blooming within their cages.
In most years, too few honey bees
are available for the
pollination work that must be
done in spring. Overwintered
hives don't have enough
time to build up their
numbers before late April-
pollination time for mustard
and other plants of the
Brassica family.
Purchasing additional
honey bees from suppliers in
the southern United States is
expensive and runs a risk of
arles importing diseases and
mites. So these honey bees
llin- are being replaced by soli-
pollen. tary hornfaced bees, Osmia

cornifrons, which can efficiently pol-
linate flowers in the cool tempera-
tures of spring.
Since the early 1990s, entomolo-
gist Abel has worked on developing
rearing procedures for a native Iowa
bumblebee, Bombus bimaculatus.
These bees are now being put to work
in colonies of 30 to 150 in the field
cages. Their long tongues allow them
to pollinate flowers like snapdragons
and certain types of Cuphea that
honey bees cannot easily pollinate.
Still, honey bees in some 700
nucleus hives remain the principal
pollinating workhorses at the station
to help ensure maintenance of the
botanical treasure trove.-By Ben
Hardin, ARS.
Scientists mentioned in this story
are at the USDA-ARS North Central
Regional Plant Introduction Station,
G212 Agronomy Bldg., Iowa State
University, Ames, IA 50011; phone
(515) 294-3255, fax (515) 294-1903,
e-mail *

niu I.-II--

Technician Lisa Burke packages
Brassica seeds for distribution at the
North Central Regional Plant
Introduction Station in Ames, Iowa.

Agricultural Research/October 1997

fiA citer mnan \ear,,I of tight-
ing. the pepper \.iar
between farmers and
neniatodes continue, to
rage on. Farmers keep striking %, ith
the chemical funigant meth\ I
bromide. but the nematodes keep
comniln back. No\\ farmers face a
ban on meth\ I bromide b\ the \ear
200l. This means their main \weap-
on ma\ be taken aa\i\-and Mihal
alternauiees \\ill the\ ha\e for
continue ng thi ongoing struggle"
Fortunately\ for pepper farmer,.
the\ ha'e an unster\inlg all\ in
Richard L. Fer\. This geneticist
\ ith LSDA', Agicultural Research

ARS geneticist Richard Fery (left) and technician Floyd Maguire examine the root
system of a pepper plant showing severe galling from the southern root-knot

Whiplike larva of root-knot nematode,
Meloidogyne incognita, magnified
500X, shown here penetrating a tomato
root. Once inside, the larva establishes
a feeding site, which causes a nutrient-
robbing gall.

Service in Charleston, South Caroli-
na, has developed bell peppers that
have genetic resistance to the south-
ern root-knot nematode, Meloidogyne
Fery and his research colleagues,
who began the bell pepper project at
the agency's U.S. Vegetable Labora-
tory in 1981, have released two
resistant varieties, Charleston Belle
and Carolina Wonder.
"These are the first commercial
nematode-resistant bell peppers, and
we think they will be a big help to
growers," says Fery.
In 3 years of field and greenhouse
tests, Fery showed that both the
Charleston Belle and Carolina
Wonder are highly resistant to the

nematodes. The reason, he says, is a
single dominant gene called the N
gene, which gives the plant the
ability to ward off nematodes that
would otherwise infest the roots and
eventually weaken or kill the plant.
Considering the ban scheduled on
methyl bromide to protect the atmo-
spheric ozone layer, growers wel-
come this genetic resistance. It could
be a key component of an integrated
pest management strategy relying on
natural pest control methods to
reduce dependence on chemicals.
"Anything that is resistant to
insects would be beneficial," says
Emilo Davis of the new peppers. He
is with Gro-South of Alabama, Inc.,
in Montgomery. Though Davis does

Agricultural Research/October 1997

not have severe nematode infesta-
tions in his fields, he uses chemicals
to control other pests.
The southern root-knot nematode,
a microscopic worm that likes sandy,
well-drained soil, does its damage by
entering a plant's roots and feeding
on them. As the nematodes feed, they
start to swell, changing from eel-
shaped to pear-shaped. They remain
in the roots until they die.
Continued feeding by the nema-
todes eventually begins to reduce the
host plant's ability to take in water
and nutrients, making it more suscep-
tible to damage from heat and
nutritional deficiencies. Once the soil
has been infested with the nematodes,
it remains infested.
Injecting methyl bromide into the
soil 2 to 4 weeks before planting
seeds is the most effective way to
control nematodes, says David Nagel,
a horticulturist at Mississippi State
University. Each year, pepper crops
account for 12 percent of the methyl
bromide used in the United States for
soil fumigation.
"Without an alternative, this could
become a serious problem," says
John VanSickle, professor of Food
and Resource Economics at the
University of Florida.
In a 1995 economic study, Van-
Sickle and other researchers calcu-
lated the economic costs to the bell
pepper industry that would result
from a methyl bromide ban. Van-
Sickle's study was aimed at Florida's
winter growing season from Novem-
ber through June. It projected that in

Florida, losses in sales alone would
be $79 million. The total economic
loss would be about $127 million,
resulting in a loss of about 1,567 full-
time jobs.
The VanSickle study estimated the
loss of methyl bromide for all
farming would cost about $1.045
billion and 13,345 full-time jobs.
The new nematode-resistant
peppers could help minimize the
losses that will result from a methyl
bromide ban.
"Although the peppers and seeds
could cost more at the retail level,"
says Kenneth Jackson of the Degiorgi
Seed Company, "the benefits will
outweigh the cost."
Both Charleston Belle and Caroli-
na Wonder are dark green when
harvested, and they mature to bright-
red color. The fruits are sweet, and
they look and taste like bell peppers
currently in the market. The new
peppers, both of the species Capsi-
cum annuum, take from 63 to 70 days
to ripen.
Charleston Belle and Carolina
Wonder seeds have been offered to
about 250 wholesale and retail seed
companies for sale to the general
public beginning in 1998, says
Fery.-By Pat Sanchez, ARS.
Richard L. Fery is at the USDA-
ARS Vegetable Laboratory, 2875
Savannah Hwy., Charleston, SC
29414; phone (803) 556-0840, fax
(803) 763-7013, e-mail *


Technician Melissa Hulsey counts
southern root-knot nematode eggs
extracted from an infected pepper root.

rn P- FR 1K77-.

susceptible pepper plant roots witn
extensive galling [thickened, lumpy
portions] are heavily infested by the
southern root-knot nematode.

Agricultural Research/October 1997

See-through panels on the micro-gin allow students to observe the ginning process-all the way from crude cotton
to finished product emerging here.

Lloyd (Mike) Inlow of Hickory
Valley, Tennessee, made a
decision 5 years ago that
helped make a big difference in the
operation of Hickory Valley Cotton
Gin Company, where he is gin
manager. Inlow went to cotton
ginning school to improve his ability
and add to his already 7 years'
experience in cotton ginning.
Ginners' schools are sponsored by
the Agricultural Research Service,
National Cotton Ginners Association,
and the Cooperative Extension
System. They are thought to transfer
ginning technology at the user level
far better than any other method in
use today.
"Cotton ginners can go there to
learn the latest information on how to
preserve lint quality and increase gin

efficiency," says ARS agricultural
engineer W. Stanley Anthony, who
heads research at the Stoneville
(Mississippi) Cotton Ginning Labora-
tory. The lab's mission is to develop
new technologies and substantiate
older ones.
In terms of efficiency, Inlow says,
"We've nearly doubled our baling
capacity in the last 4 years. We've
gone from ginning 8 bales an hour to
14." He says that like students in law
school, they learn at ginning school
how to find information so they'll
know where to look when a problem
comes up.
Inlow credits technical knowledge
gained at the ginning school with
helping him make changes in the gin
operation and its machinery. "We

didn't buy new equipment but instead
modified and made adjustments to
existing machines," he says.
Stacey Harrell, a computer sys-
tems analyst for the Dumas Cotton
Gin in Dumas, Arkansas, says, "Even
though I had observed the ginning
operation while growing up and had
some experience, I really didn't know
the details until I attended the school.
I learned exactly what each machine
does and how it affects the cotton
Harrell took Level I instruction in
1996 and this summer plans to take
Level II. He hopes to be certified in
the years to come.
"I definitely think the schooling
and certification help our business.
Farmers ask questions about the

Agricultural Research/October 1997

various grades of cotton, and how I
answer them gives them a higher
confidence in our company," says
In the past, ginners had to learn by
the hard road of experience. The
school, now in its 12th year, offers a
systematic method for learning how
to improve cotton fiber. In 1992, the
school began offering optional
certification to ginners.
"Certification means competency.
And competency attracts more cotton
farmers to place their cotton in our
gin," says Bobby Greene, President
of Service in Courtland, Alabama.
Located in the northwest part of
Alabama, Servico has 30 full-time
employees. Greene says, "Two of our
employees-Kenneth Montgomery
and Willie Cross-became master
ginners in 1996. I believe that their
status as master ginners instills a
higher degree of confidence in our
Greene was so pleased with their
achievement and the improved
efficiency of his business he gave 10
percent pay raises to Montgomery
and Cross.
"Over the years, I've sent at least
10 employees to take one or more
levels of the training," says Greene.
"Every year, there's something new
to learn at the school."
These individuals aren't the only
ginners who are receiving benefits
from the intensive 3-day training
sessions held in Stoneville and at
other locations. About 3,000 ginners
representing cotton gins in 15 states
have passed through the Stoneville
gin school, according to Anthony,
who is one of the instructors and co-
developers of the curriculum at
One of the school's original
founders was Bill Mayfield. Sta-
tioned in Memphis, Tennessee, he is
the national program leader for
cotton ginning in USDA's Coopera-

tive State Research, Education, and
Extension Service. Mayfield came up
with the idea of certification and
believes that cotton gin operators,
like automobile mechanics, should
have some way of proving their
competency on the job.
The first school for cotton ginners
was held at the ARS Cotton Ginning
Research Unit in Stoneville in 1985.
Similar schools are held at the other
ARS ginning research units in
Lubbock, Texas, and Las Cruces,
New Mexico. An additional 1,700

Students scrutinize the full-sized gin
facility's work area and machinery for
safety violations and afterwards
discuss the various problems noted.

ginners have attended at those two
training sites.
And ARS researchers helped
launch the first ginning school in
Australia in 1993. Now training
sessions are run there by the Austra-
lian cotton industry every year.
Cotton ginners from 15 states have
attended at least one level or more of
training, reports Anthony.

Level I-covers proper mainte-
nance of gin equipment, air use and
drying, electrical systems, and gin
Level II-offers advanced
training in these areas and adds the
study of pneumatics, waste collec-
tion, and gin management tips.
Level III-reviews the ginning
system and provides information on
gin air systems, drying and moisture
restoration systems, bale presses,
hydraulic systems, and cottonseed
handling systems.
Special emphasis is placed on
safety in the cotton gin and common
hazards that can occur in the opera-
tion of machinery. A Red Cross
course is also part of the curriculum,
and successful completion is re-
quired for certification.
"Students have the opportunity to
meet with other ginners from other
states, and find out what problems
they have and how to solve them,"
says Anthony.
Enrollees in the school should
have at least 3 years' experience of
working in a gin. Fees of $90 to
attend Levels I and II and $120 for
Level III are charged to help offset
the school's operating costs. The
NCGA handles all monetary and
administrative matters for the
schools. Cooperators from the
ginning industry help instruct classes
at all levels.
"The Stoneville lab is unique in
that we have a mini-gin and other
machines with Plexiglas sides, so the
students can watch the cotton go in
and through the ginning process
from beginning to end," says
Anthony.-By Linda Cooke, ARS.
W. Stanley Anthony is located at
the USDA-ARS Cotton Ginning
Laboratory, P.O. Box 256, Stone-
ville, MS 38776; phone (601) 686-
3094, fax (601) 686-5483, e-mail *

Agricultural Research/October 1997

Chemical engineer Rich Radewonuk inserts a Cornish hen into an experimental chamber where a brief burst of 290F steam
will kill 99.99 percent of surface microorganisms. KEITH WELLER (K7739-11)

T he cool September breeze
ruffles the napkins on the
Labor Day picnic table that is
groaning under the weight of hot,
barbecued chicken, fresh potato salad,
and steaming baked beans.
Do the flulike symptoms of Salmo-
nella foodborne illness await these
picnic goers? Probably not.
But there would be even less chance
if a new processing technique for
poultry and raw meat designed by
Agricultural Research Service chemi-
cal engineer Arthur I. Morgan gains
widespread use.

Morgan has discovered a simple,
relatively inexpensive way to kill
Salmonella and other harmful microor-
ganisms on poultry, fresh beef, and
pork-good news for food processors
and consumers alike.
At the ARS Eastern Regional
Research Center (ERRC) in Wynd-
moor, Pennsylvania, Morgan and
colleagues have designed, built, tested,
and patented a device that kills bacte-
ria on the surface of raw meat. With-
out cooking the meat-and in just 25
milliseconds-this device kills 99.99
percent of bacteria by heating the meat

surface quickly with steam and cooling
it in a vacuum. Their prototype ma-
chine could be used easily online in
processing plants.
"Harmful microorganisms usually
dwell only on the surface of intact
meat," Morgan explains. "This is true
of enterobacteria, like Salmonella,
which originate in a living animal's
gastrointestinal tract."
This means, he says, that before
slaughter there are no toxic bacteria
under an animal's skin. However,
since the gastrointestinal tract (GI) is
removed during processing, in some

Agricultural Research/October 1997

cases bacteria may be spread from the
contents of the GI tract to the meat
Contamination may also result from
contact with workers' hands, with
slaughtering equipment, or with
chilled-water treatment baths that
carcasses are immersed in. One
contaminated bird raises the potential
of spread to other carcasses.
"Industry has a hard time removing
surface contaminants from meat
because microorganisms hang on
tenaciously. Many escape hot-water
washes or sprays containing bacteri-
cide and surfactants," says Morgan.
"This is true even when exposure
time and bactericide content are more
than enough to sterilize a smooth
surface. We've seen contaminants
remain on meat even after we've used
organic acid solutions and trisodium
One of the reasons that existing
methods aren't very effective in killing
the harmful microorganisms is be-
cause of the liquid nature of water.
"Water can't reach all the contaminat-
ed surfaces. Feather, hair, or scale
follicles are large enough to hide
bacteria, but too small to admit a
liquid wash or spray," Morgan says.
"An impossibly high water pressure
would be needed to overcome the
capillary pressure in a pore just large
enough to house a bacterium."
This makes it difficult for liquid
washes to totally eliminate contami-
nants on meat surfaces. And the meat-
packing industry is limited in using
heat because meat must keep its raw
appearance or consumers won't buy it.
Morgan came up with the idea of
surrounding the carcass with vacuum,
then applying a short burst of steam,
and finally cooling the surface with the
vacuum to kill microbes without
cooking the meat.
"We knew that bacteria can be
destroyed by disrupting their metabo-
lism, which is exactly what the steam

does," Morgan says. "Heat conduction
throughout a piece of meat is much
slower than surface heating by steam
condensation. We figured that if the
heating rates of meat and microorgan-
isms were equal, the bacteria would die
before the meat cooked. Therefore, we
knew that it's possible to surface
pasteurize meat without cooking it."

Mechanical engineers Arthur Morgan
(left) and Neil Goldberg prepare to
record data from a test run.

The equipment that Morgan uses to
prove his theory consists of an 8-inch,
stainless steel ball valve with an 8- by
11-inch treatment chamber that will
easily hold a chicken dropped in with
its legs first. Two computer-controlled
gas valves admit either steam or
vacuum into the treatment chamber.
Steam is generated in one 50-gallon
tank, and another serves as a vacuum
receiver. Both tanks are connected to
the treatment chamber by short lengths
of 3-inch tubing.
In 1 second, this machine takes the
chicken through a vacuum to withdraw

all air, flushes it with steam, treats it
with a burst of steam heated to 290F
to kill harmful bacteria, and finally
vacuum-cools it-all without cooking
the surface.
"Vacuum treatment before steam
heating removes 98 percent of the air
around the meat, and flushing with
low-temperature, no-air steam
eliminates the rest. We use low-
temperature steam in this case so the
meat won't be warmed prematurely,"
Morgan says. "Removing the air
before treating with steam actually
makes the treatment more effective,
since the air would otherwise slow
down the rate at which the steam
heats the meat surface."
"A commercial version of one of
our machines could treat 4,000 birds
an hour. This means that if we built
multiple chambers for birds, capaci-
ties would be in multiples of 4,000
for each machine," says Morgan.
"Our total cycle time indicates that
one machine can serve an entire
broiler processing line-after the
chill tank and before the clean cut-up
"We got similar results with beef
and pork. However, we think that
more pathogens can be killed on beef
and pork by using higher tempera-
tures for shorter times and still not
cook the meat.
"Future work focuses on adapting
the process to industry. This equip-
ment could be added at the slaughter-
house without increasing costs more
than a cent per pound. We're looking
for a company that might like to
license our device, which is patented
in the United States and Canada."-
By Doris Stanley, ARS.
Arthur I. Morgan is in the USDA-
ARS Engineering Science Unit,
Eastern Regional Research Center,
600 E. Mermaid Lane, Wyndmoor,
PA 19038-8551; phone 215-233-
6507, fax 215-233-6795, e-mail *

Agricultural Research/October 1997


Colored Mulch Starves Nematodes

ed plastic mulch is making
life miserable for root knot
nematodes in South Carolina
tomato fields.
In springtime field tests at Flo-
rence, tomato plants grown with red
plastic mulch
were able to RICHARD NOWITZ (K4101-11)
ward off the
nematodes and
produce more
tomatoes than
plants grown
with black
plastic mulch,
say U.S. De-
partment of
plant physiolo-
gist Michael J.
and Clemson
Bruce Fortnum.
For a decade,
and Patrick G.
Hunt of
Research Ser- Red plastic mulch c!
vice have been thus improving yield
experimenting their below-ground
with colored
mulches as a way to boost plant
yields, while conserving water and
controlling weeds. They found that
red mulch boosts yields by increasing
a tomato plant's ability to keep more
of its growth above ground,
especially in the fruit. But the latest
study is the first documenting that red
mulch also suppresses damage by
nematodes that live in the roots.
"This is especially timely because
of the impending ban on methyl
bromide, which is used to treat the
soil to kill nematodes," says Hunt. He
and Kasperbauer are based at the

agency's Coastal Plains Soil, Water,
and Plant Research Laboratory in
The scientists are not certain how
the red mulch helps tomato plants
fight off nematodes. But Kasperbauer

auses plants to put more of their energy into up
Is and, in the case of tomatoes, depriving nema

says it could be due to a tug-of-war
between the mulch and the
"The red mulch reflects wave-
lengths of light that cause the plant to
keep more growth above ground,
which results in greater yield," he
says. "Meanwhile, the plant is putting
less energy into its root system-the
very food the nematodes feed on. So
reflection from the red mulch, in
effect, tugs food away from the
nematodes that are trying to draw
nutrients from the roots," says

To test the effects of colored
mulches in small-scale field plots, the
research team sterilized the soil to
eliminate all nematodes. Then they
planted the tomatoes, mulched them
with black or red plastic, and inocu-
lated the roots with
different numbers
of nematodes-
ranging from 0 to
200,000 nematode
eggs per plant.
The results were
dramatic, especial-
ly in spring. Plants
inoculated with
200,000 nematode
eggs and grown
with black plastic
mulch produced
only 8 pounds of
tomatoes, com-
pared to 17 pounds
for the plants
grown over red
Farmers and
home gardeners
who want to take
advantage of the
red mulch can buy
per growth, it commercially.
todes of some of ARS has filed a
patent on the
mulch and is
working cooperatively with Sonoco
Products, Inc., of Hartsville, South
Carolina, to develop improved plastic
Ken-Bar, Inc., of Reading, Massa-
chusetts, sells the mulch directly and
through several supply stores and
catalogs.-By Sean Adams, ARS.
Michael J. Kasperbauer is at the
ARS Coastal Plains Soil, Water, and
Plant Research Laboratory, 2611
West Lucas St., Florence, SC 29501-
1242; phone (803) 669- 5203, fax
(803) 669-6970. *

Agricultural Research/October 1997

Good Nutrition Strengthens

Cattle Immunity

When people get the flu,
they guzzle down orange
juice. But for sick steers,
a balanced protein feed might be just
the thing.
Animal scientist Ted H. Elsasser,
who is with the ARS Growth Biology
Laboratory in Beltsville, Maryland,
has found several connections
between nutrition and how cattle
fight illness.
When germs are detected by a
steer's body, its immune system
releases cytokines, a chemical "call-
to-arms" for cells to attack the
microbial invaders. Cytokines also
trigger other cells to produce inorgan-
ic defense molecules such as nitric
But sometimes the immune system
goes into overdrive. Too many of the
cytokine messengers are released,
and the result is metabolic shock and
cardiopulmonary failure. Newborn
calves, for example, will sometimes
die when their immune systems
overrespond to ordinary barnyard
Nutrition may, however, be a tool
to modulate cytokine release.
"We did research here at Beltsville
with a group in Switzerland. We
looked at a high-protein versus a
moderate-protein diet," Elsasser says.
"We found that cytokine response to
a simulated bacterial toxin was
significantly reduced at the higher
level of protein."

But why does the immune system
overreact? Elsasser believes that the
cytokine-nitric oxide response system
may be out of sync with modern
animals' physiology.
"What's happening is the result of
lost regulatory control. You're
dealing with systems that are quite
ancient compared to where animals
have evolved," Elsasser says.
He says he looks at disease
resistance in animals as a triangle of
defense: the immune system, diges-
tive system, and endocrine system all
working together to fight infection.
Researchers at ARS' Growth
Biology lab have a special way to
make a steer's body conduct a "fire
drill" of how it responds to infectious
disease. They inject cattle with
bacterial extracts called endotoxins.
"We look at a low-level challenge
of endotoxins," says Elsasser.
"Actually, we just tickle the biology
and look for outside clues, such as
raised body temperature and appetite
In his latest research, Elsasser
found that a steer's response to
disease-and subsequent weight
loss-is more complicated than
anyone suspected.
"There are two sides to animal
nutrition; not only what the animal
eats, but what its cells can absorb and
use," he says. "The timing, patterns,
and amounts of metabolic hormones
dictate how a cell will absorb and use

nutrients. The pancreas is vital in this
process. If you compromise the out-
flow of pancreatic hormones such as
insulin, you compromise the ability
of other tissue to use nutrition."
Elsasser's first clue towards
discovering this pancreatic connec-
tion came during an experiment in
which steers became more ill during
an endotoxin challenge when they
were fed marginally nutritional diets.
Of all the organs affected, the
pancreas was more intensely affected
and for a longer time. Cells in the
pancreas were making nitric oxide-
producing enzymes at rates several
times that of healthy steers. Nitric
oxide-when too much is pro-
duced-can break down to form free
radicals that injure cell proteins.
This means veterinarians will have
to rethink the pancreas' role during
animals' illness. It also further
confirms the triangle theory of
disease response: that digestive,
immune, and endocrine systems fight
infection as a team.-By Jill Lee,
Ted H. Elsasser is with the USDA-
ARS Growth Biology Laboratory,
Bldg. 200, 10300 Baltimore Ave.,
Beltsville, MD 20705-2350; phone
(301) 504-8281, fax (301) 504-8623,
e-mail +


Teaming With Experts To Improve Peanuts

Sometimes a good idea seems to
whisper in the minds of inno-
vators, waiting to be discovered.
As a college student working sum-
mers on his father's farm, Marshall
Lamb could see that the family peanut
crop records could work harder for
them-perhaps even enhance profits.
In his agricultural economics studies,
Lamb saw how computers could or-
ganize farm data to reveal the patterns
of seemingly random numbers.
Eventually, Lamb met the Agricul-
tural Research Service scientist who
pioneered this new kind of farming
tool, and together with other re-
searchers they have expanded on this
computer-based technology, taking it
to new heights.
The technology has a name: expert
systems-which are decision-support
systems. They are a class of software
used by Fortune 500 companies and
others to pool large amounts of infor-
mation from human experts and orga-
nize it into "if-then" formulas for de-
cisionmaking. New programs on pea-
nut production make it like having a
team of plant physiologists and agro-
nomic experts assembled on your
farm for a consultation.
The challenge of creating a
decision-support system for peanut
farmers is turning records and infor-
mation into a step-by-step system that
the computer can understand. It's a
job that mechanical engineer James I.
Davidson, who is with ARS' National
Peanut Research Laboratory in
Dawson, Georgia, knows how to do.
He developed EXNUT, a program
that relies on data from the field to
improve irrigation. Growers make
measurements of soil temperature,
rainfall, and pesticide use and feed
this data into the program.
Two years ago, EXNUT shocked
veteran farmers who tested it, by
sometimes beating them on watering
predictions. When half of test fields
were watered according to EXNUT-

sometimes sooner than farmers
thought necessary-those plants
thrived while the remainder wilted.
"It costs about $4 an acre to use
EXNUT, and growers have seen it
consistently raise yields by 200 to
300 pounds per acre," says Davidson.
"We've also seen an average crop
value increase of $5 to $10 per ton,
based on grade improvements."
Crop consultant Danny Bennett, of
Bennett AgriConsulting in Cochran,

with ARS and Auburn University in
Alabama, his alma mater. His contri-
bution to this line of peanut software
is MNUT. It helps farmers make
sound marketing decisions, also
based on records they usually keep.
EXNUT and MNUT require
records on pests, minimum and maxi-
mum soil temperature, and rainfall.
After feeding the data into the com-
puter, the user tells it to run an analy-
sis. All a grower has to do then is

Left to right: Systems program analyst Jim Powell; farmer J. W. Law, Sr.; Terrell
County (Georgia) extension agent Forrest Connelly; and mechanical engineer
James Davidson discuss soil temperature, rainfall, pesticide use, and other data
being gathered from Law's peanut field.

Georgia, has 14 years of experience
and knows computers. He tested
EXNUT with several Georgia peanut
"I liked EXNUT because each
time a new producer got involved, his
knowledge and conditions, along
with industry treatments, and results
were added to the database," says
Bennett. "The potential for this pro-
gram is just phenomenal."
EXNUT was just the beginning.
Now Lamb is working cooperatively

read the recommendations that ap-
pear on screen. And to see how those
conclusions were made, the program
can be made to go back a few steps.
Mac Harrington has been raising
peanuts for 28 years, since he was 14.
He and his brother Willton grow 625
acres of cotton and 95 acres of
peanuts in Eastman, Georgia. They
decided to test MNUT as part of a
trial held by the Georgia Peanut

Agricultural Research/October 1997

"The way I look at it, MNUT helps
by giving us more market knowl-
edge," says Mac Harrington. "It
projects how our crops will do."
"Mac was one of many farmers
across the state helping validate
MNUT," says Marcus Evans, who is
with the commission. "The good thing
about these two programs is they're
self-improving. We were able to fac-
tor in new treatments such as new
pesticides and fertilizers that have a
direct impact on yields. The program
grows with the industry."
MNUT gives farmers an indication
of their crop's market value, based on
environmental conditions. It then
compares the farmer's output with
others in his immediate area, or the
state; if desired, it could give a na-
tional perspective. MNUT can help
growers and sellers predict the mar-
ket, possibly months before harvest.
"MNUT can tell the mill if a partic-
ular area's crop has been hit hard by
weather damage," says Chuck
Hancock, who is with Birdsong
Peanuts in Blakely, Georgia. "That
way, we can set quality control instru-
ments on high to get more poor-
quality peanuts out of the system."
That kind of prediction is why
MNUT is also good news for consum-
ers. It can help protect them from
aflatoxin, a potentially serious con-
taminant of peanuts that is produced
by the fungus Aspergillusflavus. Fed-
eral law prohibits selling peanuts for

Mechanical engineer James Davidson
examines a peanut plant near Dawson,
Georgia. Data gathered from field
measurements are used in developing
peanut management programs.

food unless they have less than 20
parts per billion aflatoxin. One part
per billion is equal to a drop of water
in 22,000 gallons.
For many peanut farmers, some
parts of their farm are irrigated, some
not. Rainwater is always best for the
crop, and irrigation is costly. But the
fungus loves hot, dry weather. If a
reading from MNUT predicts a high
chance of aflatoxin contamination,
growers won't mix their dryland and
irrigated peanuts, since irrigation re-
duces the chance of contamination.
"It's like if you had an apple or-
chard and got blight on one quarter of
your trees," says Harrington. "You
wouldn't mix those apples in a barrel
with the good ones from the rest of
your high-quality crop."
Better irrigation and marketing are
only part of the story. ARS agricul-

Peanut Management Programs
EXNUT, MNUT, DRYNUT, HARVPRO, and PNTPLAN will soon be available
commercially. Five other related decision-support systems are under development.
The goal is to integrate all of them into a peanut management program.




TILNUT ....................................... tillage, land preparation ......... farmer
PECMAN ..................................... curing ..................................... mill
STORNUT................................... storage ................................... mill
SHELNUT ................................... shelling, plant management...... mill
VNUT .......................................... variety evaluation ................... farmer, mill

tural engineer Jay Williams, who also
has a farm background, and Jim
Powell, a University of Georgia
systems programmer analyst who
works cooperatively with ARS, are
developing a new member of this
peanut software family called
HARVPRO. This program will help
extension agents and farmers make
better harvesting decisions.
It works like this: Growers take
peanut samples from their fields to an
extension agent who blasts off the
outer layers of the peanuts' hulls to
check the ripeness of the middle hull.
The darker the middle hull, the great-
er the peanut's maturity. The exten-
sion agent would put this maturity
profile and other data into the pro-
gram and get recommendations on an
optimal harvest time.
"One advantage of HARVPRO is,
if a grower has several fields to har-
vest, he can use the program to pin-
point fields that are ready now and
the ones that need more time," says
Williams. "It will be a good schedul-
ing tool."
All the peanut-production pro-
grams will run on computers with
MS Windows. The largest, PNT-
PLAN, is currently implemented as a
spreadsheet, but is being converted
into a stand-alone program. PNT-
PLAN is a comprehensive package
able to help with farm planning, crop
rotation, and a host of other manage-
ment decisions.-By Jill Lee, ARS.
Jim Davidson and the other re-
searchers in this article are at the
USDA-ARS National Peanut Re-
search Laboratory, 1011 Forrester
Dr., S.E., Dawson, GA 31742; phone
(912) 995-4441, fax (912) 995-7416.
For the scientists' e-mail address and
other information about these pro-
grams, visit the Dawson website at *

Agricultural Research/October 1997

New Process Keeps
Biocontrols Alive Longer

Dozens of fungi and bacteria have been tested and
found effective for controlling weeds that infest crops and
rangeland. Unfortunately, most haven't made it out of the
Often it's because the weed-killing microbes can't be
kept alive or effective for the long-term. Stabileze (pro-
nounced stable-ease), a new process invented by Agricul-
tural Research Service scientists, could change that.
"Our method uses sugar to stabilize the cell membranes
of the organisms," says Paul C. Quimby, Jr. He is a plant
physiologist at the ARS Northern Plains Agricultural Re-
search Laboratory in Sidney, Montana. "This approach
keeps a large percentage of the organisms alive for 6
weeks to 6 months at room temperature and for at least 2
years under refrigeration," he says.
Now, some organisms can only survive a few hours
without the formulation.
The sugar solution and microbes are mixed in a food
processor with silica, corn oil, and another ARS
invention-a water-absorbent starch known as Super
Slurper. The mixture forms dispersible granules that can
be applied to foliage with conventional spraying equip-
ment. Another plus: the ingredients are cheaper and easier
to work with than the sodium alginate and calcium salts
that are commonly used to make similar granules.
ARS has received patent application No. 08/695,249 on
the process. Quimby developed Stabileze with ARS plant
pathologist Anthony J. Caesar; former ARS botanist Jen-
nifer L. Birdsall, who now works for USDA's Forest Ser-
vice; ARS chemist William J. Connick, Jr.; ARS plant pa-
thologists Clyde D. Boyette and Nina K. Zidack; and
plant pathologist William E. Grey, who is at Montana
State University in Bozeman.
Ideally, commercial manufacturers and users would
like a 2-year survival rate at room temperature, to save on
refrigeration costs. But Stabileze is a step in the right di-
rection.-By Kathryn Barry Stelljes, ARS.
Paul C. Quimby, Jr., Anthony J. Caesar, and Nina K.
Zidack are at the USDA-ARS Northern Plains Agricultur-
al Research Laboratory, P.O. Box 1109, Sidney, MT
59270; phone (406) 482-2020, fax (406) 482-5038, e-mail
[Quimby] [Caesar]
caesara @sidney.ars.
William J. Connick, Jr.,is in the USDA-ARS Commodi-
ty Utilization Research Unit, P.O. Box 19687, New Or-
leans, LA 70179; phone (504) 286-4511, fax (504) 286-
4367, e-mail
Clyde D. Boyette is at the USDA-ARS Southern Weed
Science Laboratory, P.O. Box 350, Stoneville, MS 38776;
phone (601) 686-5222, fax (601) 686-5422, e-mail *

Glomalin-Soil's Superglue

Agricultural Research Service soil scientist Sara E.
Wright has discovered a unique fungal protein that may
be the primary glue that holds soils together.
She named the gooey protein "glomalin" for Glomales,
the scientific name for the group of common root-
dwelling fungi that secrete the protein through hairlike
filaments called hyphae. The fungal hyphae are found
worldwide on the roots of many plants. Glomalin sloughs
off of the hyphae and finds its way into soil.
"It coats soil particles and may be what holds them
together in the stable structures we call aggregates," says
Wright. "Farmers and gardeners know them as the small
grains of soil that sift through their hands and suggest to
them that the soil has good structure."
Wright knew she had something unique when it took
up to 90 minutes in a heat-sterilizing autoclave to free
glomalin from the hyphae. "That's unheard of in the soil
sciences, although an hour or more of autoclaving has
been used to free proteins from some yeasts. With that
level of persistence, we knew glomalin must stay in the
soil, too."
So Wright began searching soils. She started with a
dozen eastern soils and found that with the measuring
technique she used, glomalin was as high as 2 percent of
the total weight of a soil aggregate. When she moved on
to test soils from the West and Midwest, she found levels
were dramatically lower, although still abundant. She has
also found glomalin in soil samples sent from several
cooperators throughout the world.
"It may be that the higher glomalin levels explain why
eastern soils have stronger structural stability than west-
ern soils," says Wright. "Knowing about glomalin gives
us a reason to alter farming practices to raise or maintain
glomalin levels. For example, tillage tends to lower
glomalin levels. We found that soil from no-till corn plots
had more glomalin and higher aggregate stability than soil
from tilled plots."-By Don Comis, ARS.
Sara E. Wright is at the USDA-ARS Soil Microbial
Systems Laboratory, Bldg. 001, 10300 Baltimore Ave.,
Beltsville, MD 20705-2350; phone (301) 504-8156, fax
(301) 504-8370, e-mail *

Agricultural Research/October 1997

Cook-and-Serve Meals for Bugs
Liver and ground beef are twvo
ingredients in the recipe of a new lab
diet for mass-rearing pest-eating
insects. ARS scientists are patenting
the diet. It can be used to rear about a
dozen different insects. These include
Diapetimorpha introila parasitic
w asps and a predator called the
spined soldier bug. ARS scientists
developed and tested the diet under a
cooperate e research and develop-
inent agreement (CRADA) with
Predation. Inc.. of Alachua, Florida.
The scientists are refining the diet.
For example, they want soldier bugs
raised on the diet to produce more
eggs than they do v\ ith the diet's
current formulation. Under a differ-
ent CRADA. the scientists are


The parasitic wasp, Diapetimorpha
introita, is a biocontrol for fall and beet

working with another firm to come
up with diet "serving trays." The
ARS scientists and Analytical
Research Systems, Inc., in Micanopy,
Florida, are testing various types of
polymer film coatings. The coatings
will contain and store thousands of
individual servings of the diet. One
requirement: Insects must be able to
open the containers themselves to get

their meals. Patrick D. Greany,
Center for Medical, Agricultural. and
Veterinary Entomology, Gainesville,
Florida; phone (352) 374-5763, falx
(352) 374-5923. e-mail
pgreany @ nervm,.nerdc.

Hormone Could Make Suckers the
Baitfish of Choice
An experimental hormone could
make two baitfish species-white
suckers and spotted suckers-more
popular with aquaculturists. Today.
7-inch-long golden shiners are the
staple baitfish for very large sport-
fish. But they take 2 years to grow to
maturity. ARS scientists say white or
spotted suckers will reach maturity\ in
1 year. Speedier production could
translate into higher profits for
producers. The problem is, sucker
fish prefer laying eggs in rivers and
other running waters. But the scien-
tists found that giving the fish a dose
of a s) nthetic form of a hormone,
human chorionic gonadatropin
(HCG), encourages them to spawn-
regardless of the setting. That could
open the way to pond production.
White suckers grow best in cool
waters north of Arkansas. They're
good bait for striped bass, muskies,
black bass, and other large game fish.
But white suckers cannot be intro-
duced into states such as Florida,
where they are not considered a
native. Spotted suckers, a second
option, are native to Florida and
some other southern states east of the
Rocky Mountains. HCG is syntheti-
cally produced for medical uses. The
U.S. Food and Drug Administration
has approved its use in fish only for
experimental purposes. FDA would
require further studies before consid-
ering its approval for use on food or
brood fish. Gerald M. Ludwig,
USDA-ARS National Aquaculture
Research Center, Stuttgart, Arkan-
sas; phone (870) 673-4483, fax (870)

New Sensor Is Anti-Smear
Campaign for Soil
When planting equipment sows
crop seeds such as corn. it rubs
against the soil. The rubbing may
smear the soil-forming a smooth.
dense la)er in the furrow. The slick
layer slow\ s air and water flow
through the soil and restricts shoot
and root growth. More pressure from
the planter can mean more smearing.
There's no effective %way to detect
how much soil smearing a planter
causes, so it's difficult to estimate
crop losses. But ARS scientists are
developing a fiber optic sensor that
could alert farmers to smearing in
progress. The grower can then adjust
equipment or change planting attach-
ments. The research is part of the
emerging high-tech field of precision
agriculture, using new technology to
help farmers conserve resources
while improving their production
efficiency. The sensor projects a light
beam onto the side of the seed furrow
and analyzes reflected light for
characteristics that indicate smearing.
ARS scientists are looking for
partners to develop the sensor
technology for the marketplace.
Donald C. Erbach, USDA-ARS
National Soil Dynamics Laboratory,
Auburn, Alabama; phone (334) 844-
4741, fax (334) 887-8597, e-mail

Agricultural Research/October 1997

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( FarmWin 97, a new whole-
farm recordkeeping software
package available this year,
helps producers plan every
aspect of farm management.

( Mike Baker, manager of
North Carolina Foundation Seed
Producers, often has tofu on his
mind these days. But his hunger
is for finding opportunities to
help small-scale soybean
farmers in North Carolina.

- ARS horticulturist James B.
Magee and Mississippi State
nutritionist Betty J. Ector predict
that muscadine grapes will not
only be an alternative crop for
growers in the southeastern
United States, but a new health
food as well.

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