K
''*
.r44
i .
y 
.
t. 
g@p
b 9PPi
S
Yti 
. ...
In this issue
r
T$lb~
Z;" i
E
r
re IL
AAES Research Developing Simple.
Inexpensive Tests for Meat Products
ON THE (OVER: AAES tests show ti
Marshall annual ryegrass produces more a
meal weight than Gulf. See related story
page 12.
ILupin Silage-An Alternative Forage
Moving Air Repels Cockroaches
('an Tasty Lettuce Be Grown in
\labama?
Weeds in Peanuts?
Why Not Just Mow Them Off?
Novel Chemicals Control
Bacterial Spot and May Reduce
Copper Contamination Problems
Marshall Ryegrass Dramatically
Superior Under Grazing
Research Leads to Specific
Identification of Human and
Veterinary Pathogens
Potassium Fertilizer Placement Effects
on Uptake and Root Length Density
of Cotton: Three Year Summary
Okra Leaf Cotton Tested for Use in
Alabama's Gulf Coast Region
S LI Il l n e r 1 9 97 V o I u m e
4 4 N ui m b e r
A Q2t \ilri'i Ri imi i Ri 'I i_ izi Pt iii 1,11 i its Ai us Isi \ Aaii Ii Rvi I Nit iIF~ Ni Siiy AiR \i iv, RN~y tii <,11
JAMES F. MARION ........... Director EDITORIAL COMMITTEE: Art Chappelka
Associate Professor of Forestry. Robert
JTAMES R. ROBIRSON .......... Editor Nelson. Associaie Professor of Agricultuial
Economics and Rural Sociology: Art Avery.
('A1 ERlNF. L. SMITH .. Associate Fditor Professor. School of1 Human Sciences: 
David
Strinetelloss Associate Professor of Animal
Health Research. Beth Guertal. Assistant
R11RI1 A. lit ARN . . .Associate Edior
Professor of Agronomy and Soils; Geoffrey
lehnder Associate Professor of Entomology;
l'l'Rt'SA F. RODRIGUEZ ... Art 
Designer and Roy Roberson.
dior's Note. Mention of IIade inmes does not
Indicate endorsmen i y he Alhaa Agricultiural
Experimeni Station or Auburn University ot one
hrand over anothe Any use of pesiicide rates in
exccss of I.ibeled amano s in reseairc h repoited
does not costitute recimiidctdioun of such iaie.
Such use is sitmply part of lie scteiiitic invcsiga-
tion necessaiy to esaluate vatious imtariaii.ls No
chemical should be used at rates ahove those per-
miiied by the label. Inforinaion coitained here
in is asailable to all persons without retard to i ace.
color sex, or national origin.
Alabamaoa Agrichultra/l E \i'imlicit Station
Highlights of'Agriculruoal ReseacNh Vol. 44, No. 2, S'mm,,oer I997
'
PARTNERSHIPS...
The last issue of Highlights was the Annual
Report for the Alabama Agricultural Experiment
3 Station. That report documents a partnership that AAES
has with Auburn University to carry out research to sup-
4 porters 
of agriculture, 
forestry. and 
related agribusiness
in Alabama. It also emphasizes the federal and state
partnership that supports AAES iesearch.
6 Another important partner with AAES is the
user of our information, the agricultural producer. In
this case, the "user" benefits from our work, but at the
8 same time, 
our project leaders 
benefit directly 
and
immeasurably froi the feedback and financial support
that comes from these clientele who use AAES-gener
ated research data. This is a "partnership" that is alive.
10 well and working mutually for everyone involved.
In our annual report, we listed all research pro-
jects supported by state and federal tax dollars. Since
12 some of these projects are also supported by gift. grant,
and contract funds, I plan to also list some of special
research areas supported by these outside dollars. At
this time, we acknowledge proudly that producers
15 through the following organizations provide well over
$500,000 directly for agricultural research at AU:
Alabama Catfish Producers
Alabama Cattlemen's Association
16 Alabama Cotton Commission
Alabama Peanut Producers Association
Alabama Soybean Producers
18 Alabama Wheat and Feed Grain Committee
Cotton. Inc.
There are many others who partner with
19 AAES, but this is a list of our closest partners who
determine each year how much to set aside from their
hat dollars for programs 
at AU. Our thanks 
to these part-
mni ners at this 
time. We plan to 
publish a project 
list soon
on and will 
include a list 
of many others 
who support 
ag
research at AU.
Jal.v E.l Marion,
iI)
idU~uiri Si la ecV
An Alternative Forage
Sura sak Kochapakcee, Pete Moss, J.L. Lin,
Wa ne Ree ves, anl Paul Mask
Mw. ;labama's growing 
season is ideally suited to
double cropping, but corn silage, a major for-
Otte for dairy diets, needs to be planted earlier
E l than the date which many winter crops are har-
IVA { v -ited. However, 
whole plant lupin, a winter 
legume, can be
removed sufficiently early 
as silage to allow most summer 
crops
to be planted. Research at AAES indicates that lupin silage can be
d i1 \ ~used in place of corn silage in dairy diets without depressing milk yield
And composition if diets are adequately balanced.
A typical double cropping
system in Alabama often involves a
cool season small grain such as wheat
and warm season annual such as soy-
bean that can be planted in June.
Winter crops unduly delay planting
corn and preclude temperate corn
being double cropped. Therefore,
some unconventional crops such as
tropical corn and hybrid pearl millet
may be more desirable because they
can be planted later than temperate
corn. Lupin, another unconventional
crop, is a winter legume which may
have agronomic advantages. Ensiling
such crops may provide better double
cropping options as ensiling removes
crops earlier than if used for grain
production. However, the economic
values of such silage will depend upon
their use in livestock rations. A study
was conducted to compare the lactation
responses of dairy cosy s recei\ing
these unconven-
tional silage-based
diets to those fcd
conventional ten
perate corn silagc-
based diets. 'This
was one aspect of
a larger douhle
cropping system
approach which
involved AAES
departments and the
Effect
A lactation study was subsequently
conducted at the .V. Smith Research
('cute! tiom Jiua LKI_ to \pt il 1990.
of Silage on Dairy Cow Performances)
Silage-based diet DMI MY BF MP BUN
Ib.lday Ib.lday pct pct. mgldl
Temperate corn 49.9a 67.8a 3.5a 2.9ab 19.7ab
Tropical corn 43.6b 59.Ob 3.8b 3.Ob 18.6a
Millet 37.8b 57.9b 3.7ab 2.8a 21.1 b
Lupin 43.1 b 62.7ab 3.6ab 2.9ab 18.4a
'DM1 = dry matter intake, MY = milk yield, BF = butterfat, MP =
milk protein, BUN = blood urea nitrogen.
Means within column with different superscripts differ (P < 0.05).
L SDA-ARS.
Approximately 55 tons each
of corn, tropical corn, millet and lupin
were ensiled into polyethylene bags
during May-August 1995 at optimum
maturity stages for the different crops.
Ien lactating Holstem ns were assigned
to each of six (three temperate corn
and one each of tropical 
corn, millet,
and lupin) silage-based diets. Cows
Lupin Silage, continued on page 4
Alabama Ai~riculutral Hperitnent Station
HIlightllst ofAgricultural Research Vol. 44, No. 2, Sumner 1997
were maintained in tic stalls and individually fed
diets free choice.
The compositions of temperate corn, trop-
ical corn, pearl millet and lupin silage used in the
diets were: dry matter (%) 41.4, 30, 30.4, 26; pro-
tein ('%) 7.1, 8.8, 1 1.9, 13.9; soluble protein (C% of
total protein) 44.2, 41.9, 57.4, 55.2; acid detergent
fiber (%) 21.3, 31.5, 29.9, 40.7; neutral detergent
fiber (%) 41.1, 56.6, 52, 54.6; and net energy for
lactation (NEL) (Mcal per pound) 0.70, 0.60, 0.63,
0.52. Diets were formulated to meet requirements
for 75 pounds of milk yield per day and contained
similar silage content. Other ingredients were var-
ied to obtain an equal amount of protein (15.5 
(%),
NEL (0.73 Meal per pound), and mineral content.
Milk, milk composition, feed intake, body weight
and blood samples were collected for I I weeks.
Weight gains of cows in this study were
similar across diets (0.41 - 0.63 pounds per day).
Cows fed the temperate corn silage diets consumed
more feed than those fed tropical corn, millet, or
lupin silage (see table). Although cows on the trop-
ical corn silage or millet silage diet gave less milk,
those on the lupin silage diet produced similar milk
compared to that from temperate corn diets. Milk
fat and milk protein were similar for all treatments.
Blood urea nitrogen from cows fed millet silage
was higher than that on other diets. Since blood
urea nitrogen is considered to be an indicator of
protein status, this may reflect poor protein utiliza-
tion of millet silage. However, this did not affect
milk protein content. Data on digestibility and uti-
lization of these diets are being analyzed and the
results will explain the differences on lactation per-
formances among different diets.
Results from this study suggest that lupin
silage may be used in dairy diets based on similar
milk production and milk composition to that from
conventional temperate corn silage-based diets.
Further evaluation is needed to determine the
economic value of production per acre when the
entire double-cropping system is utilized.
Research is also being conducted at AAES to
develop improved varieties of disease-resistant
lupin for the Southeast.
Kochapakdee is a Graduate Student, Moss is a Professor,
and Lin is a Research Associate of Animal and Dairy
Sciences; Reeves is an Adjunct Associate Professor USDA-
ARS National Soil Dynamics Laboratory; and Mask is a
Professor of Agronomy and Soils.
Mouing Air Repel4
People don't like air blowing in their face, and
neither do cockroaches!
Research by the Alabama Agricultural
Experiment Station has shown that all stages of the
German cockroach, the most common insect pest of
home and commercial kitchens, can be repelled with
moving air.
German cockroaches are important pests
because they infest food and contaminate it with saliva
and fecal material. Cockroaches can also transmit sev-
eral pathogens and parasites, and their body parts and
feces are potent human allergens.
A variety of tactics such as insecticidal baits,
sprays, and dusts are used to control German cock-
roach infestations. Repeated use of the same insecti-
cide often results in resistance making it more difficult
to control these pests with insecticides. There are few
non-insecticidal tactics available for development of
integrated pest management (IPM) programs for cock-
roaches. Development of a nontoxic method to repel
cockroaches could aid control by forcing cockroaches
out of preferred and difficult to treat areas.
Moving air has been utilized to exclude house
flies from the entrances of food-processing and storage
facilities (air curtains). Utilizing moving air to aug-
ment German cockroach control could reduce the
amount of insecticide applied by moving cockroaches
out of hiding places and onto insecticide deposits.
To test the repellency of moving air, an elec-
tric version of the classic Ebeling choice box was
developed (Figure 1). The electric choice box consist-
ed of two parallel plastic pipes with an access hole
between them. One pipe was painted black and equipped
with a fan and restrictor plate to adjust air flow between
0 and 4.75 meters per second. Household forced air
conditioning and heating systems produce air veloci-
ties of 4-5 meters per second at the vent register.
Alabama Agricultural Experiment Station
Highlights of Agricultural Research Vol. 44, No. 2, Sunmmer 1997
Artt Appcl, I)onnii x Osivall
Lane Smith, andl Joe Kool
Therefore the range of air velocities
tested are quite relevant to air flows
found in typical Alabama homes. The
other pipe was clear and supplied with
a piece of dry dog food and a cotton
water wxick.
Cockroaches could choose to
enter the dark pipe (where they would
normally hide) and be exposed to an
air Ilow or remain in the light and in
still air. Repellency in this study was
therefore relative to that of light.
Adult or iimature cockroach-
es were placed into the electric choice
boxes and allosed to select the dark
(with moving air) or light side. Choice
boxes were run for liv e days in a room
where lights were turned on for 12
houirs per day. The position (light or
dark side) and condition (living or
dead) of each cockroach in each box
was recorded approximately 10 am.
each morning (flour hours after the
lights were turned on).
All stages of the German
cockroach were repelled by flowing
air. Repellency increased with increas-
ing air velocity between one and about
3.75 meters per second. reaching almost
901% at 3.75 meters per second (Figure
2). Air velocities below one meters per
sec were not detected by most stages:
and velocities above 3.75 meters per
second did not increase repellency
because the cockroaches could not dis-
criminate greater velocities.
In tests xith simulated kitchen
cabinets, cock- Repellency, %
roaches scic 100
SAdult males
moved fron thci Gravid Fen
80 Nongravid
preferred restilll 
8 Large 
nYm
places at the top Small/med
of the cabinet to 60
the bottom of the
cabinet (Figure 3) 40
in response to
moving air. II 20
cockroach popu
lations can be 0
ioved out of 0 1
preferred resting,
areas, they might be diricted to inscc-
ticidal baits placed on the bottolm of
cabinets and beneath stoves and
refrigerators. In addition, air flow
could prevent infestations by
repelling cockroaches from sheltered
locations to areas that could not sLp-
port population growth. In conclu
sion. strategic redirection of air llosx
into potential cockroach restin-e
places could provide another lox\
toxicity tool for control of- German
cockroaches.
Appe is ar Associate Professor. Oswat
a Former Graduate Student, ard Smith
Post-Doctoral Fellow of Entomology; arc
Koon s an Associate Professor of
Agricultural Engineering.
2 3 4 5
Air velocity
roti Ii.5 r//N p/hd al raio.s air ilocilt
Figir'e 3, heon. Relale cR/anige ih n o. ori o/
G;erlali loci/hs eirp 1sed to 4.75 hlcrpe,
seiolu/ air i eloiir in a simiii/ated k.i/chen catbjinet.
60
-v r 40
v0 20
ro 
0
00
c
> -20
EO -40
v c
' -60
-80
o -100
U
MStill air
0 Air flow
Middle
of Cabinet
Bottom
luh/at/n/ Ag1icu lii 1/l E /c leimeti'h1/ Station
H~igh~lights oA icultura/ Resrearch Vol. 44, No. 2, Sunnter /997
nales
Females
phs .
ium nymphs
CIhN TAVTY IPTTIfF 
E I 4OWNY IN AIIRAM
7
Amy Simonne, Eric Simonne, John Owen, Larry Wells, and Ron Eitenmiller
IT IS OFTEN SAID that lettu
Alabama is too bitter because of the we
red lettuce is more bitter than green. An
assessing bitterness by sensory evaluati
types of lettuce revealed that acceptabl
good tasting lettuce can be grown in Alaf
C 4F~-
/L 'I;
to w.
.
tea. ."
ice grown in
Presently.
ather, and that commercial production
AAES study of lettuce in the 
United
on in various States exceeds 205,(XX)
quality and 
tons annually, 
and is
mainly located in
ama. 
California. 
Although
lettuce is a popular crop
n home c 1adens, no commercial produc-
tion of lettuce in Alabama exists. Main
tvpes of lettuce commercially available
,ire (1) crisphead (iceberg) [head let
tucel, (2) Romaine, (3) butterhead, and
(4) leaf lettuce. Most people are familiar
with iceberg lettuce because it is com-
monly sold in stores, but leaf lettuce is
commonly grown by many home gar-
deners. In addition to variation in head
\hapes, lettuce with different foliage col-
o~rs from traditional greens also are avail-
aible.
Because the harvestable part of
lettuce is a rosette of leaves, any foliar
damage caused by insects, viruses, or
Cungi reduces marketability. The main
Objective of lettuce breeding programs is
to produce lettuce resistant to several
iruses and diseases. Resistant genes
Irom wild Lactuca species are often
,iced as sources of resistance to viruses
anad other diseases. However, incorporat-
ing resistant genes from L. saligna or L.
virosa often lead to increased levels of
sesquiterpene lactones which are the bit-
ter compounds of the latex of the wild
lettuce . Over 5(X) types of sesquiterpene
lactones are present in Compositae
plants. Little information exists on the
relationship between bitterness and the
"csquiterpene lactones levels and the let-
tuce acceptability.
Commercially available
lettuce varieties (Table I) were
grown at the Wiregrass and Piedmont
Substations following current fertiliza-
tion and pest control recommenda-
tions. At maturity, lettuce was hand
harvested, washed and cut into bite-
size pieces similar to those found in
tossed salads. Lettuce samples were
served one by one to a group of 15
trained panelists. Panelists were
trained prior to the tasting session. The
training session consisted of providing
each panelist with a series of caffeine
solutions with increasing bitterness
and their corresponding bitterness rat-
ing (0% = 0, (.05% = 2, 0.08%; = 5,
0.15% = 10 and 0.20% = 15). Hence.
when the trained panelists 
were used,
it was possible to quantify panelist
response in numeric scores. Panelists
were instructed to calibrate their taste
using the caffeine solutions between
each sample.
Mean, most frequent, lowest
and highest scores for each lettuce
variety and growing locations are pre-
sented in Table 2. Scores varied con-
siderably between panelists. Although
significant differences between vari-
eties were found. 28% (five out of 18)
of the entries were given the highest
score of seven or less. Most prevalent
scores were less than four, suggesting
that the lettuce was not bitter or was
very little bitter. Although, depending
on the individual, bitterness scores of
less than seven would be considered
acceptable as commented by trained
panelists. Panelists did not reject red or
purple lettuce. Growing conditions
Alabama A gricultural Experinent Station
Highlights of'Agricultural Research Vol. 44, No. 2, Summer /997
r h
seemecd to atffect hi tiCiness nCsr. This culturial pi actic" and harv est dates on
study suggests that it is possible to sensory attributes of lettuce.
grow non-bitter, pleasant tasting 
let- A. Simonne is a Post Doctoral 
Fellow in the
tuce in Alabama. Future studies will Depai 
rment o f Nutr io rn riFoo d Science;
Incus tin deterioning the impact of 1. Simor'e i nA,,sita Processr inthe
Table 1. Seed Source, Head Types and Disease
Claims of Selected Lettuce Varieties
Variety Seed source
Big Curly Vilmorin
Brunia Vilmorin
Cabernet Red Asgrow
Epic Sakata
Greengo Asgrow
Legacy Takii
Nancy SeedWay
Nevada Vilmorin
Optima Vilmorin
Parris Island Stokes
Redprize Ferry-Morse
Red Salad Bowl Vilmorin
Salinas 88 Supreme Sakata
Sierra Vilmorin
Slobolt M.I. Harris Seeds
Prote soir ich Depairment of Lood
Science and Technology, University of
Georgia, Owen is Superintendent of the
Piedmont Suhstation; and Wells is
Superintendent of the Wiregrass Substation.
Head type Leaf color Disease claims
Marai chere
Oakleaf
Looseleaf
Crisphead
Looseleaf
Crisphead
Butterhead
Batavia
Butterhead
Romaine
Looseleaf
Oakleaf
Crisphead
Batavia
Looseleaf'Frisee'
Green
Green/Red
Red
Green
Green
Green
Green
Green
Green
Green
Green/Red
Red
Green
Green/Red
Green
DM,LMV,IB
DM,LMV
TB
TB
LMV
DM,TB,LMV
LMV = Lettuce Mosaic Virus;TB = Tip Burn; DM =Downy Mildew.
STable 2. Sensory Evaluation of Bitterness in Lettuce Varieties t: Bitterness Score
'ariety
:Pic
alinas
'Jevada
'ed Prize
egacy
erra
fJancy
ted Salad Bowl
Wrunia
:abernet Red'arris Island
lobolt M.
optima;reengo
fJancy
Sig Curly
lobolt M.
Type Location
2
Mean score tnt
Head
Head
Batavia
Leaf
Head
Batavia
Butterhead
Oak leaf
Oak leaf
Leaf
Romaine
Leaf
Butterhead
Butterhead
Leaf
Butterhead
Marai che re
Leaf
WS
WS
PS
WS
WS
PS
WS
WS
PS
WS
WS
WS
WS
PS
WS
PS
PS
PS
1.6 (14)
1. 6(14)
2.0 (16)
2.2 (14)
2.3 (14)
2.5(16)
2.9 (14)
3.2 (14)
3.3 (16)
3.5 (14)
3.6 (14)
3.8 (14)
4.1 (14)
4.9 (16)
5.2 (14)
8.4 (16)
9.3 (16)
10.1 (16)
1For more details of yield performance of these lettuce varieties,
2 PS =Piedmount Substation;WS 
=Wiregrass Substation
3Highest scores reflect highest levels of bitterness in taste panel
Most frequent Lowest Highest
3
10 6
0 o 4
0 o 9
2 0 7
10 7
2 0 7
3 0 10
0 0 11
1 0 10
2 1 13
3 0 14
2 0 10
2 0 12
0 0 13
5 1 IS
4 0 I5
13 0 IS
IS 1 IS
see 1996 Spring Variety Trial Report.
evaluation.
lIu/k11u \ 1 I lla IiU//f t! / /U imr1i Jhl ioul~
High/lig'hts o/ Ag'riceultrul Remwon/i Vol. 44-, No. 2, Snumer 1997
YYEEDS IN PEANUTS/
WHY NOT JUST MOW THEM OFF?
Glenn VWehtje, Larryv Wells, Rob Martin, and Ron Week.s
poradic clumps of weeds waving above
the peanut canopy is a common late-
season sight in peanut country. These
weeds probably represent a small percent
age of the total weed population that
somehow managed to escape the weed
control program that was used by the
grower. Yet, these escapes are easily noticed and
often reflect negatively on a grower's ability to
control weeds. So why not just mow the weeds and
avoid the use of herbicides?
~Z s '* ~
Eirst, much of the competitive
ability of weeds is already inflicted on
the crop by the time weeds extend
above the peanut canopy. Mowing is
simply too little too 
late. Secondly,
weed foliage that is thrown onto the
peanut canopy during mowing can
serve to retain disease-promoting
moisture within the canopy.
But in all honesty mowing
may have some validity. Mowing is
cheap and non-herbicidal, which is a
benefit in the opinion of some. And
mowing is being used by some grow-
ers. In addition, data to back up the
case against mowing does not exist. A
review of the literatire over the past
decades recovered no studies in which
mowing was honestly evaluated and
compared to herbicides. 
In contrast,
several studies were found (circa
192()-30) in which mowing was rec-
ommended as a method for controlling
weeds in small grains. Apparently,
what support mowing may have had
in the past dwindled as herbicides
became available from the 1 950s.
A recent AAES test evaluated
this mowing question. Fxperinents
were established at th,
Wiregrass Substatioi
Treatments consisted Tab
for whic
weed control inputs (i.
commonly used herhb
cides and/or cultivatioin 
Herbicide!
that ranged progressivcil, cultivation
downward from acL system
quate (System I) to nonc
(System 5). These treat
ments 
were then 
supple- 
2
mented with either none.
one, two, or three mow- 3
ings. If 
mowing 
was ben, 
4
icial, it should 
make tI 
5 ye
performance of the 
subail Typical 
apl
equate treatments equ :! follows; parac
to that of the more adl surfactant (X
2 '+' 
indica
quate systems. Mowing was pre-
formed with a 'Bush-hog' type mower,
and was done whenever weeds extended
above the peanut canopy by about six
inches. Data collected included visual
le I. Herbicide and Cultivation Systems
h Mowing was Evaluated as a Supplemental
Weed Control Input; 1993-95
Degree Her bicide applications'
of inputs Ist application 
2nd application Cultivatic
(within 2 wks (row closure)
of emergence
adequate Stairfire+
2,4-DB
marginally Starfire+
adequate 2,4-DB
subadequate Starfire+
2,4-DB
subadequate none
Classic
+2,4-DB
Classic
None
none
once
once
once
twice
ry subadequate none none none
plications rates were observed for all herbicides, and were
quat, I I oz/a; 2,4-DB I pc/a, and classic 0.5 oz/a. A nonior
77) was included in all herbicide applications at 0.25% v/v.
ates tank mixture.
Al hooou A> ;, o oluo ul 1 \/)cr (in j (I oNIiii
Hil,'hlig'hts of Ag(ri(IfltIJl Recarchz Vol. 44, No. 2, Stemner 1997
3
kt'~l
55ee ecotrtol at the end ot, the \eason.
disaIse occurrence and yield. Net
returns were calculated from the yield
data.
Without any mowing, System
I (adequate) was the most effective.
Control of bristly starbur
sicklepod and Florida
beggarweed was at least
80%4 (data not shown).
With this system mow-
ing offered no improve-
ment in control over
\\ hat was obtained by
the herbicides and
cultivation alone.
SMowing 
tended 
to
improve weed control in
the remaining systems.
- . Generally a single mow-
,,: in( was nearly as effec-
tive as either two or tlee
mnwings.
Defoliation due
to loliar diseases tended to reflect the
amount of weed control inputs.
Minimum defoliation (3 I K%) occunred in
System I (adequate weed control inputs.
data not show)ii. (omci Nels, Inr~tinnliiii
deftoliation 139 ( ) occurred in Sx stema 5
(no inputs). Thi s probably can be attrih-
uted to uncontrolled weeds interferine
with fungicide application. With System
5 in 1994 and 1995, and System 4 in
1994 mowing reduced defoliation. No
treatment-indiced differences were
detected in the occurrence of southern
stem rot (otten called white mold) in
1995. Southern stem rot was much more
rIev alent in 1994 than in 1995: and
mowing generally increased its inci-
dence.
Yield and net return results
from 1993 were different than that
obtained in 1994 and 1995. Rainfall dur-
ing the 1993 growing season (April
through August) was 17c less than the
long term average. Conversely, rainfall
in 1994 and 1995 exceeded the long
term average by at least 301%.
In 1993. iaxiiuii yield and
net return without mowing was obtained
with System 1 (3,895 pounds pet acre
and $9X per acre). Yields of Systems 2-5
generally reflected the degree of 
weed
control inputs, with System 5 (nontreat-
ed) yielding the least. Net returns on
these Nsystems xx ithont nmxxiii, we re all
Table 2.Yield and Net Return of Peanuts as
Influenced by 0 to 3 Mowings; 1993-5'
Year System
2
0
1993 1
2
3
4
5
1994- 1
1995 2
3
4
5
3,895
2,927
2,782
2,902
2,105
4,182
4,086
4,177
3,951
3,796
Yield Net return
2 3 0 1 2
lb./acre
3.662
3,168
3,374*3
3,241
1,645
4,080
4,109
4,879
3,864
4,032*
3,483
3,289
3,410
3,241
1,742
3,936
4,105
3,964
3,783
3,704
3,580
3,435
3,556"
3,532
2,347
3,996
4,037
3,719
3,869
3,751
dollars/acre
70 43 58
13 20 42
371 
47  
56'
17 10 41
!93 -270 -143
15 97 107
25 124 114
99 113 75
77 61 89
II 42 67
Rainfall during the growing season (Apr il through August) was 10.9, 33.1 and 17.1"
for 1993, 1994 and 1995, respectively. Long term average for this period is 13.1"
2
Systems are described in Table I.
3: indicates significant difference between this value and the corresponding value
without mowing, according to the appiropriate LSD values at the 0.10 level.
High/litII.s olAricu, ltall Reac hI o. i 44, No. 2, Summr 1997
negalixeC I l(ossexemc. mIl only one inlence
did noxxing hax c a significant heneticial
eflect on yield and net return in 1993. A
single mowing increased the yield ol
System 3 (subadequate inputs) by 2014:
net return increased from -32 to +37 dol-
lars per acre. Two and three mowings
resulted in Lurither (though non signili-
cant) increases in both yield and net
return.
Yields in 1994 and 1995 'ith-
out Imowing also reflected the degree on
weed control inputs. System I and
System 5 having the highest and lowest
yields, respectively. Here again, in only
one incidence did mowing have a benefit.
A single mowing increased the yield ol
System 5 by 6 (r and net return by 421(.
While mowing was clearly beneficial.
this would be generally considered a sal-
vage situation
These results serve to v alidate
the original skepticism against the con-
cept olf mowiig as a means of weedl
control. As expected, mowing lessened
the visual impact of weeds and rendered
the peanut canopy more xvisible. The
impact of mowing on disease occurrence
was varable. Leaf spot-induced delolia-
tion was aggraxated by the lack ol weed
control inputs, and in this case mowing
s.eiwx ed to improxe disease control. In
contrast mowing occasionally
enhanced the occurrence ol1 southern
stei rot. Mowing did improve yield
and net ieturn in a few isolated inci-
dences. Yet even with mowing-based
inproxvenments, crop perlormance
remained inerior to that obtained with
typical weed contiol systems. ('onse-
quently. as a weed control input, mow-
ing can be viewed as marginally eflec-
tive and soimewhat unreliable. A coi
prehensive, her bicide- and ciltixation-
based weed control program can easily
render mnowing unnecessary.
Wehtje is Professor of Agronomy and Soils,
Wells is Superirtendent of the Wiregrass
Substatior, Weeks is an Associate Professor
of Entomology, and Martin is a Professor of
Agriculturaa Economics and Rural Sociology.
NOVEL CHEHICALS CONTROL BRCITERIAL SPOT C
acterial spot, caused by the pathogelt
Xanthomonas axonopodis pv. vesicatorim
is a disease of tomatoes and peppers thai
can seriously affect yield. The disease i
commonly controlled with copper-based bacteri
cides,; Iowever, concerns about copper accumulatioi;
and contamination of soils andI the development o,,
copper resistance in some bacteria are encouragin",i
the development of new bactericides. AAES research
is evaluating the effectiveness of reduced-copper and
noncopper bactericide formulations that have beent
developed for the control of bacterial diseases of
tomato and pepper.
Kocide 2000 and Mankocide
(Griffin Corp.) are new formulations
currently available with reduced cop-
per content (compared to Kocide DF,
the most widely used bactericide on
the market). The products have 53.8%
and 46.08(/o copper hydroxide, respec-
tively, as compared to 61.45% copper
hydroxide in Kocide DE. These were
introduced in an effort to reduce envi-
ronmental contamination without a
decrease in disease control.
Recently, copper resistance
has developed in the pathogen popula-
tion. A new noncopper product, CGA-
245704 (Ciba Crop Protection, Inc.), is
being tested that uses systemic acti-
vated resistance (SAR) to control
hacterlil diseases. SAR refers to the
ability of a product to activate the nat-
ural defense mechanisms within a
plant that will result in disease control.
Field trials were conducted at
the E.V. Smith Research Center in
Shorter in the summer of 1995
and in the summer 
and fall of 
Tal
1996. Pepper cultivar Rangci
was used in the field trials in Treatn
1995. Tomato cultivar Nontr
GX 26
Celebrity was used in sum- GX 30
mers of 1995 and 
I996 and Kocide
tomato cultivar Agriset 761 Kocide
was used in fall 1996. Durin Fluazin
Fluazin
the trial, 
temperatures 
ax c- Fluazin
aged 73?F 
in 1995 and 
71'1 
Incid
in summer and 70?F in fall leaves
1996. Rainfall was 7.25, rerlicat
1Seve
12.08, and 15.29 inches. nodes
11%,1 dUlii t1ie the same period.
In the 1995 trial, various bac-
tericides (see Table I) were applied
weekly to pepper and tomato plants
according to recommended rates. A
total ot 10 applications were applied to
the plants. Disease incidence ratings
were made on July 7 and represented
the nIumber I inlfeted leaxc" pCI
ble I. Results from 1995 Field Trials
ment Incidence (%) I Severity (%)2
eated control 54.6 74.3
6IZ 34.2 75.7
6 52.1 73.8
DF 36.3 78.2
DF + Manex 43.8 76.7
am (0.5 pt./acre) 64.3 70.8
am (0.75 pt./acre) 56.7 71.7
am (1.0 pt./acre) 44.0 75.9
ence represents the percentage of infected
per replicate row. 50 leaves were sampled per
e row (7/13/95).
rity was calculated from the number of empty
on sampled plants (7/28/95).
l/u/uN/flui :1 , l tit ui/Ni .cIp cii,;nh tStation
Higlig~hts ol.Ag~rii u/,ura! Res~earcht Vol. 44, No. 2, .Summ~er 1997
'U
u"
"~
lAY REDUCE COPPER CONTAMINATION PROBLEMS
H. Lee C('a hinell. Mrk Wilson, ad Jan M. Bvrrne
Bteria s('/rot/) oil tomaoes.
rclpihctc Iow. )iscase seseiity (pcr-
centage defoliation) was measured on
July 13 by counting the numihc Of
empty nodes on sampled plant.:, i
proportion of total node number.
In 1995. Kocide III
(GX306) and Mankocide (GX26 Z)
gave control of bacterial spot on pep
per comparable to or better than
Kocide )F' (Table I). Eluainam (ISK
Biosciences) is an experimental fungi
cide with activity against bacteria. It is
a noncopper based product and it did
not provide significant reductions itt
bacterial spot incidence or severits.
In the 1996 summer trial. ha. t-
ricides were applied seekly to tomatoes
accordin to recommended rates. A total
of If) applications sere made. Disease
seeriity ratings on the foliage were
made on June 27 and July 9 and sscr e
based on a visual iating of the total pci
centace of infected foliage on the plant.
In the 1996 fall trial, bacteri-
cides were applied to tomatoes week-
ly according to recommended rates.
and nine applications were made.
loliar disease intensity ratings were
measured on Oct. 17, Oct. 24, and
Nov. I and were based on a sample of
() leaflets per replicate row.
In 1996. Kocide 2()00 and
%lankocidc both gave disease con-
trol comparable to or better than
Kocide DF alone (Table 2) and the
experimental product CGA-245704
reduced incidence and intensity of
bacterial spot of tomato in both
spring and fall field trials. When
applied in combination with
Kocide DF and Manex the percent
disease reduction provided by
CGA-245704 was ereater than that
provided by CGA-245704 or Kocide
These results show that
CGA-245704 gives superior control
of bacterial spot compared to the cur-
rently available bactericides. Because
it works by a different mechanisim.
CGA-245704 might be used in
conjunction with copper/maneb to
improve disease control. Reduced
copper bactericides also gave rcsults
comparable to the most widely used
bactericide. Kocide DF. As more
pathogen races develop copper resis-
tance the market for new chemical
alternatives will continue to grow.
Continued research will determine the
effectiveness of these products on both
tomato and peppe and help deterimnc
thiir Iiture asailability to the grower.
C in ipb I is a Research Specalst, Wilon i
in Assistant Professor, and Byrne is a former
Reseairch Assistant of Plant Pathology
Table 2. Results from 1996 Field Trials
Treatments
Spring
Nontreated control
Kocide + Manex 44.3
Kocide DF 36.7
Kocide 2000 24.6
Mankocide 37.2
Actigard (.03 lbs. a.i./acre)
every 7 days 17.5
Actigard (.06 lbs. a.i./acre)
every 7 days 28.4
Actigard (.06 lbs. a.i./acre)
every 14 days 6.7
Actigard +
Kocide/Manex N/A
Foliar ratings
% Disease reduction
Fall
2
Spring
3
18.1 N/A
16.5 62.6
'Visual ratings disease severity on tomato foliage made 6/27/96.
2
Reduction in foliar disease intensity measured by samples of 30 leaflets per replicate taken 10/17/96.
3
Visual ratings disease severity on tomato foliage made 7/9/96.
4
Reduction in foliar disease intensity measured by samples of 30 leaflets per replicate taken 10/24/96.
5
Reduction in foliar disease intensity measured by samples of 30 leaflets per replicate taken 1 I/l/96.
6
Reduction in disease incidence on fruit, based on percent infected fruit from a complete harvest I I / 1/96.
Aaihama Ao ul /itralI / xpeuimi Staion
ig hliht,;i o/ Aricltrural Re war h V. 44, No. 2, Smner /997
Fr uit incidence
% Disease reduction
Fall
5
Fall
6
I'arslaii
yegrass
DRAMATICALLY
SUPERIOR
UNDER
GRAZING
~I
I
r*
i
- ~-in-lc
i : r*:,
"" ~:.. i:i ---, -
r-
;
a Jr* '"l
~a+l ~1~~ r-
~*~Jrc~;
-- i.
r:~~c~tti: ~
at two locations in
Alabama, on average, Marshall annual ryegrass pro-
duced 52% more animal weight gain than Gulf under
grazing. This result is in stark contrast to results from
mowing experiments.
Marshall is a variety of ryegrass that was developed and
released by Mississippi State University in 1981. It was devel-
oped for its excellent cold tolerance, which makes it particularly
suited to regions with cold winters. In fact, it
i Irated by most specialists as the most
AIld-tolerant variety on the market.
Ilowever in warmer regiols the plant
is not as tolerant to crown rust as Gulf.
Gull is the first improved
variety of ryegrass developed in the
iUnited States. It was released by the
eaas Agiicultural Experiment Station in
1958 for improved yield and improved
tolerance of crown rust. However, Gulf
ryegrass is low in cold tolerance.
Given the recognized difference in
adaptation between these two varieties,
market trends indicate that Marshall is the
preferred variety as one moves North, but
Alabamaa Agricultural Expe/rimnenr Station
Hig~hlig'hts ofAgricultural Research Vol. 44, No. 2, SIumniiiier /9Y7
r
;a;
l)vid 1. lBransbv, MaIIlomnb I-'tues', (I/hi 
Randall RawK/
i~la~r .I
a te ! 
. . W 
r D
.d4..
. s.
-.,,
v,-ln a ,CU 11101C rn the LUII I O&I
reio. Moin tet n lbm
Marshall had a large advant i t. hesl
North. However, mowing does not
simulate grazing. This means that for-
age yield differences from mowing
experiments do not necessarily reflect
animal production differences among
dilferent forages when they are grazed.
Le/i. Mlarshall (feli) cued~ GalI/ (ri~'ii}t oni /h 10, /997.
Belon. Cattle on Malsthall (left and middle) at 
etd of mrald inl
Xpril 1997. Cattle on Gulf (right)
at end of std in Apr i 1/997.
An AAES study
was conducted to compare
Marshall and Gulf ryegrass
under continuous grazi in
both warm and cold environ-
ments. and to relate these
results to data from past
mowing experiments. Stocker
,teers were grazed on four Marshall .mid
Dour Gult ryegrass pastures at the Gulf
('oast Station near Fairhope and the
I !pper Coastal Plain Station near
Winfield in winter of 1996-97. Steers
\eighing about 500 pounds were turned
on to the pastures in early December.
and were stocked at two animals per
acre at Fairhope and 1.67 animals per
acre at Winfield. They were weighed
every 28 days. and pasture height was
measured on weigh days.
At the Fairhope location steer
weight gain was 771/ greater for
Marshall than for Gulf (see Table I). At
Winfield, this advantage was 27%.
However, the stocking rate at Winfield
was above optimum, so this test served
as a comparison ot the two varieties
under stress conditions. Cattle on Gulf
ryegrass at Winfield started to lose
weight in February Therefore, supple-
mental hay was provided for 34 days.
Steers grazing Marshall received no hay.
but still gained 27c% more than those
onGulf. On average, pasture height
across both locations w as 3 11/ greater
for Marshall than for Gull (5.09 inches
and 3.90 inches, respectively).
Of particular interest is the
dramatic advantage of Marshall over
Cult in the Gulf Coast region whcre
Gulf is considered to be well adapted.
This advantage was evident in the very
first 28-day period, and continued to
Alabamia A riidrluriil L-sperinr .Station
HiglihtlsA o/A ric uural Researcl Vol. 44. 
No. 2, Summer 1997
Table I. Weight Gain of Steers Grazing 
Marshall and
Gulf Ryegrass in South and North Alabama
Location
South
ADG Weight gain Weight gain
per steer per acre
Lb. Lb. Lb.
North
ADG Weight gain Weight gain
per steer per acre
Lb. Lb. Lb.
Marshall 2.65 350 700 
1.23 138 230
Gulf 1.50 198 396 
0.97 109 181
Actual difference
(Marshall minus Gulf) +1.15 +152 +304 
+0.26 +29 +49
Percent difference +77% +77% +77% 
+27% +27% +27%
Note: I )ln the South stocking rate was two steers per 
acre and cattle grazed for 132 days, but
in the North stocking rate was 1.67 steers per acre and 
grazing was terminated after 1 12 days.
2) In the North cattle grazing Gulf were fed hay for 
34 days in winter at a rate of 16.9 pounds
per head per day, but cattle grazing Marshall ryegrass received 
no hay.
(sece lable 2). Ihis shows that, in this
season, the superiority ol Marshall
was evident throughout the entire sea-
son, and not only in the middle of win-
ter. Clearly, Marshall was superior to
Gulf in both cold tolerance and toler-
ance to grazing, and it may also have
some other production advantages that
have not yet been discovered.
Rust was evident on both
varieties in spring. It was more severe
on Marshall, btt did not seem to affect
animal production. However Jackson
ryegrass is a variety that was devel
oped from Marshall, and it has similar
cold tolerance but greater tolerance 
to
crown rust. Therefore, it rust is of con-
cern, Jackson can be used as an alter-
native variety to Marshall. This variety
will be included in future experiments
for comparison with Marshall and
Gul f.
An economic analysis of
these preliminary results suggests that
Gross receipts (Dols./acre)
Total costs (Dols./acre)
Net income per acre (Dots.)
Marshall ryegrass was more prolfitable
to graze than Gulf. If animals were
contract grazed by a landowner for 35
cents per pound of weight gain, paid
by a separate person who owned the
cattle, profit from cattle graling
Marshall was nearly five times high-
er Ihau for Gulft( l'0 ,t '.l i
Variety of Ryegrass
Marshall Gulf
245.00 138.60
118.79 114.89
126.21 21.71
Ryegrass variety
Marshall
Gulf
Difference
(Marshall minus Gulf)
0 28 56
Lb. Lb. Lb.
522 612 700
522 588 654
0 +24 +46
0% +4% +7%
521.71: see ITable 3). IThis occurred
despite a $3.90 lower seed cost per
acre for Gulf (the analysis assumed 
a
seeding rate of 30 pounds per acre
and seed costs of 30 cents per pound
for Guilf and 43 cents per pound for
Difference
(Marshall minus Gulf)
+106.40
+3.90
+102.50
Marshall). Theclore, based on this
study, an extra $3.90 per acre spent
on seed for Marshall ryegrass 
gave
$102.50, or nearly a 27-fold return on
investment.
These results suggest that
Marshall ryegrass was dramatically
(u~ro IO Gulf ii '-lhoit thOw~~i
84
Lb.
768
691
+77
+1 I%
112
Lb.
852
726
+126
+17%
132
Lb.
870
720
+150
+21%
e\en at the Gull Cioast; the prilit
advantage was substantially greater
than the production advantage; and
the advantage of Marshall over Gulf'
was much greater under grazing than
under mowing. In addition, profit from
tockers grazing Marshall ryegrass
was comparable with many row crops.
ransby is a Professor of Agronomy and
soils, Pegues is an Assistant Superintendent
Cf Guf Coast Substation, and Rawls is
)aperintendent of Upper Coastal Plains
Higlil AArR r icla V _qrl. 44, N 2lqin SSuom iol
Highlights nffAgricultural Researclruh Vol. 44, No. 2, Sumner 19 /'97
Ryegrass variety
Table 2.Change In Steer Weights Over Time for
Cattle Grazing Marshall and Gulf Ryegrass 
at Fairhope
Table 3.Stocker Steer Economics for Marshall
and Gulf Ryegrass at Fairhope
re s care hcrs.
working with the U.S.
Department of Agriculture's
National Animal Disease
Center (USDA-NADC) in
Ames, Iowa, have developed
a rapid, specific procedure
the diagnosis of Cam-
hxlob cer fitus, a bacterium
that infects humans and cat-
tle and poses risks to human
health and can cause severe
economic loses for cattle
producers.
C. ft.s has been divided into
two subspecies: C ftus .subsp. fetus and
C. ftu.s subsp. i'enerealis. Although
infrequent. human toodborne outbreaks
of C. /clu.s subsp/. /etus. have resulted
irom the consumption of raw beef, raw
milk, and cottage cheese. In a two-year
surveillance study, from 1987 to 1989.
the Centers for Disease Control and
Prevention (CDC) reported 122 human
cases of C. frteis .sub.sp. frtus. In cattle
and sheep, C. fetu.s .suhp. /ets is
transmitted orally. The organism dis-
rapt, the JILWC t t induCC, ahrlHOit. .iiid
produces infertility.
There is no report of human
infection due to C'. fius .sub.sp. vencere-
alis. This microorganism is regarded
exclusively as a venereal pathogen of
cattle.
Trade restrictions prohibit the
export of bulls carrying C. frru.s .subsp.
venerealis. Typically. diagnosis of C.
feat.s subsp. venereali.s is accomplished
by observing clinical signs of infection
or by examining samples of cervical
mucus, preputial washings, or intestinal
contents of aborted fetuses under a high-
powered microscope. Unfirtunately, it
is easy to confuse C. fetus .suhsp.
venerealis with similar nonpathogenic
bacteria. Biochemical testing also can
be used to detect C. feus. but this
method is time consuming ard impre
cise. Finding a more specific and rapid
method to detect C. frnu.s would speed
up testing for the bacterium and also
help laboratories avoid potential confu-
sion of dangerous organisms with harm-
less organisms.
AAES scientists joined forces
with researchers at USDA-NADC to
develop such a test, which uses a poly
f)Iudii 100c (fromCniphilohaceir andir
Arcohacter spp. M. 111( bs, Marker: 1-4. C.
fetus showing the 554 bp) amlIfiatlion: 5:
C. hyodintestinals, h: C. spur)1run. 7: C.
jejuni, 8: C. coi, 9. A. hutzlri, /0: A.skir
rowii shon u, no cmiii i foil
merase chain reaction (PCR) technique
and amplifies DNA to detect both sub-
species of C. fetus. The PCR technique
separates the DNA from (ampylobac-
ter-like bacteria. These samples can he
used immediately for testing or can be
frozen for several weeks for later evalua-
tion. The PCR technique can yield reli
able idertitication of C. fetus within
three hours after isolation of suspicious
colonies on agar plates.
This work provides a powerfil
tool to investigate a disease that results
in both a loss in animal production and
a risk in human health. This technique
can help expand knowledge of the
transmission and epidemiology of this
bacterial pathogen.
Oyarzabal is a Graduate Research Assistant
and Conner is an Associate Professor of
Poultry Science; Barbaree is a Professor of
Botany and Microbioiogy; and Wesley is a
Leading Scientist with the Enteric Research
Unit, USDA-NADC.
Alabama Agicltu ral Eqeriment Station
Hihllighlrts of Agr icultural Research Vol. 44, No. 2, Summiner /997
POTASSIUM FERTILIZER PLACEMENT
EFFECTS ON UPTAKE AND ROOT
LENGTH DENSITY
OF COTTON:ER SUMMARY
Greg~ Miu/lin, GrgPe
:. number one row crop in Alabamat
in terms of acreage planted, with
more than 540.000 acres planted
to cotton in 1 996. A major
concern of cotton producers is
the appropriate application of
potassium (K) fertilizcr to ensure
'-4 31the crop is both high yielding
and of high quality. Recent
'fit 
AAFS studies 
have shown that
traditional suirlace application of
K fertil izer or incorporation of K
' into the plow layer is sufficient
md more cost effective than deep
placement of K for cotton
pflI uction in Alabama.
5- 1'1tassiUml fertility ini 
cotton has
Kcnit concern of' pI oducet since the
carIy I f9()s when potassium eficiency
w\mponm were first identified by G.I.
\tkinson of' the Mechanical and
\gricultural College of Alabama (now
\uburn Univ ersity). Symptoms that i
tially had been mistakenly attr ihuted to a
pathogen and given the name "c otton rust"
s\ere final ly and corrt ly atributed to a
lack of 'potash in the soilI.
I iic clI pola' ' 1 I)! il l('m In t olon The 
lack of soil potash decrecases
lint yield and reduces limnt qunalit',. In
16 Alabama/i Aiciilniu-al 11 ~w/7iew Station
Hig~h/lits1 of Agricultural Researc Vol14. 44, No. 2, .Summer 1997
i rrriisc Ii) .1 IC Cl t L IIIClICa' Ini icPrrIi
of late season K dleficiency tlhr oughout
the Southeast, researchers in the region
have explored ways to incr ease the
amount of K in the plant late in the sea
son, thus avoidting late season K defti-
ciency. These studies focused either ot
deep placement of K fertilizer in the tow
or application of K fertilizer as a foliar
spray. How ever. the> did not answ er
many of the basic questiots important to
the understanding of K uptake and the
cotton plants ability to remove K Irom
the soil.
'io answer these questiotns.
three-yeat studies were initiated by
AAES researchers in 1992 at tli
Tennessee Valley Substation in
Belle Mina (Decatur siIt loam) and
at the Prattville Experiment field
in Ptrattville (Lucedale fine-sanmd\
loam). In the studies, exact place
mert of' K w as made at diIfereIt
depths w ithii the soil profile.
Treatments were applied by inject
in a potassiim chloride (KCI) solu
tion into the soil at various depths
from the surface to 21 itches.
Treatments in which increasing pr-
portions of the soil profile being lcr
tilizcd were also included as well as
banded K ard foliar K treatments.
Whole plant weights arid K
concentrations were determined arid
used to calculate total K tuptake for
each treatmenit.
Restlts of the two studit,
averaged over the three-year stutid
(see table) showed total K tuptake for
surface-appliet K and injection (of the K
solution at a particular depth within the
soil profile did not differ. Consistent
increases in total K within the plant
were observed ottnly atimotng suface
app!ication of K aid treatments in
which an increasing amount of' the soil
profile was fertilized. Elfectiv ely fertil-
izing the soil to a depth of 21 inches for
the Iecaturt soil and 15 inches for the
Lucedale soil, increased K tuptake over
surface applied K treatments. As the
propO111011 ca , l , h C s ill v uLIHIC that 1> ICI- "
til ied icceased. so did the amount of K w'
taken into the plant. No response to an
bandin- K fertilizer was obser\ved. how-
Cver. cotton does not typically respond to
to K fertilizer applied as a starter. di
The Decatur soil did not an
respond to foliar applications of K but pl
the Lucedale soil did show an increase of
in total K by foliar treatments when lit
applied in conjunction with I 1) pounds ar
of KO per acire of soil-applied K. Both ar
soils tested low or medium for soil test of
K in the lo ~ii ad n I ()vv i! hi oil IcI K ini Ici
Total K Uptake Averaged Over a
Three-year Period (1992-1994)
is detcrmll
d depth it
Th
cations fi
IifCrcnccs
.d trcatn
aced at a
K fertili
eration o
ea treated
e contain
the soil
IIt hl dii
Placement Total uptake (Lbs. K/acre)
Decatur soil Lucedale soil
Surface 91 57
Injected at 3 inches 89 55
Injected at 9 inches 87 66
Inected at 15 inches 90 57
Inected at 21 inches 81 58
Injected from surface to 3 inches 92 76
Intected from surface to 9 inches 95 78
Infected from surface to 15 inches 99 85
Injected from surface to 21 inches 109 73
Band on surface
2  
83 68
Band at 9 inches 87 63
Band at 15 inches 94 59
Foliar3 - No soil K 68 62
Foliar + soil K at 3 inches
4  
75 74
Foliar + soil K at 9 inches 85 75
1 Solution injected in sequential depths relating to the surface; 3,
, 15, and 21 inches and ending at the specified depth. Each treat-
nent represents an increasing proportion of the soil profile being
effectively fertilized. Solutions were adjusted such that a total of
120 pounds K
2
0 per acre was applied.
2 Band applications made approximately four inches to the side
of the row at the specified depth.
3 4.4 pounds of K20 per acre of foliar K applied four times at
two week intervals beginning at early bloom.
4 120 pounds of K
2
0 per acre soil-applied K plus foliar K.
the subsoil. No explanatio can be given will rot be
for the respotse observed on the and elfectiv
Lucedale soil arid the lack of response file dowi to
observed on the Decatur soil. sible for pr
Root length density for each researchers
treatment was calculated to determine application
the effects of K fertilizer placement on into the plo
root length density and distribttion in ton grown ii
the soil. Soil cores of 1.25 -inch diate- Mullins 
is a
ter were taken in four positions (in-row. Graduate Res
5. 10. arid 2(0 itches awa> froom the is a Extensionl
row). The soil cores were cut into fotI.
I) i il 0liiiLI5 Root I iL111
ined for each row position
icrement.
ese ieasurmetis lot both
led to reveal any consistent
among surface applied K
tents in which K was
single depth. Placement
zer did not lead to a pro-
I cotton roots atound the
I. Most of the cotton roots
ed in the top 0-1 Iiiches
mnd close to the row. Root
its data mirrored that of'
total K uptake in that
increases in root length
density came only by
lf ectively fertiliizing
the soil profile to 21
inches for the )ecatur
soil and 15 inches for
the Lucedale soil.
Results F'ront
this study show that
deep placement of K at
a patticula depth was
niot superior to surface-
applied K for increasing
K uptake or root length
density of cottot. ()iIly
\\ hen a large propotioi n
of the soil prolile was
elfectively fertilized
w as K uptake and toot
length density of cotton
significantly increased
as compared to surf ace
K applications. )eep
placement applicators
effective on Alabama soils
ely Iertilizing the soil pro-
15 or 21 itches is rot lea-
-oducers. As such. AAL:S
conclude that surf ace
of K ot itcorporation of K
V layer is sufficient fot cot
Alabama.
Pr ofessor, Pate is a former
earcr Ass stant, ano Burmester
Research Cotton Spec ialst.
Alabama Agricrltural xcpr moerm Sttionou
Highlightslof (Agiricultural ResearchI Vol. 44. No. 2, .Simme~ir' 1997
v&RcA LEAP iW I I N
TESTED FOR USE IN
ALABAMA'S GULF COAST
PPC
1
r mKJ
Michaelh Pateron. an Moliom Pcl)h Ii/A~
replen ish Soil mnoi stille. These same
conditions also regulairly lead to sexvere
boll rot due to hieh humiditN , excessixve
xvegetatixve growth, aind reduced Sunligeht
and aii peCnet ration)f inito t he canopy
An AA[ S study xwas conduct-
ed at the GUilf Coast S obstation.
I arhope. from 1994 to 1996 to deter-
mine if an okra leaf cot to n i (i ht have
.alx antaees over coiixentional Ical cot-
ton by increasing an, mox emcnl and
li eht penetration to reduce dainae
From boll rot organisnis. Okra leaf cot-
ion is xwidely grown i in Australia. but
,)ll rarely in the United States, due to
Iixxer yields. Recent research suggests
narrow row spacings and higher seeding
r ates may help close the yijeld gap
hctx ceo okra leaf cotton and conx en-
i i I ir tes
mxentijonal and okra leaf
I the experimental xvariety
\l l)i lIe. wxhich differ only in the shape
of theii leaxes, xweie planted in 31) and
36- inch rows, in combination wxith
seeding rates of three or six seeds per
ioot of row. Plant growxth and dcxvelop-
mient wxas measured b\y collecting data
in plant heights and nodes and their
ration (to indicate howx rapidly the cot-
ton was growinme), and initiation of the
first fruitine bianch. wxhich indicates
earlier ilaturine and hi'Lher xvalue fruit.
%u. otton acreage 
in Alabama's Gulf 
Coast reeio haetsfLafSa
experienced a resurgence in recent years thanks to favorable Leaf shape Abscission
Ili "s'~ its vu ai a~i rottion (crot n w teMk i(hnlo tlies. ,.uch tt. 1994 & 96
VCILI cc,, p, g ~ L L*i Cjt IV tSfh
growth regulators and higher capacity harvesting machines.
The Gulf Coast region's deep sandy soils and lone eroxxing ,casion
are well-suited for cotton production, and Iirequent Suimmer thundm stomls
Conventional
Okra
e on Cotton Growth and Yii
Open
994 & 96
Pct.
42
56
Seed cotton yiE
2,502
2,247
Alabama Agriultural Ek ~wrim'nt Station
High/il i,'/i of A 14/ itial ReCa('(,Yl Vol. 44. No. 2, Suaomer 1997
DEVEI 
!?Ni
SIMPLU
At maturity. abscission (boll shed):
percent open, closed and rotten bolls5:
and seedcotton yields wxere measured.
There was a varying response
of plant height and internode length to
leaf shape in 1994 and 1996. Lowxer
seding rates and closer rowxs increased
number of irepr oductiv e nodes in 1994
and 1996. None of the treatments affect-
ed first trnliting, branch initiation.
Little boll rot xxas priesenit in
any treatment in 1994 or 1996, so that
no differences could he measured.
[Hurriicane Lrin in August 1995, fol-
lowed by Opal in October flattened the
crop aiid cansed ececssix c boll rot anid
shed, obscuri ng any treatment effects.
Several differences occurred in
1994 and 1996. Closer irows resulted in
taller cotton. Okira leaf cotton opened
eairliei (see table). wxhich xxouild allowx
fanrmrers to hai x st dur inrg typically dry
fall w xeather, but it also had higher
abscission rates for first-position truit.
Convenitionial cotton out-yielded okra
leaf cottoii iin 1994 and 1996. while they
were equal ini 1995 (1,709 pounds of
seed cotton per acire).
Ini conclfusion, okra leaf cotton
did nIrot decrease boll rot ini these
tests. Ev en wrth closer rows arid high-
er seedi ng rates, okra leaf' cotton
often had a lower yield. 1-1iglier-yield-
ne okra leaf li nes must be dex elop;
for okra leaf cotton to finid a place )
Alabama's Gulf Coast.
Delaney is an Extensior Associate, Monks
an Associate Professor, ard Patterson i
Professor in Agronomy and Soils. Pegues
Assistant Superintendentr of the Gulf Coas
Substation.
INEXF
TESTS
FOR LLA\i
Y-H. Pci,tx Hsich, liri, Ii (Ium.
(111(1 ,S'axn-C'/,ocn ,S'heli
m -w
a.I
By avplesdmeat '
products must be labeled to indicate
all species of meat products they
contatn. This is important for peo-
ple whose religTious practices llrtt 1 h 
./i~ ., .i s (hI (/0/nd Irv kit iu'cd
the types of' meat they eat, for peo- t' delen mra .crie in ii /11Th ('tA ct hi
ple who have 
allergies to 
certain prdcs
types of meat proteins, and to ensure that consumers cook meat pr'operly
to kill any food-borne pathogens. However,' detecting meat that may have
been adulterated with undeclared meat proteins is dif'ficurli. AAES
reseat'ch, however, has developed monoclonal antibody tests that make
species detection in processed meats more rapid and accurate.
Widespread Species adulIteratioris hiaxe r'ecenitly been documented amon1e2
rawx and part icu larly heat-processed ground meat products in A labamna arnd oither
domestic retail markets. At best, adulteration is the result of imirpr'oper handlIinrg.
At wxorst, it is an inrtenitionial piractice ot' economric fraud,
Although11 many methods lhixe been developed ini the past 20 to 25 years
to identify meat species, one of' the best methods is the use of' enzyrne-linked
ni iii llm t1) ibc ;Ii t II f 1S i i li, 1,1io hlils sensitive, 
specific.
aid Simple to uise.
Monoclonal Antibodies Developed to I loxxexer, 
species-spe-
Identify Commonly Used Meat 
Species ,if ic antibodies 
must be
in Raw and Cooked 
Products 
used iii FLISA tests 
foi
Monocloanal antibodies Subtype Specificity i cuirate ieat spiecies
2F8c I Gs7Th k-,,.i b ,,,f I b h eItection.
3E1 2
5D2
9C6
5H9
porI ,, uee , am; , orse1 a,
and deer
chicken, turkey, and duck
chicken and turkey
chicken
pork
T her e are txxo
iIr P1'f prc.'ih's spiif
Meat Products,
Wrt inieJ 111 pagec 20
Alhi/ama0 A gri( uillund o E \/i lieni IStation~
Hiiglights o/ Agr4icuolturatl ResearchI Vol. 44, No. 2, Summert 1997
S
Meat Products, continued from page 19
cili anim (odies. poIN cloiial and mn
oclonal. Both can he used in the
ELISA system. Because monoclonal
anti-bodies are biotechnology derixved
an unlimited supply of' well-def'ined
reagents can be ensured. An AAFS
study initiated in 1993 has focused
on the dev elopinlt of inonoc lonal
antihbodies for meat species identifi-
cation in both raw and cooked meats.
So far, this project has pro-
duced fixve monoclonal anti bodies (see
the table) that aire tised in F IISA test-
ing, to identify species. Results of the
test can be vi sual ized in a few iinuteS
hs L~i~il Irh nbe (sec ith phii1oo.
These antibodies repiesent
br'eakthroughs in several testing issues.
For example, some of these antibodies
are able to di stingeui sh mammalian
meats fromh poultry, xich prex iously
had not been possible. In addition, all
the AAFS-developed antibodies can be
tised for both raw and heat processed
meat products. The antibodies can be
used to dletermine hoxx much of each
meat species is present ini a sample and
these antibodies can help predict the
nternal cooking temperature of the
precooked meat for food safety con-
cerns. To date. one antibody specific to
chicken and one specific to pork hax e
beeCn dLcclpcd to Jdeniisl% n~
species. Research on other antibodies
and methods for other meat species is
on-o come.
These research dexvelop-
inents wxill aid in the battle of ille-
gal ly processed or imisl abeled meat
products. Use of these monoclonal
antibodies wxill signi ficantly reduce
the present cost of the assay by at least
50/.They can be made in to conve-
nient kits to rapidly test a large
number of samples for nouIti species
n a laboratorv setting. Since the test
s simple and i nexpensix e, it can be
dexveloped into single field kits for
use by inspectors in mneat pr ocessi ng
F;RATIJM: This table appeared in the W~inter 1996 issue of Highights, "Alabama
lonnat) G;rowers Meeting Federal IPM G;uidelinies," page 7, Vol. 43, No. 3 Nwith an error.
The acreage for IINI categories in Georgia w as show ii as 50. It should halve beeni 100, as
showni here. The editors reg~ret any confuisioni.
Summary of IPM Survey Results
State
No. Avg. farm Avg. score
growers size, acres
Alabama
Georgia
Kentucky
North Carolina
North Florida
South Carolina
Tennessee
22.1
69.5
6.8
(3.3
213.33
(32.2
20.6
Pct. medium and high
PM categories
Growers Acreage
65 66
100 100
93 99
66 94
00 100
94 99
67 63
Avg. no. applications
Fungicide Insecticide Herbicide
9.7 9.8 2
14.6 (4.2 I.5
10.2 7.2 2.1
11.6 7.7 1.7
9.5 (6.4 1.9
11.8 9.9 18
plants and stores and
by consumers in the
home. The tests also
haxve great potential
for commeircialization
and a patent is cuirrent-
I y pendling on this
techniiology.
i ieh is an Assciate Pro-
fessor, Chen is a Graduate
Reseasrch Assitaut, and
Sheu is a former Graduate
Research Assistant of
Nutition and Food
cencer
ALAAM A\G\I \RIC LI tURAt E XPERIMNTN S T.\ ION
AUBI'RN UNIVE(RSITFY
AUBU1RN UNIVERStITY. AtLABAMA 36849-54(03
.iames F. Mrv~tion. D iirector
t'( S'T NISIR-Address ('oiciun Requescted
20) Alabamia Agric~ultural F xpwrimocn Station
Higlights of Agricu/ltural Resear ch Vol. 44. No. 2, Sumnierc 1997