Research Update
-,_?19 89
? SOYBEANS
"-3 ii I- ;;
NEW REPORT INAUGURATED
This is the first report in a new
research series, called "Research Up-
date," being inaugurated by the Alabama
Agricultural Experiment Station (AAES).
The new series is meant to promote timely
reporting of research results to producers
of specific crops or commodities. Each
report will be identified with the crop or
commodity and year-"Research Update
Soybeans 1989" in this case. Others will
follow the same pattern.
Plans call for annual issues of the
Research Update series to assure that lat-
est research information from Auburn is
made available to producers. Efforts will
be made to maintain up-to-date mailing
lists so all Alabama producers will receive
the reports.
Today's highly competitive con-
ditions make it doubly important that farm-
ers have available the latest scientific in-
formation. This new publication series is
being produced to help meet that need.
Other information about soy-
bean production and latest recommenda-
tions are available from each county Exten-
sion Service office in Alabama.
Mo, LIME INCREASE YIELDS
Soybean yields increased with
applications of lime, molybdenum 
(Mo),
or both in research on two AAES substa-
tions and on farmers' fields where soil pH
was low. Response to Mo varied from
one field to the next, and use of Mo did
not eliminate the need for lime on acid
soils. However, cost of a Mo seed treat-
ment that will supply Mo needs was so
low that even a l-bushel per acre soybean
yield increase would more than pay it.
Therefore, small yield increases were
profitable.
Yield responses in plots that
had been in long-term fertility 
studies,
summarized below, show the value of
lime and Mo in north Alabama:
Yield
Lon g-term treatment
(?ime-fertilizer) Tenn
No M
Unlimed fertilized
(pH 4.8-5.4) ......................... 28
Limed-fertilized
(pH 5.6-6.0) ........................... 37
Limed-not fertilized
(pH 5.0-5.8) ........................... 21
No lime or fertilizer until 1979
(pH 5 8-6 0 ) ............................ 24
per ac
Vail.
Io Wi
Results from an acid Vaiden
clay soil in Perry County illustrate value
of Mo on fine-textured soils of the Black
Belt when lime is not added. At soil pH of
5.0, yields were as follows:
No lime-no Mo................... 19 bu.
M o added............................ 27 bu.
Lime added ........................ 29 bu.
Lime, Mo added ................ 29 bu.
Slight yield advantages showed
up from both lime and Mo in tests on 15
north Alabama fields, where pH ranged
from 4.6 to 5.6, as follows:
No lime-no Mo................... .25 bu.
M o added .............................. 32 bu.
Lime added ............. 34 bu.
Lime, Mo added................36 bu.
Because of these results, the
Alabama Coopera-
tive Extension
re, 1985-87, bushels Service now rec-
ommends Mo for
Sub. Sand 
Mt. Sub. 
soybeans 
on all
th Mo No Mo With Mo soils 
of north Ala-
bama and on fine-
40 18 33 textured soils in
other areas of the
40 32 
37 State.
31 12 
17 Charles 
Mitchell
and C.H. Burmester
32 30 36
COTTON-SOYBEAN ROTATIONS
BOOST YIELDS OF BOTH
Recent results from the Brewton
Experiment Field strongly indicate that
rotating soybeans with cotton can greatly
improve yield of both crops without in-
creasing production costs. Thobeneficial
effects of soybeans on cotton were ap-
parent the first year of the rotation and
the effects continued through the 4-year
test period.
For the 4-year period reported
in the table, seed cotton yields averaged
about 500 pounds per year higher when
soybeans rather than cotton was the pre-
vious crop (soybean-cotton rotation).
The beneficial effect of cotton on soybean
yield was not noticeable until the third
year. During the third and 
fourth years,
however, soybean yields averaged 14
and 21 bushels per acre higher when cot-
ALABAMA AGRICULTURAL EXPERIMENT STATION AUBURN UNIVERSITY
LOWELL T. FROBISH, DIRECTOR AUBURN UNIVERSITY, ALABAMA
I
ton rather than soybeans was the previ-
ous crop.
Using values of $0.80 per pound
for cotton lint and $6.50 per bushel for
NO-TILL, STRIP TILL SHOW
PRODUCTION ADVANTAGES
Using conservation tillage in-
stead of conventional tillage in soybean
rotations at the Sand Mountain Substa-
tion, Crossville, resulted in (1) delayed
build-up of crop-damaging cyst nema-
todes in the soil, and (2)
higher soybean yields. This
was true with rotations of Cropp
soybeans-corn and wheat- systE
soybeans-corn. Further-
more, the rotations in most Continuou
cases increased soybean Soybeans
yields over continuous soy- 
Wheat-soy
beans.
The two conservation tillage
systems tested were (1) strip tillage (kill-
ing the wheat with herbicides, tillage
with a chisel to 12 inches, pulling soil
over the chisel area, and planting; and
(2) no-tillage (planting in the killed crop
residue with a double disk-opener
planter). The conventional tillage com-
pared was moldboard plowing the wheat
cover in the spring, disk incorporation of
herbicide, and planting conventionally
on the surface.
Plots with conventional tillage
had a quick build-up of cyst nematodes.
In contrast, conservation tillage plots had
slow populationbuild-up. In fact, theless
tillage used, the slower the populations
developed. Cyst nematode counts were
beginning to pick up at the end of the 4-
year test, but strip tillage production
continued to show highest yields with
Essex variety soybeans. The highest in-
dividual average yield was 39 bushels
soybeans, the crop rotation in the fourth
year alone would have increased gross
income $189 per acre for cotton and $137
per acre for soybeans.
J. T. Touchton
per acre from both no-till and strip-till
soybeans rotated with corn. Corn in the
rotation averaged about 137 bushels per
acre for conservation tillage systems.
Four-year average yields under
the three tillage systems are listed below
for continuous soybeans and for both ro-
tations.
D. L. Thurlow
ing Yield, by tillage system
em Conventional Strip No-till
s soybeans ........23 bu. 30 bu. 35 bu.
-corn ...... .... 32bu. 39 bu. 39bu.
ybeans-corn ....... 35 bu. 36 bu. 31 bu.
MODEL BASED ON WEATHER
ASSURES FUNGICIDE PROFITS
Midseason diseases of soy-
beans, including frogeye, anthracnose,
and brown spot, reduce yields by up to 20
percent in Alabama. Recent 
AAES re-
search indicates timely treatment of these
diseases with recommended fungicides
can provide a big payback for growers.
To provide a guide for growers,
a model based on weather factors was
developed. Since these midseason dis-
eases affect yield only after flowering (RI)
and during podfill (R2-R5), the model is
designed to monitor soybeans only dur-
ing these growth periods.
Effect of Crop Rotations on Soybean and Seed Cotton Yield at the
Brewton Experiment Field
Per acre yield
Cropping system 1984 1985 1986 1987
Soybean yield, bushels
Following soybeans (continuous) ........ 41 29 15 11
Following cotton (rotation) .................... 44 30 29 32
Seed cotton yield, 
pounds
Following cotton (continuous) .............. 3,000 2,630 2,610 2,310
Following soybeans (rotation) .............. 3,300 3,370 3,010 2,950
VARIETY, ROTATIONS MORE
VITAL THAN NEMATICIDES
While nematicides are 
impor-
tant tools in fighting yield-robbing nem-
atodes, these chemicals can't replace
good varietal selection and crop rotation,
according to recent AAES results.
Seven of the top soybean vari-
eties grown in Alabama were compared,
and each of these varieties was planted in
plots treated with 2 pounds per acre ac-
tive ingredient of Temik? and in un-
treated plots. Soil in these plots was
heavily infested with peanut root-knot
and cyst nematodes. These varieties,
which differ in nematode resistance,
were also planted in plots following 1
year of corn and in a continuous soybean
monoculture.
Braxton in nontreated plots fol-
lowing soybeans produced only 23 bush-
els per acre in 1987. The same variety
following soybeans, but with Temik,
produced 32 bushels per acre. Braxton
beans grown in plots that were planted in
corn the previous year, and not treated
with Temik, produced 45 bushels per
acre. Adding Temik to the corn-soybean
After the RI stage, records are
kept, and when 2 or more days of rain, ex-
tended fog, or heavy dew are recorded in
a 4-day period, plus 2 more days of pre-
cipitation are predicted in the next 5-day
period, application of a systemic fungi-
cide, such as Benlate?, is made. If a fun-
gicide is applied at this time, records need
not be kept for the next 8 days. After 8
days, record keeping resumes, and if
moisture occurs 2 days in a 4-day period
and more is predicted for 2 days out of the
next 5 days, a second fungicide applica-
tion is needed. In this manner, up to three
fungicide applications may be made
during podfill (R2-R5).
The perception by many soy-
bean growers is that fungicide use is only
marginally rewarding, and above aver-
age prices are necessaryto profit from the
use of these chemicals. This is not the
case. Even at prices of $6.00 per bushel,
the predictive spray program repeatedly
paid for itself and provided a good profit
on investment. Programmed spray
schedules, on the other hand, sometimes
paid and sometimes didn't, providing a
large element of risk for growers.
Paul Backman
I i
I I
rotation increased yields to 53 bushels
per acre. The other varieties in the test,
Centennial, Forrest, Gordon, Kirby,
Leflore, and Ransom, also had higher
yields in rotation plots versus nemati-
cide-treated ones. Kirby and Leflore each
had about a 5-bushel per acre advantage
for the rotation, compared to a 10- to 15-
bushel advantage for the other varieties.
Each of the varieties in plots fol-
lowing corn showed a positive response
to Temik. Forrest, for example, showed a
12-bushel per acre advantage for treated
versus untreated plots planted in rotation
with corn. The average response of the
seven varieties was about 7 bushels per
acre in the plots that followed corn. In the
soybean monoculture, the average of the
seven varieties also showed a 7-bushel
per acre advantage for treated versus
untreated plots. The average of all varie-
ties in the soybean monoculture treated
with Temik was 36 bushels per acre,
compared to 46 bushels per acre for the
corn-soybean rotation, without the ne-
maticide.
The top net dollar return among
varieties and treatments in the test was
from Braxton, treated with Temik and
grown in a soybean/corn rotation, see
table. This combination produced a net
return of $203 per acre. Braxton, Forrest,
and Ransom varieties showed negative
returns of $39-$93 in plots planted in a
soybean monoculture without using a
nematicide. Leflore, which is resistant to
SCN, but susceptible to root-knot nema-
todes, showed the smallest return ($72)
from rotations.
The average net dollar return on
soybeans following soybeans, using no
nematicide, was only $3 per acre, com-
pared to $94 per acre using a nematicide
and rotating with corn. By rotating with
corn, average soybean returns were $157
per acre without nematicides and $164
with nematicides.
R. Rodriguez-Kabana,
David B. Weaver, and Emmett L. Carden
Economics of Crop Rotation and
Nematicide Use in Nematode-
Infested Fields, 1986-87
Net return/acre
Variety & Corn Soybeans
nematicide Cnematiide-soybeans 
-soybeans
Dollars Dollars
Braxton
No ... ............195 -69
Yes............ 203 39
Centennial
NoYes .................. 173 129
Forrest
No ..................... 93 -39
Yes ........145 -3
Gordon
No ... ...........153 27
Yes ............ 143 93
Kirby
No ................. 165 69
Yes............161 162
Leflore
No.................. 
159 
87
Yes.................. 179 162
Ransom
No............... 147 -93
Yes........143 78
All varieties
No ................... 157 3
Yes ................... 164 94
1 Temik (2 lb. a.i./acre = $40).
2 1986 corn total cost (fixed and 
vari-
able) = $182.00/acre; 1986 soybean
total cost (fixed and variable) =
$157.00/acre; 1987 soybean total cost
(fixed and variable) =- $146.00/acre;
corn @ $2.30/bu.; soybeans @ $6.00/
bu.; 1986 corn = 110 bu./acre.
I _____ T_ ____1 __~ 1_~___~_-1- _ -- I ( ~IV*
BAHIAGRASS ROTATION UPS
SOYBEAN YIELDS
The banning of nematicides
containing dibromochloropropene
(DCBP) and ethylene dibromide (EDB)
by the EPA several years ago left soybean
farmers without their most effective and
economical means of controlling yield-
robbing nematodes. Thus, crop rotation
and varietal selection are essential tools
to manage nematode problems. Recent
AAES research discovered some interac-
tions among these tools that could im-
prove soybean yields and reduce pro-
duction costs.
Tests were conducted on light
sandy soils in southern Baldwin County.
Gordon, Centennial, Braxton, Kirby,
Leflore, Ransom, and Stonewall soybean
varieties were planted in plots that had
been in Pensacola bahiagrass the previ-
ous 2 years. These were compared to the
same varieties planted in plots on which
soybeans had been grown the previous 2
years. In each of the two cropping sys-
tems, each variety was planted in plots
treated with aldicarb (Temiks) and in
plots with no nematicide.
As expected, yields of all varie-
ties in the bahiagrass rotation were
higher than the same varieties in continu-
ous soybeans. The average yield increase
in the bahiagrass rotation plots was 110
percent. However, 
not all varieties re-
sponded the same to the bahiagrass rota-
tion. Braxton, for example, showed a 233
percent yield increase over plots planted
continuously in soybeans, but Leflore
showed only a 33 percent increase.
Race 4 cyst nematode numbers
were lowest in Leflore plots, regardless of
cropping system. The nematicide treat-
ment did not increase yields or reduce
nematode numbers in the soil, regardless
of variety. The highest number of root-
knot nematodes was found in Leflore
plots grown in the soybean monoculture,
while Race 4 cyst nematode numbers
were lowest in Leflore plots, regardless of
cropping system.
R. Rodriguez-Kabana,
David B. Weaver, and Emmett L. Carden
VARIETAL RESPONSE VARIES
WITH ROTATION CROPS
Pioneer 8222 sorghum, Ameri-
can joint vetch, and hairy indigo were
recently tested for use as rotation crops
with seven leading soybean varieties in
the State. AAES test results indicate that
different varieties of soybeans responded
differently to the various rotation crops.
Each of these varieties was
tested on plots in which aldicarb
(Temik?) was used and on plots where no
nematicide was used. Each soybean vari-
ety was also planted in plots that had a
rotation crop before it and on others that
were previously planted to soybeans.
The test site was near Elberta in Baldwin
County in an area heavily infested with
root-knot and Race 4 cyst nematodes.
In plots where sorghum was
grown the previous year, Temik did not
increase yields of any of the seven varie-
ties tested. In the continuous soybean
plots, Temik increased yields in Centen-
nial, Kirby, Leflore, and Gordon varie-
ties. Yields in the soybean-sorghum rota-
tion versus continuous soybeans in-
creased by as much as 231 percent for
Stonewall and as little as 31 percent for
Kirby. The average increase from the
sorghum rotation was 85 percent.
In plots where American joint
vetch was grown,Temik increased yields
YWIYI~I IV LY( I YYI WIIY WVII ~- W ~~YII U)I~~UY I I A lLL IIII . I A ~1 II
in Centennial and Kirby. In continuous
soybeans only Braxton yields were im-
proved by using Temik. Yield responses
to the joint vetch rotation versus continu-
ous soybeans averaged 46 percent, rang-
ing from a low of 13 percent for Leflore to
a high of 105 percent for Stonewall.
In plots where hairy indigo was
grown, Temik increased yield in Kirby
soybeans, but only in the monoculture
system. Yield increases in rotation versus
continuous soybean plots ranged from a
low of 17 percent for Leflore to a high of
COMPUTERIZED PEST CONTROL
SAVES PRODUCTION COST
AUSIMM, Auburn University
Soybean Integrated Management Model,
was developed in the mid-1980s and field
tested in 40 grower fields in 1986-87. In
about 70 percent of the fields, net profits
were increased and risks decreased by
using the AAES-developed computer
model.
The model begins with a file that
contains approximately 120 soybean va-
rieties, ranked by maturity groups, rela-
tive productivity, and susceptibility to
nematodes and diseases. Potential yields
of the various varieties are calculated
given the location, soil type, planting
date, rotation, and pest histories of the
field.
AUSIMM is a menu-driven pro-
gram written for IBM-PC and com-
patibles with at least 512K RAM and one
floppy disk drive. Since the program is
written for use by farmers with little or no
experience with computers, it was de-
signed to be menu-driven and difficult to
lock up. Data entered into the program
by farmers are easily obtainable, requir-
ing little sophisticated equipment.
The model manages nematodes
primarily by the recommendation of re-
sistant varieties. Equations relating soy-
bean yield to nematode numbers were
developed using data available from
nematicide and variety experiments con-
ducted during 1979-84. These equations
adjust the yield for the effects of the
nematode complex on each of the 120
cultivars. The program then ranks the
best cultivars for selection, or on occasion
recommends that soybeans not be
planted.
210 percent for Braxton. The average im-
provement with hairy indigo over con-
tinuous soybeans was 55 percent.
In all the plots, Temik was ap-
plied at therate of 2 pounds of active
ingredient per acre in an 8-inch band.
Included in the test was Stonewall, a new
release from the Alabama Agricultural
Experiment Station; Braxton; Kirby;
Leflore; Gordon; Ransom; and Centen-
nial.
David B. Weaver, R. Rodriguez-Kabana,
and Emmett L. Carden
AUSIMM also includes a mid-
season foliar disease module that helps
growers determine whether fungicides
are needed, are economically justified,
and, if so, which materials to use. Fungi-
cides are cataloged for therapeutic activ-
ity, protection period, and application
cost. When a decision is made concerning
fungicide selection and application, the
projected yield and crop values in the
core program are updated.
The insect module with AU-
SIMM calculates the profitability of in-
secticide applications for one to several
soybean insect pests. It includes a soy-
bean plant growth model, along with
equations for temperature-dependent
development and feeding, sampling in-
formation, and insecticide-induced mor-
tality data. The value of the yield pro-
jected by each management choice is cal-
culated by subtracting application costs
from the market value of the yield pro-
jected by that choice. A display compar-
ing pest management decisions allows
the user to easily determine which are the
most profitable.
Comparisons of management
practices recommended by AUSIMM to
those actually made by farmers in 40
fields showed that the model saved farm-
ers money or increased profit 71 percent
of the time. Net return increases were
primarily due to decreased pesticide
costs, more timely pesticide applications,
and the careful selection of soybean va-
rieties. Extensive field tests in 1987 indi-
cate that the disease, insect, and nema-
tode submodels all had less risk associ-
ated with their decisions than the alterna-
tive management practices employed for
comparison, and that proper use of the
program improved soybean profitability
and decreased risk.
Tim Mack, Paul Backman,
and R. Rodriguez-Kabana
STUNTING VS. KILLING CUTS
WEED MANAGEMENT COSTS
Sicklepod is one of the most
troublesome weeds for southeastern
soybeans. Its tolerance to commonly
used herbicides and its adaptability to a
wide range of soil fertility and pH condi-
tions have allowed it to spread in the
South, particularly in Alabama.
While the cost of weed control
has not decreased, AAES research may
have identified a way to reduce this ex-
pensethrough herbicide management. A
single application of the herbicides Clas-
sic? or Scepter? was found to stunt sick-
lepod and other weeds enough to allow
growers to produce good yields at re-
duced herbicide costs.
Experiments at the Prattville
Experiment Field during the 1986 and
1987 growing seasons evaluated the com-
petitiveness of stunted sicklepod with
soybeans. Classic and Scepter herbicides
were used along with sicklepod densities
of 0, 2,4,6, and 8 plants per 3 feet of row.
Weed densities were established within 4
inches of the drill on the center row of a
three-row plot planted on 36-inch row
spacings. Classic was applied at 0.008
and Scepter at 0.125 pound of active in-
gredient per acre 16 days after planting
the soybeans. At that time, sicklepod
plants were about 1-4 inches tall.
Sickelpod dry weight was af-
fected by densities and herbicides. Clas-
sic reduced sicklepod dry weight as
much as 81 percent and Scepter reduced
it as much as 61 percent. Soybean yield
decreased as sicklepod density increased
up to six plants per 3 feet of row. In 1986,
soybeans in plots treated with Classic
yielded 43 percent more than untreated
plots and Scepter-treated plots yielded 26
percent more. In 1987, however, Classic
improved yields only 15 percent while
Scepter increased yields 23 percent.
Results indicated that a single
application of Scepter or Classic at the
recommended rate sufficiently stunted
sicklepod to reduce its competitiveness
with soybeans. These single applications
also reduced seed pod formation in sick-
lepod.
Planting soybeans in nar-
rower row spacings may offer chances to
further reduce competition of stunted
sicklepod and these practices may elimi-
nate the need for a second, expensive
herbicide application.
R. Harold Walker
I ~jlVrVIII ICIILIR IILLI~C13~U J1~1~ 11I ~L\IIVJ I 1~I\Y~11III~
r T~~~ I1 I 1 I I
RESISTANT SOYBEAN LOOPER
TOUGH TO CONTROL
The soybean looper is usually a
late season pest of soybeans in Alabama.
This insect reduces yield by eating leaves
needed to produce the sugars used by the
plant to grow seeds. Population out-
breaks of this insect can be rapid, because
soybean looper adults can migrate into a
field and lay a large number of eggs in a
short time.
Damaging
populations of this in-
sect are usually con-
trolled by the use of in-
secticides. However,
soybean looper larvae
that were resistant to
commonly used insecti-
cides were reported in
1988 in Louisiana, Mis-
sissippi, and Alabama.
Ambush? has been con-
sidered to be one of the
best, if not the best, in-
secticides to use against
this insect. However, it
was not effective in re-
ducing the population of
INOCULATION STILL IMPORTANT
IN SOME SOYBEAN FIELDS
In the 1960s and 1970s, when large
acreages of soybeans were planted on
land that had never grown soybeans be-
fore, producers and researchers found
that inoculation of soil with
Bradyrhizobium japonicum, the bacteria
that facilitates nitrogen fixation by soy-
beans, is critical. AAES research suggests
that inoculation is still important in land
that has never supported soybeans or has
not been used for soybean production for
several years.
Successful inoculation of soy-
beans on rhizobia-free land allows the
rhizobia to become "naturalized citi-
zens" that will persist for years after the
soybeans are harvested. Usually rhizo-
bia survival even 3 to 5 years after soy-
beans is adequate for replanting without
inoculation. In fact, soybeans in soils
with "naturalized" rhizobium popula-
tions seldom show yield responses to ad-
ditional inoculation.
Inoculants providing less than
1,000 rhizobia per seed were found to be
resistant soybean looper larvae in 1988
AAES research, see table.
Ambush at twice the normal
rate of 0.10 pound active ingredient pro-
vided only 1 percent control. The only
insecticide that provided more than 60
percent control was Danitol?, which is
currently not registered for use in soy-
beans. The mixture of Dimilin? plus
Dipel? was the best treatment that is reg-
istered for use, but it provided only 53
percent control.
Tim Mack
useless in inoculating soybeans. The best
inoculants provided 100,000 to one mil-
lion rhizobia per seed. Mixing inoculants
with seed treatment chemicals such as
fungicides or molybdenum salts was
found to be incompatible with bacteria
survival.
Soil measurements have shown
that a million or more rhizobia can be
found in a gram of soil taken from the
plow layer after soybeans are harvested.
Even after a corn-cotton rotation with
soybeans, more than 10,000 rhizobia per
gram of soil remain into the third year of
the rotation.
The only situation that criti-
cally reduces rhizobium levels is severe
soil acidity (pH 5). Under these condi-
tions, rhizobia are killed to near extinc-
tion within a few months after soybean
harvest. However, adding adequate lime
and a good inoculant with the next plant-
ing of soybeans was found to correct this
problem.
Art Hiltbold
,II
with or without sludge applications.)
Mean No. Total Soybean Loopers Per 6 Feet of Row
Number of loopers
Treatment, 
a.i./acre
Pretreatment Day 5 Day 7
Control.............................. 11.78 9.33 9.11
Ambush 2E, 0.20 Ib ............... 10.17 8.83 9.00
Ambush 2E, 0.25 lb................. 6.89 6.67 6.00
Ambush 2E, 0.20 lb.
+ PBO (1:8)...........................7.83 6.50 6.42
Scout Xtra 0.9E, 0.0188 Ib.....10.58 6.50 9.50
Danitol 2.4EC, 0.30 Ib ............ 10.75 3.08 2.58
Karate IE, 0.04 lb .................... 7.83 7.83 7.83
Dimilin 25W, 0.25 Ib ................ 9.58 8.42 8.33
Dimilin 25W, 0.25 lb.
+ Dipel ES, 12 BIU ................ 9.08 3.75 4.25
I , ~ '~ I I reatrnenr. a.l./acre
I ~ ~ . I I
IMPROVED VARIETIES FROM
AAES DEVELOPMENT
A soybean variety develop-
ment program was initiated by the
AAES in 1981 with the objective of de-
veloping superior cultivars suited for
Alabama growing conditions. Each year
since, thousands of experimental soy-
bean genotypes have been evaluated for
yield, pest resistance, and agronomic
characteristics at the Plant Breeding Unit
in Tallassee. Lines exhibiting superior
performance are advanced to statewide
tests and those that perform well in the
statewide tests are tested through a coop-
erative USDA testing program through-
out the Southeast.
This research yielded its first
release in 1988 (Stonewall), a mid-matur-
ity group VII variety that has excellent
yielding ability. In 12 Alabama tests dur-
ing 1985-87, it yielded 11 percent and 14
percent more than Braxton and Centen-
nial, respectively. In the USDA tests at 66
locations across the Southeast from 1986
to 1988, Stonewall yielded 7 percent more
than Thomas and 10 percent more than
Braxton.
Stonewall is resistant to race 3
of soybean cyst nematode, stem canker,
and frogeye leafspot, and tolerant to
lance nematodes and Phytophthora root
rot. Protein and oil content, seed quality,
lodging, plant height, and seed size are
equal or superior to other adapted varie-
ties.
Approximately 750 bushels of
Stonewall Foundation seed were pro-
duced in 1988. Seed should be available
on a limited basis for general production
by 1990. More promising lines are in
various stages of development, with
other releases anticipated.
David B. Weaver
and R. Rodriguez-Kabana
APPLYING PAPER MILL SLUDGE
IMPROVES SOIL FERTILITY
Applying paper mill sludge to
soil increased soil fertility, organic mat-
ter, and pH in tests at the Lower Coastal
Plain Substation, Camden. However,
soybean yields were not affected by the
sludge applications during the 3 years of
the test. (Yields averaged 32, 26, and 32
bushels per acre in 1986, 1987, and 1988
Three application 
rates were 
These results in-
tried: 10, 30, and 60 tons per acre. At the dicate that paper mill 
Soilfactor Soil content, by sludge rate/acre
60-ton rate, the sludge contained 194 sludge may be an excel- None 30 tons 60 tons
pounds of nitrogen, 92 pounds 
of phos- lent alternative 
to agricul-
phorus, 218 pounds of potassium, 5,916 tural limestone on sandy Phosphorus, lb./acre 
.............. 87 95 98
pounds of calcium, 271 pounds of magne- Coastal Plain soils. Fur- Potassium, lb./acre ....... 142 156 158
sium, and the equivalent of 6.7 tons of thermore, such use would 
Calcium, lb./acre...............1,037 1,847 2,577
limestone. Increases in soil fertility after 
offer an economical alter- Magnesium, lb./acre 
............. 155 163 182
the first year's application are indicated native to landfill disposal o pH....... .......... 6.8 7.3 7.5
by the soil 
content figures 
given in 
the for 
the pulp and 
paper in-
table for different sludge rates. dustry.1
G.L. Mullins, J.W. Odom, and D.C. Burrows
SOYBEAN VARIETIES
FOR 1989
Soybean varieties that have per-
formed best in AAES variety tests for 3
years or longer are listed below for each
region of Alabama. Varieties are
grouped according to maturity, and are
listed in alphabetical order. Detailed
results of variety performance are re-
ported in the current year's soybean vari-
ety report.
Northern Alabama
Full season
Bradley
Centennial 126
Coker RA 606
Coker 686
Hartz H 6130
Jeff
Leflore
New NK S69-54
Pioneer 9691
Tracy M
Late
Braxton
Hartz H 7126
Ransom
Terra-Vig 708
March 1989 10M
Pioneer.. ......... b
Central Alabama
Very early
Asgrow A 5980
Coker 485
Deltapine 105
Forrest
Hartz H 5370
Terra-Vig 515
Early
Asgrow A 6785
Coker RA 606
Coker RA 680
Davis
FFR 668
Leflore
Pioneer 9691
Tracy M
Young
Full season
Braxton
Coker 6727
FFR 771
GaSoy 17
Hartz H 7126
New NK S72-60
Terra-Vig 708
Terra-Vig 717
Wright
Late
Cobb
Coker 368
Dowling
Foster
Black Belt (acid soil)
Very early
Ba
Deltapine 105
Hartz H 5370
Wilstar 550
Early
Centennial
Coker RA 680
Davis
Deltapine 566
Hartz H 6130
Leflore
Tracy M
Full season
Braxton
Deltapine 417
Hartz H 7126
Ransom
Late
Cobb
Coker 368
Dowling
Johnston*
Southern Alabama
Very early
Deltapine 105
Pioneer 9591*
Early
Coker RA 606
Coker RA 680
Davis
Jeff
Leflore
New Nk S69-54
Terra-Vig 616
Tracy M
Full season
Braxton
Coker 6727
Coker 6847
Deltapine 417
GaSoy 17
Hartz H 7126
Pioneer 9791
Stonewall
(Au82-204)
Terra-Vig 717
Late
Cobb
Coker 368
Coker 6738
Dowling
Johnston
Kirby
Baldwin-Mobile
Very early
Deltapine 105
Forrest
Early
Davis
Hartz H 6130
Jeff
Leflore
New NK S69-54
Twiggs
*Based on 2-year data.
Alabama Agricultural Experiment Station
Auburn University
Au .urn Univesity, Alabama 36849-0520
......... .... .....
........................... ........
Full season
Braxton
Coker 6727
Coker 6847
Hartz H 7126
New NK S72-60
Pioneer 9791
Stonewall
(Au82-204)
Terra-Vig 708
Wright
Full season, late
Cobb
Coker 368
Coker 6738
Dowling
Hartz Hf 8112
Johnston
Kirby
NON-PRorT ORG.
PSAE& FEESPAI
PERMIT.N.9
AUBURN,....... ALA.. ......
Early
Asgrow A 5980
Bay
Bedford
Coker 425
Coker 485
Deltapine 105
Deltapine 415
Essex
FFR 561
Hartz H 5164
Hartz H 5171
Hartz H 5370
Pioneer 9591
Terra-Vig 515
Terra-Vig 553
EDITOR'S NOTE.
Mention of company or trade names does
not indicate endorsement by the Alabama
Agricultural Experiment Station or Au-
burn University of one brand over another.
Any mention of non-label uses or applica-
tions in excess of labeled rates of pesticides
does not constitute a recommendation.
Such use in research is simply part of the
scientific investigation necessary to fully
evaluate materials and treatments.
-.-. ---- .- -----------... ...... ... . . . . . . . . . . . . .... ... .. . . . . . . . . . . . . .. . . . . . . . .. . . . .. . .