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FRUIT PPR
Performance of 'Apache' Blackberry in South Alabama ................................................................. 3
A Promising New Surfactant for Thinning Peach Blossoms, 2001 ....................................................... 4
Results of Peach Blossom Treated with Tergitol.TM7N-6, 2002 .......................................................... 4
Refined Applications Rates for Tergitol TMN-6 for Blossom Removal of Peach....................................... 5
Extending the Time of Application for Chemically Thinning Peach....................................................... 6
Evaluation of Flint and Elite for Brown Rot Control on Peaches ......................................................... 7
Evaluation of Sulfur-Based Fungicides for Scab Control on Peaches.................................................... 8
Evaluation of Captan/Sulfur Tank Mixes for Peach Scab and Brown Rot Control on Peaches ........................ 9
Evaluation of Ziram 76 DF for Red Spot Control on Peaches, 2002.................................................... 10
Screening of New Insecticides for Control of Plum Curculio in Peaches .............................................. 10
Frequency of Warm Winters Increases Need for Rest-Breaking Compounds......................................... 12
Effects of the Rate of Nitrogen and Times of Pruning on Three Varieties of Peach
in Central Alabama, 2001 ............................................................. . . ..... 0...*... ...00..0...13
Effects of the Rate of Nitrogen and Times of Pruning on Three Varieties of Peach
in Central Alabama, 2002 .......................................................................................... 14
Efficacy of the Soil Fumigants Telone C-35 and Telone 11 on Growth and Survival
of Peach Trees on a Replant Site....................................................................... 0........0. 16
Evaluation of Fungicide Spray Programs for Pecan Scab Control ...................................................... 17
Alternate Bearing in Satsumas ............................................................................................. 18
Satsuma Disease Survey of Alabama.................................................................................... 18
Evaluation of Fungicides for Botrytis Gray Mold Control on Strawberries, 2002 ...................................... 19
VEGETABLE PAPERS
Evaluation of Fungicides for Control of Alternaria Leaf Spot of Cabbage.............................................. 21
Effect of Nitrogen Source on Quality and Yield of 'LaRouge' Irish Potato............................................ 21
Effect of Split Application of Desiccant and Vine Rolling on Quality and Yield
of 'LaRouge' Irish Potato .............................................................. 22
Evaluation of Synthetic and Biological Fungicides for Control of Powdery Mildew on Pumpkin........... s.e... 23
Evaluation of 1PM Spray Programs for Control of Foliar Diseases of Pumpkin, 2001 ....... ....... 24
Comparison of TerraPy G and TerraPy B to Methyl Bromide as Growth Promoters
for Tomato, 2001................................................................................................. 25
Evaluation of TerraPy G at Multiple Rates as a Growth Promotion for Tomato,
North Alabama, 2001............................................................................................... 26
Evaluation of TerraPy G at Multiple Rates as a Growth Promotion for Tomato,
SadMuti,201................................7
Robert Boozer
Area Horticulturist
Chilton Area Horticulture Station
S.L. Burchett
Graduate Research Assistant
Department of Horticulture
Jason Burkett
Superintendent-Horticulture Unit
E. V. Smith Research Center
Arnold Caylor
Superintendent
North Alabama Horticulture Station
Tony Dawkins
Superintendent
Sand Mountain Research and Extension Center
William Dozier
Professor
Department of Horticulture
Robert Ebel
Co-editor
Associate Professor
Department of Horticulture
Wheeler Foshee
Extension Program Associate
Dept. of Entomology and Plant Pathology
Dan Horton
Professor and Extension Entomologist
University of Georgia
Joseph Kemble
Co-editor
Associate Professor and Extension Horticulturist
Department of Horticulture
Joseph W. Kloepper
Professor
Department of Entomology and Plant Pathology
Ron McDaniel
Superintendent
Gulf Coast Research and Extension Center
Kathy McLean
Associate Professor
Dept. of Entomology and Plant Pathology
John F. Murphy
Associate Professor
Dept. of Entomology and Plant Pathology
Monte Nesbitt
Area Horticulturist
Gulf Coast Research and Extension Center
Malcomb Pegues
Assistant Superintendent
Gulf Coast Research and Extension Center
Jim A. Pitts
Superintendent
Chilton Area Horticulture Station
M.S. Reddy
Professor
Alabama A&M University
Jeff Sibley
Associate Professor
Department of Horticulture
Clifford Sikora
Edward Sikora
Associate Professor and Extension Plant Pathologist
Department of Horticulture
Johnny Staples
Raymond Thomas
Graduate Research Assistant
Department of Horticulture
Edgar Vinson
Research Assistant
Department of Horticulture
Bryan Wilkins
Graduate Research Assistant
Department of Horticulture
Floyd M. Woods
Associate Professor
Department of Horticulture
AUTHORS
FRUIT PAPERS
PERFORMANCE OF 'APACHE' BLACKBERRY IN SOUTH ALABAMA
Monte Nesbitt, Ron McDaniel, and Malcomb Pegues
Six cultivars of thornless blackberries are being evaluated 'A
at the Gulf Coast Research and Extension Center in Fairhope, based or
Alabama. Cultivars being studied include 'Apache', 'Arapaho', 'Apache
'Chester', 'Loch Ness', 'Navaho', and 'Triple Crown'. Details of 2001, it c
the planting and results from the first harvest were described in have exc
the 2000 Fruit and Vegetable Research Report. No data were than sor
presented for 'Apache' in the 2000 report because it was planted sive tha
in midsummer 1999 and did not bear fruit until 2001. taste is c
'Apache' was released in 1999 by the University ofArkan- and is be
sas, as a large-fruiting, thornless cultivar with resistance to or- quicklye
ange rust disease. Orange rust has been found on three plants of vantage.
'Navaho' in this trial, and one plant of 'Arapaho', but has not later tha
been detected on 'Apache', 'Chester', 'Loch Ness', or 'Triple tinuing i
Crown'. No double-blossom disease has been detected to date Th
in the entire planting, but minor cane and leaf damage has been a problei
caused by Cercospora and Colletotrichum fungi. was 850
YIELD OF SELECTED BLACKBERRY CULTIVARS
Cultivar Fruit Berries Berries Pints Harvest
(Ibs/plant) (no/Ib) (no/pt) (no/plant) period
2001
Apache 4.1 62 43 6 5/23-7/27
Arapaho 5.8 107 73 9 5/14-6/22
Navaho 6 103 74 8 5/21-7/11
2002
Apache 10 67 46 14 6/7-7/31
Arapaho 5.3 133 94 8 5/24-6/26
Navaho 3.7 107 80 5 5/30-7/31
1 Taste score 1-5, 5=best.
Spache' was the best performing cultivar in 2001 and 2002,
n yield and fruit size data (see table). Although yield of
' was slightly lower than 'Arapaho' and 'Navaho' in
Slearly out-yielded either cultivar in 2002. Fruit of 'Apache'
oellent eye appeal and size. While the size is still smaller
ie thorny cultivars like 'Kiowa', it is much more impres-
n the other thornless cultivars in this trial. Flavor and
omparable to 'Navaho', 'Arapaho', and 'Triple Crown',
tter than 'Chester' and 'Loch Ness'. 'Apache' fruit soften
after harvest, and shelf-life is limited, which is one disad-
'Apache' has a harvest period similar to 'Navaho' and
n 'Arapaho', beginning in late May or early June, con-
into late July, and peaking in late June.
iere was some concern that insufficient chilling might be
m on the Gulf Coast. Chill hour accumulation at Fairhope
in 2000-01 and 700 in 2001-02, but the high production of
'Apache' in 2002 would sug-
gest that its chill hour require-
ment is not higher than 700
Taste Maximum hours. 
While continued
evaluation is planned, it ap-
pears that 'Apache',
S 3.1 11.2 
'Arapaho', and perhaps 
'Na-
S 3.4 11.5 vaho', have 
some merit for the
L 3 12.2 Gulf Coast. We see no poten-
tial in 'Chester', 'Loch Ness',
or 'Triple Crown' as cultivars
3.4 12.9 
for South Alabama.
3.5 14
L 3.1 14
A PROMISING NEW SURFACTANT FOR THINNING PEACH BLOSSOMs, 2001
Bryan Wilkins, Robert Ebel, Jim A. Pitts, and Robert Boozer
Peach trees are prolific fruit producers and set more fruit
than the tree can support. Trees must be thinned to have fruit
that are of acceptable size for market. Thinning is usually done by
hand, which is very costly and time consuming.
In the late 80s and early 90s researchers at Auburn Univer-
sity worked with several different chemicals to try and find an
effective bloom thinner. Surfactant WK proved to be very prom-
ising. Researchers were able to determine that the active ingredi-
ent was Tergitol TMN-6 or Tergitol TMN-10.
In 2000, Tergitol TMN-6 and Tergitol TMN-10 were tested
at two rates, 2% and 4%, and at two stages of bloom develop-
ment, full bloom and petal fall.
Both chemicals thinned effec-
tively and had no adverse ef-
fects on fruit quality. How-
ever, the 4% rate at petal fall
defoliated trees and was omit-
ted in future tests.
In 2001, only Tergitol
TMN-6 was tested at varying
rates. The study was ar-
ranged as a randomized com-
plete block design with seven
treatments and five replica-
tions in single tree plots with
a buffer tree between each
treatment tree and a buffer
row between each treatment
row. Trees were sprayed at
90% full bloom and at petal fall with concentrations of either 0%,
1%, 2%, or 3%. Bloom counts were taken before spraying and
fruit counts were taken before hand thinning. All normal com-
mercial practices were followed in regards to harvest.
Time of application did not alter thinning but thinning
early did increase fruit size at hand thinning (see table). Thin-
ning with the chemical did not adversely affect fruit quality. The
extent of thinning correlated with the rate of chemical applied.
Fruit quality was not adversely affected by the chemical. Tergitol
TMN-6 effectively thinned peach blossoms without adverse ef-
fects on the tree or fruit.
FLOWER REMOVAL AND FRUIT GROWTH OF PEACHES
TREATED WITH TERGITOL TMN-6, 2001
Fruit -Fruit hand thinned- Total fruit Fruit
set weight number harvested Yield weight
(%) (g/fruit) (no/tree) (no/tree) (Ibs/tree) (g)
Concentration (%)
0 46.0 a' 16.2 c 1416 a 713 a 186 127 d
1 37.0 b 18.8 b 686 b 689 ab 213 144 c
2 23.0 c 20.8 b 456 bc 490 bc 180 167 b
3 9.0 d 24.3 a 138 c 347 c 149 192 a
Time of application
Control 46 a 16 b 1416 a 713 a 84 127 b
Full bloom 22 b 22 a 348 b 424 b 71 171 a
Petal fall 24 b 21a 506 b 594 ab 93 165 a
SMeans separation within columns by Duncan's Multiple Range Test p = 0.05; columns without
letters are not significantly different.
RESULTS OF PEACH BLOSSOM TREATED WITH TERGITOL TMN-6, 2002
Bryan Wilkins, Robert Ebel, Jim A. Pitts, and Robert Boozer
This is a continuation of a study that was initiated in 2000
at the Chilton Research and Extension Center in Clanton, Ala-
bama, to test the efficacy of two surfactants as peach blossom
thinners.
In 2002, the study was repeated using the same rates and
application times as in 2001 [ 0% (control), 1%, 2%, and 3% con-
centrations at full bloom and petal fall]. The experimental design
consisted of five blocks with single trees treated within each
block. There were buffer trees between treated trees within each
row and buffer rows between treated rows to reduce contamina-
tion by spray drift. Five limbs that were 12 to 18 inches long were
tagged on each data tree and the number of flowers were counted
and classified according to stage of development. The treatments
were applied using an airblast sprayer. All normal commercial
practices were followed after treatment. Data collected included
pretreatment flower counts, pre-hand thinning fruit counts on
data limbs to determine fruit set, and number of fruit hand thinned
per tree.
There were no significant differences in fruit weight at
hand thinning and the number of fruit hand thinned per tree (see
table). Amount of thinning did increase slightly with increasing
chemical rate. There were no significant differences in time of
application. There were no adverse effects on harvest or fruit
quality at harvest by the chemical. These results do not reflect
previous work with this chemical nor are there any 
apparent
reasons for these differences from previous studies.
ALABAMAAGRICULTURAL ExPERIMENT STATION4
2001-2002 FRUIT AND VEGETABLE RESEARCH REPORT 5
FLOWER REMOVAL AND FRUIT GROWTH OF 'FIREPRINCE' PEACH TREES
TREATED WITH TERGITOL TMN-6, 2002
Fruit -Fruit hand thinned- Total fruit Fruit
set weight number harvested Yield weight
Concentration (%) (g/fruit) (no/tree) (no/tree) 
(lbs/tree) (g)
0 60.0 a' 12.8 356 548 163 143
1 61.0 a 12.9 368 698 187 135
2 54.0 a 14.2 337 590 161 145
3 40.0 b 14.0 328 689 255 167
Time of application
Control 59 13 712 548 74 143
Full bloom 53 13 779 713 94 145
Petal fall 51 14 597 605 89 154
Means separation within columns by Duncan's Multiple Range Test p = 0.05; columns without
letters are not significantly different.
EFINED APLICATION RATES FOR TERGITOL TMN-6
FOR BLOSSOM REMOVAL OF PEACH
Bryan Wilkins, Robert Ebel, Jim A. Pitts, and Robert Boozer
In previous experiments, Tergitol TMN-6 was effective in
thinning peach blossoms; however, the rates that have been
tested-1%, 2%, 3%, and 4% by volume-have either not re-
moved enough of the flowers, (1%), or have removed too many
flowers, (2%, 3%, and 4%). The objective of this experiment was
to determine the most effective rate of Tergitol TMN-6 on the
thinning of peach.
This study was initiated in the spring of 2002 at the Chilton
Research and Extension Center in Clanton, Alabama. Three trees
of 'Sunland' peach were sprayed at petal fall with rates of 0%
(control), 1%, 1.5%, and 2% by volume Tergitol TMN-6 with an
airblast sprayer. The center tree of the three was used as the data
tree and an unsprayed buffer tree was between each plot with a
buffer row between treated rows. Four limbs 1 to 2 feet in length
were selected on each treatment tree and the total flower count and
the stage of physiological development were determined prior to
treatment. Before hand thinning, the number of fruit on each tagged
limb was counted to determine fruit set. A drop cloth was placed
under one half of the tree at time of hand thinning and the fruit
collected to determine the number of fruit hand thinned per tree.
Fruit were harvested according to normal commercial practices.
There were no significant differences in fruit set or fruit
weight at hand thinning; however, there was a trend towards
decreased fruit number that required hand thinning with increased
rate of Tergitol (see table). There were no adverse effects on
harvest or fruit quality.
FLOWER REMOVAL AND FRUIT GROWTH OF 'SUNLAND' PEACH TREES
TREATED WITH TERGITOL TMN-6, 2002
Fruit -Fruit hand thinned- Total fruit Fruit
set weight number harvested Yield weight
(%) (g/fruit) (no/tree) (no/tree) (lbs/tree) (g)
Concentration (%)
0.0 491 13.0 504 282 79 129 c
1.0 52 12.6 472 249 79 146 a
1.5 46 13.5 442 290 82 132 b
2.0 41 13.8 346 204 63 142 ab
1 Means separation within columns by Duncan's Multiple Range Test p = 0.05; columns without
letters are not significantly different.
6 ALABAMA AGRICULTURAL EXPERIMENT STATION
ErENDING THE TIME OF APPLICATION
FOR CHEMIALLY THINNING PEACH
Bryan Wilkins, Robert Ebel, Jim A. Pitts, and Robert Boozer
Peach trees set more fruit than the tree is able to support.
Therefore, to have fruit that is of acceptable market size, up to
95% of the fruit must be removed from the tree. This is a very
costly and time consuming process that is done primarily by
hand. Currently no acceptable chemical thinners are available.
The chemicals that are available are not consistent from year to
year and the results from their applications cannot be seen for
several weeks. These chemicals must also be applied within a
very narrow application window to be effective. In a previous
study conducted at the Chilton Research and Extension Center
in Clanton, Alabama, Tergitol TMN-6 was shown to be an effec-
tive blossom thinner of peach that could be applied at full bloom
and petal fall and still provide adequate thinning.
In the spring of 2002, a study was initiated with the objec-
tive of determining the effect of Tergitol TMN-6 after petal fall on
the blossom thinning of peach. Tergitol TMN-6 was applied to
'Harvester' peach at four dif-
ferent stages of blossom de-
velopment (full bloom, petal
fall, shuck split, and shuck off)
at rates of 0% (control), 1%,
2%, and 3% by volume with an
airblast sprayer. The experi-
mental plot was a randomized
complete block design with
single treatment trees with a
buffer tree between treatment
trees and a buffer row between
treatment rows to minimize
drift. Four limbs 1 to 2 feet 
in
length were selected on each
treatment tree and the total
flower count and the stage of
physiological development
were determined prior to treat-
ment. Before hand thinning, the
number of fruit on each tagged limb were counted to determine
fruit set. A drop cloth was placed under one half of the tree at
hand thinning and the fruit collected to determine the number of
fruit hand thinned per tree. Fruit were harvested according to
normal commercial practices.
Time of application had no affect on the amount of thin-
ning, but thinning early did increase fruit size at hand thinning
(see table). The amount of thinning increased with the increasing
chemical concentration. Some damage occurred to fruit when the
chemical was applied after petal fall, with the two highest rates
having the most damaged fruit. Also the foliage was severely
burned, and at the two highest rates the trees at shuck split were
heavily defoliated. Due to concerns about phytotoxicity, the
shuck off treatment was not applied. The highest rates had the
fewest number of fruit and the lowest yield. There were no ad-
verse effects on fruit quality.
FLOWER REMOVAL AND FRUIT GROWTH OF 'HARVESTER' PEACH TREES
TREATED WITH TERGITOL TMN-6, 2002
Fruit -Fruit hand thinned- Scarred Total fruit Fruit
set weight number fruit harvested Yield weight
(%) (g/fruit) (no/tree) (%) (no/tree) (lbs/tree) (g)
Concentration (%)
0 39 a' 11.6 3548 a 0 c 705 124 90
1 41 a 14.6 2251 b 2 bc 523 131 120
2 36 ab 15.5 1620 bc 12 ab 425 111 126
3 29 b 15.8 1472 c 16 a 411 108 124
Time of application
Control 39 11.6 b 3548 0 b 705 124 90
Full bloom 32 16.3 a 1787 0 b 453 120 127
Petal fall 39 15.3 a 1977 1 b 471 121 125
Shuck split 35 14.3 a 1579 28 a 434 109 119
1 Means separation within columns by Duncan's Multiple Range Test p = 0.05; columns without
letters are not significantly different.
2001-2002 FRUIT AND VEGETABLE RESEARCH REPORT 7
EVALUATION OF FLINT AND ELITE
FOR BROWN RoT CONTROL ON PEACH
Edward Sikora, Jim A. Pitts, Robert Boozer, and Clifford Sikora
This test was conducted to evaluate fungicides targeted
for use in the preharvest period for control of brown rot. The
fungicides Elite and Flint were evaluated at various rates indi-
vidually, and as tank-mix partners. Results showed no differ-
ences in brown rot control among the treatments though all were
more effective than the unsprayed control treatment. These fun-
gicides did not appear to have a beneficial effect in controlling
Rhizopus rot, another postharvest disease of peaches.
The experiment was conducted on a block of 'Harvester'
peach trees at the Chilton Research and Extension Center in
Clanton, Alabama. The experiment consisted of eight treatments,
replicated five times, in a randomized complete block design.
Treatments consisted of preharvest spray programs that com-
pared Elite, Flint, or tank mixes of the two products in various
combinations. All trees were maintained during the bloom and
cover period following commercial production practices typical
for the area. All trees were sprayed with Captan 50 WP at 5 pounds
per acre on March 13, and with Captan 50 WP 3 pounds per acre
plus sulfur 80% at 5.5 pounds per acre on March 22, April 2, April
6, April 20, May 4, and May 14. Preharvest treatments were ap-
plied on June 4, June 7, June 11, and June 13. The station super-
intendent decided on the closely spaced application schedule,
which he felt was necessary as he suspected the fungicides did
not have a sufficient time to dry on the fruit before heavy rains
prevailed shortly after the fungicides were applied.
TABLE 1. PERCENT BROWN ROT AND RHIzoPus ROT
No symptoms of brown rot or any signs of phytotoxicity
were observed on trees one day prior to the first harvest date. A
total of 40 fruit per plot was sub-sampled at harvest (June 14) and
stored in trays at approximately 75
0 
F for eight days. Percent fruit
with brown rot and Rhizopus rot was determined four and eight
days after the first harvest date.
A second harvest was conducted on June 18, five days
after the last fungicide application. A total of 20 fruit per plot were
sub-sampled on the second harvest date and stored in trays at
approximately 75
0
F for four days. Percent of fruit with brown rot
and Rhizopus rot was determined four days after the second
harvest (June 22), which was nine days after the final fungicide
application. Yield in pounds of marketable fruit was determined.
All the fungicide treatments had significantly less brown
rot than the unsprayed control at both four and eight days
postharvest (with the last fungicide application one day prior to
harvest) (Table 1). There were no significant differences in Rhizo-
pus rot among the treatments at either rating period.
All the fungicide treatments had significantly less brown
rot than the unsprayed control four days postharvest (with the
last fungicide application five days prior to harvest) (Table 2).
There were no significant differences in Rhizopus rot among the
treatments.
The Flint 50 WG treatment at 3 ounces per acre had the
highest yield, significantly higher than the two lower rates of
Elite treatments. In general,
yields were highest in the Flint-
FOUR AND EIGHT DAYS only treatments followed by the
POSTHARVEST'
-Four days postharvest- -Eight days postharvest-
Treatment Rate/acre Brown rot Rhizopus Brown rot Rhizopus
(%) (%) (%) (%)
Unsprayed control - 5.0 a 20.5 a 8.5 a
ELITE 45 WG 5 oz 0.0 b 0.5 a 0.0 b 9.5 a
w/t Induce 0.06%
ELITE 45 WG 6 oz 0.0 b 0.5 a 0.0 b 10.0 a
w/t Induce 0.06%
ELITE 45 WG 8 oz 0.0 b 1.0 a 0.0 b 9.5 a
w/t Induce 0.06%
FLINT 50 WG 2 oz 0.0 b 0.6 a 0.0 b 8.7 a
FLINT 50 WG 3 oz 1.5 b 1.5 a 1.5 b 9.5 a
ELITE 45 WG 2.9 oz 0.0 b 0.0 a 0.0 b 3.0 a
+
FLINT 50 WG 2.6 oz
ELITE 45 WG 3.5 oz 0.5 b 1.5 a 0.0 b 11.0 a
+
FLINT 50 WG 3.1 oz
1The last fungicide application was one day prior to harvest, 2001.
2 Numbers followed by the same letter are not significantly different.
Flint/Elite tank-mix treatments
and the Elite-only treatments.
8 ALABAMA AGRICULTURAL EXPERIMENT STATION
TABLE 2. PERCENT BROWN ROT AND RHIZOPUS ROT FOUR DAYS POSTHARVEST
-Four days postharvest-
Treatment Rate/acre Brown rot Rhizopus Yield
(%) (%) (lbs/plot)
Unsprayed control - 22.0 a
2  
8.0 a 141.4 ab
ELITE 45 WG 5 oz 0.0 b 3.6 ab 129.5 b
w/t Induce 0.06%
ELITE 45 WG 6 oz 0.0 b 5.0 ab 119.2 b
w/t Induce 0.06%
ELITE 45 WG 8 oz 0.0 b 0.0 b 140.1 ab
w/t Induce 0.06%
FLINT 50 WG 2 oz 0.0 b 2.2 ab 168.7 ab
FLINT 50 WG 3 oz 0.0 b 5.7 ab 205.1 a
ELITE 45 WG 2.9 oz 0.0 b 1.3 ab 162.0 ab
+
FLINT 50 WG 2.6 oz
ELITE 45 WG 3.5 oz 0.0 b 2.5 ab 181.5 ab
+
FLINT 50 WG 3.1 oz
1 The last fungicide application was five days prior to harvest, 2001.
2 Numbers followed the same letter 
are not significantly different.
EVALUATION OF SULFUR-BASED FUNGICIDES FOR SCAB CONTROL
oN PEACHES
Edward Sikora and Jim A. Pitts
Peach scab is a common fungal disease of peaches in Ala-
bama resulting in spotted and scarred fruit and reduced fruit
quality. This test was conducted to evaluate various cover spray
programs using Microthiol Disperss, a sulfur-based fungicide.
These programs were compared to the Alabama peach industry
control on peaches. Results from this study indicate that
Microthiol Disperss at rates from 6 to 10 pounds per acre and in
a tank-mix or rotational program with Captan 50 WP controlled
scab as well as Wettable sulfur at 9 pounds per acre. The
Microthiol Disperss/Captan tank-mix treatment and the Microthiol
Disperss/Captan rotation treatments also performed as well as
Captan 50 WP 5 pounds per acre in controlling scab.
This experiment was conducted at the Chilton Research
and Extension Center in Clanton, Alabama, in 2002. The test con-
sisted of seven treatments replicated five times in a randomized
complete block design. All treatments including the control re-
ceived two Bravo Weatherstik applications at petal fall and shuck
split and preharvest applications of Orbit at standard rates. There
EFFECT OF FUNGICIDE SPRAY PROGRAMS
ON SCAB INCIDENCE, CLANTON, 2002
Tratment
Treatment
rate per acre'
Unsprayed control
Microthiol Disperss 10 Ib
Microthiol Disperss 6 lb
Microthiol Disperss 3 lb +
Caotan 50 WP 3.0 Ib
Fruit with scab Marketable fruit
(%) (%)
37.5
3.5
5.0
0.5
81.5
98.5
98.5
100.0
Captan 50 WP 5.0 lb 0.5 100.0
rotated with
Microthiol Disperss
2
Wettable sulfur 90 WP 9 lb 4.5 100.0
Captan 50 WP 5 Ib 0.5 99.5
1 Each treatment received eight cover sprays.
2 Captan was used in cover sprays 1, 
3, 5, and 7 and Microthiol
Disperss was used in sprays 2, 4, 6, and 8.
2001-2002 FRUIT AND VEGETABLE RESEARCH REPORT
were a total of eight cover sprays applied for each treatment.
Forty fruit were collected from each two-tree replication at har-
vest and evaluated for incidence and marketability (disease se-
verity) of scab. Fruit were stored at 75
0
F for seven days then
rated for the postharvest fungal diseases brown rot and Rhizo-
pus rot.
All fungicide treatments performed significantly better than
the unsprayed control (see table). Scab incidence ranged from
9
0.5 to 5.0% among the fungicide treatments. Treatments that used
Captan 50 WP had slightly lower levels of scab incidence than
programs that used Microthiol Disperss or Wettable sulfur alone
full season. There were no significant differences among the
fungicide programs in fruit marketability, and all produced sig-
nificantly more marketable fruit than the unsprayed control. There
were no differences in brown rot or Rhizopus rot control among
the treatments, including the unsprayed control (data not shown).
EVALUATION OF CAPTAN/SULFUR TANK XES FOR PEACH SCAB AND
BROWN SPOT CONTROL ON PEACHES
Edward Sikora, Jim A. Pitts, Robert Boozer, and Clifford Sikora
Peach producers in Alabama commonly use sulfur as part
of their disease management program. To improve its effective-
ness, and to keep costs relatively low, some growers tank-mix
sulfur with the fungicide Captan for spraying during the cover
period. How effective this program is in controlling peach dis-
eases and the relative ratio of sulfur to Captan needed for control
are still not clear. This reports outlines the results of the third
year of a three-year study comparing two sulfur/Captan tank-mix
programs with the standard, full season cover spray programs of
sulfur or Captan alone.
The experiment was conducted at the Chilton Research
and Extension Center near Clanton, Alabama, on the cultivar
'Alred Alberta'. Treatments consisted of cover spray programs
of (1) unsprayed control, (2) Captan 50 WP at 5 pounds per acre,
(3) Sulfur 80% at 9 pounds per acre, (4) Captan 50 WP 3 pounds
per acre plus Sulfur 80% at 5.5 pounds per acre, and (5) Captan 50
WP 2 pounds per acre plus Sulfur 80% at 3.5 pounds per acre.
All the fungicide programs performed significantly better
than the unsprayed control in terms of scab incidence and mar-
ketability of fruit (see table). The sulfur-only program had a sig-
nificantly higher level of scab incidence compared to the Captan
and the Captan/sulfur tank-mix programs. The sulfur-only pro-
gram also produced significantly less marketable fruit than the
Captan program and the higher rate program of the Captan/sulfur
tank mix. Brown rot was a significant problem based on the high
level of disease incidence on the unsprayed control. There was
no significant difference in brown rot incidence among the fungi-
cide programs; however disease incidence was highest in the
sulfur-only program and progressively less with higher rates of
Captan. There were no significant differences in Rhizopus rot
among the treatments, including the unsprayed control.
Results from this trial are similar 
to what was observed in
1999. Spray programs consisting of Captan alone at 5 pounds per
acre or Captan 3 pounds per acre plus Sulfur at 5.5 pounds per
EVALUATION OF CAPTAN/SULFUR TANK MIXES FOR PEACH SCAB AND
BROWN ROT CONTROL ON PEACHES, 200.1
Fungicide cover Fruit Marketable Brown Rhizopus
spray program' with scab fruit rot rot
Unsprayed control 92.7 a
2  
16.2 c 65.6 a 18.4 a
Captan 50 WP 5 Ib/ac 5.7 c 96.8 a 8.8 b 23.9 a
Sulfur 80% 9 Ib/ac 31.3 b 84.1 b 19.2 b 28.6 a
Captan 50 WP 3 lb/ac + 5.0 c 98.0 a 11.6 b 264 a
Sulfur 80% 5.5 lb/ac
Captan 50 WP 2 Ib/ac + 17.5 c 91.2 ab 16.5 b 25.7 a
Sulfur 80% 3.5 lb/ac
Bravo Ultrex was applied atshuck split and petal-fall and two Orbit sprays were applied at seven
and one day before harvest for all treatments except the control. A total of 40 fruit were picked
from the center two trees of each treatment/replication. Percent of fruit with scab and percent
marketable fruit were determined at harvest. Incidence of brown rot and Rhizopus rot was deter-
mined seven days after harvest.
2Numbers followed by the same letter are not significantly 
different from one another.
acre had fewer fruit with scab
lesions and higher levels of
marketable fruit compared to
the sulfur-only program. In
the three-year study, the tank-
mix programs have usually
performed as well as the Cap-
tan-only program, though the
lower rate of the Captan/sul-
fur tank-mix program is less
effective in high scab pres-
sure situations. The Captan/
sulfur tank-mix programs and
the sulfur-only program may
also suffer from heavier losses
from brown rot in high brown
rot-pressure years, though
this needs to be investigated
further.
ALABAMA AGRICULTURAL EXPERIMENT STATION
E VALUATION OF ZiRm 76 DF FoR RED Sor CONTROL 
ON PEACHEs, 2002
Edward Sikora, Jim A. Pitts, Robert Boozer, and Wheeler Foshee
Red spot is a common problem in Chilton County on light-
skinned peaches. The cause of the disease is still unclear. One
report suggests red spot is caused by an Alternaria-type fungus,
but this has not been confirmed in Alabama. Ziram 76 DF has
been observed to suppress red spot in South Carolina. This trial
was conducted to determine if Ziram would reduce red spot se-
verity in Alabama. Results indicate that the 4- and 5-pound rates
of Ziram reduced red spot severity on peach fruit.
The experiment was conducted at the Chilton Research
and Extension Center in Clanton, Alabama, in 2002. The test con-
sisted of four treatments replicated four times in a randomized
complete block design. All treatments including the control re-
ceived two Bravo Weatherstik applications at petal fall and shuck
split and one preharvest application of Orbit at standard rates.
There were a total of 14 Ziram 76 DF applications applied weekly
starting on April 18 and ending on July 19. Twenty fruit were
collected from each replication at harvest and the number of red
spots per fruit was determined.
All Ziram 76 DF treatments performed better than the
unsprayed control in reducing severity of red spot on peach fruit
(see table). None of the treatments provided 100% control. There
were no significant difference between the 4- and 5-pound rates
of Ziram. The success of Ziram 76 DF in reducing red spot does
suggest that the disease is caused by a fungal pathogen.
The recommendation in South Carolina calls for three to
four applications of Ziram 76 DF at a rate of 4 pounds per acre
beginning seven to 10 days after shuck split and reapplication
every 14 days with a total of three to four applications, followed
by standard cover spray program. In this trial, Ziram was applied
weekly with a total of 14 applications, which may not be eco-
nomical. In 2003, the experiment will be repeated and the recom-
mendations suggested in South Carolina followed.
EFFECT OF ZIRAM 76 DF ON RED SPOT ON PEACHES, 2002
Treatment Percent of fruit with red spots (ranging from 0 to 15<)
rate/acre' 0 1-5 6-15 15<
Unsprayed control 46.2 16.2 12.5 25.0
Ziram 76 DF 3 lb 78.7 3.7 11.2 6.2
Ziram 76 DF 4 Ib 92.5 1.2 3.7 2.5
Ziram 76 DF 5 Ib 91.2 1.2 3.7 3.7
SEach treatment received 14 Ziram 76 DF applications.
SCREENING OF NEW INSECTICIDES FOR CONTROL
OF PLUM CURCULIO IN PEACHES
Wheeler Foshee, Robert Boozer, Dan Horton, and Johnny Staples
The plum curculio (Conotrachelus nenuphur) is the most
destructive pest of peaches grown in the Southeast. Control of
plum cucurlio in the past was very effective with organophos-
phates, particularly the use of encapsulated methyl parathion
until it was canceled by EPA in 1999. In 2001, use of azinphos-
methyl (Guthion), another organophosphate, was restricted in
the number of applications and this insecticide will be canceled
by the end of 2005.
The use of new chemistries as possible alternatives to or-
ganophosphates for plum cucurlio control needs evaluating. With
many new insecticides available, a faster screening method is
needed to select candidates for field testing. The objective of our
study was to develop a screening method and to test some newer
insecticides for the control of plum curculio in peaches.
During the spring of 2002, adult plum cucurlio were ob-
tained from traps within orchards in Chilton County, Alabama.
Insecticides evaluated (Table 1) were applied at an equivalent
rate of 50 gallons per acre using a Burkhard hand-applicator at a
rate of 0.5 FI to each plum cucurlio adult. All spray mixtures re-
ceived a 0.5 v/v addition of Destiny? surfactant, a modified seed-
oil. Mortality and insecticide intoxication data were taken at 24,
48, 72, and 96 hours postapplication.
Preliminary results indicate that the organophosphate
malathion and the pyrethroid bifenthrin (Capture) performed bet-
ter, in most cases, than all other treatments. At 24 hours
postapplication, the only 100% mortality/intoxicated state was
observed in bifenthrin (2x rate), malathion, and malathion (2x
rate) treatments. These were also the only treatments at the 48-
10
2001-2002 FRUIT AND 
VEGETABLE RESEARCH 
REPORT 
11
hour post-application point that reached 100% mortality/intoxi-
cation. Several other treatments did improve at the 48-hour post-
application evaluation (Table 2).
At 72 hours postapplication, bifenthrin (2x rate), malathion,
and malathion (2x rate) were still at 100% mortality/intoxication.
The treatments similar to these were fipronil, fipronil (2x rate),
bifenthrin, and thiamethoxam (2x rate) (Table 2).
The final assessment was at 96 hours and natural mortality
may have become a factor. The following treatments gave 100%
mortality/intoxication: bifenthrin (2x rate), malathion, malathion
(2x rate), and fipronil (2x rate). These had higher mortality/intoxi-
cation states than thiacloprid (2x rate) (33%) and the untreated 2x
check (17%) (Table 2).
The high level of plum curculio mortalityby malathion and
bifenthrin demonstrated that the older chemistries, at this point,
still have superior efficacy. It is worth noting that among other
materials tested, only fipronil at the 2x rate gave 100% mortality/
intoxication after 96 hours. Fipronil is known to be slow-acting,
so these results are noteworthy. At the 72-hour postapplication
point, the only new chemistries to give 83% control were the lx
and 2x rates offipronil. Thiamethoxam and thiacloprid failed, giv-
ing only 33% control.
Results are preliminary and further testing of these new
chemistries to validate the results is needed before field tested
can be suggested.
TABLE 1. INSECTICIDES EVALUATED, FORMULATION, RATES, AND AMOUNTS MIXED
FOR A 20ML MIX
Rate Amount of product
Treatment Formulation (ib ai/ac) per 20 ml mix 2x rates
Thiamethoxam(Actara?) 25wg 0.078 14.95 mg 29.9 mg
Thiacloprid (Calypso?) 4EC 0.2568 25.68 ml 51.3 ml
Fipronil (Termidor@) 0.8 SC 0.25 125 ml 250 ml
Bifenthrin (Capture@) 2EC 0.10 20 ml 40 ml
Malathion 50% EC 0.5 400 ml 800 ml
TABLE 2. RESULTS OF EFFICACY OF TESTED INSECTICIDES FOR CONTROL
OF PLUM CURCULIO
Percent intoxicated and mortality
Treatment 24 hours 48 hours 72 hours 96 hours
Thiamethoxam (Actara@) 33 cd 33 bc 33 bc 50 abc
Thiamethoxam - 2x (Actara@) 50 bc 50 abc 67 ab 67 abc
Bifenthrin (Capture@) 50 bc 67 ab 83 a 83 ab
Bifenthrin - 2x (Capture@) 100 a 100 a 100 a 100 a
Thiacloprid (Calypso?) 17 cd 33 bc 33 bc 50 abc
Thiacloprid - 2x (Calypso?) 33 cd 33 bc 33 bc 33 bc
Malathion 100 a 100 a 100 a 100 a
Malathion - 2x 100 a 100 a 100 a 100 a
Fipronil (Termidor?) 50 bc 67 ab 83 a 83 ab
Fipronil - 2x (Termidor?) 83 ab 83 ab 83 a 100 a
Untreated 50 bc 50 abc 17 c 50 abc
Untreated - 2x 0 d 0 c 0 c 17 c
Waller-Duncan K-ration T test. Means within columns followed by the same letter are not signifi-
cant, P<0.05.
2001-2002 FRUIT AND VEGETABLERESEARCHREPORT 11
12 
ALABAMA AGRICULTURAL 
EXPERIMENT STATION
FREQUNCY OF WARM WINTERS INC REASES NEED
FOR REST-BREAKING COMPOUNDS
Robert Boozer and Jim A. Pitts
One of the major concerns for peach producers in Central
Alabama is the occurrence of early spring freeze damage to
peaches. In addition, recent winter weather patterns have been
warmer than normal resulting in insufficient chill hours. Chilling
is necessary for normal rest breaking of fruit and leaf buds. One
chill hour is one hour at or below 45
0
F and total hours are re-
corded from October 1 through February 15. During five of the
past eight years, Central Alabama has not received sufficient
chill hours to completely satisfy the bud rest of 850 chill hour and
higher peach varieties. Some of these warmer winters have af-
fected leaf buds much more than fruit buds. Natural chilling is
more desirable, but rest- breaking chemicals could be beneficial
where chill hours might need to be supplemented.
Producers would like to be able to decide as late as pos-
sible before committing to applying rest-breaking chemicals. One
of the major reasons is the high cost of the only currently labeled
product, Dormex (hydrogen cyanamide). Other reasons are con-
cerns for breaking rest too early and trying to utilize as much
natural chilling as possible. Earlier work with Dormex indicated
that effective applications were made when 72% of natural chill-
ing for a variety had occurred. If chill hour accumulation picked
up during February, would waiting until late February or early
March before making an application work? This study was con-
ducted to evaluate early and late applications of rest-breaking
compounds.
Dormex and Dropp (thidiazuron) are two compounds that
have been reported and tested for the ability to stimulate buds
into their growth phase. The time of application and rates with
these compounds and the effect on fruit number, size, and shape
are important questions that are still being investigated. Of the
two compounds, only Dormex has a label at this time.
In 2002 a study was conducted at the Chilton Research
and Extension Center, Clanton, Alabama, in a block of'Cresthaven'
peaches, 950 chill hour variety. A total of six treatments at two
different application dates were evaluated on fruit bud develop-
ment, fruit size, shape, and total yield. Treatments consisted of
Dormex at 1.0%, 2.0%, and 4.0% plus nonionic surfactant at 0.25%
applied on January 28 and March 7 (early pink bud stage). Dropp
was applied at 200 parts per million and at 300 parts per million
plus 2% Dormant Oil on the same dates. As a standard, one
treatment consisted of an untreated control. Applications were
made with an air-blast sprayer using 130 gallons spray volume
per acre.
On January 28 the total number of chill hours occurring
since October 1,2001 was 706. Slightly over 74% of the chilling
requirement had been satisfied for 'Cresthaven' at the time of the
first application. Buds were in very early swell stage and con-
tained light green pollen grains as discerned at 10x magnification
when dissected. On March 7, when buds were at the early pink
stage, the second application of each treatment was made. Chill
hours totaled 923 by February 15 and 1129 by March 7, 2002.
Fruit bud losses within the 'Cresthaven' block appeared to
be related to weather as well as application ofDormex and Dropp.
The highest rate of Dormex thinned buds, but bud survival was
not statistically lower than the untreated control. Dropp seemed
to provide some level of freeze protection. Fruit bud develop-
ment was advanced by the use of Dormex at the first application
date, but not the later application. The amount of advancement
increased over time and was most significant at shuck-split. It
seems the use of Dormex reduces the number of heat units needed
to reach a certain fruit bud developmental stage (Figure 1). Dropp
did not significantly advance fruit buds on either application
date. Visible differences in leaf bud advancement were noted for
Dropp with even more leaf bud advancement noticed for Dormex,
after the first application.
Fruit were harvested four times from July 15 through July
26. Total number of fruit and size of fruit were not significantly
different among treatments. Adverse weather during the early
growth phase of fruit was thought to have contributed to poor
sizing. Size problems were also a problem in lower chill hour
peach varieties near this location.
Quality ratings on fruit shape were improved with Dormex
and Dropp (Figure 2). Individual ratings for appearance [round
(2), oval (4), tip (6), point (8), and suture (10)] were combined to
provide an overall rating. The higher the number the less desir-
able the characteristics. Fruit quality resulting from the first ap-
plication was improved by 2% and 4% Dormex, and 200 parts per
million Dropp over the untreated control. There were no statisti-
Figure 1. Fruit Bud Development as
Affected by Dormex and Dropp,
28 January Application
70- 11
M 1%Dr
mx
0 2%Drmx
I 4%Drmx
1I 200Dropp
DAT = days after treatment
ALABAMAAGRICULTURAL ExPERIMENT STATION12
2001-2002 FRUIT AND VEGETABLE RESEARCH REPORT
cal differences in fruit quality due to the second application treat-
ment.
Dormex exceeds Dropp as a compound for breaking rest in
fruit buds of peach. The only potential benefit from Dropp that
might justify further work would be the potential increase in fruit
bud hardiness during late winter and early spring freezes and
potential benefit to fruit shape. Time of application was shown to
be important for the use of Dormex. Applications made as late as
early pink are not effective in advancing fruit buds. Dormex seems
to do a good job in compensating chill hours and potentially
reducing heat unit requirements, but will not compensate for
poor growing conditions during early fruit development. Visible
impact on leaf growth was consistent with other studies using
Dormex. The physiological condition of the tree should be im-
proved by a more normal transition out of the rest stage into
growth stage and would likely benefit future productivity.
13
Figure 2. Fruit Quality Rating
28 January Application
18
S17.5
17-
16. 5-
S 16
a s
- 15-
14.5
ab
abc
bcd
d
Overall Fruit Shape
O UTC
E 1%Drmx
E 2%Drmx
O 4%Drmx
El 200Dropp
0 300Dropp
Higher value, more shape problems, max rating-22,
min rating=8, LSD P=0.05
EFFECTS OF THE RATE OF NITROGEN AND TIMES OF PRUNING
ON THREE VARIETIES OF PEACH IN CENTRAL ALABAMA, 2001
Bryan Wilkins, Robert Ebel, Robert Boozer, and Jim A. Pitts
This is a continuation of a study initiated in 2000 at the
Chilton Research and Extension Center in Clanton, Alabama. The
objective of the study was to determine an optimal nitrogen rate
and pruning regime for peach. The study is being conducted on
three varieties of peach with different ripening dates: 'Surecrop'
(early), 'Contender' (mid), and 'Encore' (late). During the grow-
ing season, trees were pruned once (winter), twice (winter and
shortly before harvest), or three times (right before hand thin-
ning, two to three weeks before harvest, and after harvest). Ni-
trogen was applied at 30, 60, and 90 pounds per acre per year. The
experiment was a blocked (five blocks), split-plot design with
nitrogen application as the main plot and pruning treatment as
the split plot. Data collected included weights of all prunings,
trunk cross sectional area, yield, fruit color, firmness, soluble
solids, and average fruit weight.
No fruit were produced in 2001. There were no significant
differences for 'Surecrop' (see table) in trunk cross sectional area
for the nitrogen treatment or pruning method. Pruning weights
by pruning method were different, with the trees that were pruned
twice having the least weight. Also photosynthesis and stomatal
conductance by method of pruning were different, with the trees
that were pruned three times a year having the highest rates.
There were no differences in trunk cross sectional area for
'Contender' with respect to amount of N applied and pruning
method. Pruning weights with respect to N rate and pruning
method were significantly different. Also photosynthesis and
stomatal conductance by method ofpruning were different, with
the trees that were pruned three times a year having the highest
rates.
There were no differences in trunk cross sectional area for
'Encore' with respect to N rate or pruning method. Pruning weights
by pruning method were different with the trees that were pruned
two times having the highest weights. Also photosynthesis and
stomatal conductance by method of pruning were significantly
different with the trees that were pruned three times a year hav-
ing the highest rates.
14 
ALABAMA AGRICULTURAL 
EXPERIMENT STATION
INFLUENCE OF NITROGEN RATE AND PRUNING METHOD ON PEACH
(PRUNUS PERSICA (L.) BATSCH) PERFORMANCE IN 2001
Trunk cross- Pruning Photo- Stomatal
sectional area weight synthesis conductance
(cm
2
/tree) (kg/tree) (Pmol C0
2
/
2
/s
1
) (mol H20 m-2S
)
'Surecrop'
Nitrogen rate (lbs/acre)
30 155 1 9.1 15.7 0.190
60 161 10.7 15.6 0.195
90 139 8.8 15.7 0.195
Pruning (no. times/year)
1 169 12.7 a 14.1 c 0.159 c
2 143 6.2 b 15.5 b 0.182 b
3 143 10.8 a 17.4 a 0.239 a
'Contender'
Nitrogen rate (Ibs/ac)
30 151 10.6 a 14.9 0.198
60 139 10.1 a 14.5 0.185
90 143 8.3 b 14.7 0.184
Pruning (no. times/year)
1 142 8.7 b 13.6 c 0.154 c
2 147 12.4 a 14.5 b 0.183 b
3 144 8.2 b 16.1 a 0.230 a
'Encore'
Nitrogen rate (lbs/ac)
30 150 14.8 11.3 0.149
60 154 15.5 11.6 0.154
90 141 14.4 11.1 0.145
Pruning (no. times/year)
1 148 9.2 b 10.7 b 0.128 c
2 154 21.9 a 11.0 b 0.150 b
3 143 12.1 b 12.2 a 0.170 a
Mean separation within columns by Duncan's Multiple Range Test p = 0.05, columns without
letters were not significantly different.
EFFECTS OF THE RATE OF NITROGEN AND TIMES OF PRUNING
ON TRME VARIETIES OF PEACH IN CENTRAL ALABAMA, 2002
Bryan Wilkins, Robert Ebel, Robert Boozer, and Jim A. Pitts
This is a continuation of a study initiated in 2000 at the
Chilton Research and Extension Center in Clanton, Alabama. The
objective of the study was to determine an optimal nitrogen rate
and pruning regime for peach. The study is being conducted on
three varieties of peach with different ripening dates: 'Surecrop'
(early), 'Contender' (mid), and 'Encore' (late). During the grow-
ing season,. trees were pruned once (winter), twice (winter and
shortly before harvest), or three times (right before hand thin-
ning, two to three weeks before harvest, and after harvest). Ni-
trogen was applied at 30, 60, and 90 pounds per acre per year. The
experiment was a blocked (five blocks), split-plot design with
nitrogen application as the main plot and pruning treatment as
the split plot. Data collected included weights of all prunings,
trunk cross sectional area, yield, fruit color, firmness, soluble
solids, and average fruit weight.
This report summarizes the results of the 2002 study. Prun-
ing weights for 'Surecrop' were significantly different with the
trees that were pruned three times per year having the smallest
14 ALABAMA AGRICULTURAL ExPERIMENT STATION
2001-2002 FRUIT AND VEGETABLE RESEARCH REPORT
weights (see table). There were significant differences in photo-
synthesis and stomatal conductance by pruning method with
the trees that were pruned one time having the lowest rates.
Method of pruning made a significant difference on the number
of fruit harvested and the total yield per tree. There were no
significant differences in fruit weight, red blush, or soluble sol-
ids. Trees that had the lowest N rate and were pruned three times
had firmer fruit.
For 'Contender', pruning weight by pruning method was
significantly different with trees being pruned one time having
the lowest weights. There were significant differences in photo-
synthesis and stomatal conductance by pruning method with
the trees that were pruned one time having the lowest rates. Total
number of fruit harvested, total yield, soluble solids, or red blush
were not affected by N or pruning treatments. There was a sig-
nificant difference in fruit weight and firmness by pruning method
with trees that were pruned one time having the lowest weights
and being the least firm.
Pruning weights for 'Encore' were significantly affected
by pruning method with trees that were pruned one time having
the highest weights. There were significant differences in photo-
synthesis and stomatal conductance by pruning method with
the trees that were pruned one time having the lowest rates.
There were significant differences in total number of fruit per tree
with trees being pruned one time having the most fruit. There
were no significant differences in total yield, fruit weight, soluble
solids, or red blush. Fruit firmness was affected by pruning with
fruit from trees that were pruned three times being the most firm.
At this time except for a few incidences, N rate has not had an
effect on any of the parameters for the three varieties in this
study.
INFLUENCE OF NITROGEN RATE AND PRUNING METHOD ON PEACH (PRUNUS PERSICA (.) BATSCH)
PERFORMANCE IN 2002
Pruning Photo- Stomatal Total Avg. fruit Fruit
weight synthesis conductance fruit/tree Yield weight firmness
(kg/tree) (gmol C0
2
/m
2
/s) (mol H
2
0 m-
2
s-1) (no) (kg/tree) (g/fruit) (Ibs)
'Surecrop'
Nitrogen rate (lbs/acre)
30 12.4 13.0 0.236 349 39.7 
164 7.7 a
60 14.2 13.4 0.242 380 42.0 
130 6.5 ab
90 11.2 13.2 0.237 404 42.7 113 5.7 b
Pruning (no. times/year)
1 18.3 a 12.1 b 0.202 b 396 a 44.6 a 121 6.7 ab
2 15.9 a 13.8 a 0.254 a 474 a 49.1 a 123 5.0 b
3 8.5 b 13.8 a 0.257 a 263 b 30.7 b 165 8.1 a
'Contender'
Nitrogen rate (lbs/acre)
30 14.4 12.1 0.260 369 53.8 155 
7.2
60 13.6 11.8 0.234 374 48.5 
147 7.3
90 14.0 11.6 0.228 401 49.5 145 7.3
Pruning (no. times/year)
1 22.4 a 10.8 b 0.187 b 427 50.9 139 b 11.9 b
2 15.8 b 12.1 a 0.267 a 367 53.4 153 ab 12.5 a
3 10.0 c 12.6 a 0.269 a 350 47.6 156 a 12.4 a
'Encore'
Nitrogen rate (Ibs/acre)
30 8.4 12.1 0.171 435 62.6 139 7.5
60 10.1 12.0 0.177 369 52.0 145 8.8
90 9.7 11.7 0.169 366 53.6 143 9.1
Pruning (no. times/year)
1 17.8 a 10.4 b 0.124 b 482 a 62.3 129 14.3 b
2 8.3 b 12.3 a 0.189 a 357 b 53.4 145 14.0 b
3 7.2 b 13.1 a 0.203 a 330 b 52.4 154 14.6 a
' Numbers within columns followed by the same letter are not significantly different (P=0.05, DMRT). Numbers in columns without
letters were not significantly different.
15
ALABAMA AGRICULTURAL EXPERIMENT STATION
EFFICACY OF THE SOIL FUMIGANTS TELONE C-35 AND TELONE II ON
GROWTH AND SURVIVAL OF PEACH TREES ON A REPLANT SITE
Bryan Wilkins, Robert Ebel, Jim A. Pitts, Robert Boozer, and Edward Sikora
Because of limited land availability, growers are often forced
to plant peach trees on land that had been planted in peach trees
for many years. Pathogens build up in soil planted in peach trees,
causing replanted trees to perform poorly. Preplant fumigants
have been developed to kill soil pathogens. The most popular
preplant soil fumigant is methyl bromide because of its high ef-
fectiveness; however, methyl bromide is scheduled to be re-
moved from the market in the next few years. Telone II
(dichloropropene) has been available for many years, but early
reports showed methyl bromide and chloroprycrin as being more
effective in promoting growth and survival of trees on replant
sites. Telone C-35 contains dichloropropene and chlorpycrin,
which should be more effective than Telone II in reducing soil
pathogens, and may be a suitable replacement for methyl bro-
mide. The objective of this
study was to compare growth,
survival, yield, and disease de-
velopment of peach trees
planted in soil treated with
Telone II and Telone C-35.
The experiment was con-
ducted on a site that had been
planted in peach trees since
1985. In the summer of 1999, the
trees were removed. Preplant
soil fumigation treatments in-
cluded Telone II, Telone'C-35,
and an untreated control that
was applied in an 8-foot band
or broadcasted across the en-
tire root zone. Telone II was
applied at a rate of 30 gallons
per acre and Telone C-35 at a
rate of 42 gallons per acre. The
experiment was set up as a ran-
domized complete block design
with five blocks containing
four adjacent trees with data
collected from the center two
trees. The trees in the block
were 'Sureprince' on Guardian
rootstock planted on a 12- by
20-foot spacing and trained to
a four-scaffold Y. The soil was sampled for ring nematode imme-
diately before fumigation and before planting.
There were no significant differences in the nematode popu-
lations throughout the block with the exceptions of spiral and
stubby root nematodes; however, there was no consistent trend
with respect to treatment (Table 1). Populations of all nematodes
were low throughout the experiment. There were no statistical
differences in truck cross sectional area or tree vigor for any of
the treatments in 2001 (Table 2). There was no statistical differ-
ences in number of fruit harvested, yield, and fruit quality. These
data demonstrate that these soil fumigants do not have a posi-
tive effect on growth and yield of peach when nematode popula-
tions are low.
TABLE 1. EFFECTS OF Two TELONE FORMULATIONS AT DIFFERENT APPLICATION
RATES AND METHODS ON THE POPULATION DENSITIES OF NEMATODES
IN 'SUREPRINCE' PEACH 1
Telone C35 Telone C35 Telone II Telone II
Nematode Control banded broadcast banded broadcast
(42 gal/ac) (42 gal/ac) (30 gal/ac) (30 gal/ac)
Spiral 2.4 ab 
2  
2.5 ab 0.9 b 3.8 a 1.1 b
Lesion 2.8 1.3 0.7 1.4 0.8
Ring 5.5 4.9 5.6 2.3 6.2
Stunt 3.1 0.4 2.2 0.4 2.2
Rootknot 0.9 1.8 1.1 1.0 2.2
Dagger 1.0 0.3 0.1 0.5 0.3
Tylenchus 5.8 5.2 2.2 1.9 5.0
Cyst 0 0.1 0 0 0
Reniform 0 0 1.0 1.0 0.1
Stubby Root 0 b 0 b 0 b 0 b 0.2 a
1 Means derived from data taken in 1999, 2000, 2001, and 2002.
2 Mean separation within columns by Duncan's Multiple Range Test p = 0.05, columns without
letters were not significantly different.
TABLE 2. EFFECTS OF TWO TELONE FORMULATIONS AT DIFFERENT APPLICATION
RATES AND METHODS ON THE GROWTH OF 'SUREPRINCE' PEACH
Trunk cross- Total fruit
Telone Rate Application sectional area harvested Yield
(gal/ac) (cm
2
/yr) (no) (lbs)
C35 42 Banded 18.12 174 38
C35 42 Broadcast 16.5 . 162 351
II 30 Banded 16.4 196 41
II 30 Broadcast 17.8 138 31
Control 14.1 144 33
Means derived from data taken in 2000, 2001, and 2002.
2Mean separation within columns by Duncan's Multiple 
Range Test p = 0.05, columns without
letters were not significantly different.
16
2001ALUATION OF FNGICIDE SPRAYS FOR PECAN SCAB CONTROL
Edward J. Sikora and Jason Burkett
Pecan scab, a fungal disease of pecan, is the most limiting
disease to pecan production in the Southeast. To control scab,
growers must maintain a calendar-based spray program from bud-
break through mid August. In 2001, several new fungicides
(Stratego) and some experimental compounds (Folicur and Emi-
nent) were evaluated for scab control. Results showed that all
the fungicide treatments were significantly better than the
unsprayed control in controlling leaf and nut scab.
The experiment was conducted on a block of 'Desirable'
pecan trees at the E. V. Smith Research Center in Shorter, Ala-
bama. All of the fungicide treatments (spray programs) were ini-
tiated within 10 days after bud-break and followed a 14-day sched-
ule throughout the season. Leaf scab was assessed on June 3
and nut scab was rated on September 10.
The weather conditions were favorable for leaf scab devel-
opment. All the fungicide programs were significantly better than
EVALUATION OF FUNGICIDE SPRAY PROGRAMS FOR PECAN SCAB CONTROL, 2001
Application Leaf scab Nut scab
Treatment Rate/acre timing I 
(%) (%)
Unsprayed control - - 10.8 a 2 87.5 a
Super Tin 80 WP 7.5 oz Sprays 1-8 7.1 b 43.0 bcd
Folicur 3.6 F + 6 oz Sprays 1-3
Induce 0.06%
then
Super Tin 80 WP 7.5 oz Sprays 4-8 6.6 b 49.1 bc
Stratego 2 EC 8 oz Sprays 1-3
then
SuperTin 80 WP 7.5 oz Sprays 4-8 2.1 c 37.2 de
Dodine 65 WP 32 oz Sprays 1-3
then
Stratego 2 EC 8 oz Sprays 4-7
then
SuperTin 80 WP 7.5 oz Spray 8 3.3 c 42.2 cd
Dodine 65 WP 32 oz Sprays 1-3
then
Stratego 2 EC 10 oz Sprays 4-7
then
SuperTin 80 WP 7.5 oz Spray 8 3.3 c 38.1 de
Eminent 125 SL 8 oz
+
Dodine 65 WP 16 oz Sprays 1-8 3.5 c 50.3 b
Eminent 125 SL 1 pint Sprays 1-3
then
Agri Tin 80 WP 7.5 oz Sprays 4-8 2.8 c 49.8 bc
Super Tin 80WP 3.75 oz
+
Dodine 65 WP 16 oz Sprays 1-8 7.2 b 33.1 e
Enable 75 W 2 oz
+
Dodine 65 WP 16 oz Sprays 1-8 1.5 c 50.0 b
Orbit 4 oz
+
Dodine 65 WP 16 oz Sprays 1-8 2.3 c 30.6 e
LSD (P=0.05) 2.9 7.8
Total of eight sprays.
2 Numbers followed by the same letter are not significantly 
different.
the unsprayed control in con-
trolling leaf scab (see table).
The Super Tin full-season
program, the Folicur/Super
Tin block-program and the
Super Tin plus Dodine tank-
mix program had significantly
higher levels of leaf scab than
the other seven fungicide
programs.
All the fungicide pro-
grams controlled nut scab
significantly better than the
unsprayed control. The Su-
per Tin plus Dodine tank mix
and Orbit plus Dodone tank-
mix programs were signifi-
cantly better than the other
treatments with the exception
of the Stratego/Super Tin
block program and the
Dodine/Stratego (10 ounce)/
Super Tin program.
2001-2002 FRUIT AND VEGETABLERESEARCHREPORT 17
y v i w
18 
ALABAMA AGRICULTURAL 
EXPERIMENT STATION
ALTERNATE BEARING IN SATSUMAS
Monte Nesbitt, Robert Ebel, William Dozier, Ron McDaniel. and Malcomb Pegues
Satsuma mandarin trees are commonly known to experi-
ence alternate bearing. Alternating years of heavy and light pro-
duction is a serious obstacle to developing a thriving satsuma
industry in Alabama because marketing problems arise when the
crop fluctuates from year to year. In the 2000 crop season, 11-
year-old 'Owari' trees at the Gulf Coast Research and Extension
Center (GCREC) in Fairhope, Alabama, averaged 473 pounds of
fruit, with some individual trees yielding as much as 792 pounds.
In the following year, average tree yield in the same grove was
only 157 pounds per tree.
Harvest date is a factor that can contribute to alternate
bearing in some crops. A satsuma tree with 792 pounds of fruit
may actually have some 3,900 individual fruit on it (five fruit per
pound average), which can take a great deal of time to hand
harvest, especially in a commercial planting with 100 or more
trees per acre. Ifremoval of the fruit is extended over a 30- to 60-
day period, the fruit that remain on the tree continue to act as
sinks for carbohydrates, depressing the trees' ability to build up
carbohydrates essential to produce a normal crop the following
year.
In 1999 and 2000, a study was conducted at the GCREC to
determine the effects of late fruit harvest on alternate bearing. Six
trees were completely harvested on each of three dates: Novem-
ber 1, December 1, or January 1, and yield was measured the
following season. Yield was significantly reduced in 2000 only
when harvest was delayed until January 1. The lower yield for
EFFECT OF ARVESTDATE ON YIELD OF SATSUMA,
2000 AND 2001
Harvest date Pounds/tree 2000 Pounds/tree 2001
November 1 576 271
December 1 559 122
January 1 419 232
January-harvested trees, although significant, is not dramatic,
and most growers harvest most of their fruit before January 1.
Thus normal harvesting, which usually begins in early Novem-
ber and extends into mid-December, may not be a major contrib-
uting factor to alternate bearing, at least on a moderately large
crop. The average yield of trees in this study in 1999 was 372
pounds, which may not have been enough to cause severe alter-
nate bearing.
The 2000 crop was larger and alternate bearing did occur in
2001 (see table). Although it appeared that yields in 2001 were
reduced by the December harvest date, the differences were not
statistically significant, due to a high degree of variation in yield
in the test trees. The variation was caused by freeze damage to
the foliage in the winter of 2000-01. Trees in the study that lost
less than 40% of their foliage produced 300 pounds per tree in
2001, and those that lost more produced only 100 pounds per
tree. Winter injury to foliage combined with heavy production
and delayed harvest are major causes for alternate bearing in
satsumas.
SATSUMA DISEASE SuiRVEY OF ALABAMA
Kathy McLean, Edward Sikora, Robert Ebel, S. L. Burchett, and Monte Nesbitt
Satsuma mandarins are a type of citrus that are character-
istically loose-skinned, brightly colored, and have a very flavor-
ful taste. Citrus trees were introduced into Florida by Spanish
explorers in 1565. Small satsuma orchards developed along the
Gulf of Mexico by the late 1800s. However, severe winters late in
the century severely diminished the numbers of trees surviving.
Satsuma acreage did increase again with milder weather and by
the early 1920s, approximately 18,000 acres of satsumas were
growing in the coastal regions of Alabama, Florida, and Louisi-
ana. In Alabama, satsumas were considered to produce more
consistent crops, ripen within the growing season, and require
less cold protection than other citrus. However, satsuma trees
are not tolerant to extended freezing temperatures and multiple
severe winters in the 1930s and 1940s depreciated the satsuma
acreage.
Alabama currently has a new and emerging commercial
satsuma industry in the Mobile Bay area. But the type.and extent
of disease incidence in the growing region is currently not well
characterized. A survey was conducted in November of 2000 and
2001 to determine the disease incidence and pathogens present
in the satsuma acreage in Alabama.
Seven orchards representing the majority of the commer-
cial acreage were surveyed for symptomatic fruit and foliage in
2000 and 2001. Samples of fruit and foliage withdisease symp-
toms were collected from each orchard, labeled, and immediately
placed in plastic bags in a cooler of ice. Samples were trans-
ported back to the laboratoryand placed in a cold room at 40C.
Within 24 hours samples were photographed and disease symp-
toms described. Tissue sections were excised from the leaves
and fruits of each diseased sample collected. Tissue sections
were surface-sterilized and aseptically plated on acidified potato
dextrose agar. Plates were incubated at 24
0
C for 10 days, during
and after which colonies of fungi growing from the tissue were
identified, or subcultures were prepared for later identification.
ALABAMAAGRICULTURAL ExPERIMENT STATION18
2001-2002 FRUIT AND 
VEGETABLE RESEARCH 
REPORT 
19
Seven diseases were identified. Alternaria leaf spot and
brown spot of satsuma caused by Alternaria alternata Fr.
(Kiessler) pv. citri was found in 85 and 75% of the orchards
surveyed in 2000 and 2001, respectively (see table). Mycelia ofA.
alternata pv. citri is dark olive in color and grows rapidly at
240C. Conidia are dark, obclavate to elliptical with both cross and
longitudinal septa borne in apical chains. On leaves the lesions
appeared as circular or irregular blighted areas that were often
surrounded by a yellow halo. On the mature fruit the symptoms
varied from small dark specks to large black lesions sometimes
surrounded by a yellow halo. Fruit blemishes will significantly
reduce the market price and can be an economical factor in pro-
duction.
Anthracnose, caused by Colletotrichum gloeosporiodes
(Penz.) Penz. & Sacc., was found in 85 and 50% of the orchards
surveyed in 2000 and 2001, respectively. Mycelia of C.
gloeosporiodes is gray to brown in color with spore masses that
appear salmon in color. Acervuli are produced which are disk-
shaped with dark setae among the conidiophores. Conidia are
abundant, hyaline, one-celled, oblong to fusiform. Symptoms on
leaves include necrotic areas which may coalesce. Anthracnose
on mature fruit are usually considered secondary but appear as
brown to black spots or tear-stain blemishes.
Blue and green molds of fruit caused by Penicillium spp.
were found in 71 and 87% of the orchards in 2000 and 
2001,
respectively. Mycelia of Penicillium spp. appeared blue to blue
gray or olive green in the center surrounded by white to light-
colored areas. Conidia are one-celled, globose in shape and borne
on phialids in dry basipetal chains. Symptoms on mature fruit
include soft discolored areas 5 to 10 centimeters in diameter, to
the entire fruit surface being encompassed by mycelium and
spores.
PERCENT OF SATSUMA ORCHARDS AND SAMPLES
INFESTED IN THE LABAMA SURVEY, 2000 AND 2001
Disease Orchards infested Samples infested
2000 2001 2001
Alternaria leaf spot 85 75 43
Anthracnose 85 50 22
Penicillium fruit rot 71 87 27
Melanose 85 25 8
Twig die back 71 37 4
Distorted fruit 29 75 15
Mean 73 58 20
Melanose of mature fruits, caused by Phomopsis citri H.
Fawc. (Sacc.) Traverso & Spessa., was found in 85 and 25% of
the orchards in 2000 and 2001, respectively. Phomopsis citri pro-
duces white to cream, ropy mycelia with dark pycnidia in scat-
tered stroma. Conidia are ovoid to fusoid (alpha) or filiform and
curved (beta). Symptoms on mature fruit appear as small, brown
discrete specks or streaks of tear stains across the fruit surface.
Twig tip dieback and distorted fruit were observed in 71
and 37% and 29 and 75% of the orchards in 2000 and 2001, re-
spectively; however, no causal agent for these disorders was
determined.
Overall, 73 and 58% of the orchards were infested with at
least one fungal pathogen in 2000 and 2001, respectively. How-
ever, the incidence and severity of fruit and foliar diseases of
satsuma in each orchard were relatively light. The 2000 and 2001
seasons were considered dry years for Alabama, which may have
resulted in low disease pressure.
EVALUATION OF FUNGICIDES FOR BOTRYTIS GRAY MOLD CONTROL
ON STRAWBERRIES, 2002
Edward Sikora and Jim A. Pitts
Botrytis gray mold is a fungal disease that causes a fruit
rot of strawberries in Alabama. The loss of the fungicides Benlate
and Ronilan in recent years has reduedu the number of fungi-
cides available to growers to combat this disease. In 2001-2002, a
number of fungicides in various spray programs were evaluated
to determine their efficacy against this disease. Results indicate
that all the fungicide programs evaluated controlled gray mold
equally well. There also was no apparent difference among the
fungicides in controlling anthracnose, a fungal disease that was
a common problem in strawberry production fields in 2002.
The test was conducted at the Chilton Research and Ex-
tension Center in Clanton, Alabama. The strawberry variety 'Chan-
dler' was transplanted to the field in October of2001. Plants were
grown on raised beds with black plastic mulch and drip irrigation.
Treatments were initiated in the spring of 2002 at 10% bloom.
There were a total of eight fungicide applications made on the
following days: March 20, March 28, April 3, April 10, April 17,
April 26, May 1, and May 8. Total marketable fruit weight and
percent fruit with symptoms of Botrytis gray mold and/or anthra-
cnose were determined.
All the fungicide programs had higher marketable fruit
weights than the unsprayed control (see table). The program
that alternated Rovral with Topsin M plus Captan produced ap-
proximately 8% less marketable fruit than the Topsin M plus
Captan full season program. There were no apparent differences
among the fungicide programs in their ability to control Botrytis
gray mold or anthracnose.
2001-2002 FRUIT AND VEGETABLERESEARCHREPORT 19
20 
ALABAMA AGRICULTURAL 
EXPERIMENT STATION
EVALUATION OF FUNGICIDES FOR CONTROL OF BOTRYTIS GRAY MOLD
AND ANTHRACNOSE OF STRAWBERRIE, 2002
Fungicide treatment/ Marketable Botrytis gray Fruit
Rate/acre fruit (g) mold (%) anthracnose (%)
Unsprayed control 4317 11.0 2.3
Topsin M 1 Ib
+
Captan 50WP 4 Ib 6360 > 1.0 5.4
Topsin M 1 Ib
+
Captan 50WP 4 lb
ALTERNATED WITH
Elevate 50WG 1.5 Ib
+Captan 50WP 4 Ib 6164 >1.0 5.5
Topsin M 1 lb
+
Captan 50WP 4 Ib
ALTERNATED WITH
Switch 62.5 WG 14 oz 6336 >1.0 4.1
Topsin M 1 lb
+
Captan 50WP 4 Ib
ALTERNATED WITH
Rovral 50WP 2 lb 5325 2.9 4.1
Topsin M 1 lb
+
Captan 50WP 4 Ib
ALTERNATED WITH
Cabrio EG 14 oz 5854 >1.0 5.5
ALABAMA AGRICULTURAL ExPERIMENT STATION20
2001-2002 FRUIT AND VEGETABLE RESEARCH REPORT
VE GE TABLE PAP"IERS
EVALUATION OF FUNGICDES FOR CONTROL OF ALERNARIA LEAF SPOT
OF CABBAGE
Edward Sikora and Arnold Caylor
More than 800 acres of cabbage are planted annually in
Alabama with an estimated value of $2.5 million. The main dis-
ease problem of cabbage is Alternaria leaf spot. Production of
marketable cabbage can be severely affected if this disease goes
uncontrolled. Alternaria causes a leaf spot that can result in sig-
nificant defoliation in the field. In storage, the disease can pre-
dispose infected cabbage heads to soft rot bacteria.
Fungicides with the active ingredient chlorothalonil or
maneb are labeled for control ofAlternaria leaf spot on cabbage
but are only moderately effective against the disease. For this
reason, alternative products were evaluated in this study through
the IR-4 program.
The trial was conducted in 2001 at the North Alabama Hor-
ticulture Research Center in Cullman, Alabama. Cabbage was
transplanted in mid September. Each treatment consisted of a
one-row plot 15 feet long. The experiment consisted of four treat-
ments, replicated five times, in a randomized complete block de-
sign. Disease ratings were taken in late November and early De-
cember. Cabbage was harvested and total number of marketable
heads, total marketable weight, and average marketable head
weight were determined.
Alternaria leaf spot was observed in trace amounts on one
replication of the untreated control. There were no significant
EVALUATION OF UNGICIDES FOR CONTROL
OF FOLIAR DISEASE OF CABBAGE, 2001
Treatments Marketable Marketable Average
rate/acre 1 heads weight head weight
(no/plot) (Ib/plot) (Ib)
Untreated 9.75 a 2 63.57 a 6.55 a
Bravo Weather Stik 10.50 a 67.15 a 6.40 a
1.50 pt
BAS 500 9.75 a 59.92 a 6.15 a
0.75 lb
BAS 500 10.50 a 67.02 a 6.35 a
1.00 lb
1 Bravo Weather Stik and the BAS 500 treatments were applied
three times at seven-day intervals beginning when Alternaria leaf
spot first appeared in late November.
2 Means with the same letter are 
not significantly different.
differences among the treatments in terms of total number of
marketable heads produced, total marketable head weight, or av-
erage marketable head weight (see table). No symptoms of phy-
totoxicity among the fungicide treatments were observed.
E FFECT OF NITROGEN SOURCE ON QUALITY AND YIELD
OF 'LAROUGE' IRISH POTATO
Joseph Kemble, Edgar Vinson, and Tony Dawkins
Growers have often asked the question "How does nitro-
gen source affect various vegetable crops?" In the case of toma-
toes, research has shown that tomatoes perform better (improved
quality and fewer fruit defects) when they are fertilized solely
with nitrate-nitrogen (potassium nitrate, calcium nitrate) as op-
posed to ammonium-nitrogen (ammonium nitrate). This experi-
ment was initiated to determine if nitrogen source would affect
the quality and yield of Irish potato. After one season, no differ-
ences were found among the treatments; however, this experi-
ment will be repeated.
An experiment was initiated at the Sand Mountain Research
and Extension Center in Crossville, Alabama, to determine the
effect of various percentages of preplant and sidedress applica-
tions of ammonium nitrate and/or calcium nitrate on Irish potato.
There werewere four treatments: (1) 100% calcium nitrate (preplant)/
100% calcium nitrate (sidedress); (2) 100% calcium nitrate (pre-
plant)/100% ammonium nitrate (sidedress); (3) 100% ammonium
nitrate (preplant)/100% ammonium nitrate (sidedress); and (4)
100% ammonium nitrate (preplant)/100% calcium nitrate
(sidedress).
Soil pH and fertility (except for nitrogen) were adjusted
based on soil test results from the AU Soil Testing Lab. Preplant
nitrogen treatments were applied to meet 50% of the crop's nitro-
gen need. Seed pieces of 'LaRouge' were cut, treated with fungi-
cide, and set on March 15, 2002. The remaining nitrogen was
applied in two sidedress treatments, the first sidedress one month
21
after planting, and the second about one month after the first able yield, tuber sizes, or culls among the four treatments 
(see
sidedress. table). In fact, no differences were found among the treatments
Vines were rolled prior to applying Diquat. Tubers were for skin set or skin color (data not shown). Some lack of differ-
dug on July 3, 2002 and then graded and weighed. Tubers were ence could be do to the extended hot, dry weather during most of
separated based on size as size A potatoes (diameter greater than the late spring through midsummer before the tubers were har-
or equal to 1 7/8 inches), size B potatoes (diameter 1 1/2 to 1 1/7 vested. This experiment will be repeated next season.
inches), or culls (diameter of
less than 1 1/7 inches). Total _
marketable yield equaled the EFFECT 
OF NITROGEN SOURCE ON QUALITY AND 
YIELD OF 'LAROUGE IRISH
sum of the size A and B pota- 
POTATO AT SAND MOUNTAIN 
RESEARCH AND EXTENSION 
CENTER,
toes for a particular 
treatment. 
CROSSVILLE, AL, 
2002
In addition to grading and
weighing, skin set and skin Total
color were evaluated, marketable
No differences were Treatment 
yield Size A 
1 Size B 
Cull
3
found in terms of total market- 
(lb/ac) (lb/ac) (lb/ac) 
(lb/ac)
(3) Am nit/Am nit 17,739 a 4 15,397 a 2,341 a 478 a
(4) Am nit/Ca nit 17,249 a 14,944 a 2,305 a 472 a
(1) Ca nit/Ca nit 17,067 a 15,046 a 2,021 a 823 a
(2) Ca nit/Am nit 15,936 a 13,818 a 2,118 a 424 a
Size A potatoes have a >1 7/8 inch diameter.
2 Size B potatoes have a 1 1/2 - 1 1/7 inch diameter.
SCull potatoes are those with a diameter of less than a 1 1/7 inch.
4 Values followed by the same letter are not 
significantly different according to
Range Test (p<0.05).
Duncan's Multiple
EFFECT OF SPLIT APPLICATION OF DESICCANT AND VINE ROLLING
ON QUALITY AND YIELD OF 'LAROUGE' IRISH POTATO
Joseph Kemble, Edgar Vinson, and Tony Dawkins
Growers in Alabama commonly use a vine desiccant, such
as Diquat, on Irish potatoes in order to kill the actively growing
vines to facilitate harvesting. These desiccants also aid in pro-
moting skin set - a toughening of the potato skin, which helps
extend the post-harvest life of the tuber. In other potato-produc-
ing regions of the United States, growers often use split applica-
tions of desiccants (with reduced rates) and have found favor-
able results and fewer problems with stem-end browning of tu-
bers. In addition, vine rolling, in combination with split applica-
tions of desiccant, has also been found to aid in skin set. This
research was initiated to determine if these procedures could aid
Irish potato growers inAlabama. In 2002, research indicated that
marketable yields of potatoes sprayed with spit applications of
desiccant were greater, although not statistically, than those
treated with a single higher rate of desiccant. This work will be
continued in 2003.
This experiment was initiated at the Sand Mountain Re-
search and Extension Center in Crossville, Alabama, to deter-
mine the effect of split applications of the desiccant Diquat and
vine rolling on the quality and yield of'La Rouge' Irish potatoes.
There were four treatments: (1) single application of Diquat (1
quart per acre); (2) split application of Diquat (1 pint per acre,
then a second application four days after the first); (3) single
application of Diquat (1 quart per acre), vine rolling; and (4) split
application of Diquat (1 pint per acre, then a second application
four days after the first), vine rolling.
Soil pH and fertility (except for nitrogen) were adjusted
based on soil test results from the AU Soil Testing Lab. Preplant
nitrogen treatments were applied to meet 50% of the crop's nitro-
gen needl. Seed pieces of'LaRouge' were cut, treated with fungi-
cide, and set on March 15, 2002. The remaining nitrogen was
applied in two sidedress treatments, the first sidedress one month
after planting, and the second about one month after the first
sidedress.
Vines in treatments 3 and 4 were rolled on June21. Diquat
was applied on June 25 on all treatments at either 1 quart per acre
or 1 pint per acre. A second application of Diquat was made on
June 29 to treatments 2 and 4 (the 1-pint-per-acre 
treatments).
Tubers were dug on July 3 and then graded and weighed. Tu-
bers were separated based on size as size A potatoes (diam-
22 ALABAMA AGRICULTURAL ExPERIMENT STATION
eter greater than or equal to 1 7/8 inches), size B potatoes compared to treatments 1 and 3 (single application of Diquat)
(diameter of 1 1/2 to 1 1/7 inches), or culls (diameter of less (see table). Treatments 1 and 3 (single application of Diquat)
than 1 1/7 inches). Total marketable yield equaled the sum of produced the lowest marketable yield, although it was not statis-
the size A and B potatoes for a particular treatment. tically lower (see table). Based on these results, this experiment
Treatments 2 and 4 (spilt applications of Diquat) showed a will be repeated in 2003.
slight, although not significant, increase in total marketable yields
EFFECT OF SPLIT APPLICATION OF DESICCANT AND VINE ROLLING ON QUALITY AND
YIELD OF 'LAROUGE' IRISH POTATO AT SAND OUNTAIN
RESEARCH AND EXTENSION CENTER, CROSSVILLE, AL, 2002
Total
marketable
Treatment yield Size A' Size B
2  
Cull
3
(lb/ac) (lb/ac) (Ib/ac) (Ib/ac)
Treatment 2 19,306 a
4  
16,964 a 2,341 ab 581 a
Treatment 4 19,027 a 16,256 a 2,771 a 532 a
Treatment 3 18,894 a 16,571 a 2,323 ab 696 a
Treatment 1 16,202 a 14,617 a 1,585 b 484 a
1 Size A potatoes have a >1 7/8 inch diameter.
2 Size B potatoes have a 1 1/2 
- 1 1/7 inch diameter.
3 Cull potatoes are those with a diameter 
of less than a 1 1/7 inch.
4 Values followed by the same letter are not significantly 
different according to Duncan's Multiple
Range Test (p<0.05).
EVALUATION OF SYNTHETIC AND BIOLOGICAL FUNGICIDES
FOR CONTROL OF POWDERY MILDEW ON PUMPKIN
Edward Sikora and Tony Dawkins
Powdery mildew is a common fungal disease ofpumpkin in
Alabama. Powdery mildew reduces yield by decreasing the size
and number of fruit or the length of time the crop has to mature.
In 2002, both commercially available synthetic fungicides
(Quadris, Bravo, Ridomil, and Microthiol Disperss) as well as
two experimental biological fimungicides (QRD 283 and 286) were
evaluated. Results showed that Microthiol Disperss (a sulfur-
based product) controlled powdery mildew better than the other
products evaluated.
This trial was conducted at the Sand Mountain Research
Station in Crossville, Alabama. The variety 'Appalachian' was di-
rect seeded into the field in late June. The experiment consisted of
six treatments, replicated four times, in a randomized complete block
design. Each treatment/replication consisted of a one-row plot, 20
to 25 feet long. The fungicide programs were started when the
vines began to run. Fungicides were applied every seven days
(some treatments alternated between two products). Disease rat-
ings were taken approximately 10 days before harvest. Yield data
were yet not available for inclusion in this publication.
Powdery mildew was 
the dominant disease 
observed in
the trial (low levels of downy mildew were also noted). The
EVALUATION OF FUNGICIDES FOR CONTROL OF POWDERY
MILDEW, SAND MOUNTAIN, ALABAMA, 2002
Treatments/rate' % Powdery mildew
Unsprayed control
Quadris (11 oz/acre)
ALTERNATED WEEKLY WITH
Bravo Ultrex (2.7 lb./acre)
Microthiol Disperss 80 DF (8 lb./acre)
QRD 286 AS (1% by volume)
QRD 283 WP (4 Ib./acre)
QRD 283 WP (4 lb./acre)
ALTERNATED WEEKLY WITH
Ridomil Gold Bravo WP (3 Ib./acre)
75.5
24.7
17.2
49.2
32.2
27.0
'Spray programs were initiated at vine run and sprayed every 7
days.
Microthiol Disperss treatment had the lowest incidence of pow-
dery mildew among the treatments (see table). Microthiol Disperss
is a sulfur-based product, and sulfur fungicides have proven to
be very effective in controlling powdery mildew in previous trials
2001-2002 FRUIT AND VEGETABLERESEARCHREPORT 23
24 
ALABAMA AGRICULTURAL 
EXPERIMENT STATION
in Alabama. The Quadris/Bravo treatment and both QRD 283
treatments also performed well in this trial.
Microthiol Disperss and other sulfur products do a good
job in controlling powdery mildew on pumpkins. Growers should
be aware, however, that sulfur is only effective against powdery
mildew, not downy mildew. Growers need to scout pumpkin fields
weekly to determine if wet weather diseases such as downy mil-
dew are developing. If diseases other than powdery mildew ap-
pear, the grower must begin spraying broad-spectrum materials
such as Bravo and Quadris to reduce damage from these other
diseases.
EVALUATION OF IPM SPRAY PROGRAMS FOR CONTROL
OF FOLIAR DISEASES OF PUMPKIN, 2001
Edward Sikora, Josepb Kemble, and Tony Dawkins
Downy mildew and powdery mildew are two common fun-
gal diseases of pumpkin in Alabama. Powdery mildew is most
common in dry years while downy mildew is considered a wet-
weather disease. Both diseases reduce yield by decreasing the
size and number of fruit or the length of time the crop has to
mature. In 2001, a powdery-mildew-tolerant pumpkin variety was
evaluated with two Integrated Pest Management (IPM) strate-
gies. The two-IPM strategies were as follows. First, the fungicide
spray program was initiated if and when disease was first ob-
served in the field by way of a twice-a-week-scouting program;
and second, the period between fungicide applications was ex-
tended from seven days to 10 to 12 days.
Results were greatly affected by the appearance of a new
disease to Alabama. The fungal disease Plectosporium blight
developed early in our trials and was confused with spray burnm
by the researchers. This was the first report of Plectosporium
blight in Alabama. This resulted in greater defoliation and lower
yields in the two scouting treatments than in the standard seven-
day fungicide program.
This trial was conducted at the Sand Mountain Research
and Extension Center in Crossville, Alabama. The variety 'Mer-
lin' was direct seeded into the field on June 20. The experiment
consisted of five treatments, replicated five times in a random-
ized complete block design. Each treatment/replication consisted
of a one-row plot, 30 feet long. The experiment compared four
fungicide programs and an unsprayed control. The four fungi-
cide programs consisted of Quadris alternated with Bravo Ultrex
on a seven-day or a 10- to 12-day schedule with programs initi-
ated at vine run or when disease was first observed in the field.
Disease ratings were taken on September 12.
EFFECTIVENESS OF IPM PROGRAMS ON DISEASE
DEVELOPMENT ON A POWDERY-MILDEW TOLERANT
PUMPKIN VARIETY, SAND MOUNTAIN, 2001
Fungicide timing/ Downy Plectosporium
When initiated ' mildew blight
Unsprayed control 48.0 43.0
7 days/vine run 12.0 2.0
10-12 days/vine run 29.0 9.0
7 days/scouting 28.0 37.0
10-12 days/ scouting 32.0 34.0
1 Treatments were sprayed on a seven-day or 10-12 day inter-
val. Treatments were initiated at vine run or at first appearance
of disease when following a biweekly scouting program. The
fungicide program for all treatments, with the exception of the
unsprayed control, was Quadris alternated with Bravo Ultrex.
Results showed that 'Merlin' grown following the seven-
day fungicide schedule initiated at vine-run had the lowest lev-
els of downy mildew and Plectosporium blight (see table) and the
highest marketable yields (data not shown). No differences in
yield were observed among the other three fungicide spray pro-
grams. Three to four fewer fungicide applications were required
when following the scouting program resulting in lower input
costs except for the scouting, possibly offsetting loss in market-
able yields. This trial demonstrates that growers/field scouts must
be aware of all potential plant diseases and pests that may dam-
age a crop.
ALABAMAAGRICULTURAL ExPERIMENT STATION24
2OMPARISON OF TERRARY G EPANDTERRAPY TO METHYL BROMIDE
As GROWTH PROMOTERS FOR 
TOMATO, 2001
Edward Sikora and Arnold Caylor
TerraPy B and TerraPy G are organic products that have
been shown to reduce plant stress and plant disease activity by
stimulating soil microbiological activity and promoting nutrient
uptake of various horticultural and agronomic crops in Europe
and Asia. The objective of this study was to determine if the
products would promote growth and boost yields of tomato in
Alabama. Results show that four weeks after application, plants
treated with TerraPy G had a higher health rating than those
treated with TerraPy B. Unfortunately, no significant differences
were observed in terms of total marketable fruit weights or in fruit
size among the treatments.
This experiment was conducted at the North Alabama Hor-
ticultural Research Center in Cullman, Alabama. Tomato trans-
plants were set in the field on June 6. Plants were grown on raised
beds covered with white plastic mulch and drip irrigated. The
experiment consisted of four treatments replicated six times in a
randomized complete block design. Each treatment replication
consisted of a one-row plot, 20 feet long. The methyl bromide
treatment was applied at the standard commercial rate approxi-
mately one month before transplanting. TerraPy B (20 grams per
square meter) and TerraPy G (20 grams per square meter) were
applied as a soil drench at transplanting. Plots were sprayed
weekly with a tank mix of mancozeb plus copper for foliar disease
control. Plots were evaluated for plant health (height, color, and
vigor) four and eight weeks after transplanting. Tomatoes were
PLANT HEALTH RATINGS AND TOTAL MARKETABLE
EIGHT OF TOMATOES, 2001
Treatment Plant health Total marketable
ratings weight
4 weeks (Ib)
TerraPy G (20 g/m
2
) 3.4 a 1 108.3 a
TerraPy B (20 g/m
2
) 2.6 b 90.5 a
Methyl bromide 3.2 ab 122.3 a
Control (water only) 3.0 ab 101.1 a
SNumbers followed by the same letter are not significantly dif-
ferent.
harvested weekly at the breaker stage and graded for size then
weighed by size (extra large, large, medium, and small) and total
marketable weights were determined.
TerraPy G had the highest plant health rating among the
treatments (see table), significantly higher than the TerraPy B 20
treatment four weeks after transplanting. There were no differ-
ences among treatments eight weeks after transplanting. There
were few significant differences in yield among treatments (data
not shown). The methyl bromide treatment produced a signifi-
cantly higher medium fruit weight than TerraPy B. There were no
significant differences in total marketable yield among treatments.
2001-2002 FRUIT AND VEGETABLERESEARCHREPORT 25
ALABAMA AGRICULTURAL EXPERIMENT STATION
EVALUATION OF TERRA Y G AT MULTIPLE RATES
AS A GROWTH PROMOTER FOR TOMATO, NORTH ALABAMA, 2001
Edward J. Sikora and Arnold Caylor
TerraPy G is an organic product that has been shown to
reduce plant stress and plant disease activity by stimulating soil
microbiological activity and promoting nutrient uptake of vari-
ous horticultural and agronomic crops in Europe and Asia. The
objective of this study was to determine the optimum rate of
TerraPy G as a growth promoter on tomato. Results indicate that
TerraPy G at the high rate (20 grams per square meter) may be
phytotoxic to tomato, based on growth ratings at four and eight
weeks after application. The low (2 grams per square meter) and
high (20 grams per square meter) rates of TerraPy G produced
significantly lower marketable fruit weights than the control and
the 5 and 10 grams per square meter TerraPy G treatments.
This experiment was conducted at the North Alabama Hor-
ticultural Research Center in Cullman, Alabama. Tomato trans-
plants were set in the field on May 25. Plants were grown on
raised beds covered with white plastic mulch and drip irrigated.
The experiment consisted of five treatments replicated five times
in a randomized complete block design. Each treatment replica-
tion consisted of a one-row plot, 20 feet long. The TerraPy G
treatments were applied as a soil drench at transplanting.
Plots were sprayed weekly with a tank mix of mancozeb
plus copper for foliar disease control. Plots were evaluated for
plant health (height, color, and vigor) four and eight weeks after
transplanting. Tomatoes were harvested weekly at the breaker
PLANT HEALTH RTINGS AND TOTAL MARKETABLE
WEIGHT OF TOMATOES, CULLMAN 2001
Treatment Plant health Total marketable
-ratings- weight
4 weeks 8 weeks (Ib)
TerraPy G (2 g/m
2
) 3.2 a 1 3.0 a 139.6 b
TerraPy G (5 g/m
2
) 3.2 a 3.0 a 159.9 ab
TerraPy G (10 g/m
2
) 3.2 a 2.8 a 164.9 ab
TerraPy G (20 g/m
2
) 2.0 b 2.2 b 137.0 b
Control (water only) 3.6 a 3.0 a 178.9 a
' Numbers followed by the same letter are not significantly dif-
ferent.
stage and graded for size then weighed by size (extra large, large,
medium, and small) and total marketable weights were determined.
TerraPy G (20 grams per square meter) had the lowest plant
health rating at both four and eight weeks after transplanting
(see table). The low (2 grams per square meter) and high (20
grams per square meter) rates of TerraPy G produced signifi-
cantly lower total marketable fruit weights than the control and
the 5 and 10 grams per square meter TerraPy G treatments. Based
on the results of this trial and an identical trial at the Sand Moun-
tain Research and Extension Center, TerraPy G at any tested rate
did not appear to promote plant health or improve yield produc-
tion of tomatoes in Alabama.
26
2001-2002 FRUIT AND VEGETABLE RESEARCH REPORT
EVALUATION OF TERRAPY G AT MULTIPLE ]RATES
AS A GROWTH PROMOTER FOR TOM AT, SAND MOUNTAIN, 
2001
Edward J. Sikora and Tony Dawkins
TerraPy G is an organic product that has been shown to
reduce plant stress and plant disease activity by stimulating soil
microbiological activity and promoting nutrient uptake of vari-
ous horticultural and agronomic crops in Europe and Asia. The
objective of this study was to determine the optimum rate of
TerraPy G as a growth promoter on tomato. Results indicate that
TerraPy G at any of the tested rates had little effect on growth
and yield of tomato.
This experiment was conducted at the Sand Mountain Re-
search and Extension Center in Crossville, Alabama. Tomato trans-
plants were set in the field on May 24. Plants were grown on
raised beds covered with white plastic mulch and drip irrigated.
The experiment consisted of five treatments replicated five times
in a randomized complete block design. Each treatment replica-
tion consisted of a one-row plot, 20 feet long. The TerraPy G
treatments were applied as a soil drench at transplanting.
Plots were sprayed weekly with a tank mix of mancozeb
plus copper for foliar disease control. Plots were evaluated for
plant health (height, color, and vigor) five weeks after transplant-
ing. Tomatoes were harvested weekly at the breaker stage and
graded then weighed by size (extra large, large, medium, and
small) and total marketable weights were determined.
PLANT HEALTH RATINGS AND TOTAL MARKETABLE
EIGHT OF TOMATOES, SAND MOUNTAIN 2001
Treatment Plant health Total marketable
ratings weight
5 weeks (Ib)
TerraPy G (2 g/m
2
) 3.2 a 1 167.2 a
TerraPy G (5 g/m
2
) 3.2 a 147.2 a
TerraPy G (10 g/m
2
) 2.8 a 165.8 a
TerraPy G (20 g/m
2
) 2.6 ab 160.2 a
Control (water only) 2.0 b 165.7 a
SNumbers followed by the same letter are not significantly dif-
ferent
The control treatment had the lowest plant health rating
five weeks after transplanting; however, the ratings were not
significantly different from the TerraPy G treatments at 10 and 20
grams per square meter (see table). There were no significant
differences among treatments in total marketable fruit weight.
Based on the results of this trial and an identical trial at the North
Alabama Horticultural Research Center in Cullman, TerraPy G at
any tested rate did not appear to promote plant health or improve
yield production of tomatoes in Alabama.
GREENHOUSE TOMATO TRIAL REVEALS FEW DIFFERENCES
Joseph Kemble, Edgar Vinson, Floyd M. Woods, and Raymond Thomas
Production of greenhouse tomatoes is becoming a popular
business among vegetable growers and nursery owners. The
quality of greenhouse tomatoes and their off season availability
help insure a steady market.
Greenhouse or hydroponic tomato production is labor in-
tensive and requires steadfast, daily oversight and care. Many
variables must be monitored and choices made to insure a pro-
ductive crop. One such choice is that of variety selection. For
greenhouse production, tomatoes specifically bred for that pur-
pose, not for field production, should be used.
A greenhouse tomato variety trial was conducted at Miss
Emily's Hydroponic Tomatoes in Coker, Alabama, in the spring of
2002. Six-week-old tomato seedlings were planted on February
18, 2002. Tomato seedlings were planted into 2-cubic-foot poly-
ethylene bags filled with coconut coir. Three bags containing
two plants represented each variety. Tomato varieties were repli-
cated four times and were arranged in a randomized complete
block.
Tomatoes were harvested once weekly fromApril 4 through
May 3 for a total of six harvests. Tomatoes were weighed and
graded. Grades and corresponding fruit diameters (D) of fresh
market tomatoes were adapted from the Tomato Grader's Guide
(Circular ANR 643 from the Alabama Cooperative Extension Sys-
tem) and graded as extra-large (D greater than 2.9 inches), large
(D greater than 2.5 inches), medium (D greater than 2.3 inches),
and small (D less than 23 inches). Marketable yield was calcu-
lated by combining the extra-large, large, medium, and small grades
(Table 1). Culled tomatoes were separated based on physiologi-
cal disorders such as concentric cracking, radial cracking, cat-
facing, blossom end rot, and russeting.
In marketable yield, marketable number, and size distribu-
tion categories, there were no significant differences among va-
rieties (Table 1). Total cull weights were significantly different
among varieties (Table 2). 'Style' had significantly higher total
cull weights than '73-36RZ' and 'Blitz' but was similar in cull
weight to all other varieties. 'Grace' and 'Blitz' also differed in
27
28 
ALABAMA AGRICULTURAL 
EXPERIMENT STATION
total cull weight with 'Grace' having a higher total cull weight
than 'Blitz'. Blossom end rot was highest with 'Style' when com-
pared to 'Blitz' but when compared to other varieties there were
no differences. 'Mariachi' had a higher incidence of radial crack-
ing than 'Blitz,' while the remaining varieties were similar to 'Blitz'
in terms of cracking.
There were few differences among varieties in
physiochemical attributes such as pH and soluble solids (obrix).
'Style' was similar to 'Grace', 'Trust', and 'Blitz' but had a signifi-
cantly lower pH than 'Mariachi' and '73-36RZ'. 'Mariachi' and
'73-36RZ' were similarto 'Grace', 'Trust', and 'Blitz'. Soluble sol-
ids content of '7336RZ' were higher than 'Blitz' but similar to all
other varieties.
When compared to standard varieties 'Blitz', 'Grace', and
'Trust', the other varieties differed little. Of the three standards,
'Blitz' appeared to be the better performer overall when compari-
sons were made with newer Varieties. Though few differences
existed among varieties in terms of quality (cull fruit and
physiochemical attributes), there were no real differences in mar-
ketable yield.
TABLE 1. MARKETABLE YIELD OF TOMATO FRUIT FROM A GREENHOUSE TOMATO VARIETY TRIAL,
COKER, ALABAMA 20021
Variety Marketable Marketable Extra large Large Medium Small Average
yield yield yield yield yield yield weight/fruit
(Ib/plot) (no/plot) (lb/plot) (lb/plot) (Ib/plot) (lb/plot) (oz)
Blitz 33 a 
2  
68 a 21 a 7.88 a 3.18 a 0.84 a 7.98 a
Mariachi 33 a 64 a 20 a 8.87 a 3.67 a 0.82 a 8.35 a
Trust 31 a 51 a 20 a 5.81 a 4.35 a 1.00 a 9.53 a
73-36RZ 28 a 58 a 18 a 7.47 a 2.84 a 0.63 a 7.89 a
Grace 25 a 54 a 14 a 7.12 a 3.10 a 0.82 a 7.56 a
Style 22 a 57 a 11 a 7.49 a 3.02 a 0.71 a 6.41 a
Significance 3 ns ns ns ns ns ns ns
1Trial was conducted at Miss Emily's Hydroponic Tomatoes. Yields are based on six-plant plots.
2 Numbers followed by different letters 
are significantly different based on 
Duncan's Multiple Range Test.
3 ns indicates not significant at p=0.05.
TABLE 2. CULL DISTRIBUTION AND PHYSIOCHEMICAL ATTRIBUTES OF TOMATO FRUIT
FROM A GREENHOUSE TOMATO VARIETY TRIAL, COKER, ALABAMA 20021
Variety Catfacing Concentric Blossom Radial pH Soluble
Total cull cracking end rot cracking Russeting solids
(Ib/plot) (Ib/plot) (lb/plot) (Ib/plot) (Ib/plot) (Ib/plot) (?brix)
Style 11.4 a 2 - 0.5 1.0 a 4.4 ab 5.0 4.72 a 3.10 b
Grace 9.2 ab - 0.5 0.2 ab 3.1 ab 4.5 4.75 ab 3.35 ab
Mariachi 8.4 abc - - 0.1 ab 4.5 a 2.6 4.75 ab 3.30 ab
Trust 8.2 abc 0.2 0.2 0.1 ab 4.2 ab 2.8 4.77 ab 3.20 b
73-36RZ 6.4 bc 0.1 1.4 - 2.7 ab 1.5 4.80 b 3.35 ab
Blitz 5.0 c 0.3 0.1 0.5 ab 1.2 b 2.3 4.82 b 3.70 a
Significance3 * ns ns ** ** ns ** ns
Trial was conducted at Miss Emily's Hydroponic Tomatoes. Yields are based on six-plant plots.
2 Numbers followed by different letters are significantly different 
based on Duncan's Multiple Range Test.
3 ** indicates significance at p=0.05 ns indicates 
not significant at p=0.05.
ALABAMAAGRICULTURAL ExPERIMENT STATION28
EFFECTS OF POULTRY LITTER ON THE YIELD AND QUALITY
F STAKED T A VEGETES
Edgar Vinson, Joseph Kemble, and Jeff Sibley
Vast accumulations of poultry litter have prompted the
search for beneficial and environmentally sound incorporation
of this by-product into the fertility programs of vegetable grow-
ers. To determine the effects of poultry litter on specific veg-
etable crops, more research must be done.
As a contribution to this multifaceted endeavor, a study
was conducted at the E.V. Smith Research Center in Shorter, Ala-
bama, in the spring of 1999 and 2000 to determine the effects of
poultry litter on yield and quality of staked tomatoes. Quality
attributes measured were citric acid content, soluble solids, total
acidity, and the types of culls produced such as radial cracking,
blossom end rot, and catfacing.
Composted poultry litter was applied at rates of 30, 60, 120,
240, and 480 pounds of nitrogen per acre and incorporated into
the soil with a roto-tiller prior to mulch bed formation. No methyl
bromide was applied. 'Mt. Spring' tomato transplants were planted
on these poultry-litter-amended beds. Yields of tomatoes grown
in poultry litter were compared to the control treatment, which
received 120 pounds of nitrogen per acre from a mixture of cal-
cium nitrate and potassium nitrate (7-0-7) and was fumigated
with 67% methyl bromide and 33% chloropicrin (see figure).
In 1999, tomato fruit yields decreased with increasing
amounts of poultry litter. Poultry litter applied at rates of 30 and
60 pounds per acre were sufficient for tomato production. In 2000
tomato yields were significantly higher in the 480 pounds-per-
acre rate than in all other treatments. In this case, test plots were
overcome by nutsedge so tomatoes grown in the heavily amended
soils fared better because of a more abundant supply of nutri-
ents for which to compete. The production of cull fruit such as
blossom end rot, cracking, and cat-facing was similar in all treat-
ments (see table). Total fruit acidity was significantly lower in the
480 pounds-per-acre treatment when compared to the control
(see table). Total acidity,
soluble solids, and citric acid
1
Marketable yield data for 1999 and 2000 were analyzed separately because of treatment
and year interactions.
2
Columns headed by different letters represent 
means that are significantly different.
3
"Com-" =non-methyl bromide treated control 
and "com+" = methyl bromide treated control.
content play a role in tomato
flavor. Increased total acid
content has been known to
reduce flavor scores in taste
tests.
According to the 1999
experiment, poultry litter ap-
plied at a rate of 30 pounds of
nitrogen per acre is enough
to produce yields above that
of inorganic fertilizer without
increasing the occurrence of
culled fruit. A similar conclu-
sion was reached in the 2000
study where tomatoes grown
in poultry litter treatments pro-
duced similar yields as toma-
toes grown in with inorganic
fertilizer. Physiochemical at-
tributes of tomatoes grown in
soils amended with poultry lit-
ter at this rate are comparable
to those grown using inor-
ganic fertilizers.
bt.p p p p
2001-2002 FRUIT AND VEGETABLE -RESEARCHREPORT 29
30 ALABAMA AGRICULTURAL EXPERIMENT STATION
EFFECT OF VARYING AMOUNTS OF POULTRY LITTER ON CULLS
OF 'MT. SPRING' TOMATOES, 20001
Poultry litter Blossom Cat- Citric Soluble
treatment Crack end rot facing acid solids pH
(lb/ac) (Ib/ac) (lb/ac) 
(%) (%)
30 Ibs N acre-' 362.0 a 4 144 a 2,957 a 0.37 bcd 4.5 a 4.1 a
60 Ibs N acre-' 784.0 a 673 a 4,526 a 0.34 cd 4.1 ab 4.1 a
120 Ibs N acre-' 663.0 a 1,251 a 3,259 a 0.40 b 3.9 b 4.1 a
240 Ibs N acre-' 1,026.0 a 1,251 a 6,457 a 0.40 b 4.1 ab 4.0 a
480 Ibs N acre-' 2,294.0 a 673 a 3,439 a 0.48 a 3.9 b 4.1 a
Control-
2  
302.0 a 144 a 3,379 a 0.39 cd 4.2 ab 4.2 a
Control+
3  
1,328.0 a 385 a 4,523 a 0.33 d 4.4 a 4.2 a
1 Study was conducted at E.V. Smith Research Center in Shorter, Alabama. Results are in pounds
per acre-'.
2 Non methyl bromide 
treated control.
3 Methyl bromide treated 
control.
4 Within columns, means followed by different 
letters are significantly different.
-HIZOBACrERIAL-MEDIATED MATURE PLANT RESISTANCE
IN TOMATO TO CUCUMBER MOSAIC VIRUS
John F. Murphy, M.S. Reddy, and Joseph W. Kloepper
The use of plant growth-promoting rhizobacteria (PGPR)
to induce resistance to infection by Cucumber mosaic virus
(CMV) in tomato has been investigated. Previous studies have
showed that selected PGPR strains induced protection against
CMV in tomato plants under greenhouse and field conditions
and that PGPR treatments protected tomato plants from the white-
fly-transmitted Tomato mottle virus (ToMoV) under field condi-
tions consisting of heavy whitefly/ToMoV pressure.
Mature plant resistance is an established but poorly un-
derstood phenomenon whereby plants vary in their susceptibil-
ity to infection by certain pathogens due to their age or stage of
development. For example, in bell pepper plants the mechanism
of mature plant resistance to CMV involves interference in pro-
cesses that allow the virus to move throughout the plant. While
previous studies focused on the use of PGPR to induce resis-
tance against viruses, recent efforts have shifted to evaluate the
enhanced plant growth effects that result from treatments con-
sisting of combinations of PGPR formulated in chitosan. The
purpose of this study was to determine whether enhanced plant
growth may serve to shorten the window of time leading to ex-
pression of mature plant resistance.
Tomato 'Solar Set' seed was sown in Speedling trays un-
der greenhouse conditions. Five PGPR preparations (termed LS
series) were used in each experiment. Each LS preparation con-
tained industrially formulated endospores of two Bacillus strains
and the formulation carrier chitosan. Tomato seeds were sown
directly into the LS/soilless growth medium mixture. Treatments
consisted of five LS preparations and two non-bacterized con-
trol treatments. One control treatment was the same age as plants
in the LS treatments, while the second was 10 days older. Plants
in the older control treatment were the same size as those in the
LS treatments. Plants were mechanically inoculated with CMV
when the same age control treatment plants were at the early 5 to
6 leaf stage.
Three growth parameters were evaluated at the end of the
experiment [30 days postinoculation (dpi)]: plant height (a mea-
sure of stem growth from one day prior to CMV inoculation to 30
dpi), plant fresh weight of above ground tissues, and the number
of flowers and fruit. The mean plant height was significantly
greater for all LS treatments and the older control compared with
the control treatment (Table 1). No differences were observed for
TABLE 1. RESPONSE OF LS- AND MOCK-TREATED
TOMATO PLANTS TO INOCULATION WITH CMV
1
Treatment Height Weight Flower/fruit
(cm) (g) (no)
LS254 26.4 b 123.5 cd 10.6 b
LS255 26.5 b 130.0 d 13.6 cd
LS256 26.5 b 119.5 cd 13.4 cd
LS257 24.3 b 117.7 cd 13.7 cd
LS213 26.9 b 114.5 cd 12.4 bc
Control (old) 25.5 b 99.7 b 10.3 b
Control 19.6 a 30.7 a 1.8 a
'Tomato plant response to Cucumber mosaic virus was mea-
sured at 30 days post inoculation.
2001-2002 FRUIT AND VEGETABLE RESEARCH REPORT
plant height among LS treatments and the older control treat-
ment. The mean plant fresh weight was significantly greater for
all LS treatments and the older control treatment compared with
the control treatment. In addition, plant fresh weight for all LS
treatments was significantly greater than for the older control
treatment. The mean number of flowers and fruits was signifi-
cantly greater for all LS treatments and the older control than for
the control treatment. LS treatments 255,256, and 257 had signifi-
cantly more flowers and fruit than plants in the LS254 and older
control treatments.
Initial signs of vein clearing and mosaic first occurred in
control treatment plants by seven dpi, whereas plants in the
other treatments were symptomless at that time. When plants
were rated for symptom severity, the control treatment had a
significantly higher average disease rating than for each of the
other treatments at 14 and 28 dpi, whereas the LS and older con-
trol treatments did not differ from one another. More than half of
the plants in the LS254, LS255, LS213 and older control treat-
ments and half of the plants in LS256 remained symptomless at
28 dpi.
CMV accumulation in young, uninoculated leaves was
measured at 14 and 28 dpi by ELISA. At 14 dpi, the mean ELISA
value for samples collected from each LS and the older control
31
treatment was significantly lower than for the control treatment
(Table 2). CMV accumulation in plants treated with LS213 was
significantly lower than in plants treated with LS257 but neither
treatment differed from the other PGPR treatments or the older
control. When plants were tested at 28 dpi, mean ELISA values
for treatments LS254, LS255, LS256, LS213, and the older control
were significantly lower than for LS257 and the control treat-
ment.
ELISA data, used to determine percent infection within
each treatment, revealed that significantly fewer plants were in-
fected with CMV in the PGPR treatments LS255, LS213, and the
older control than in the control treatment at 14 dpi (Table 2). At
28 dpi, treatments LS254, LS255, LS213, and the older control had
significantly fewer infected plants than in the control treatment.
In addition, the percentage of infected plants was significantly
lower for treatments LS254, LS213, and the older control than for
LS257.
Since mature plant resistance has been used as a manage-
ment tool to reduce virus infection and associated yield losses
under field conditions, the LS-based treatments reported here
may offer a form of PGPR-mediated induced mature plant resis-
tance that would integrate well with other pest management
schemes.
TABLE 2. DETECTION OF CMV IN LEAF TISSUES OF PGPR-TREATED
AND NON-TREATED TOMATO PLANTS'
Treatment ELISA- 
-Percent infection
3-
14 dpi 28 dpi 14 dpi 28 dpi
LS254 0.496 bc 0.328 b 40 abc 30 c
LS255 0.362 bc 0.455 b 35 c 55 bc
LS256 0.633 bc 0.409 b 60 abc 60 abc
LS257 0.697 b 0.715 a 65 abc 85 ab
LS213 0.318 cd 0.336 b 25 c 30 c
Control (old) 0.423 bc 0.332 b 35 c 35 c
Control 1.228 a 0.774 a 90 ab 90 a
'Cucumber mosaic virus was detected by enzyme-linked immunosorbent assay (ELISA) at 14 and
28 days postinoculation.
2 Mean ELISA values for CMV-inoculated 
tomato plants subjected to the stated treatments.
The numbers represent the mean ELISA value for all (20) plants per treatment. Different
letters represent a significant difference of the means at P-0.05.
3 Percent infection is based on the number 
of samples shown to be infected with CMV
based on ELISA per 20 samples for each treatment. Different letters represent a significant
difference of the means at P-0.05.
ALABAMA AGRICULTURAL EXPERIMENT STATION
EVALUATION OF CUPROFI MZ DISPERSS FOR THE CONTROL
OF CERCOSPORA LEAF SPOT ON TOIMATO, 2002
Edward Sikora and Arnold Caylor
Cuprofix MZ Disperss is a new product from Cerexagri. It 
is
a fungicide/bactericide that combines the active ingredients cop-
per and mancozeb. Mancozeb is effective in controlling fungal
diseases such as early blight, whereas copper acts as both a fungi-
cide and a bactericide and is effective against bacterial leaf spot.
This trial was conducted to determine the efficacy of Cuprofix
MZ Disperss against Cercospora leaf spot on tomato. Cercospora
leaf spot is often a problem on fall-grown tomatoes in Alabama.
Results indicate that the 4- and 6-pound-per-acre rates of Cuprofix
MZ Disperss applied weekly were effective in controlling the
disease.
This trial was conducted at the North Alabama Horticul-
tural Research Center in Cullman, Alabama. Tomatoes were trans-
planted in July of 2002. Plants were grown on bare ground and
drip irrigated. The experiment consisted of five treatments, repli-
cated five times, in a randomized complete block design. Each
treatment/replication consisted of a one row plot bordered on
each side by an unsprayed guard row. Rows were 25 feet long
with an in-row spacing of 18 inches. Treatments were applied
weekly. Assessment of disease was conducted on October 12
and October 23. Yield data were not available at the time of pub-
lication.
EFFECTIVENESS OF TREATMENTS ON
CERCOSPORA LEAF SPOT ON TOMATO
Treatments Percent Cercospora leaf spot
rate/acre October 12 October 23
Untreated control 14.0 69.2
Cuprofix MZ Disperss 4.0 Ib 2.6 12.3
Cuprofix MZ Disperss 6.0 lb 2.0 8.6
Cuprofix MZ Disperss 4.0 lb 10.4 22.2
ALTERNATED weekly with
Actigard 1/3 - 3/4 oz +
Cuprofix MZ Disperss 2.0 Ib
ManKocide 5.0 Ib 16.0 60.6
The 4- and 6-pound rates ofCuprofix MZ Disperss had the
lowest Cercospora leaf spot ratings on both rating dates (see
table). It appears the 2-pound rate of Cuprofix MZ Disperss in
the alternating treatment was too low to control Cercospora leaf
spot. ManKocide performed poorly with disease ratings in the
same range as the untreated control.
IR-4 FOOD-USE RESEARCH ON TURNIP -GREENS
Edward Sikora and Arnold Caylor
Alabama is the second leading producer of turnip greens
in the United States with more than 2,000 acres planted annually
with an average yield estimated at 11,000 pounds per acre. The
crop is valued at more than $5 million in Alabama. Production of
turnip greens can be affected by a variety of plant diseases.
Damage can range from minor spotting to complete loss of a crop
depending on the pathogen involved. Because leaves are typi-
cally the marketable products in green production in Alabama, a
minor leaf spot problem can cause a significant loss in yield.
Only a few fungicides are labeled for use on turnip 
greens
inAlabama. For this reason, funding from the IR-4 program was
used to evaluate non-labeled and new chemistry fungicides for
control of foliar diseases of turnip. Results indicated that two
rates of Quadris F and BAS 500 (an experimental product from
BASF) reduced damage from Alternaria leaf spot compared to an
unsprayed control on the variety 'Purple Top'.
These experiments were conducted at the North Alabama
Horticultural Research Center in Cullman in 2001. The turnip
varieties 'Purple Top' and 'Shogun' were transplanted in Sep-
EVALUATION OF FUNGICIDES FOR CONTROL
OF ALTERNARIA LEAF SPOT ON TURNIP GREENS, 2001
Treatments/ -Percent Alternaria leaf spot-
rate/acre Shogun Purple Top
Untreated 4.2 a 1 14.2 a
BAS 500 (1 Ib/acre) 4.7 a 7.0 b
BAS 516 (0.66 Ib/acre) 4.5 a 10.0 a
Quadris F (142 mI/acre) 3.7 a 7.2 b
Quadris F (237 ml/acre) 3.5 a 6.2 
b
SNumbers followed by the same letter are significantly differ-
ent.
tember into separate trials. Each experiment consisted of five
treatments replicated four times in a randomized complete block
design. Plants were grown in one-row plots that were 15 feet
long. Treatments included (1) an unsprayed control, (2) BAS 500
(1 pound per acre), (3) BAS 516 (0.66 pound per acre), (4) Quadris
F (142 milliliters per acre), and (5) Quadris F (237 milliliters per
32
2001-2002 FRUIT AND VEGETABLE RESEARCH REPORT
acre). Fungicide applications were initiated at the first sign of
disease and a total of three applications were made at 14-day
intervals. Disease ratings were taken in late November and mar-
ketable top and root weights were determined at harvest.
Alternaria leaf spot, a common fungal disease of turnips,
was the most common disease detected in these trials (see table).
Disease pressure was relatively low in the 'Shogun' trial appar-
ently due to the variety's higher level of resistance to the dis-
ease. There were no significant differences in disease ratings
among the fungicides and the unsprayed control in the 'Shogun'
trial. Damage from Alternaria leaf spot was significantly higher
on the unsprayed control and in the BAS 516 treatment com-
pared to the other three fungicide treatments in the 'Purple Top'
trial. There were no significant differences in yield (top or root
weights) among the treatments in either trial (data not shown).
33


Alabama's
Agricultural
Experiment
Station
Auburn University
Research Unit identification
) Main Agricultural Experiment Station, Auburn.
'k Alabama A&M University
r E. V. Smith Research Center, Shorter.
1. Tennessee Valley Research and Extension
Center, Belle Mina.
2. Sand Mountain Research and Extension Center,
Crossville.
3. North Alabama Horticulture Research Station,
Cullman.
4. Upper Coastal Plain Agricultural Research
Station, Winfield.
5. Chilton Research and Extension Center,
Clanton.
6. Piedmont Substation, Camp Hill.
7. Prattville Agricultural Research Unit, 
Prattville.
8. Black Belt Research and Extension Center,
Marion Junction.
9. Lower Coastal Plain Substation, Camden.
10. Monroeville Agricultural Research Unit,
Monroeville.
11. Wiregrass Research and Extension Center,
Headland.
12. Brewton Agricultural Research Unit, Brewton.
13. Ornamental Horticulture Research Center,
Spring Hill.
14. Gulf Coast Research and Extension 
Center,
Fairhope.