Upland Variety Testing Evaluation in Southeastern Arizona
E.R. Norton, L.J. Clark, and H. Borrego
Abstract
Two separate variety evaluations were conducted in southeastern Arizona during the
2004 cotton growing season. The two locations were on grower-cooperator fields in the
Upper Gila River Valley located in Thatcher, AZ (Graham County) and in the Sulfur
Springs Valley in Kansas Settlement, AZ (Cochise County). Twelve varieties were
selected for the Graham County evaluation and fifteen in the Cochise County evaluation.
These varieties included several transgenic varieties and ranged in maturity from early to
full-season varieties. Several Acala varieties were also evaluated in both the Graham
and Cochise County tests. Both evaluations were conducted using a randomized
complete block design with each variety replicated four times. Plant measurements were
collected in season on several dates from the Graham County evaluation. End of season
plant measurements were collected from the Cochise County evaluation. Lint yield was
estimated at each location by harvesting the entire plot and weighing the harvested seed
cotton with a weigh wagon equipped with load cells. Sub samples were collected from
each plot for fiber quality and percent lint determinations. Total crop value for each
variety was calculated by using the fiber quality premium/discount and using a $0.52 per
pound price. The total price is then multiplied by total lint yield to obtain the total value
for that particular variety. Results observed in the Graham County evaluation were
similar to those in 2003. Lint yield ranged from 1200 to over 1600 lbs. lint/acre. The
FiberMax variety FM991BR produced the highest lint yield and also the highest total
crop value at over $950/acre. Results from the Cochise County evaluation demonstrated
the potential that high fiber quality can have on total crop value. Lint yields ranged from
600 to over 1200 lbs. lint/acre. The highest yielding variety (ST5242BR) did not produce
the highest crop value. Because of the higher fiber quality of the Acala varieties, they
produced the highest value at approximately $630/acre.
Introduction
One of the most important decisions that a cotton producer makes ever year, that has a tremendous effect
on the rest of the season, is variety selection. Selection of a properly adapted variety and appropriately
timed planting is critical to achieving optimum returns in a cotton production system. The rising cost of
seed and technology fees that accompany many of the commonly planted varieties places an ever
increasing level of importance on making the right decision for a particular farm. There are many choices
available to a grower today which make the task of variety selection that much more difficult.
Several sources may provide information on variety evaluations but it is critical to have regionally based
information and, whenever possible, to base a decision on multiple years of evaluation for a particular
variety. That is not always possible but should be done to the extent possible. The University of Arizona
conducts a thorough evaluation of commercially available cotton varieties in several regions around the
state. One of those regions is southeastern Arizona which includes Graham and Cochise counties. The
tests provide an unbiased evaluation of available varieties. These tests are almost exclusively conducted in
grower-cooperator fields which provide for an added dimension of applicability to the local producers.
Materials and Methods
Two separate studies were conducted in the southeastern region of the state. One was conducted in
Thatcher , AZ with Layton Farms and Ranches as the cooperator while the second evaluation took place in
Kansas Settlement, AZ with Milton Schmitt as the cooperator.
Arizona Cotton Report (P-142) May 2005
115
Thatcher Location
The evaluation conducted at the Thatcher location included 12 varieties with a variety of transgenic traits.
Table 1 lists the varieties along with their associated maturity ratings and transgenic traits. These varieties
were planted in four, 38” row plots that extended the full length of the irrigation run of approximately
1,260 feet. Each variety was replicated four times in a randomized complete block design. Plant
measurements were collected over the course of the growing season to evaluate crop growth and
development. These measurements included; plant height, number of mainstem nodes, position of the first
fruiting branch, number of retained fruiting structures on the first two positions of each fruiting branch, and
number of nodes above the top, first position, fresh bloom.
Kansas Settlement Location
A total of fourteen varieties were included in the Cochise County evaluation (Table 2). Varieties were
planted in two, 36” row plots that extended half way around the center pivot irrigation system. Each plot
length was different and was accounted for when final lint yield calculations were made. Plots were
arranged in a randomized complete block design with four replications. Due to lack of labor and distance,
plant measurements were only collected at harvest and included plant height, number of mainstem nodes,
and position of first fruiting branch.
At both evaluation locations yield estimates were made by harvesting each entire experimental plot and
weighing the resultant seedcotton with a cotton weigh wagon equipped with load cells. Sub samples were
collected from each experimental unit that was subsequently cleaned and ginned at the University of
Arizona Maricopa Agricultural Center ginning facility. Lint samples were then submitted to the USDA
Phoenix Classing Office for HVI analysis to obtain fiber quality estimates. All yield and fiber quality data
from both locations were analyzed according to procedures outlined by the SAS Institute (2002) including
analysis of variance and means separation using a Fisher’s least significant difference test.
The value for each of the varieties was calculated at each location by determining a premium or discount
using the USDA CCC loan schedule. This premium/discount is based upon fiber quality characteristics and
is added to the base USDA loan rate of $0.52 per pound. This price is multiplied by the lint yield to
calculate a total value for that variety.
Results
Thatcher
The 2004 spring season brought several difficulties in stand establishment. Several of the varieties in this
test had to be replanted in certain areas of the field. These varieties included DP555BR, FM991R, and
DP444BR. Replanted areas amounted to possibly 20% of the total test area and appeared to ‘catch up’ with
the originally planted cotton.
A summary of plant measurement trends are found in Figures 1, 2, and 3. Height to node ratio trends for
each of the twelve varieties are shown in Figure 1. Minor differences were observed among the varieties
with DP555BR and SCX-7 exhibiting lower levels of plant vigor towards the latter part of the season.
Overall vigor of the test was less than average in part because of the high level of fruit load carried by the
crop, particularly early in the season (Figure 2). Fruit retention levels remained above 80% until toward the
end of July when levels dropped to an average of 65%. No major differences in fruit load were observed
among any of the twelve varieties in this evaluation.
All fiber quality data is presented in Figures 4 and 5. Discounts for low micronaire were applied to three of
the twelve varieties in the evaluation (Figure 4B). All varieties received premiums for fiber strength except
one (Figure 4C). All varieties were in the premium range for staple length (Figure 5A). The variety
evaluation was harvested at a time when many of the varieties still had a significant amount of green leaves
remaining on the plant resulting in all but three of the varieties receiving discounts for leaf grade (Figure
Arizona Cotton Report (P-142) May 2005
116
5C). Figure 6A shows the premium received for each of the varieties. The FiberMax and Acala varieties
received the highest premium of approximately $0.04/pound. Crop value was calculated using the
premium/discount which was added to the base loan rate of $0.52/pound and multiplied by the total lint
yield. Figure 6B shows the total crop value for each of the twelve varieties. Lint yield is presented in
Figure 6C. Lin yield average from 1200 to over 1600 lbs. lint/acre. FiberMax variety FM991BR
performed extremely well again this year not only having the highest yield but because of the high fiber
quality it also had the highest total crop value.
Kansas Settlement
Table 3 lists the end of season plant measurements collected for each of the 15 varieties included in the
evaluation. Data collected included plant population, plant height, first fruiting branch, total mainstem
nodes, and average seedcotton weight per boll.
Wide variation in fiber quality was observed among the varieties in this evaluation. Several varieties fell
into the discount range for low micronaire with a range in micronaire from 3.1 to over 4.0 (Figure 7B).
This evaluation had more pronounced differences among the Upland and Acala varieties. Figure 8A shows
the increase in staple length for the Acala varieties. The two New Mexico varieties had high fiber
uniformity (Figure 8B). All varieties in this evaluation received premiums for fiber quality except one
(Figure 9A). Lint yields ranged from 650 to over 1200 lbs lint/acre (Figure 9C) with the Stoneville variety
ST5242BR producing the highest lint yield. However due to the lower fiber quality, the high yielding
variety did not produce the highest crop value (Figure 9B). The three Acala varieties produced the highest
crop values (Sierra, Riata, and C103). This evaluation provides an excellent example of the fact that high
fiber quality can make up for some decline in yield.
Arizona Cotton Report (P-142) May 2005
117
Table 1. Listing of varieties with corresponding maturity ratings and transgenic traits included in the
Graham County variety evaluation in Thatcher, AZ, 2004.
Variety
Company
Maturity Rating
Genetic Traits
ST5242BR
Stoneville
Early-Medium
BG, RR
Sierra
CPSCD
Medium-Full
RR
Riata
CPCSD
Medium-Full
RR
ST5599BR
Stoneville
Medium
BG, RR
ST4646B2R
Stoneville
Early-Medium
BGII, RR
DP555BR
Deltapine
Medium-Full
BG, RR
DP655BR
Deltapine
Medium-Full
BG, RR
DP444BR
Deltapine
Early
BG, RR
DP488BR
Deltapine
Medium
BR, RR
SCX-7
Salcot
Medium-Full
--FM989BR
FiberMax
Medium
BG, RR
FM991BR
FiberMax
Full
BG, RR
Table 2. Listing of varieties with corresponding maturity ratings and transgenic traits included in the
Cochise County variety evaluation in Kansas Settlement, AZ, 2004.
Variety
Company
Maturity Rating
Genetic Traits
ST5242BR
Stoneville
Early-Medium
BG, RR
Sierra
CPSCD
Medium-Full
RR
Riata
CPCSD
Medium-Full
RR
C-103
CPCSD
Medium-Full
--ST5599BR
Stoneville
Medium
BG, RR
ST4646B2R
Stoneville
Early-Medium
BGII, RR
DP432BR
Deltapine
Early
BG, RR
DP449BR
Deltapine
Medium
BG, RR
DP444BR
Deltapine
Early
BG, RR
SCX-7
Salcot
Medium-Full
--FM960BR
FiberMax
Early-Medium
BG, RR
FM991BR
FiberMax
Full
BG, RR
1517-99
NMSU
Medium-Full
--1517-95
NMSU
Medium-Full
---
Arizona Cotton Report (P-142) May 2005
118
2.5
2.5
Sierra
DP488BR
DP555BR
DP444BR
DP655BR
FM989BR
2.0
Height (in.)/Node Ratio
Height (in.)/Node Ratio
2.0
FM991BR
FM991R
ST5242BR
SCX_7
ST4646B2R
ST5599BR
1.5
1.0
0.5
1.5
1.0
0.5
0.0
0.0
500
1000
1500
2000
2500
3000
Heat Units Accumulated After Planting (HUAP)
3500
500
1000
1500
2000
2500
3000
3500
Heat Units Accumulated After Planting (HUAP)
Figure 1. Height (in.) to node ratio trends for each of the twelve varieties included in the Graham County variety evaluation in Thatcher, AZ, 2004.
Arizona Cotton Report (P-142) May 2005
119
120
120
Sierra
DP488BR
DP555BR
DP444BR
DP655BR
FM989BR
80
100
Percent Fruit Retention
Percent Fruit Retention
100
FM991BR
FM991R
ST5242BR
SCX_7
ST4646B2R
ST5599BR
60
40
20
80
60
40
20
0
0
500
1000
1500
2000
2500
3000
Heat Units Accumulated After Planting (HUAP)
3500
500
1000
1500
2000
2500
3000
3500
Heat Units Accumulated After Planting (HUAP)
Figure 2. Percent fruit retention trends for each of the twelve varieties included in the Graham County variety evaluation in Thatcher, AZ, 2004.
Arizona Cotton Report (P-142) May 2005
120
18
18
Nodes Above Top Fresh Bloom
14
12
10
8
6
4
2
0
16
Nodes Above Top Fresh Bloom
Sierra
DP488BR
DP555BR
DP444BR
DP655BR
FM989BR
16
FM991BR
FM991R
ST5242BR
SCX_7
ST4646B2R
ST5599BR
14
12
10
8
6
4
2
0
500
1000
1500
2000
2500
3000
Heat Units Accumulated After Planting (HUAP)
3500
500
1000
1500
2000
2500
3000
3500
Heat Units Accumulated After Planting (HUAP)
Figure 3. Number of nodes above top fresh bloom trends for each of the twelve varieties included in the Graham County variety evaluation in Thatcher, AZ,
2004.
Arizona Cotton Report (P-142) May 2005
121
Table 3. Summary of plant measurement data collected from the Cochise County variety evaluation in
Kansas Settlement, AZ, 2004.
Plant
Plant
First Fruiting
Mainstem
Average Boll
Variety
Population
Height
Branch
Nodes
Weight
1517_95
36363.64
22.25
7.25
18.25
5.44
1517_99
39090.91
28.00
7.75
19.50
5.70
C103
35909.09
29.50
7.25
17.25
5.58‚
DP432BR
47727.27
24.00
6.25
15.75
4.80
DP444BR
46363.64
28.00
6.25
17.25
5.16
DP449BR
51818.18
30.25
5.50
19.00
4.90
FM960BR
44363.64
24.80
6.70
17.40
5.90
FM991BR
59090.91
24.25
7.25
17.75
5.22
Riata
41818.18
33.25
6.50
19.25
5.53
S4646B2R
36818.18
29.75
7.50
18.00
5.50
SCX7
46363.64
25.50
5.50
18.75
5.11
Sierra
44090.91
27.75
6.00
15.50
5.69
ST5242BR
30909.09
27.25
6.75
16.50
5.83
ST5599BR
44545.45
27.50
5.50
16.75
5.71
Arizona Cotton Report (P-142) May 2005
122
Discount
DP555BR
LSD = 0.0304
C.V. = 5.86
OSL = <0.0001
abcd
DP444BR
abc
ST4646B2R
d
Sierra
cd
DP655BR
cd
A
SCX-7
0.35
cde
a
FM991R
abcd
0.40
0.45
B
abcde
DP655BR
FM991BR
a
0.30
bcde
FM989BR
FM991BR
0.25
ab
DP488BR
bcd
FM991R
abcde
Sierra
e
FM989BR
abc
ST5599BR
bcd
SCX-7
de
ST5242BR
cd
DP488BR
e
DP444BR
bcd
ST5599BR
LSD = 0.27
C.V. = 5.33
OSL = 0.0186
de
DP555BR
ab
ST5242BR
0.20
ST4646B2R
abcde
3.0
3.2
3.4
Percent Lint
3.6
3.8
4.0
Micronaire
Premium
Figure 4. Statistical means separation
and analysis of variance results for A)
percent lint, B) micronaire, and C)
fiber strength for the twelve varieties
included in the Graham County variety
evaluation in Thatcher, AZ, 2004.
Means followed by the same letter are
not significantly different according to
a Fisher’s least significant difference
means separation test.
LSD = Least Significant Difference
CV = Coefficient of Variation
OSL = Observed Significance Level
ST4646B2R
a
DP555BR
a
DP444BR
LSD = 2.39
C.V. = 5.55
OSL = 0.1034
a
ST5242BR
a
ST5599BR
C
a
Sierra
a
DP488BR
a
a
SCX-7
FM989BR
a
FM991R
a
a
DP655BR
FM991BR
a
28
29
30
31
32
33
Fiber Strength (g/tex)
Arizona Cotton Report (P-142) May 2005
123
Discount
Premium
ST4646B2R
cde
DP555BR
bc
DP444BR
LSD = 1.13
C.V. = 2.23
OSL = <0.0001
ST4646B2R
DP555BR
Sierra
SCX-7
ab
c
FM989BR
bc
FM991R
bcd
abc
DP655BR
FM991BR
ab
36
B
abc
FM991R
A
FM991BR
34
a
SCX-7
a
de
32
ab
DP488BR
a
DP655BR
abc
Sierra
bc
DP488BR
30
ab
ST5599BR
e
FM989BR
ab
ST5242BR
cde
ST5599BR
bc
DP444BR
dc
ST5242BR
LSD =1.01
C.V. = 0.88
OSL = 0.0032
c
38
40
a
80.0
80.5
81.0
Staple Length (32nd inch)
81.5
82.0
82.5
Uniformity Index (%)
Discount
Figure 5. Statistical means separation
and analysis of variance results for A)
staple length, B) uniformity index, and
C) leaf grade for the twelve varieties
included in the Graham County variety
evaluation in Thatcher, AZ, 2004.
Means followed by the same letter are
not significantly different according to
a Fisher’s least significant difference
means separation test.
LSD = Least Significant Difference
CV = Coefficient of Variation
OSL = Observed Significance Level
ST4646B2R
a
LSD = 0.64
C.V. = 12.65
a OSL = 0.0001
c
DP555BR
DP444BR
bc
ST5242BR
ST5599BR
a
Sierra
bc
DP488BR
a
ab
SCX-7
C
c
FM989BR
c
FM991R
DP655BR
ab
FM991BR
ab
2.6
2.8
3.0
3.2
3.4
3.6
3.8
4.0
4.2
4.4
Leaf Grade
Arizona Cotton Report (P-142) May 2005
124
ST4646B2R
LSD = 2.23
C.V. = 53.83
OSL = 0.0312
d
DP555BR
abc
DP444BR
ST4646B2R
DP555BR
bcd
DP444BR
ST5242BR
A
abc
ST5242BR
cd
ST5599BR
ST5599BR
Sierra
a
DP488BR
Sierra
abc
SCX-7
DP488BR
abc
abc
FM989BR
FM989BR
ab
FM991R
FM991R
abc
DP655BR
DP655BR
FM991BR
ab
0
1
2
B
SCX-7
3
FM991BR
4
5
500
600
Premium/Discount (cents/lb.)
Figure 6. Statistical means separation
and analysis of variance results for A)
premium/discount, B) total crop value,
and C) lint yield for the fourteen
varieties included in the Graham
County variety evaluation in Thatcher,
AZ, 2004. Means followed by the
same letter are not significantly
different according to a Fisher’s least
significant
difference
means
separation test.
LSD = Least Significant Difference
CV = Coefficient of Variation
OSL = Observed Significance Level
800
900
1000
Value ($/acre)
ST4646B2R
LSD = 90.9
C.V. = 4.7
OSL = <0.0001
h
DP555BR
gh
DP444BR
fgh
ST5242BR
fgh
ST5599BR
efg
Sierra
C
defg
DP488BR
def
SCX-7
cde
FM989BR
cd
FM991R
bc
DP655BR
ab
FM991BR
1000
700
a
1100
1200
1300
1400
1500
1600
1700
Lint Yield (lbs./acre)
Arizona Cotton Report (P-142) May 2005
125
Disocunt
f
1517_95
bcde
SCX7
LSD = 0.26
C.V. = 4.6
OSL = <0.0001
def
FM960BR
b
cde
SCX7
f
DP444BR
f
A
cdef
DP449BR
bc
ST5599BR
a
RIATA
bcd
a
ST5242BR
0.36
0.38
0.40
0.42
ef
C103
abc
RIATA
ef
SIERRA
ef
b
0.34
a
ab
S4646B2R
C103
SIERRA
g
DP432BR
bcde
ST5599BR
ab
DP449BR
bcd
DP432BR
S4646B2R
0.32
def
FM991BR
FM960BR
DP444BR
bcd
1517_99
def
FM991BR
0.30
1517_95
LSD = 0.03
C.V. = 4.87
OSL = <0.0001
ef
1517_99
bcd
ST5242BR
0.44
3.0
0.46
3.2
3.4
3.6
3.8
4.0
4.2
Micronaire
Percent Lint
Discount
Figure 7. Statistical means separation
and analysis of variance results for A)
percent lint, B) micronaire, and C)
fiber strength for the fourteen varieties
included in the Cochise County variety
evaluation in Kansas Settlement, AZ,
2004. Means followed by the same
letter are not significantly different
according to a Fisher’s least
significant
difference
means
separation test.
LSD = Least Significant Difference
CV = Coefficient of Variation
OSL = Observed Significance Level
B
Premium
b
1517_95
a
1517_99
LSD = 1.17
C.V. = 2.52
OSL = <0.0001
cd
FM991BR
FM960BR
c
SCX7
e
DP444BR
e
C
cde
DP449BR
DP432BR
f
S4646B2R
f
ST5599BR
de
C103
c
b
RIATA
cde
SIERRA
ST5242BR
g
24
26
28
30
32
34
36
38
Fiber Strength (g/tex)
Arizona Cotton Report (P-142) May 2005
126
Discount
Premium
Premium
b
1517_95
a
1517_99
FM991BR
LSD = 0.83
C.V. = 1.52
OSL = <0.0001
cd
FM960BR
ef
SCX7
de
DP449BR
de
DP432BR
bc
ab
DP449BR
ab
DP432BR
A
bc
RIATA
bc
SIERRA
g
ab
S4646B2R
bc
ST5599BR
bc
C103
bc
b
ST5242BR
RIATA
ab
SIERRA
ab
ST5242BR
30
32
34
LSD = 1.36
C.V. = 1.07
OSL = 0.0025
bc
SCX7
ed
C103
fgh
DP444BR
ef
ST5599BR
a
FM960BR
f
S4646B2R
a
1517_99
FM991BR
de
DP444BR
1517_95
36
38
40
B
bc
79
80
81
Staple Length (32nd inch)
82
83
84
Uniformity Index (%)
Discount
Figure 8. Statistical means separation
and analysis of variance results for A)
staple length, B) uniformity index, and
C) leaf grade for the fourteen varieties
included in the Cochise County variety
evaluation in Kansas Settlement, AZ,
2004. Means followed by the same
letter are not significantly different
according to a Fisher’s least
significant
difference
means
separation test.
LSD = Least Significant Difference
CV = Coefficient of Variation
OSL = Observed Significance Level
a
1517_95
c
1517_99
LSD = 0.604
C.V. = 13.64
OSL = <0.0001
d
FM991BR
FM960BR
c
SCX7
c
DP444BR
c
DP449BR
c
DP432BR
c
C
c
S4646B2R
c
ST5599BR
C103
c
RIATA
c
c
SIERRA
d
ST5242BR
1
2
3
4
5
Leaf Grade
Arizona Cotton Report (P-142) May 2005
127
1517_95
LSD = 1.64
C.V. = 32.13
OSL = <0.0001
1517_95
1517_99
1517_99
ab
FM991BR
a
FM960BR
SCX7
ab
SCX7
DP444BR
cd
DP449BR
ab
DP444BR
DP449BR
B
FM960BR
a
FM991BR
DP432BR
d
S4646B2R
abc
DP432BR
ST5599BR
bc
S4646B2R
A
abc
ST5599BR
C103
ab
C103
RIATA
SIERRA
a
RIATA
SIERRA
ST5242BR
ab
e
ST5242BR
200
-2
-1
0
1
2
3
4
5
300
6
400
500
600
700
Value ($/acre)
Premium/Discount (cents/lb.)
Figure 9. Statistical means separation
and analysis of variance results for A)
premium/discount, B) total crop value,
and C) lint yield for the fourteen
varieties included in the Cochise
County variety evaluation in Kansas
Settlement, AZ, 2004.
Means
followed by the same letter are not
significantly different according to a
Fisher’s least significant difference
means separation test.
LSD = Least Significant Difference
CV = Coefficient of Variation
OSL = Observed Significance Level
e
1517_95
LSD = 183.92
C.V. = 12.02
OSL = <0.0001
e
1517_99
de
FM991BR
FM960BR
cd
SCX7
cd
C
bcd
DP444BR
DP449BR
abc
DP432BR
abc
abc
S4646B2R
ab
ST5599BR
C103
ab
RIATA
ab
SIERRA
ab
a
ST5242BR
600
700
800
900
1000
1100
1200
1300
Lint Yield (lbs./acre)
Arizona Cotton Report (P-142) May 2005
128