C'W' Bednarz and W'D' Shurley

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Losses in Yield, Quality, and Profitability of
Cotton From Improper Harvest Timing
C.W. Bednarz and W.D.
Shurley University of Georgia and W.S.
Anthony USDA-ARS
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http//www.cottoninc.com/online/index.cfm
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http//www.cottoninc.com/online/index.cfm
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IS THIS PROBLEM DUE TO

• ENVIRONMENT?
• Soil Type
• MANAGEMENT?
• Varieties
• Population Densities
• Insect Control
• Harvest Timing

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PERCENT HARVESTED BY WEEK(5 year
average)http//www.nass.usda.gov
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Cotton and Peanut Most Active Planting and
Harvest Dates http//www.nass.usda.gov
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What is This Harvest Delay Costing
Us?(Objectives of Study)

• Investigate the effects of harvest timing on
  fiber properties in general and percent
  uniformity in particular.
• Investigate the effects of harvest timing on lint
  yield.
• Investigate the effects of harvest timing on
  profitability.

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Cotton Defoliation Timing Study CPES - Ponder
Farm

• Established 13 treatments (weeks) in the study
  area.
• Applied harvest aids every week for 13 weeks
  (NACB and OB)
• Machine picked each plot two weeks after applying
  harvest aids.

• Seed cotton ginned on mini gin and the USDA-ARS
  Lab.
• HVI and AFIS on lint samples (3 per plot).
• Data subject to ANOVA.

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Harvest Dates
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(No Transcript)
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Uniformity 1998
a
a
a
a
a
a
a
a
ab
ab
ab
ab
b
PgtF 0.0929
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Uniformity 1999
a
ab
abc
abc
bcd
bcd
bcd
cd
cd
cd
cd
de
e
PgtF 0.0026
13
Uniformity 2000
ab
a
ab
abc
bc
bc
cd
cd
d
d
d
d
d
PgtF 0.0017
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L(n)CV 1999
a
a
ab
ab
ab
bc
bc
c
c
c
c
c
c
F 4.17
15
L(n)CV 2000
a
a
ab
ab
abc
abc
bc
bcd
cde
cde
de
e
e
F 6.19
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Why is Uniformity Changing?

• Increasing up to 70 OB
• Crop Maturity?
• Non-determinate Crop
• Decreasing after 70 OB
• Crop Weathering?

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Strength 1998
a
b
bc
c
c
cde
cde
cd
def
de
ef
f
f
PgtF 0.0001
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Strength 1999
ab
a
a
ab
ab
abc
bc
bc
cd
d
d
d
d
PgtF 0.0001
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Strength 2000
a
a
b
bc
bcd
cdef
bcde
def
efg
fg
fg
fg
g
F 13.91
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HVI-UHM 1998
a
a
a
a
a
a
a
a
a
a
a
a
a
PgtF 0.1699
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HVI-UHM 1999
a
a
a
a
a
a
a
a
a
a
a
a
a
PgtF 0.0833
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HVI-UHM 2000
a
ab
abc
abc
abc
abc
bcde
bcde
def
cdef
def
f
f
F 3.94
23
AFIS-Length(n) 1999
a
a
a
a
a
ab
abc
bcd
bcd
bcd
bcd
cd
d
PgtF 0.0006
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AFIS-Length(n) 2000
a
ab
cd
abc
bcd
cd
de
efg
defg
defg
fg
g
g
F 8.70
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AFIS-SFC(w) 1999
abc
ab
a
abc
abc
abcd
bcd
bcd
cd
d
d
d
d
PgtF 0.0071
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AFIS-SFC(n) 2000
a
a
ab
abc
bcd
bc
cde
def
def
efg
fg
fg
g
F 9.24
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HVI Micronaire 1998
a
ab
a
ab
ab
ab
ab
ab
a
ab
bc
c
c
PgtF 0.0011
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HVI Micronaire 1999
abc
abc
abc
abc
abc
ab
ab
bcd
cd
d
a
e
e
PgtF 0.0001
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HVI Micronaire 2000
bcde
bcd
bc
a
bc
bcde
ab
ab
e
cde
de
f
g
F 59.40
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Rainfall During Harvest
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Color Grades
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Sum of Premiums/Discounts
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Lint Yields
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CONCLUSIONSApplication of Harvest-Aids at 60-80
Open Boll

• Maximized
• Length Uniformity
• Fiber Length
• Lint Yield (1999)
• Profit (1999)
• Minimized
• Short Fiber Content