Effect of Varying Levels of Boll Feeding Bug Damage on Fiber Quality

1
Effect of Varying Levels of Boll Feeding Bug
Damage on Fiber Quality

• P. Roberts, A. Knowlton, and J Ruberson (UGA)
• J. Bacheler, D. Mott, D. Morrison, T. Pegram
  (NCSU)
• J. Greene, D. Robinson, T. Walker, S. Turnipseed,
  M. Sullivan (Clemson)
• R. Smith (Auburn), C. Bednarz (TTU)

2
Stink Bug Feeding

• Piercing and sucking mouthpart.
• Feeds primarily on fruiting structures and
  meristematic tissues (seed and surrounding
  tissues in cotton bolls).
• Injects digestive enzymes.
• Extracts dissolved plant tissue and sap.
• Physical destruction of seed (lint production
  reduced).
• Introduces or allows entry (wounds) of pathogens
  and decay organisms.

3
Prefer medium sized bolls Small bolls shed Large
bolls remain on the plant Susceptible lt25 days of
age (yield)
4
Fiber Development StagesElongation / Secondary
Wall Deposition
5
L(w) in (Treated Untreated) All Locations,
hand-picked by position
AFIS Cotton Incorporated
6
Picker Efficiency of damaged bolls?
7
Lint cleaners, other ginning processes?
8
Objective and Methods

• Quantify the impact of bug damage on fiber
  quality.
• 24 field trials established in GA, NC, SC, AL
  (2005)
• Untreated vs. Bug Treated
• Intermediate Treatments
• Threshold
• Progressive Protection
• Machine-Picked Cotton
• Simulate Commercial Ginning (UGA MicroGin)
• HVI, AFIS (Cotton Incorporated)
• Large data set with a range of bug damage.
• Compared differences in quality values with most
  aggressive treatment in a given trial.
• Grouped differences of treatment means from
  individual trials by yield loss (assumed yield
  loss due to bug damage).

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2005 SE Regional Stink Bug ProjectUGA MicroGin
mean8.308
n23
n6
n14
n22
n7
n7
HVI and AFIS Cotton Incorporated N24
locations, 103 treatments (79 comparisons)
10
2005 SE Regional Stink Bug ProjectUGA MicroGin
mean35.93
n23
n6
n14
n22
n7
n7
HVI and AFIS Cotton Incorporated N24
locations, 103 treatments (79 comparisons)
11
2005 SE Regional Stink Bug ProjectUGA MicroGin
mean81.95
n23
n6
n14
n22
n7
n7
HVI and AFIS Cotton Incorporated N24
locations, 103 treatments (79 comparisons)
12
2005 SE Regional Stink Bug ProjectUGA MicroGin
mean0.985
n23
n6
n14
n22
n7
n7
HVI and AFIS Cotton Incorporated N24
locations, 103 treatments (79 comparisons)
13
2005 SE Regional Stink Bug ProjectUGA MicroGin
mean34.42
n23
n6
n14
n22
n7
n7
HVI and AFIS Cotton Incorporated N24
locations, 103 treatments (79 comparisons)
14
2005 SE Regional Stink Bug ProjectUGA MicroGin
mean9.030
n23
n6
n14
n22
n7
n7
HVI and AFIS Cotton Incorporated N24
locations, 103 treatments (79 comparisons)
15
UGA Micro-Gin (HVI) 2005Stink Bug Trials, GA,
SC, and AL
2005 Untreated 20 Percent Threshold Aggressively Sprayed
Lint/acre 760 a 1125 b 1232 b
Lint 34.93 a 36.21 b 36.25 b
MIC 4.27 a 4.37 b 4.43 b
UHM (32nds) 35.62 a 36.01 b 36.03 b
UI 81.18 a 81.63 b 81.60 b
STR 30.08 a 29.97 a 30.06 a
Rd 75.37 a 76.81 b 77.23 b
b 9.04 a 8.46 b 8.25 b
HVI Cotton Incorporated N11 locations (trial
means analyzed as reps)
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UGA Micro-Gin (AFIS) 2005Stink Bug Trials, GA,
SC, and AL
2005 Untreated 20 Percent Threshold Aggressively Sprayed
Nep size (um) 703.4 a 692.6 b 691.5 b
Neps per Gm 308.9 a 255.2 b 244.0 b
L(w) in 0.9542 a 0.9734 b 0.9806 b
L(w) CV 36.65 a 35.51 b 35.11 b
UQL (w) in 1.180 a 1.192 b 1.199 b
SFC (w) 11.21 a 10.02 b 9.61 b
L (n) in 0.6894 a 0.7204 b 0.7304 b
L (n) CV 62.09 a 59.40 b 58.57 b
SFC (n) 36.41 a 33.53 b 32.57 b
L5 (n) in 1.321 a 1.337 b 1.343 b
AFIS Cotton Incorporated N11 locations (trial
means analyzed as reps)
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UGA Micro-Gin (AFIS) 2005Stink Bug Trials, GA,
SC, and AL
2005 Untreated 20 Percent Threshold Aggressively Sprayed
Total Cnt/g 413.0 a 322.2 b 293.7 b
Trash Size um 360.7 a 364.2 a 366.8 a
Dust Cnt/g 332.1 a 257.8 b 233.9 b
Trash Cnt/g 80.55 a 64.07 b 59.45 b
VFM 1.702 a 1.325 b 1.212 b
SCN Size (um) 1065 a 1073 a 1084 a
SCN (Cnt/g) 23.86 a 17.50 b 16.79 b
Fine mTex 172.9 a 173.8 ab 175.6 b
IFC 5.359 a 5.016 b 4.820 b
Mat Ratio 0.9148 a 0.9214 ab 0.9274 b
AFIS Cotton Incorporated N11 locations (trial
means analyzed as reps)
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Identifying Practical Knowledge and Solutions
for Managing The Sucking-Bug Complex In Cotton
Research In The Southeast Region
Southeast State Support Committees