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Alternatives….
Alternatives….
Carol Jones, PhD, PE, Oklahoma State Universityarol Jones, PhD, PE, Oklahoma State UniversityStored Products Research and Education CenterStored Products Research and Education Center
Missouri Fumigation TrainingJanuary 10 – 11, 2010
We have…..
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We have…AlternativesWe have…Alternatives
Missouri Fumigation TrainingJanuary 10 – 11, 2010
Reasons for alternative methods for controlling insects…maintaining grain quality
• Insect resistance
• Customer request (organics, social, marketing)
• Environmental concerns
• Safety
• Governmental regs
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We have…AlternativesWe have…Alternatives
Missouri Fumigation TrainingJanuary 10 – 11, 2010
Methods…
• Aeration
• Ozone
• Heat Treatment
• Ethylene….”Apple Gas”
What does aeration do?
• Little insect reproduction occurs below 60F
• Eggs are controlled at 40F
• 40F is tough to do in some areas
• So fumigation is still required but can be reduced
Carol Jones, PhD.Stored Product EngineeringBiosystems and Ag. Engr. Dept.
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We have…AlternativesWe have…Alternatives
Missouri Fumigation TrainingJanuary 10 – 11, 2010
• Little insect reproduction occurs below 60F
• Eggs are controlled at 40F
• 40F is tough to do in some areas
• So fumigation is still required but can be reduced
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You have…AlternativesYou have…Alternatives
Missouri Fumigation TrainingJanuary 10 – 11, 2010
Electrical Generation of Ozone
• Attractive alternative• Eliminates some of the concerns
– No residues because degradation product is oxygen
– No transportation of product– No storage issues
Objectives• Determine the effectiveness of ozone
fumigation on six stored product pests in a grain mass of wheat under field conditions during the month of October, the traditional time during storage when grain is fumigated in Oklahoma
Experimental Protocol
• Conducted in October 2007• Steel grain bins contained
13.6 metric tons of hard red winter wheat
• One bin treated; one bin control
• Grain was poor quality because of extreme wet conditions at end of growing season
Ozone Generator
• OZAT Model CFS-3A• Operated at 30 g/hr• Produced three targeted
ozone concentrations of 25, 50, and 70 ppm within the bin
Ozone Introduced into Bin
• Through a 6.4 mm tube from generator just upstream of fan into a 10.2 cm pipe connected to the aeration fan transition into the bottom of the bin
• Axial fan moved 0.21 cubic meters/sec of air/ozone through grain mass
• Ozone concentration decreased as it moved through the grain mass
Insect Sampling Tubes
• Tubes of 10.2 cm diameter were inserted into bins at depths corresponding to targeted ozone levels
• Ozone rose through the tubes to come in contact with bags containing insects
• A recirculation system was used to recover ozone exiting the top of the grain mass and then injected back into the bottom of the bin through a closed loop system
• Ozone concentrations monitored every 8 hrs
Rhyzopertha dominicaLesser Grain Borer
Plodia interpunctellaIndianmeal Moth
Tribolium castaneumRed Flour Beetle
Sitophilus oryzaeRice Weevil
Oryzaephilus surinamensisSawtoothed Grain Beetle
Insects Evaluated
Cryptolestes ferrugineusRusty Grain Beetle
Insect Samples• 7.0 x 10.2 cm cotton muslin
tea bags with drawstring• Bags placed in bins for 1, 2,
3, and 4 days exposure• Beetle adults and P.
interpunctella larvae were assessed upon removal
• All grain particles and dust placed in 226.8 g glass jars and held at 28°C
• P. interpunctella eggs evaluated after 1 week and pupae after 2 weeks
• Beetle progeny counted at 2 and 4 weeks
Percent Mortality for P. interpunctella (Indian Meal Moth)
0
20
40
60
80
100
1-day 2-day 3-day 4-day
% M
ort
alit
y
None Low Medium High
Eggs
0
20
40
60
80
100
1-day 2-day 3-day 4-day
% M
ort
alit
y
None Low Medium High
Pupae
0
20
40
60
80
100
1-day 2-day 3-day 4-day
% M
ort
alit
y
None Low Medium High
Larvae
Percent Mortality Mean No. Progeny
Eggs
0
20
40
60
80
100
1-day 2-day 3-day 4-day
% M
ort
alit
y
None Low Medium High
0
20
40
60
80
100
1-day 2-day 3-day 4-day
% M
ort
alit
y
None Low Medium High
0
50
100
150
200
1-day 2-day 3-day 4-day
Mea
n N
um
ber
of
Pro
gen
y
None Low Medium High
0
50
100
150
200
250
300
1-day 2-day 3-day 4-day
Mea
n N
um
ber
of
Pro
gen
y
None Low Medium High
R. dominica: LGB
S. oryzae: rice weevil
Percent Mortality Mean No. Progeny
EggsR. dominica R. dominica
S. oryzae S. oryzae
0
20
40
60
80
100
1-day 2-day 3-day 4-day
% M
ort
alit
y
None Low Medium High
0
20
40
60
80
100
1-day 2-day 3-day 4-day
% M
ort
alit
y
None Low Medium High
0
25
50
75
100
125
1-day 2-day 3-day 4-day
Mea
n N
um
ber
of
Pro
gen
y
None Low Medium High
0
20
40
60
80
100
1-day 2-day 3-day 4-day
Mea
n N
um
ber
of
Pro
gen
y
None Low Medium High
T. castaneum:Red flour beetle
T. castaneum
C. ferrugineus:Rusty Grain Beetle
C. ferrugineus
0
20
40
60
80
100
1-day 2-day 3-day 4-day
% M
ort
alit
y
None Low Medium High
Percent Mortality Mean No. Progeny
0
100
200
300
400
1-day 2-day 3-day 4-day
Mea
n N
um
ber
of
Pro
gen
y
None Low Medium High
O. surinamensis: Sawtoothed grain beetle
• Eggs and larvae of Indianmeal Moth were only moderately controlled and pupae were the most sensitive to ozone treatments
• Overall, adult beetle mortality increased with increasing time of exposure although 100% mortality was only realized for Rice Weevil and Red Flour Beetle
• Total suppression of progeny production was only seen for Red Flour Beetle at the high ozone concentration
• To obtain total control, either the ozone concentration should be increased or the time of exposure increased
We have…AlternativesWe have…Alternatives
Missouri Fumigation TrainingJanuary 10 – 11, 2010
Using Heat to Disinfest Concrete Silos
Missouri Fumigation TrainingJanuary 10 – 11, 2010
Using Heat to Kill Insects
• Attractive alternative• Eliminates some of the concerns
– No residues – No transportation of product; heat generated on-site– No storage issues of dangerous chemicals– Shorter down-time
Missouri Fumigation TrainingJanuary 10 – 11, 2010
Day 1Heat
Day 3Control
Day 3Heat
Day 2Control
Day 2Heat
Day 1Control
Bin Selection for Heating Study
Rhyzopertha dominicaLesser Grain Borer
Tribolium castaneumRed Flour Beetle
Insects Evaluated
Psocids
Bin 1-Top
0
20
40
60
80Ambient AirRFB ContainerLGB ContainerPsocid Container
Bin 1-33' Down From Top
0
20
40
60
80
Bin 1-66' Down From Top
Tem
pera
ture
°C
0
20
40
60
80
Bin 1-Bottom
0
20
40
60
80
0900 1100 1300 1500
0
25
50
75
100
Heat Control
Top 33' down 66' down Bottom
Percent Survival of RFB Adults
0
25
50
75
100
Heat Control
Top 33' down 66' down Bottom
Percent Survival of LGB Adults
0
25
50
75
100
125
Heat Control
Top 33' down 66' down Bottom
Progeny Production of RFB
0
50
100
150
200
250
300
350
Heat Control
Top 33' down 66' down Bottom
Progeny Production of LGB
0
25
50
75
100
Heat Control
Top 33' down 66' down Bottom
Percent Adult Survival of L. decolor
0
25
50
75
100
Heat Control
Top 33' down 66' down Bottom
Percent Adult Survival of L. corrodens
Propane Usage
• Average of 76 gallons propane per 99’ silo
• Cost per gallon was $3.00 on May 1, 2008• Total cost per silo was $228.00
– Equivalent phosphine pellets to treat silo• 4,000 – 18,000 pellets per silo• $34.30 - $155.05 based on a cost of $300
per case of 21 flasks of pellets
Missouri Fumigation TrainingJanuary 10 – 11, 2010
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We have…AlternativesWe have…Alternatives
Missouri Fumigation TrainingJanuary 10 – 11, 2010
• Ethylene “apple gas”• Background and idea
•ANG in Afghanistan• Early testing
•Killed insects• Predictions
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We have…AlternativesWe have…Alternatives
Missouri Fumigation TrainingJanuary 10 – 11, 2010
• Manage through IPM• Identify your insects• Keep informed of new
methods being tested and results
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We have…AlternativesWe have…Alternatives
Carol Jones, PhD, PE, Oklahoma State Universityarol Jones, PhD, PE, Oklahoma State UniversityStored Products Research and Education CenterStored Products Research and Education Center
Missouri Fumigation TrainingJanuary 10 – 11, 2010
Questions
