Stored Seed Protectants Bhadriraju Subramanyam (Subi) Department of Grain Science and Industry Kansas State University Manhattan, KS 66506 [email protected].

Stored Seed Protectants Stored Seed Protectants

Bhadriraju Subramanyam (Subi)Bhadriraju Subramanyam (Subi)Department of Grain Science and IndustryDepartment of Grain Science and Industry

Kansas State UniversityKansas State UniversityManhattan, KS 66506Manhattan, KS 66506

[email protected]@ksu.eduwww.oznet.ksu.edu/grsc_subiwww.oznet.ksu.edu/grsc_subi

ASTA Seed Treatment & Environmental Committee MeetingASTA Seed Treatment & Environmental Committee MeetingJuly 12, 2006July 12, 2006

Insects in stored seedInsects in stored seed(Internal)(Internal)

ExternalExternal

Losses caused by insectsLosses caused by insects

Quantitative losses, 5-10%Quantitative losses, 5-10%Seed heating (contributes to Seed heating (contributes to

moisture migration) moisture migration) Distribute molds within seed bulkDistribute molds within seed bulkSome species feed exclusively on the Some species feed exclusively on the

germgerm

Management of stored-product insectsManagement of stored-product insects

Keep storage areas free of insectsKeep storage areas free of insectsSeed treatmentsSeed treatments

Preventive approaches-prevents infestationPreventive approaches-prevents infestationCold storageCold storageAerationAerationUse of seed protectantsUse of seed protectants

Responsive approaches-cannot prevent Responsive approaches-cannot prevent reinfestationreinfestationFumigation-Phosphine, sulfuryl fluorideFumigation-Phosphine, sulfuryl fluorideModified atmospheresModified atmospheresHeat (from various sources)Heat (from various sources)

Pneumatic conveying kills 80-90% of the insects that are external feedersPneumatic conveying kills 80-90% of the insects that are external feeders

Temperature effects on stored-Temperature effects on stored-product insectsproduct insects

Te

mp

era

t ure

(°C

)

Te

mp

era

ture

(°F

)

-30

-20

-10

0

10

20

30

40

50

60

70

-20

0

20

40

60

80

100

120

140

Source: Fields (1992)Source: Fields (1992) 55oF or below

Seed protectantsSeed protectantsPirimiphos-methyl – corn and sorghum (8 ppm)Pirimiphos-methyl – corn and sorghum (8 ppm)Diacon II (Methoprene) (1. 2.5 and 5 ppm)Diacon II (Methoprene) (1. 2.5 and 5 ppm)

Wheat, corn, sorghum, barley, rice, oats, peanuts, & Wheat, corn, sorghum, barley, rice, oats, peanuts, & sunflower sunflower [not effective against weevils][not effective against weevils]

Exempt from a residue toleranceExempt from a residue tolerance

Diatomaceous earth (500-1000 ppm)-all seedsDiatomaceous earth (500-1000 ppm)-all seedsExempt from a residue toleranceExempt from a residue toleranceCan be used on organic grainsCan be used on organic grains

Storcide II (3 ppm chlorpyrifos-methyl+0.5 ppm Storcide II (3 ppm chlorpyrifos-methyl+0.5 ppm deltamethrin) deltamethrin) Wheat, barley, oats, rice & sorghumWheat, barley, oats, rice & sorghum

Thiamethoxam (Cruiser and Cruiser Extreme)Thiamethoxam (Cruiser and Cruiser Extreme)

Perma GuardPerma Guard

DryacideDryacide

Diatomaceous earth dustsDiatomaceous earth dusts

Seed protectantsSeed protectants

Should be applied to uninfested seedShould be applied to uninfested seedPrevents insect infestationPrevents insect infestationProvides long-term protectionProvides long-term protection

Treat the entire seed lot intended for storageTreat the entire seed lot intended for storageExpect a 25-30% loss during applicationExpect a 25-30% loss during applicationDo not apply a protectant if storage time is Do not apply a protectant if storage time is

less than a monthless than a monthDo not treat seed that is already infestedDo not treat seed that is already infestedInfested seeds should be first fumigated and Infested seeds should be first fumigated and

then treated with a protectantthen treated with a protectant

A New Seed Protectant-SpinosadA New Seed Protectant-Spinosad

SpinosadSpinosad

Spinosad is produced by Saccharopolyspora spinosa, an aerobic, non-antibiotic actinomycete

Lepidoptera Noctuidae ++++ Diptera Agromyzidae ++++Tortricidae +++ Homoptera Cicadellidae ++Pyralidae +++ Delphacidae ++Plutellidae ++++ Aleyrodidae ++Gelechiidae ++++ Aphididae +Pieridae +++ Orthoptera Blattellidae ++Gracillariidae +++ Blattidae ++

Coleoptera Chrysomelidae +++ Acarina Tetranychidae ++

Thysanoptera Thripidae ++++ Tylenchida Heteroderidae –

Activity spectrum of spinosadActivity spectrum of spinosad

OO

OO

O

O

O

OO

ON

HH

H

H H

Spinosyn A

OO

OO

O

O

O

OO

ON

HH

H

H H

Spinosyn D

Spinosad

What is spinosad?What is spinosad? Fermentation product of the bacterium Fermentation product of the bacterium

Saccharopolyspora spinosaSaccharopolyspora spinosa Broad spectrum insecticide, mixture of spinosyns A Broad spectrum insecticide, mixture of spinosyns A

and Dand D Low mammalian toxicity (rat oral and dermal LDLow mammalian toxicity (rat oral and dermal LD5050, ,

> 5000 mg/kg)> 5000 mg/kg) Unique mode of actionUnique mode of action Stomach toxicity>contact toxicity (5:1)Stomach toxicity>contact toxicity (5:1) Currently labeled for use on over 250+ crops in the Currently labeled for use on over 250+ crops in the

US and registered in over 52 countriesUS and registered in over 52 countries Approved by EPA in January 2005 for treating corn, Approved by EPA in January 2005 for treating corn,

barley, sorghum, millets, oats, rice, triticale, wheat, barley, sorghum, millets, oats, rice, triticale, wheat, birdseed, flower seeds, ornamental seeds, and grass birdseed, flower seeds, ornamental seeds, and grass seeds (Fed Reg 70: 1349-1357)seeds (Fed Reg 70: 1349-1357)

Species susceptible to spinosad Species susceptible to spinosad at 1 mg/kg (ppm)at 1 mg/kg (ppm) Lesser grain borerLesser grain borer

Rice weevilRice weevil Maize weevilMaize weevil

Red flour beetleRed flour beetle Confused flour beetleConfused flour beetle

Sawtoothed grain beetleSawtoothed grain beetle Rusty grain beetleRusty grain beetle Flat grain beetleFlat grain beetle Indianmeal mothIndianmeal moth

Almond mothAlmond moth Angoumois grain mothAngoumois grain moth

Rice moth-resistant to pirimiphos-methylRice moth-resistant to pirimiphos-methyl PsocidsPsocids

Lesser grain borerLesser grain borer

Hard white wheat: Adult survival of and kernel Hard white wheat: Adult survival of and kernel damage caused by lesser grain borers damage caused by lesser grain borers

RateRate

mg/kgmg/kgNo. live adultsNo. live adults No. kernels damagedNo. kernels damaged

7 d7 d 14 d14 d 7 d7 d 14 d14 d

00 24.7 ± 0.3 24.7 ± 0.3 aa

23.3 ± 1.7 23.3 ± 1.7 a a

0.7 ± 0.3 a0.7 ± 0.3 a 1.3 ± 0.9 a1.3 ± 0.9 a

0.10.1 0.0 ± 0.0 b0.0 ± 0.0 b 0.0 ± 0.0 b0.0 ± 0.0 b 0.0 ± 0.0 a0.0 ± 0.0 a 0.0 ± 0.0 a0.0 ± 0.0 a

0.50.5 0.0 ± 0.0 b0.0 ± 0.0 b 0.0 ± 0.0 b0.0 ± 0.0 b 0.7 ± 0.3 a0.7 ± 0.3 a 0.3 ± 0.3 a0.3 ± 0.3 a

1.01.0 0.0 ± 0.0 b0.0 ± 0.0 b 0.0 ± 0.0 b0.0 ± 0.0 b 0.0 ± 0.0 a0.0 ± 0.0 a 0.3 ± 0.3 a0.3 ± 0.3 a

Means within a vertical column followed by different letters are significantly different (P<0.05; Fisher’s protected LSD test)

0.35

0.40

0.45

0.50

Actu

al sp

ino

sa

d r

esid

ue

(m

g/k

g)

0.80

1.00

1.20

1.40

1.40

1.90

2.40

2.90

3.40

Storage time (months)

0 2 4 6 8 10 12

0.06

0.08

0.10

0.12

2.80

3.30

3.80

4.30

y = 4.17 - 0.09x; n = 7; r2 = 0.466; Ho: b = 0; P = 0.09

y = 2.31 - 0.05x; n = 7; r2 = 0.247; Ho: b = 0; P = 0.26

y = 0.83 - 0.003x; n = 7; r2 = 0.005 Ho: b = 0; P = 0.88

y = 0.43 - 0.01x; n = 7; r2 = 0.287; Ho: b = 0; P = 0.215

y = 0.11 - 0.002x; n = 7; r2 = 0.330; Ho: b = 0; P = 0.18

6.0 mg/kg

3.0 mg/kg

1.0 mg/kg

0.5 mg/kg

0.1 mg/kg

Spinosad residues do not show Spinosad residues do not show any significant degradation at 0.1 any significant degradation at 0.1 – 6.0 mg/kg in farm-stored wheat – 6.0 mg/kg in farm-stored wheat during one year of storageduring one year of storage

Bioassays: lesser grain borer mortality after 14 dBioassays: lesser grain borer mortality after 14 d

Storage time (months)0 2 4 6 8 10 12

Mea

n m

orta

lity

(%)

0

20

40

60

80

100

Spinosad-treated wheat(0.1-6.0 mg/kg)

Untreated wheat

Consistent performance of spinosad residues Consistent performance of spinosad residues against lesser grain borer adultsagainst lesser grain borer adults

Performance of spinosad on wheat Performance of spinosad on wheat stored in farm bins: 6-month studystored in farm bins: 6-month study

Trial I (12 bins total)Trial I (12 bins total)3 Kansas farms3 Kansas farms4 treatments4 treatments

Untreated grainUntreated grainSpinosad, 1 ppmSpinosad, 1 ppmChlorpyrifos-methyl, 3 ppmChlorpyrifos-methyl, 3 ppmSpinosad (1 ppm) + Chlorpyrifos-methyl (3 ppm)Spinosad (1 ppm) + Chlorpyrifos-methyl (3 ppm)

Trial II (6 bins total)Trial II (6 bins total)USDA site, Manhattan, KSUSDA site, Manhattan, KS3 treatments3 treatments

Untreated grainUntreated grainAerated grainAerated grainSpinosad, 1 ppmSpinosad, 1 ppm

2002-2003 Trials on 3 Kansas Farms

Farm trials: July 2002 – Jan 2003Farm trials: July 2002 – Jan 2003 Spinosad residues (mg/kg)Spinosad residues (mg/kg)

______________________________________________________________________________________________

Time (months)Time (months) Treatment (Treatment (nn = 3) = 3)

________________________________________________________________

Spinosad Spinosad + Chlorpyrifos-Spinosad Spinosad + Chlorpyrifos-methylmethyl

______________________________________________________________________________________________

00 0.730.73 0.680.68

33 0.620.62 0.450.45

66 0.620.62 0.420.42

FF2,62,6 = 1.71; = 1.71; PP = 0.26 = 0.26 FF2,62,6 = 2.24; = 2.24; PP = 0.19 = 0.19

Grain samplingGrain sampling

Samples removed by probing the top 1 Samples removed by probing the top 1 meter of grain with a trier (7.5 kg/bin)meter of grain with a trier (7.5 kg/bin)

Grain sifted over an inclined sieve twice to Grain sifted over an inclined sieve twice to recover insectsrecover insects

Live insects were counted and expressed Live insects were counted and expressed on a per kg basison a per kg basis

Farm trials: July 2002 - Jan 2003

Time (months)

0 1 2 3 4 5 6

Mea

n n

o. l

ive

inse

cts/

kg o

f w

hea

t

0

5

10

15

20

25Spinosad + Chlorpyrifos-methylControlChlorpyrifos-methylSpinosad

Live insects include adults of the lesser grain borer, Live insects include adults of the lesser grain borer, rusty grain beetle, red flour beetle, and sawtoothed rusty grain beetle, red flour beetle, and sawtoothed grain beetlegrain beetle

14-d Mortality of Lesser Grain Borer Adults

Time (months)

0 1 2 3 4 5 6

Mor

talit

y (%

)

0

20

40

60

80

100

Spinosad + Chlorpyrifos-methylControlChlorpyrifos-methylSpinosad

Lesser grain borer adult progeny after 8 wk

Time (months)

0 1 2 3 4 5 6

Mea

n n

o.

adu

lt p

rog

eny/

250

g

0

200

400

600

800

1000

1200

1400

1600Spinosad+ Chlorpyrifos-methylControlChlorpyrifos-methylSpinosad

14-d Mortality of Red Flour Beetle Adults

Time (months)

0 1 2 3 4 5 6

Mor

talit

y (%

)

0

20

40

60

80

100

Spinosad + Chlorpyrifos-methylControlChlorpyrifos-methylSpinosad

Red flour beetle adult progeny after 8 wk

Time (months)

0 1 2 3 4 5 6

Mea

n n

o. a

du

lt p

rog

eny/

250

g

0

100

200

300

400

500

600Spinosad + Chlorpyrifos-methylControlChlorpyrifos-methylSpinosad

Mean Mean ++ SE insect-damaged kernels SE insect-damaged kernels (IDK)/100 g among treatments(IDK)/100 g among treatments

MonthMonth Spinosad + Spinosad + C-methylC-methyl

SpinosadSpinosad C-C-methylmethyl

ControlControl

00 0 0 0 0 0 0 00

33 0.7 0.7 ++ 0.3 0.3 0.7 0.7 ++ 0.3 0.3 2.0 2.0 ++ 2.02.0

5.4 5.4 ++ 3.53.5

66 1.0 1.0 ++ 0.6 0.6 0.7 0.7 ++ 0.3 0.3 8.3 8.3 ++ 6.06.0

8.3 8.3 ++ 3.53.5

Comparison of Spinosad and Comparison of Spinosad and Aeration Aeration

Flinn, P. W., Bh. Subramanyam, & F. Arthur. 2004. Comparison of Flinn, P. W., Bh. Subramanyam, & F. Arthur. 2004. Comparison of aeration and spinosad for insect suppression in stored wheat.aeration and spinosad for insect suppression in stored wheat.Journal of Economic Entomology 97: 1465-1473.Journal of Economic Entomology 97: 1465-1473.

July 9-10 2003 6 grain bins, filled with 1,100 bu of new-

crop wheat. Treatments: 2 control bins, 2 aerated bins,

and 2 bins with Spinosad-treated wheat.

400 red flour beetles400 rusty grain beetles400 lesser grain borers

Insects added monthlybetween Jul and Oct, 02

Lesser Grain Borer

Jul 16 Aug 12 Sep 10 Oct 08 Nov 05 Dec 03 Jan 08

Ins

ects

/Kg

0

20

40

60

80

100

Control Aerated Spinosad

Rusty Grain Beetle

Jul 16 Aug 12 Sep 10 Oct 08 Nov 05 Dec 03 Jan 08

Inse

cts/

Kg

0

20

40

60

80

100

Control Aerated Spinosad

Red Flour Beetle

Jul 16 Aug 12 Sep 10 Oct 08 Nov 05 Dec 03 Jan 08

Inse

cts/

Kg

0

20

40

60

80

100 Control Aerated Spinosad

Jul Aug Sep Oct Nov Dec Jan Feb

Ave

rag

e G

rain

Tem

per

atu

re (

oC

)

5

10

15

20

25

30

35

40

Control Control Spinosad Spinosad Aerated Aerated

USDA farm bin trials: Insect damaged USDA farm bin trials: Insect damaged kernels among treatmentskernels among treatments

MonthMonth UntreatedUntreated AeratedAerated SpinosadSpinosad

00 00 00 00

11 00 00 1.51.5

22 55 0.50.5 11

33 1212 0.50.5 2.52.5

44 16.516.5 0.50.5 22

55 3030 1.51.5 0.50.5

66 70.570.5 66 1.51.5

IDK (FDA Defect Action Level) = 32 IDK/100 gIDK (FDA Defect Action Level) = 32 IDK/100 g

Registration statusRegistration statusEPA approval in January 2005EPA approval in January 2005CODEX approval in June 2005CODEX approval in June 2005Commercial products-2007Commercial products-2007Bayer CropScience (Gustafson) Bayer CropScience (Gustafson)

Contain (liquid and dry)Contain (liquid and dry)AgrilianceAgriliance

Execute (pirimiphos-methyl, 4 ppm + Execute (pirimiphos-methyl, 4 ppm + spinosad, 1 ppm)spinosad, 1 ppm)

Organic and non-organic usesOrganic and non-organic uses

ConclusionsConclusions

Spinosad has broad spectrum of Spinosad has broad spectrum of activity at 1 ppm against a range of activity at 1 ppm against a range of speciesspecies

It is a reduced-risk insecticideIt is a reduced-risk insecticideIt is stable on seeds-6 months to 2 It is stable on seeds-6 months to 2

years)years)Can be combined with other Can be combined with other

protectants protectants

Infrared Technology On the energy spectrum, infrared radiation lies between visible and On the energy spectrum, infrared radiation lies between visible and

microwave radiationmicrowave radiation

Electromagnetic energy with wavelengths 0.078 to 1000 Electromagnetic energy with wavelengths 0.078 to 1000

μμm long can be transferred to any material that can m long can be transferred to any material that can

absorb it, resulting in that material’s increased temperatureabsorb it, resulting in that material’s increased temperature

Water absorbs infrared energy at 3, 4.5, and 6 Water absorbs infrared energy at 3, 4.5, and 6 μμmm

Dimensions: length 6.1 m (20 ft); width, 61 cm (24 inches)Dimensions: length 6.1 m (20 ft); width, 61 cm (24 inches)

Heater dimensions: 5.5 m long and 25.4 cm wide. There Heater dimensions: 5.5 m long and 25.4 cm wide. There are a total of 4 pairs of heaters above the conveyerare a total of 4 pairs of heaters above the conveyer

Distance between heater surface and conveyer surface: Distance between heater surface and conveyer surface: 4.4 cm (lowest point), 8.9 cm (highest point)4.4 cm (lowest point), 8.9 cm (highest point)

7,200 BTU/sq ft; 216,000 BTU/h7,200 BTU/sq ft; 216,000 BTU/h

Grain flow rate: 1,308 kg/h (2,880 lb/h) [65 kg/3 min]Grain flow rate: 1,308 kg/h (2,880 lb/h) [65 kg/3 min]

Natural gas pressure: 9 cm water column (28 cm water Natural gas pressure: 9 cm water column (28 cm water column = 0.4 psi)column = 0.4 psi)

Grain treated in a single layer (0.3 mm thick)Grain treated in a single layer (0.3 mm thick)

Residence time of grain in the heating zone: 43 secResidence time of grain in the heating zone: 43 sec

Commercial Heater Specifications

Commercial Tests

Mortality of Adult Insects: Mortality of Adult Insects: Commercial Scale Tests Commercial Scale Tests

SpeciesSpecies Temp Temp range range ((ooC)C)

Total no. Total no. adultsadults

% Mortality% Mortality

Red flour Red flour beetlebeetle

64-8264-82 200200 100.0100.0

57-7157-71 15541554 99.699.6

Rice weevilRice weevil 41-7741-77 200200 100.0100.0

Merchant grain Merchant grain beetlebeetle

40-8240-82 20022002 100.0100.0

Lesser grain Lesser grain borerborer

57-7157-71 20342034 98.998.9

63-7663-76 27072707 100.0100.0

Mortality of Lesser Grain Borer Larvae:Mortality of Lesser Grain Borer Larvae: Commercial Scale Tests Commercial Scale Tests

Commodity

Larval age at treatment (days

since egg introduction)

Emergence in untreated grain (50g)

Emergence in grain exposed to

infrared (50g)

% Reduction in

emergence of adults

Wheat 18-22 17.20 0.00 100.00Wheat 13-17 84.07 1.00 98.81Wheat 7-11 60.27 0.00 100.00Wheat 2-6 42.13 0.10 99.76Rice 8 & 9 18.83 1.18 93.75Rice 7 & 6 16.67 0.21 98.76Rice 4 & 5 5.67 0.24 95.85Rice 3 & 2 2.33 0.03 98.74

Bench Top Model Tests

Bench top model of infrared heater showing the propane bottleand pan with hard red winter wheat. The non-contact infrared thermometer (Raytek®, Model MX4) is used for continuous measurement of temperatures during exposure to infrared via RS-232 cable connected to a laptop computer

Microbial Tests - Molds

Treatment% Wheat moisture

(wet basis)

Mold infected kernels (%),

not disinfected

with chlorox

Mold infected

kernels (%), chlorx

disinfected

Mold count (cfu/g)

Control 12.7 + 0.01 100 95.7 + 2.3 14767 + 9418Infrared-Treated 12.1 + 0.07 100 70.7 + 5.2 197 + 41

Effect of infrared on naturally-occurring molds in wheat. 113.5 g of wheat was exposed for 60 seconds, 12.7 cm from the heater. Temperature range: 32-83°C.

Microbial Tests - Escherichia coli O157:H7

Effect of infrared on E. coli O157:H7. 113.5 g of wheat was exposed for 60 seconds, 12.7 cm from the heater. Temperature range: 32-83°C.

TreatmentE. coli (cfu/g)

Control 7.4 x 105

Infrared-Treated 1.3 x 104

Thank youThank you