Detection and Monitoring of Stored-Grain Insects Bh. Subramanyam, Carl Reed, and Phil Sloderbeck* Department of Grain Science and Industry *Department.

Detection and Monitoring of Detection and Monitoring of Stored-Grain InsectsStored-Grain Insects

Bh. Subramanyam, Carl Reed, and Phil Bh. Subramanyam, Carl Reed, and Phil Sloderbeck*Sloderbeck*

Department of Grain Science and IndustryDepartment of Grain Science and Industry*Department of Entomology*Department of Entomology

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

[email protected]@ksu.edu2006 Grain Handlers Workshop2006 Grain Handlers Workshop

DetectionDetection

Looking for presence or absence of Looking for presence or absence of an insect or an infestation (with an insect or an infestation (with respect to your sampling device)respect to your sampling device)

The type of device used and the The type of device used and the number of samples taken determine number of samples taken determine how good you are in finding an insect how good you are in finding an insect or an infestationor an infestation

MonitoringMonitoring

Tracking trends in insect numbers or Tracking trends in insect numbers or infestation levels over timeinfestation levels over time

Helps you know when to take actionHelps you know when to take actionHelps you understand how Helps you understand how

populations are behaving with populations are behaving with respect to environmental conditionsrespect to environmental conditions

Helps you assess effectiveness of Helps you assess effectiveness of pest management actionspest management actions

Detection and Monitoring Detection and Monitoring Require SamplingRequire Sampling

Counting all insects in a bin is difficultCounting all insects in a bin is difficultTheir distribution is unknownTheir distribution is unknownIt may take forever to count all It may take forever to count all

insects presentinsects presentTime and money are limited Time and money are limited Sampling will help in making inferences Sampling will help in making inferences

about the insects inhabiting a bin or siloabout the insects inhabiting a bin or silo

Infestation in RailcarsInfestation in Railcars

WheatWheat21, 3 kg wheat samples/railcar were taken from 8 21, 3 kg wheat samples/railcar were taken from 8

railcars (Perez-Mendoza et al., 2004) railcars (Perez-Mendoza et al., 2004) They also had a lot of IDK They also had a lot of IDK 1024 insects were found in 7 of 8 railcars1024 insects were found in 7 of 8 railcars3% of insects were found immediately after 3% of insects were found immediately after

sample collectionsample collection77.1% were found 7 weeks after sample 77.1% were found 7 weeks after sample

incubationincubation

Relevance to detection??Relevance to detection??Relevance to fumigant efficacy??Relevance to fumigant efficacy??

In Concrete ElevatorsIn Concrete Elevators

High insect density is within the top 3-4 ft and all High insect density is within the top 3-4 ft and all of the insects can be found within 40 ft from the of the insects can be found within 40 ft from the toptop

Discharge from spouts onto reclaim belt had Discharge from spouts onto reclaim belt had more insects than grain samples taken with a more insects than grain samples taken with a vacuum probevacuum probe

Fewer insects were found in treated empty bins Fewer insects were found in treated empty bins and the treatment effectiveness lasted 12 weeksand the treatment effectiveness lasted 12 weeks

Relevance: Understand where to sample!Relevance: Understand where to sample!

Grain Sampling Methods: Grain Sampling Methods: Absolute EstimatesAbsolute Estimates

Diverter-type Diverter-type samplersampler

PelicanPelican Ellis cupEllis cup Grain trierGrain trier Vacuum probeVacuum probe ScoopScoop

DiverterDiverter

Pelican SamplerPelican Sampler

Ellis CupEllis Cup

Grain BulkGrain Bulk

• Probe sampler• Spear or trier

Vacuum probe forVacuum probe forbulk-stored grainbulk-stored grain

InsectomatInsectomat

Capable of processing Capable of processing large sampleslarge samples

Pass grain sample Pass grain sample twice for extraction of twice for extraction of all insects present all insects present (need to check (need to check efficiency in efficiency in separating insects separating insects from grain)from grain)

Bagged GrainBagged Grain

Torpedo (spear) samplerTorpedo (spear) sampler Coning and quarteringConing and quartering Boerner divider and other Boerner divider and other

dividers (sample dividers (sample reduction)reduction)

Sieving (check efficiency)Sieving (check efficiency)

Torpedo SamplersTorpedo Samplers

Sieve SamplersSieve Samplers InclinedInclinedsievesieve

DividersDividers

Absolute Estimates Are…Absolute Estimates Are…

More reliable estimatesMore reliable estimates Pest management decision should be Pest management decision should be

based on absolute estimatesbased on absolute estimates Threshold for management: 1 insect/kgThreshold for management: 1 insect/kg Time consuming, laborious, and expensive Time consuming, laborious, and expensive

Insect Sampling Devices: Insect Sampling Devices: Relative EstimatesRelative Estimates

Number of insects found in a trap Number of insects found in a trap constitutes a relative estimateconstitutes a relative estimate

There are many trap typesThere are many trap types

Sticky traps for Sticky traps for flying insectsflying insects

For almond moths andFor almond moths andIndianmeal mothsIndianmeal moths

Pherocon II trapsPherocon II traps

Pheromone lure

Traps for Crawling InsectsTraps for Crawling Insects

Provides a hiding placeProvides a hiding place Includes various designsIncludes various designsCan be used with pheromone lures or food Can be used with pheromone lures or food

baits to enhance capture of speciesbaits to enhance capture of speciesCan capture multiple speciesCan capture multiple species

Corrugated Harborage TrapsCorrugated Harborage Traps

Corrugated Corrugated Paper TrapsPaper Traps

Bait-Bag Bait-Bag TrapsTraps

Netlon netting (8x16 cm)Netlon netting (8x16 cm)Aperture 2 mmAperture 2 mmBrown rice-60 gramBrown rice-60 gram

Food-baited TrapsFood-baited Traps

Traps for Use in Bulk-Stored GrainTraps for Use in Bulk-Stored Grain

Perforated metal or plastic probes or cones Perforated metal or plastic probes or cones inserted into grain bulksinserted into grain bulks

Insects crawl through the holes and fall into Insects crawl through the holes and fall into a collection tube or conea collection tube or cone

Pitfall Cone TrapPitfall Cone Trap

95 mm x 125 95 mm x 125 mm cone-mm cone-shaped with shaped with holesholes

Very sensitiveVery sensitive For surface For surface

area of the area of the grain bulkgrain bulk

Probe trapsProbe traps

370 mm x 27 mmFunnel and collecting tubeCan be inserted into the grain bulk

Trap Retrieval is Critical! Trap Retrieval is Critical!

Automated counts of insects in grainAutomated counts of insects in grain(OPIsystems.com)(OPIsystems.com)

Stormax InsectorStormax Insector

(a)

(b)

(c)

(d)

51.3

cm

0

50

100

150

0 10 20 30 40 50 60 70 80 90 100 110 120

Composite Adjusted Target Peak Amplitude

Nu

mb

ers

of

Ins

ects

Flat grain beetle (n=2105)

Rusty grain beetle (n=1284)

Sawtoothed grain beetle (n=1620)

Lesser grain beetle (n=1387)

Red flour beetle (n=2432)

Rice weevil (n=1834)

OPI Systems, Calgary, CanadaOPI Systems, Calgary, Canada

Relative Estimates Are…..Relative Estimates Are…..

Faster, cheaper, and easier than absolute Faster, cheaper, and easier than absolute methodsmethods

Traps work 24 hours a day, 7 days a weekTraps work 24 hours a day, 7 days a week Interpretation of numbers is difficult (biological Interpretation of numbers is difficult (biological

and environmental variable affect insect and environmental variable affect insect captures)captures)

Can be used to pin point problem areasCan be used to pin point problem areas Can be used to evaluate effectiveness of pest Can be used to evaluate effectiveness of pest

management measuresmanagement measures

Take Home PointsTake Home Points

Be a truck, railcar, bin, or elevator siloBe a truck, railcar, bin, or elevator silo Take more samples than fewer samplesTake more samples than fewer samples More than 10 and less than 30More than 10 and less than 30 Information from sampling can be used in 2 Information from sampling can be used in 2

computer programs (SGA and SGA Pro) to make computer programs (SGA and SGA Pro) to make pest management decisionspest management decisions

Without proper detection and monitoring of Without proper detection and monitoring of insects you will treating more number of times insects you will treating more number of times than needed or fail to treat when you really need than needed or fail to treat when you really need to!to!