Download Insects

Insect Pest Management
• Insects
– 1.5 - 30 million species
– Most Insects are not pests
“For 150 million years, insects have served as the
sexual handmaidens to the flowering plants. Most
plants on earth cannot reproduce without them.
When the bugs fly from flower to flower for the
nectar, some of the pollen is transferred from
stigma to stigma. Wham bam, thank you, ma’am.”
-Rowan Jacobsen, Fruitless Fall
Classification
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Kingdom >
Animal
Phylum > Arthropoda (one of 33 Phyla)
Class
> e.g. Insecta, Arachnida
Order
> e.g. Coleoptera, Diptera
Family
Genus
Species
1.5 – 30 million
ARTHROPODS
• Legs with joints
• Segmented Bodies
• Members of that Group
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Insects
Crustaceans
Mites
Ticks
Spiders
Millipedes
Centipedes
Symphylans
CLASS INSECTA (HEXAPODA)
• Adults have 6 legs
• 3 body segments,
– Head, thorax and abdomen
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One pair of antennae
Some have wings
Spineless = invertebrate
Exoskeleton
MOST IMPORTANT
FEATURES OF INSECT
PESTS
• MOUTHPARTS:
– Piercing/sucking
– Chewing
– Sponging
– Siphoning
arthursclipart.org
Mouthparts: Chewing
Beetles (Coleoptera)
Caterpillars (Lepidoptera)
Grasshoppers (Orthoptera)
Termites (Isoptera)
Mouthparts: Rasping –Sucking (e.g
Thrips)
Piercing- Sucking (e.g. Mosquito)
Sponging Mouthparts
(e.g. Housefly)
Siphoning
Chewing – Lapping (e.g. Honey Bee)
METAMORPHOSIS
• INSECTS CHANGE FORM AS THEY
DEVELOP
• FOUR TYPES OF METAMORPHOSIS
– None
– Complete
– Incomplete
– Gradual
No Metamorphosis
Egg
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Juvenile
Adult
Body size & proportions change
Some times segments may be added;
No wings
Same habitat
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Complete Metamorphosis
Egg
Larvae
Pupa
Adult
• Immatures rarely resemble adults
• Wing development begins internally
• Different habitats
Southwest Corn Borer
Incomplete Metamorphosis
Egg
Naiads
Adult
• Immatures may or may not resemble
adults
• Immatures in water
• No pupal stage
• Different habitats
Gradual metamorphosis
Egg
Nymphs
• Similar in appearance
• Wing pads in later immature
stages
• Same habitats
Adult
Gradual metamorphosis similar to simple, except most of these
insects will develop wings.
OTHER ARTHROPODS
• ARACHNIDS
– Spiders, mites, ticks
SPIDERS
• USUALLY
CONSIDERED
BENEFICIAL
• Few poisonous
• Eat other insects
(beneficials, too)
• GENERAL
FEEDERS
MITES
• FOLIAGE FEEDERS
– Spider mites, spruce mites
• BUD FEEDERS
– Cyclamen mites, Eriophyoid mites – only
mites known to transmit viruses (gall
mites)
• BULB MITES
• PREDATOR MITES
Eriophyid
mites
Predator mites
Many mites are predator mites – feed on
pest mites. Commercially available and good
biological control agents!
CRUSTACEANS
• Sow bugs, pill bugs
– Same class as crabs, lobster
CENTIPEDES
• Predators that feed on insects and spiders
• One pair of legs per segment
• 15 or more pairs of legs
MILLIPEDES
• FEED ON DECAYING PLANT
MATTER AND SOMETIMES PLANT
ROOTS
• 2 PAIRS OF LEGS PER SEGMENT
• 30 OR MORE PAIRS OF LEGS
SYMPHYLANS
• SOIL DWELLING PESTS
• FEED ON GERMINATING
SEEDS, ROOTS AND BULBS
• WHITE WITH NUMEROUS
LEGS AND PROMINENT
ANTENNAE
• Adults = 12 pairs of legs
• Biology and Control:
• http://insects.ippc.orst.edu/
pnw/insects?30IPMW02.dat
BENEFICIAL ARTHROPODS
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Products – Silk, dyes
Food source
Improved soil structure
Scavengers
Predators and parasites of other
pests
BENEFICIALS
• PREDATORS
– Directly catch and
feed on prey
• PARASITES
– Use other insects to
incubate eggs and
feed larvae
INSECT PESTS
• INSECTS CAUSE DAMAGE TO PLANTS IN
MANY WAYS
– Fruit and seed destruction
– Tissue damage and vigor reduction
– Disease transmission
– Aesthetics
– Public nuisance (honeydew)
How to tell if you have a pest
• SYMPTOMS
– What the host shows or exhibits
• Tissue damage
• Root damage
• Distortion
• Discoloration
• Dieback
Boll weevil,
kidsbrittanica.com
How to tell if you have a pest
• SIGNS - What the pest leaves for
you to find
• Frass: debris the insect leaves,
shed skin from molting, feces,
webbing
• Pest or eggs, froth, honeydew,
sawdust
Amateur Entomologists’
Society amentsoc.org
Grubs
Grubs (Order: Coleoptera)
• Weevil larva
• Larva feed on roots
– Adults also feed on foliage and seed
• Adult mouthparts are curved into a
downward curving snout
– Characteristic semi-circular notching on
the leaves
• Serious pests of ornamental plants
Grubs
Other Root Feeders
• Crane fly larva - Order: Diptera
• Wireworms - Order: Coleoptera
• Fungus gnat larva - Order: Diptera
Fungus Gnat
Wood Borers (Order: Coleoptera)
• Larva have well developed chewing
mouthparts and can reach great size
• Larva bore into woody trunks and
twigs
– Branches can be girdled and dieback
• Eggs laid in wounds of woody plants
Wood Borers
Leaf Miners
• Can be moth, beetle or fly larva
• Orders: Lepidoptera, Coleoptera,
Diptera
• Cause damage on ornamental
evergreens
• Damage to edible leafy crops and
flowers
Vegetable Leaf Miner
Birch Leaf Miner
Bark Beetles (Order:
Coleoptera)
• Cause leaf damage, tunnel under
bark
• Serious vectors of fungal diseases
– Example: Dutch Elm Disease
Bark Beetle
Bark Beetle
Sucking Insects (Order: Homoptera)
• Example: Aphids, Leafhoppers and
Scale
• Piercing-sucking mouthparts
• Feeding damage, causing distortion
and weakening plants
• Can spread plant viruses
Aphids
Aphids
Aphids
Rasping-sucking pests (Order: Thrysanoptera)
• Thrips
– Directly damage plants by cuticle
destruction and feeding damage
– Vectors of plant viruses
Rasping-sucking pests (Order: Acarina)
• Spider mites
– Feeding damage
– Eriophyid mites, vector diseases
(viruses)
Gall forming insects
• Spruce Adelgids
– Homoptera
• Honey locust pod gall midge
– Diptera
• Bladder gall mites on Maple
– Acarina
• Oak leaf galls, wasp
– Hymenoptera
Gall forming insects
Gall forming insects
Tent Caterpillars - Order: Lepidoptera
• Leaf skeletonizers
• Leaf rollers
Caterpillars
Twig Girdlers (Order:
Coleoptera)
• Borers, weevils,
– Cause dieback of twigs, shoots
Leaf damaging insects
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Many orders, adults and larva
Chewing, reduce foliage
Sucking and rasping damage
Reduce plant vigor
Ruin aesthetics
Can lead to disease infections
• Entomology for Master Gardeners
• http://pest.ca.uky.edu/EXT/master_g
ardener/entbasics/mouthparts/mout
hparts.shtml