Pest Management
Essential Standard 8.00Compare distinguishing
chrematistics of pest.
Objective 8.01
• Discuss the anatomy and life
cycle of pest.
What is an insect?
• Small animals that have three
body regions and three pairs of
legs equaling six legs
• Body regions
– head
– thorax
– abdomen
Types of Insects
• The five types of mouthparts are
important in identifying and
controlling insects.
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–
–
–
–
Chewing
Piercing
Rasping
Siphoning
Sponging
Chewing Insects
• Insects tear, chew or grind food
• Examples
– grasshopper
– beetle
Piercing Insects
• Punctures plant and sucks the sap
usually from the underside of the
leaves or on the stem.
• Includes aphids, whiteflies, and
mealy bugs.
• Damage causes yellow spotted
leaves
Rasping insect
• Rasps or breaks surface and
sucks sap
• Damage plant tissue becomes
speckled and white
• Example
– Thrips
Siphoning insects
• Have a coiled tube they dip into
liquid food such as nectar and
draw it in
• Cause little to no damage
• Example
– Butterfly
Sponging Insects
• Have two sponge-like structures
that collect liquid food and move
it into the food canal
• Can carry germs or diseases
• Example
– housefly
Life Cycles
• Complete metamorphosis has four
stages
–
–
–
–
egg
larva-worms or caterpillars
pupa
adult-flies, beetles, etc.
Life Cycles
• Incomplete metamorphosis has three
stages
– egg
– nymph
– Adult
• Insects must be killed when they are
feeding or actively moving on the plant
Life Cycles
Chewing Insects
• Parts of leaves are eaten away
–
–
–
–
beetles
cutworms
caterpillars
grasshoppers
Chewing Insects
• Beetles
– eat leaves, stems, flowers, fruit and
nuts
• Cutworms
– usually attack stems, but may eat
other plant parts
Chewing Insects
• Caterpillars
–
–
–
–
larva of moths and butterflies
fuzzy or hairy
eat young leaves and stems
roll up in leaves making leaves curl
• Grasshoppers
– eat all parts of plants
Sucking Insects
•
•
•
•
•
•
Aphids
Leaf bugs
Mealy bugs
Scale
Thrips
Whiteflies
Aphids
• Pierce and suck juices
• known as plant lice
• cause stunted growth and yellow
spotted leaves
• causes sticky substances and
black mold
• will attract ants
Aphids
Leaf Bugs
• Cause plants to look unhealthy
• plants will lose their normal color
and wilt
Leaf Bugs
Mealy Bugs
• Pierce and suck from underside
of leaves and in leaf axils causing
yellow appearance and sticky
secretions
Mealy bugs
Scale
• Appear as black or brown raised
lumps attached to stems and
underside of leaves causing yellow
leaves and stunted growth
Scale
Thrips
• Chew and then suck causing plant
tissue to become speckled or
whitened, leaf tip to wither, curl
up, or die
Thrips
Whiteflies
• Feed on underside of young leaves
causing yellowing
• will look like flying little white
specks when plants are shaken
Whiteflies
Mites
• Attack underside of leaves
causing gray to grayish-green
spots
• severe infestations cause
webbing
Mites
Plant Diseases
Objective 8.02
• Discuss diseases and viruses.
Diseases
• A disease is a plant disorder
caused by an infectious pathogen
or agent
Diseases
• There are 3 conditions necessary
for diseases in plants
– host plant – A plant the disease
attacks
– disease causing organism or
pathogen must be present
– favorable environment for disease
organism to develop
Pathogens
• There are four groups of
pathogens
–
–
–
–
bacteria
fungi
viruses
parasitic plants (attach to plants)
• mistletoe
• dodder
• lichens
Bacteria
• Single celled microorganisms
• Examples of common bacteria
diseases:
– Leaf spot
• Rings of different shades of brown,
green or yellow spots on leaves.
– Blight
• cause plant to quickly turn brown or
black as if they had been burned
Blight
Leaf Spots
Fungi
• Cannot make their own food
– They develop hyphae, structures
that grow and absorb nutrients
from the host plant
– Many fungi are spread by spores.
Damping off
• A fungal disease that causes
young plants and seedlings to rot
off at soil level
Damping Off
Rust
• Causes small spots on leaves that
resemble yellow, orange, brown or
red rust mainly on the underneath
side of leaves
Rust
Mildew
• Grows on leaf
surfaces--both
upper and lower-as white, gray or
purple spots
• Common disease
of houseplants
Gall
• Swellings or growths on plants
• Usually on tree branches or
leaves
Viruses
• Viruses are pathogens with an
extremely narrow host range
Mosaic
• Caused by viruses that make the
leaves have irregular mottled
areas with patterns ranging from
dark green to light green to
yellow to white
• Can be transferred from human
hands of a smoker. Be sure to
wash hands!
Mosaic
Others Diseases
Canker
• Causes open wounds on woody
plants
Canker
Rots
• Cause plant to decay and die
Smut
• A black, powdery disease that
causes blisters that burst open
releasing black spores
Smut
Wilt
• A disease that blocks the uptake
of water in plant stems causing
plants to wilt
Wilt