Download Pests and Diseases

Pest Management
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.
–
–
–
–
–
Chewing
Piercing
Rasping
Siphoning
Sponging
Chewing Insects
• Insects tear, chew or grind food
• Examples
– grasshopper
– beetle
Piercing Insects
• Punctures plant and sucks the sap
Rasping insect
• Rasps or breaks surface and
sucks sap
• Example
– thrips
Siphoning insects
• Have a coiled tube they dip into
liquid food such as nectar and
draw it in
• Example
– butterfly
Sponging Insects
• Have two sponge-like structures
that collect liquid food and move
it into the food canal
• 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
Plant Diseases
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
– disease causing organism or
pathogen must be present
– favorable environment for disease
organism to develop
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
Fungi
• 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.
Examples of Common
Fungi
• Damping off causes young plants
and seedling to rot off at the soil
level.
• Rust cause small spots on the
leaves that resemble yellow,
orange, brown or red rust mainly
on the underside of leaves.
Examples of Common
Fungi
• Powdery mildew grows on the
upper and lower leaf surface as
white or gray powdery substance.
It is a common disease of
houseplants.
• Galls are round swellings or
growths usually on tree branches
or leaves.
Fungi
• Examples caused by bacteria or
fungi are powdery mildew, blights,
canker, rots, wilts and smut,
canker, galls, leaf spot, mildew,
rots and smut.
Viruses
• Viruses are pathogens with an
extremely narrow host range
– Examples of common viruses:
• Tobacco mosaic virus which attacks
tomatoes, peppers, poinsettias and
tobacco.
– Can be transfer from human hands
of a smoker
– Cause leave to have irregular
mottled areas with patterns ranging
from dark to light green and yellow
to white
Viruses
• Examples caused by viruses, bacteria
or fungi are wilts and blights.