Pests & Diseases

Insects - Anatomy Insects

Small animals that have three body regions and three pairs or six legs.

The three body regions are…. Head Thorax Abdomen

Parts of the Insect

Life Cycle of Insects

Complete metamorphosisEggLarva Worm Caterpillar

PupaAdult Flies Beetles

Life Cycle of Insects

Incomplete metamorphosisEggNymphAdult

Chewing Insects

BeetleEat leaves, stems,

flowers, fruit and nuts.

Chewing Insects

CutwormsUsually attack stems,

but may eat other plant parts.

Chewing Insects

Caterpillars Larva of moths and butterflies and are fuzzy or hairy. Eat young leaves and stems. Roll up in leaves making the leaves curl.

Chewing Insects Grasshoppers

Eat all parts of plants.

Sucking Insects

AphidsPierce & suck juices.Known as plant lice.Cause stunted growth

and yellow spotted leaves.

Causes sticky substance and black mold which attracts ants.

Sucking Insects

MealybugsPierce and suck from underside of leaves and in leaf

axils.Causes yellow appearance and sticky secretions.

Sucking Insects

WhitefliesFeed on underside of

young leaves causing yellowing.

They will look like flying little white specks when plants are shaken.

Plant Diseases

What is a Disease??? A plant disorder caused by an infectious pathogen or agent.

Conditions Needed for a Disease Three conditions are necessary for a disease in a plant.

Host plant Disease causing organism or pathogen must be present. Favorable environment for disease organism to develop.

The Disease Triangle

What Causes a Disease?? The groups of pathogens are….

Bacteria Fungi Viruses Parasitic plants

Mistletoe Dodder Lichens

FUNGI

Parasitic Plants

LICHENSMISTLETOE DODDER

Controlling DiseasesWarm temperatures and moist conditions in

greenhouse plant production make most horticulture plant diseases worse because…. Environmental conditions that support disease-causing

pathogens.Preventing plant diseases is better than treating

the diseases.Plant diseases must be identified before they can

be treated.

Plant Diseases – Blight

Cause plants to quickly turn brown as if they had been burned.

Plant Diseases – Canker

Causes open wounds on woody plant stems.

Plant Diseases – Damping Off

A fungal disease that causes young plants and seedlings to rot off at the soil level.

Plant Diseases – Galls Round swellings or growths on plants.

Plant Diseases – Leaf Spots

Rings of different shades of brown, green, or yellow that make spots on leaves.

Plant Diseases – Mildew

Grows on leaf surfaces (both upper & lower) as white, gray or purple spots.

Plant Diseases – 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.

Plant Diseases – Rot

Causes plants to decay & die.

Plant Diseases – Rust

Causes small spots on leaves that resemble yellow, orange, brown or red rust mainly on the underneath side of leaves.

Plant Diseases – Smut

A black powdery disease that causes blisters that burst open releasing black spores.

Plant Diseases – Wilts

Disease that blocks the uptake of water in plants stems causing it to wilt.