Entomology

Original PowerPoint by

Mark Morgan

Modified by Georgia Agriculture Education

Curriculum Office

November 2005

What is Entomology?

- the branch of zoology that deals with the study of insects

• On average there are more than 750,000 species of insects that have been identified worldwide.

• There are only approximately 10,000 species of insects that are harmful to humans.

Problems

– Deadly epidemics of the past have been caused by diseased organisms carried by insects.

– Example: Bubonic Plague epidemic that wiped out the population of Europe in the 14 century was carried by fleas that infested rodents

Classification of insects:

–Kingdom–Phyla–Class–Order–Family–Genus–Species

• The highest level is the Kingdom

• The most specific is the species level.

• Organisms are usually classified by the genus and species.

• This is called a binomial nomenclature.

Six orders of insects:

- Orthoptera- which includes the grasshopper and locust

– Hemiptera- which includes the true bugs such as leaf hoppers and plant bugs

– Lepidoptera – moths and butterflies

– Homoptera- aphids

Cont’d…

– Thysanoptera- thrips– Coleoptera- which is

the largest group of the insect orders this has beetles

How are insects grouped?

• by the way they feed on plants

• by their mouth parts

Six Mouth Parts

– Sponging– Rasping- sucking– Siphoning– Chewing-lapping– Chewing– Piercing- sucking

• Insects have no internal skeleton and they rely on their hard outer coating, exoskeleton, which protects their inner organs and supports their body.

Parts of an Insect

– Head– Thorax– Abdomen

Head

– Has a pair of compound eye and two sensory appendages called antennae

Thorax

– is divided into three segments from which are attached three pairs of legs

Abdomen

– is attached to the thorax

– which will contain more segments

Life Cycles

– Incomplete Metamorphosis

– Complete Metamorphosis

Incomplete Metamorphosis

• Eggs

• to Early nymph (no wings)

• to late nymph (wings developing)

• Goes to Adult

Complete Metamorphosis

• Eggs to

• Larva to

• Pupa to

• Adult

What Is a Larva?

• It is when the young insect has soft tubular body and looks very much like a worm

What Is the Pupa Stage?

• The larva matures and will pass through the pupa stages which is usually a relatively dormant stage.

What is DDT?

– This is a chemical that was discovered by German name Othmar Zeidler in 1874.

– It is a chemical used to reduce the number of insects in a given area.

– Example: mosquitoes in the tropics

Integrated Pest Management

• Cultural methods• Insect diseases and

predators• Pheromones• Release of sterile

males• Insect resistant plants

varieties