1. Plant and Soil Science Plant pathogens and Pest Management Topic: Entomology/ insect Biology (2042)
Brian Sobecki

2. Insect Facts Study of insects is called “Entomology’
Insects have lived on earth for 250 million years.
There are an estimated 1,000,000 species of insect on our planet.
Insects can be helpful, neutral, or harmful to humans

3. Biology of Insects
The body of an insect is divided into three parts the Head, Thorax, and Abdomen.
The word insect come from the Latin word ”insectum” which means “cut into”.
The segmented body gives them the advantage of movement and activity.

4. Biology of Insects
Segmentation also provides efficiency. Each body segment is specialized into functions such as:
Securing food
Locomotion
Reproduction

5. The Insect Body The Head (contains antennae and Mouth parts)
Eyes are either simple or Compound.
Antennae are used for smelling and feeling.
Mouth parts are for either sucking or chewing.
Mouth parts are the most variable of all insect characteristics.
They are often used to determine the type of control measures that will be most effective for a particular insects.

6. The Insect Body The Thorax (Locomotion Segment)
Contains the wings and legs.
An insect may have zero, one or two pairs of wings.
The thorax also has three pairs of legs.

7. The Insect Body
The Abdomen ( contains digestive, reproductive, respiratory and excretory organs)
Shrinks or swells according to the state of those organs.
Variations occurs when the insects eat, produces eggs or fills with excrement.

8. Life Cycles
The several changes that insects go through to reach maturity is called Metamorphosis.
There are four variations or Metamorphosis
A few insects have no metamorphosis.
Insects emerge from eggs looking exactly like adults, except smaller
Example: Silverfish

9. Life Cycles Some insects go through Gradual metamorphosis.
They change shape gradually.
Example: Grasshopper and Cricket

11. Life Cycles Other Insects have an incomplete metamorphosis.
Change gradually until they reach the last stage.
They change quickly into their last stage after their last molt. ( shedding of the outer layer of skin)
Example: Dragonfly

12. Life Cycles Some have a complete metamorphosis.
Insects go through Four stages: Egg, Larvae, Pupa, and Adult
None of the young stages look anything like the adult stage.
Example: Moths and Butterflies

14. Life Cycles
Understanding metamorphosis will help you better understand techniques of insect control.
Egg and pupa stages are most resistant to chemical spray.
The larval stage are the most destructive, but most vulnerable to spray.
The adult stage is also destructive, but controllable.

15. Pictures
(All butterflies pictures) The Butterfly Guide,
Aeshnidea; Digital Dragonflies,
Insect Biology and Ecology: a primer; Biological control: A guide to natural enemies in North America; Weeden, Shelton, and Hoffmann;