Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Plant and Soil Science Plant pathogens and Pest Management Topic: Entomology/ insect Biology (2042) Brian Sobecki 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 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. Biology of Insects – Segmentation also provides efficiency. Each body segment is specialized into functions such as: • Securing food • Locomotion • Reproduction 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. 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. 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. 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 Life Cycles – Some insects go through Gradual metamorphosis. • They change shape gradually. • Example: Grasshopper and Cricket www.nysaes.cornell.edu/ent/biocontrol/info/primer.html#anatomy Life Cycles – Other Insects have an incomplete metamorphosis. www.stephenville.tamu.edu/~fmitchel/dragonf ly/photo/aumb_2w.htm • 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 www.stephenville.tamu.edu/~fmitchel/dragonfly/photo/aumb_2 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 www.nysaes.cornell.edu/ent/biocontrol/info/primer.html#anatomy 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. Pictures • (All butterflies pictures) The Butterfly Guide, www.butterflies.com/guide.html • Aeshnidea; Digital Dragonflies, www.stephenville.tamu.edu/~fmitchel/drag onfly/photo/aumb_2w.htm • Insect Biology and Ecology: a primer; Biological control: A guide to natural enemies in North America; Weeden, Shelton, and Hoffmann; www.nysaes.cornell.edu/ent/biocontrol/info/ primer.html#anatomy