Insect & Mite Pest Management

1. Insect & Mite Pest Management • Pest managers rarely use the term pest control or eradication—because we have never been ableto control insect and mite pests permanently.

2. Insect and Mite Pest Management - Modes of Entry • Stomach poison refers to materials that enter by mouth & kill absorbtion via the digestive tract. • Some insecticides can be absorbed into plant tissues (translaminar systemic) and/or transported through vascular systems (translocated systemic). • Systemic insecticide residues can remain in the plant tissues eaten by humans.

3. Insect and Mite Pest Management - Modes of Entry • Contact poison refers to materials that enter the body directly through the pest’s cuticle. • Some have to be applied to the pest—others have sufficient residual action that residues are pickedup as the pest walks across treated surfaces. • Inhalants are applied as fumigants, and inhaled as a vapor or dust by the insect or mite. • Fumigants are generally used in enclosed spaces. • Some can also be used in soil if the surface is sealed with water or an impermeable covering like plastic sheeting.

4. Insect and Mite Pest Management - Modes of Action • Neural Disruption—major neural systems affected are sodium pump channels & neural transmitters. • Cellular Metabolic Disrupters—disrupt different metabolic pathways of a cell.

5. Insect and Mite Pest Management - Modes of Action • Cell Membrane Disruption—oils & soaps disrupt the lipoprotein matrix of cells, causing them to lose their contents and cease functioning. • Though considered impermeable, the insect cuticle is filled with microtubules that lead to the underlying cells—which are destroyed by oils and soaps.

6. Insect and Mite Pest Management - Modes of Action • Hormone Disruption—pesticides can mimic insect hormones or disrupt normal function of hormones. • These are called insect growth regulators (IGR). • Many of these have specific targets, which makes them safe to use for predatory insects & mites.

7. Insect and Mite Pest Management - Modes of Action • Pheromones—chemicals insects normally use to communicate with each other—can used to disrupt mating.

8. Insect and Mite Pest Management - Modes of Action • Dessicants—cause insects to lose water faster than they can replace it. • Desiccants work best in dry environments.

9. Insecticides Classified by Chemistry • A great many chemicals have been used for controlling insects— • Some were so harmful to humans, animal life, andthe environment that their use is no longer permitted. • In the U.S. insecticides must be approved/registered by various agencies before they can be used. • Use is confined to certain plants, times & concentrations. • Residues on food or feed crops exceeding fixed tolerances subject products to seizure & destruction.

10. Insecticides Classified by Chemistry - Inorganic • Inorganic compounds—arsenic, phosphorus, fluorine and sulfur compounds. • Use of these has diminished greatly over time.

11. Insecticides Classified by Chemistry - Organic • Organic compounds—Plant derivativeslike pyrethrum, rotenone, nicotine, and an extract from the neem tree. • Others could possibly be developed, given sufficient demand.

12. Insecticides Classified by Chemistry - Organic • Synthetic organic chemicals. • Chlorinated hydrocarbons such as DDT, discovered in Germany in 1874. • Organic phosphates, developed near the end of WW II, found to have good insecticidal properties. • Carbamates—Carbaryl was first widely-used—with low mammalian toxicity & short residual action.

13. Insecticides Classified by Chemistry - Organic • Synthetic organic chemicals • Pyrethroids—fairly new class of insecticides that mimic properties of pyrethrins such as low mammalian toxicity. • Neonicotinyls—a recent class of insecticides that blockthe synoptic transmission of insect nerves. • Spray oils—prepared by distillation/refining of mineral oils, an oil fraction relatively nontoxic to plants, lethal to insects. • Microbial insecticides—some insects are susceptible to certain toxins produced by bacteria, fungi, and viruses