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Insect & Mite Pest Management. Pest managers rarely use the term pest control or eradication —because we have never been able to control insect and mite pests permanently. Insect and Mite Pest Management - Modes of Entry.
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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.
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.
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.
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.
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.
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.
Insect and Mite Pest Management - Modes of Action • Pheromones—chemicals insects normally use to communicate with each other—can used to disrupt mating.
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.
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.
Insecticides Classified by Chemistry - Inorganic • Inorganic compounds—arsenic, phosphorus, fluorine and sulfur compounds. • Use of these has diminished greatly over time.
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.
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.
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