CHEMICAL CONTROL Flashcards
___based on substances that are toxic (poisonous) to the pests involved.
Chemical control
The _____ around 1200 BC, used ___ and ____ to destroy parasites.
Chinese
lime and wood
The Romans used ____ a substance derived from crude oil.
sulphur and bitumen,
Any substance or mixture of substances, intended for preventing, destroying, or mitigating any pest, or intended for use as a plant growth regulator, defoliant or desiccant.
Pesticides
Diff types of pesticides
Insecticide
Herbicide
Fungicide
Nematicide
Rodenticide
Bactericide
Algaecide
Desiccant
Miticide
Lampricide
Avicide
Defoliant
Molluscicide
Piscicide
Kills broad range of pests, usually refers to insecticides, fungicides. and bactericides
Broad Spectrum
Kills by contacting pest
Contact Poison
Effective against pathogen that has already infected the crop
Disinfectant (Eradicant)
Inhibits germination of weed seeds, fungus spores, bacterial spores.
Germination Inhibitor
Kills broad range of pests and/or crop plants, usually used in reference to herbicides.
Nonselective
Interferes with nervous system function
Nerve Poison
Protects crop if applied before pathogens infect the crop
Protectants
Repels pest from crop or interferes with pest’s ability to locate crop
Repellents
Absorbed and translocated throughout the plant to provide protection
Systemic
Kills after ingestion by an animal
Stomach Poison
a substance or a mixture of substances which repel, destroy, or mitigate any insect that is considered or declared pest. This can be classified based on the mode of entry, origin. pattern of stability. spectrum of activity, and degree of toxicity to mammals.
Insecticides
-the materials exert their toxic action only after they have been introduced into the alimentary canal through feeding on treated substrates. Some of the examples are arsenicals. and fluorides.
Stomach insecticides
these insecticides penetrate the insect exocuticle and could then be transported to the site of action via the circulatory system. Some of the examples are nicotinoids, rotenoids and most of the synthetic insecticides.
Contact insecticides
these insecticides are used for the control of insects in both plants and animals. When applied to the animal the toxicant is translocated to the untreated parts in concentration that makes the final translocation sites toxic to insects.
Systemic insecticides
insecticides that seldom contain carbon. Arsenicals and fluorides are some of the examples.
Inorganic insecticides
these insecticides are characterized by organic carbon to carbon bondings.
Organic insecticides
these are the insecticides that stay in the environment and control the pest insects for several months and continuously to get into the food chains. The DDT for mosquito control, chlordane for termites control are some of the examples.
Persistent insecticides
these are the insecticides that stay in the environment and control pest insects for a few days only because the insecticides are easily detoxified by any detoxifying factors like sunlight, water, temperature and microorganisms. The insecticides in this category are Dipel, Xentari, and some Pyrethroid insecticides like Sumicidin and Cymbush.
Non-persistent insecticides
these are insecticides that are toxic to 1 or to some but not the majority of the pest insects in the ecosystem. Some of the examples are Dipel, Thuricide HP. Confidor, Nomolt and Perimor.
Selective insecticides
these are the insecticides that are toxic to a wide range of insects/organisms including the beneficial insects. Tamaron, Selecron. Pennant. Lorsban are some of the examples of non-selective insecticides.
Non-selective/Broad spectrum insecticides
a Swiss entomologist, was awarded the Nobel Prize in
Medicine for his lifesaving discovery of
DDT (1939) as an insecticide useful in the control of malaria, yellow fever and many other insect-vectored diseases.
Dr. Paul Muller
The oldest group of the organochlorines is the ____ , which included DDT, DDD. dicofol,
ethylan, chlorobenzilate, and methoxychlor. DDT is
probably the best known and most
notorious chemical of the 20th century.
diphenyl aliphatics
The____ are insecticides that contain carbon (thus organo-), hydrogen, and chlorine. They are also known by other names: chlorinated hydrocarbons, chlorinated organics, chlorinated insecticides, and chlorinated synthetics.
organochlorines
act as insect growth regulators (IGRs), they interfere with chitin synthesis.
Their greatest value is in the control of caterpillars and beetle larvae.
BENZOYLUREAS
Some 10,000 species of the more than I million species of insects are crop-eating, and of these, approximately____ species worldwide cause most of the insect damage to man’s crops. in the field and in storage.
700
Humanoids have been on earth for more than 3 million years, while insects have existed for at least ____ million years.
250
Historians have traced the use of pesticides to the time of Homer around 1000 B.C.. but the earliest records of insecticides pertain to the burning of “______ “ (sulfur) as a fumigant.
“brimstone”
This person _____ recorded most of the earlier insecticide uses in his Natural History. we find a variety of materials used with questionable results: extracts of pepper and tobacco, soapy water, whitewash, vinegar, turpentine, fish oil, brine, lye among many others.
Pliny the Elder
