GK
ECOLOGY BIODIVERSITY CONSERVATION ENVIRONMENTAL ISSUES
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Lindane
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Parathion
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Carbaryl
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Monocrotophos
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Detailed explanation-1: -Though desirable in the season of application, its persistence in the soils may affect the crop growth and yield. Benzene Hexachloride(BHC) is a chemical compound with several stereoisomers of which one is an insecticide called Lindane and the by-product is -hexachlorocyclohexane-the pesticide.
Detailed explanation-2: -The simplest view of pesticide persistence is that of no loss at all. Repeated applications simply raise the concentration in the soil in stepwise fashion for as long as the practice continues. Arsenic, mercury, and lead approach this extreme of persistence more closely than do any of the synthetic organic pesticides.
Detailed explanation-3: -Dieldrin is an example of organochlorines and most persistent in soil. Most importantly dieldrin is five times more toxic than DDT.
Detailed explanation-4: -Hexachlorocyclohexane (lindane) DDT and related compounds DDE and DDD. Cyclodienes (aldrin, heptachlor, and others) Mirex and chlordecone.
Detailed explanation-5: -The mean half-times estimated in soils from all plots over 11 years were 5.1 years for dieldrin, 3.2 years for all DDT compounds combined, and 3.2 years for heptachlor epoxide.