At the same time, insecticides create problems of their own. For example, many species of the insects have expire resistant or immune to them, especially to DDT. Also, biologists have make out that excessive use or careless use of insecticides destroy many beneficial insects, birds and small mammals. In addition, some(a) insecticides, notably DDT, tend to persist in soil and pee and can eventually accumulate in body wind of fish, wildlife and humans. DDT also tends to combine with other chemicals in the soil, producing wise toxic compounds that are more harmful than DDT alone. These problems can be avoided, at least by the use of discriminating chemicals and synthetic sterilants, pheromones and growth-regulating hormones.
The phratryification of insecticides are done in several(prenominal) ways which include:
Systemic insecticides which are applied to the plant in question. The insects ingest the insecticide while feeding on the plant and die.
Contact insecticides are toxic to insects that come in contact with them. They are applied in small drops, ordinarily as aerosols.
Natural insecticides are extracts made by plants as a natural defence against inscests. Examples include Nicotine (barred in the US), pyrethrum and Neem.
There are two main types of insecticides namely the radical and inorganic insecticides.
1. Organic Insecticides: this is a very broad class of insecticide accounting for over 60% of insecticide use worldwide. They include Organochlorines, Organophosphates, Organosulfurs, Carbamates. Formamidines and others.
Organochlorines: these are insecticides that contain Carbon,...If you want to get a full essay, order it on our website: Ordercustompaper.com
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