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प्रश्न
Explain the methods of controlling insect pests.
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उत्तर
Infestation of different types of insect pests can be controlled by the following methods :
- Root cutting types of insects are controlled by mixing insecticide in soil, e.g., chloropyriphos.
- Stem and leaf cutting and boring type of insects are controlled by dusting or spraying the contact insecticides, e.g., malathion, lindane and thiodan.
- All sap sucking insects can be controlled by spraying systemic insecticides e.g., dimethoate and metasystox. An insecticide entering the plant via the roots or shoots and passing through the tissues is called systemic. A systemic insecticide harmlessly penetrates the tissues of host plant and poison insects feeding on it (e.g., Aphids).
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