Advertisements
Advertisements
प्रश्न
Explain the methods of controlling insect pests.
Advertisements
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).
APPEARS IN
संबंधित प्रश्न
Why are manures and fertilizers used in fields?
What are the advantages of inter-cropping?
Name three most important nutrients required for plant growth.
During the downpour in a village, the rain water carried away excess of nitrogenous and other compounds present in the soil to a pond. How will they affect the growth of algae and phytoplankton in the pond ?
How does excessive irrigation lead to soil salinity ?
Why water should be used judiciously ?
Write about three main criteria which should be considered while selecting the crops for rotation?
Explain various effects of weeds on crop plants.
Define irrigation. Why is irrigation of crops essential? Mention the harmful effects of excessive irrigation.
Explain the various preventive measures against insect pests.
