Improvement In Food Resources — Science STD 9 — Question

The ways by which the insects attack the crop plants are:

1. The chewing insects destroy all sorts of crop plants. They cut the root, stem and leaf of the crop plants by the help of their chewing mouth parts.
2. Sucking insects suck the cell sap from various parts of the plant. They make fine punctures in the skin of plants with their needle - like, hollow beaks and suck the sap.
3. The internal feeders live inside the plant parts. They make holes in the developing grains.