Write the modes by which insects affect the crop yield.
Following are the different modes by which insect pests affect the crop yield.
(i) Cutting: Some insect pests cut different plant parts; like leaves, fruits and flowers. Thus, they damage the plant. Damaged leaves would result in lower rate of photosynthesis. Damaged flowers will result in less production of seeds.
(ii) Borers: Some pests make a burrow in a plant part and live inside. There can be stem borers or fruit borers. These pests utilize resources from plants.
(iii) Suckers: Some pests use their proboscis to suck cell sap from plant parts.
