Question
Write the modes by which insects affect the crop yield.
✓
Answer
Some common insect pests of stored grain and their mode of infection are:
- Gram dhora or Pulse beetle (Callosobruchus maculatus) Its grubs, damage the stored gram.
- Rice weevil: (Sitophilus oryza) Both grub and beetle (adult) damage rice.
- Khapra or Wheat weevil: (Trogoderma granarium) Infests stored wheat.
- Grain and flour moth: (Sitotroga cerealella) Its caterpillars bore into grains of rice, wheat, barley, maize and jowa.
- Rust red flour beetle: (Tribolium castaneum) Both larvae and adult damage flour and flour products.
- Rice moth: (Corcyra cephalonica) Larvae damage rice and maize.
- Lesser grain borer: (Rhizopertha dominica) Both grub and adult (beetle) damage the grains, reducing them to perforated shells.
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