Pesticides are used for controlling pests. These chemicals are applied by spraying or by fumigation. Spraying is done inside the storage structure before arrival of fresh stock. This is done for disinfecting the storage structure. Chemicals used are malathion or pyrethrum.
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Fumigation is done to check the growth of insect population in stored grains. Fumigants are volatile chemicals which vaporize quickly and kill the insects without affecting the grains. Ethylene dibromide and aluminium phosphide are used as fumigants.