Control of insect pests in grains stored in insecticide-impregnated jute bags

Five chemicals, commonly used for grain fumigation, were injected into grain stored under non‐airtight conditions, in insecticide‐impregnated jute bags. The effect of the chemicals on the insects present in the grain was studied arid it was found that ethylene dibromide, when used at the rate of 10 c.c. per 2Oo‐lb. bag, completely controlled the insects. Injection of the chemical in either horizontally or vertically placed bags and at one or two places in the same bag gave similar results. For bags arranged in stacks, a dose of 7 1/2 c.c. of the chemical per 200‐lb. bag was found necessary for obtaining complete mortality of the insects. Injection of ethylene dibromide into unimpregnated bags also removed the insects from the bags, but the results suggested that some insects escaped death. The quantities of the chemical sorbed by the grain are mentioned and shown to be within the permissible limits.