[The determination of toxicity of four insecticides on ground squirrel flea]

This paper reports the results of toxicological effect of four insecticides on Citellophilus tesquorum sungaris. The toxicity of Deltamethrin was the strongest in four insecticides, DDVP & DDT were stronger than 1-(3,4-dichlorophenyl)-2,2,2-trichloroethyl acetate. For the LD50 of four insecticides on suckling blood female flea of two-day-age, were 1.17 x 10(-6) micrograms per flea 1.20 x 10(-3) micrograms per flea 1.25 x 10(-3) micrograms per flea & 3.46 per flea respectively. The data showed that there were marked differences in the susceptibility to the same insecticide between unsuckling blood fleas and suckling blood fleas. Male fleas were more susceptible than female fleas in suckling blood fleas.