| The parasitical efficiency of Pachycrepoideus vindemmiae (Rondani) (Hymenoptera: Pteromalidae) parasitized on Bactrocera dorsalis (Hendel) in different mediums and different extreme temperature was studied in the laboratory.The frequency and time for pteromalids to visit fly pupae were also observed.The results showed that the parasitism rate of pteromalids could be affected by the depth of fly pupation and the characteristic of medium.In the same medium, the parasitism rate was decreased when the depth of fly pupation was increased.In the range of sand grains with 0～2.21mm diameter, the parasitism rate was the highest as the pupae of Bactrocera dorsalis pupated in the sand grains wigh 1.14～1.81mm diameterAfter being treated female adults with 50℃.the parasitism rate of the first day female adults increased in contrast with control, and the emergence rate and sex ratio (♀:♂) of the secondary generation were not changed, but the longevity of female adults would be shortened.After being treated female adults with 4℃, the parasitism rate of the first day female adults decreased, however the sex ratio (♀:♂) of the secondary generation increased and the longevity of female adults would be longer.Under conditions of 28±1℃and 70±5% RH, both the frequency and the time pteromalids visited fly pupae within 10: 00～11: 00am and 15: 00～16: 00pm were more than other periods.
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