If a genetic sexing strain of Ceratitis capitata could be used to produce sterile males and to rear parasitoids at the same time, significant amount of resources could be saved in comparison with the production of these two biological agents separately. We studied here the major biological parameters comparing two strains of the parasitoid Diachasmimorpha longicaudata, one of them reared on a wild type strain of C capitata: DL(+), and the other on a genetic sexing strain of C capitata: DL(sw). The mean longevity, fecundity, and sexual proportion of their respective offspring showed no significant difference. Moreover, no difference was observed in population parameters such as mean generation time, net reproductive rate, finite rate of increase, doubling time, and intrinsic rate of increase. The biological parameters of other artificially reared parasitoids in the Tephritidae family are reviewed, and the conclusion is reached that, rearing the parasitoid on this particular genetic sexing strain of C capitata does not produce any negative effect on the biological parameters studied. [copyright] 2005 Elsevier Inc. All rights reserved. none