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Comparative study of parasitic capacity and longevity of three local Trichogramma spp.; T. cordubensis and T. euproctidis from arid area and T. borarachae from a semi-arid area, collected from olive groves in Egypt, was carried out under laboratory conditions at 25 +/- 0.5 degrees C. Significant differences were found among the parasitic capacity of the tested Trichogramma spp. It was 80.1 +/- 3.5 for T. borarachae versus 60.2 +/- 2.5 for T. cordubensis and 73.2 +/- 2.7 for T. euproctidis. In all species, parasitism was highest in the first day. Longevity of Trichogramma females was studied by exposing freshly emerged wasps to different feeding regimes as follows: 1) combination of honey and host eggs, 2) honey only and 3) no honey or hosts. The longevity experiments indicated that feeding conditions significantly affected the survival period of the wasp females. In all species, the longevity of honey-fed non ovipositing females was significantly longer. In the absence of food source all species showed the shortest longevity. In general, parasitoid longevity under each feeding condition was species dependent.