Influence of Distance from the Host on Parasitisation by (Szépligeti) (Hymenoptera: Braconidae).

The olive fruit fly, , is considered the main olive pest worldwide, and has been the target of biological control programmes through the release of the braconid parasitoid . Laboratory tests were performed to evaluate the influence of distance from the host on parasitisation, placing larvae of the substitute host at seven distances (0, 0.5, 1, 1.5, 2, 2.5, 3 mm) and four different time periods (7, 15, 30, 60 min). Moreover, field collected olives of Ogliarola Barese cultivar infested by were exposed to females to confirm its ability to parasitise in small olives. oviposition was inhibited at 2.5 and 3 mm due to the ovipositor length of the parasitoid females (2.7 mm). Hosts were easily parasitised at distances between 0 and 1.5 mm. The thin fruit pulp (up to 3.5 mm) of field collected olives allowed the parasitisation to occur also in mature fruits. At the best combination distance/time (0 mm, 30 min), tests performed with different larvae/parasitoid female ratio showed an increasing emergence of (from 20% to 57%) with larvae/parasitoid ratio increasing from 0.11 to 0.74. The results of the present study might optimise the mass rearing of , through a proper setting of its parameters, such as the host/parasitoid ratio, exposure distances, and interaction time.