Effects of releasing two Diachasmimorpha longicaudata population lines for the control of Ceratitis capitata infesting three key host fruit species

Abstract

Exotic plants favor persistence and spread of the invasive medfly, Ceratitis capitata. Peach and orange are key host plants for medfly proliferation in Argentina. Consequently, actions to suppress medfly populations are taken, especially those performing augmentative releases of parasitoids. This study provides information on the capability of two population lines of the parasitoid Diachasmimorpha longicaudata to control medfly infesting the fruits of peach, as well as sour and sweet orange. One parasitoid line comes from non-irradiated larvae of wild medfly. The other comes from irradiated larvae of the Temperature Sensitive Lethal Vienna-8 medfly strain. The parasitoid host-finding ability in each aforementioned fruit species, the effectiveness of females to kill medfly larvae, the fruit height level preference for parasitoid foraging activity, and the influence of environmental conditions on parasitoid performance were compared and assessed. Parasitoids foraged for 48 h on fruits artificially inoculated with wild medfly larvae in field cages. Females of both parasitoid lines showed a similar effectiveness pattern, foraged efficiently on fruit at ground and canopy levels, and were able to overcome local climate conditions and to develop at least one new generation under natural environmental conditions. These outcomes may provide relevant information for the implementation of augmentative biological control against medfly.