Life history traits of the parasitoid Goniozus legneri parasitizing Tuta absoluta larvae: assessing the viability of integrating biological control and inherited sterility

Abstract

The tomato leafminer, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), represents a major threat to tomato crops worldwide. The ectoparasitoid Goniozus legneri Gordh (Hymenoptera: Bethylidae) parasitizes T. absoluta larvae, while inherited sterility (IS) is an environmentally friendly option for controlling lepidopteran pests. This study aimed to elucidate the life history traits of G. legneri when parasitizing and feeding on T. absoluta larvae from untreated parents versus broods of irradiated parental males, exploring the potential integration of this parasitoid and IS for T. absoluta control. Overall, there were no significant differences in biological traits between treatments, except for the number of larvae killed per female and female longevity, both of which were higher in females feeding on larvae descended from irradiated parental males. Developmental time and survival of preimaginal stages showed no significant differences between the origins of T. absoluta larvae studied. Compared with other hosts of G. legneri, the parasitoid produced fewer offspring and showed suboptimal biological parameters when developed on T. absoluta. In conclusion, relying solely on G. legneri for T. absoluta control, either independently or in conjunction with IS, is not recommended. Nonetheless, exploring its combination with other techniques, such as the use of pheromone traps or biorational insecticides, merits further investigation.