Reproduction of Ooencyrtus submetallicus (Hymenoptera: Encyrtidae) in egg densities of Euschistus heros (Hemiptera: Pentatomidae)

Abstract

Abstract Knowledge about the ideal host ratio per female parasitoid reared in glass tubes is important for obtaining descendants with better biological quality. The study aimed to evaluate the reproduction of Ooencyrtus submetallicus (Hymenoptera: Encyrtidae) females in egg densities of Euschistus heros (Hemiptera: Pentatomidae) to find the most adequate relationship between parasitoids and hosts aiming at the parasitoid multiplication. The experiment was conducted with E. heros eggs at densities (parasitoid:host) of 1:3, 1:6, 1:9, 1:12, 1:15, or 1:18 with 24 hours of parasitism by O. submetallicus. The parasitoid females and the egg carton were placed in glass tubes and kept in a climate-controlled chamber. The percentage of parasitism was affected by the nonparasitised eggs. The emergence of adult parasitoids, number of parasitised eggs, number of individual parasitoids emerging per egg, the length of the parasitoids’ posterior tibiae, and the parasitoids’ longevity, life cycle, and sex ratio were not affected by the different densities of nonparasitised eggs subjected to treatments. Ooencyrtus submetallicus parasitised and developed in E. heros eggs in all evaluated densities, with 1:6 presenting the best combination of parasitoid and host.