Effects of differentPhilosamia ricini(Lepidoptera: Saturniidae) cold storage periods onOoencyrtus pityocampaeandOoencyrtus kuvanae(Hymenoptera: Encyrtidae) rearing

Abstract

AbstractOoencyrtus pityocampaeandOoencyrtus kuvanaeare egg parasitoids that are considered potential candidates for the control of different pest species through inundative release. The aim of this study was to assess the effects of different cold-storage periods ofPhilosamia ricinieggs (host) on the rearing parameters ofO. pityocampaeandO. kuvanae. Host eggs were stored at 3 °C, and a factorial experiment involving two parasitoid species, nine host storage periods (1, 5, 10, 15, 30, 45, 60, 75 and 90 days) and a control, and two host ages (1 and 2 days) was conducted, with 10 replications including 40-P. ricinieggs each. Adult emergence, development time, longevity, and fecundity were investigated. The parasitoid adult emergence percentage significantly varied with storage duration. These values were lower inO. kuvanaethan inO. pityocampae. The development time ofO. kuvanaeprogeny increased in both host age groups except in the 1-day storage period subgroup. However, the development times of the progeny ofO. pityocampaereared on one-day-old eggs stored for 5, 10, 60, and 75 days were increased, and the development times of the progeny ofO. pityocampaereared on 2-day-old eggs stored for 45 and 90 days were increased. The longevity of the F1 progeny ofO. kuvanaewas negatively affected by storage time. There was no difference in the longevity of the F1 progeny ofO. pityocampaecompared to that of the control. Additionally, the fecundities of the F1 progeny ofO. pityocampaeandO. kuvanaewere 54.7 and 47.0 offspring/female, respectively. These results provide useful information for guiding the development of mass rearing methodologies for both parasitoid species.