title: Development of Spalangia cameroni and Muscidifurax raptor (Hymenoptera: Pteromalidae) on live house fly (Diptera: Muscidae) pupae and pupae killed by heat shock, irradiation, and cold.
abstract: The objective of this study was to evaluate the suitability of killed house fly (Musca domestica L) pupae for production of two economically important pupal parasitoids. Two-day-old fly pupae were subjected to heat shock treatments of varying temperatures and durations in an oven at >or=70% RH; exposure to temperatures of 55 degrees C or higher for 15 min or longer resulted in 100% mortality. Exposure to 50 degrees C resulted in 40 and 91% mortality at 15 and 60 min, respectively. All (100%) pupae placed in a -80 degrees C freezer were killed after 10-min exposure; exposure times of <5 min resulted in <21% mortality. Progeny production of Spalangia cameroni Perkins and Muscidifurax raptor Girault and Sanders (Hymeoptera: Pteromalidae) from pupae killed by heat shock or 50 kR of gamma radiation was not significantly different from production on live hosts on the day when pupae were killed. Freeze-killed pupae produced 16% fewer S. cameroni than live pupae and an equivalent amount of M. raptor progeny on the day when pupae were killed. When killed pupae were stored in freezer bags at 4 degrees C for 4 mo, heat-killed, irradiated, and freeze-killed pupae remained as effective for production of M. raptor as live pupae. Production of S. cameroni on heat-killed and irradiated pupae was equal to parasitoid production on live pupae for up to 2 mo of storage, after which production on killed pupae declined to 63% of that observed with live pupae. Production of S. cameroni on freeze-killed pupae was 73-78% of production using live pupae during weeks 2-8 of storage and declined to 41 and 28% after 3 and 4 mo, respectively. Killing pupae by heat shock provides a simple and low-cost method for stockpiling high-quality hosts for mass-rearing both of these filth fly biological control agents.
authors.affiliation: USDA-ARS, Center for Medical, Agricultural and Veterinary Entomology, 1600 SW 23rd Dr., Gainesville, FL 32608, USA. cgeden@gainesville.usda.ufl.edu
authors.forename: C J
authors.initials: CJ
authors.lastname: Geden
authors.forename: P E
authors.initials: PE
authors.lastname: Kaufman
mesh_terms: D000818:Animals; D001947:Breeding / Q000379:methods; D003080:Cold Temperature; D005720:Gamma Rays; D006358:Hot Temperature; D006793:Houseflies / Q000254:growth & development / Q000469:parasitology* / Q000528:radiation effects; D010572:Pest Control, Biological; D011679:Pupa / Q000469:parasitology / Q000502:physiology / Q000528:radiation effects; D012098:Reproduction; D014863:Wasps / Q000254:growth & development / Q000502:physiology*