Parasitizing efficiency of Tetrastichus howardi (Olliff) (Hymenoptera: Eulophidae) on Galleria mellonella (Linnaeus) (Lepidoptera: Pyralidae) larva and pupa

Abstract

Abstract Background This study evaluated the parasitizing efficiency of Tetrastichus howardi (Olliff) (Hymenoptera: Eulophidae) on the Galleria mellonella (Linnaeus) (Lepidoptera: Pyralidae) larvae and pupae. The sixth instar larvae and 48 h. old pupae were individually exposed for 24 h. to 15 newly emerged mated females of T. howardi. Following the emergence of parasitoids, observations were recorded on the percentage of parasitized and emergent pupae and larvae, life cycle duration, progeny, male and female emergence, sex ratio, longevity of male and female and adult per mg weight. Results In both pupal and larval, parasitization and emergence were 100%. The pupa produced 438.56 progenies, with 394.76 females and 43.2 males and a sex ratio of 0.89. In larvae, 311.93 progenies emerged, with 259.83 females and 53.0 males and a sex ratio of 0.83. The T. howardi life cycle duration was 17.66 days in pupae and 20.13 days in larvae. Longevity of female and male progeny that emerged from pupae and larvae was 15.83, 13.40, and 10.40, 8.76 days respectively. The overall progeny production in pupae and larvae was 2.75 and 1.60 individuals per mg body weight, respectively. Conclusions The highest parasitism as well as biological and reproductive development of T. howardi in G. mellonella pupae and larvae suggests that this host could be employed as an alternate host for mass multiplication.

Keywords

• Biological control
• Tetrastichus howardi
• Galleria mellonella
• Larval and pupal parasitism