Laboratory rearing of Cotesia urabae Austin and Allen (Hymenoptera: Braconidae), a biological control agent of Uraba lugens Walker (Lepidoptera: Nolidae)

Cotesia urabae (Hymenoptera: Braconidae) was released in New Zealand in 2011 for the biological control of the Eucalyptus pest Uraba lugens (Lepidoptera: Nolidae) (gum leaf skeletoniser). Methods for rearing C. urabae and its host under containment conditions are described. An intensive method was developed to allow tracking of individual female parasitoids and their progeny for use in host specificity testing experiments and to maximise the production of female offspring for culture maintenance. Of females paired using this method, 26.3% (35/133) were observed mating, and subsequently produced offspring that were 57.0% ± 5.9SE (n = 21) female on average. To maximise the use of parasitoids that were often in short supply, females that failed to mate with the intensive method were caged with multiple males and females. Of a sample of these females, 19.4% (6/31) produced female offspring (indicating mating had occurred). Refinement of a technique for maximising courtship and mating probability was critical to the success of this laboratory culture.