Canadian Forest Service Publications
Parasitoids reared from the obliquebanded leafroller (Lepidoptera: Tortricidae) infesting raspberries. 1999. Li, S.Y.; Fitzpatrick, S.M.; Troubridge, J.T.; Sharkey, M.J.; Barron, J.R.; O’Hara, J.E. The Canadian Entomologist 131: 399-404.
Issued by: Atlantic Forestry Centre
Catalog ID: 18489
CFS Availability: Order paper copy (free)
Fourteen species of parasitoids (13 hymenopterans, 1 dipteran) were reared from larvae or pupae of the obliquebanded leafroller, Choristoneura rosaceana (Harris), collected from commercial raspberry fields in the Fraser Valley, British Columbia, Canada, over 3 years. Levels of parasitism ranged from 5 to 15%. Among these 14 species, five represent new host records. A polyembryonic wasp, Macrocentrus nigidorsis Viereck (Hymenoptera: Braconidae), was the most abundant parasitoid. External feeding on the final host instar is obligatory for M. nigridorsis to complete development. On average, each parasitized host larva produced about 36 M. nigidorsis, in either unisexual or mixed-gender groups. Overall male to female sex ratio was 1:4. Head capsules of mature parasitized host larvae were significantly larger than those of unparasitized ones, suggesting that C. rosaceana larvae parasitized by M. nigridorsis might have an extra larval stage.