Measuring parasitoid carbohydrate levels to improve biological control

Lifetime carbohydrate levels were compared in the laboratory between unfed and honeyfed Microctonus hyperodae (Hymenoptera Braconidae) a parasitoid of the Argentine stem weevil Listronotus bonariensis (Coleoptera Curculionidae) High performance liquid chromatography (HPLC) was used to analyse sugars in individual parasitoids and showed that fed and unfed parasitoids can be distinguished by measuring the total sugar levels Furthermore the fructose/total sugar ratio (f/T) of honeyfed M hyperodae was always higher than that of the unfed individuals This method should prove very useful for determining the nutritional status of fieldcollected parasitoids and for evaluating the benefits gained by parasitoids through the provision of floral resources in the field