DEVELOPMENT OF AN ARTIFICIAL DIET AND EVALUATION OF ARTIFICIAL OVIPOSITIONAL SUBSTRATES FOR THE IN VITRO REARING OF GONATOCERUS SPP. PARASITOIDS OF THE EGGS OF THE GLASSY-WINGED SHARPSHOOTER

• Author(s): Coudron, Thomas; Goodman, Cynthia; Jones, Walker; Leopold, Roger;
• Abstract: The intent of this project is to develop an in vitro rearing system for one or more of the three mymarid species of Gonatocerus currently being reared and released in California to control GWSS. A complete in vitro rearing system will include both a growth-enhancing artificial diet for larval and pupal development as well as a suitable oviposition substrate, or artificial egg. Initial studies will formulate artificial diets based on those developed previously for hymenopteran parasitoids, with an emphasis being placed on diets for other egg parasitoids. To accomplish this, Gonatocerus spp. eggs and/or larvae will be dissected from host eggs and placed in cell culture plates containing selected diets. Comparisons will be made between the development of parasitoids on these artificial diets, and those developing on the natural host. Developmental parameters measured will include extent of development, developmental time per stage, and weight. Once a promising diet is formulated, the reproductive rate and reproductive fitness of adults reared from these diets will be compared by using ovarian scoring and by assessing differences in fecundity and egg viability from crosses of diet-reared and hostreared adult wasps (Wittmeyer et al., 2001; Wittmeyer and Coudron, 2001). Refinement of the diet will be performed by modifying the diet based on its ability to meet the nutritional, phagostimulatory, and endocrine requirements of the parasitoid, and may include the additional of undefined components such as insect or cell-culture derived components. The suitability of artificial eggs, composed of different combinations of membranes and cupule sizes, will be evaluated statistically using pairwise comparisons of the proportion of artificial eggs and natural host eggs successfully parasitized by the same number of female Gonatocerus parasitoids (SAS, 2002).
• Publication Date: Dec 2004
• Journal: 2004 Pierce's Disease Research Symposium