Submitted to: Government Publication/Report
Publication Type: Government Publication
Publication Acceptance Date: May 16, 2008
Publication Date: May 16, 2008
Citation: Smith, L. 2008. Development of artificial diet to rear internal-feeding insects to accelerate research on new biological control agents of yellow starthistle and other alien weeds. Government Publication/Report. University of California Exotic/Invasive Pests and Diseases Research Program - Final Report. 6pp. Interpretive Summary: Invasive alien weeds are an increasing problem in the United States. Classical biological control provides a cost-effective, environmentally benign method of achieving sustainable control of many of these invaders. Internal-feeding insects can be effective biological control agents of invasive alien weeds, but they are usually difficult to collect and rear. The development of effective diets and rearing systems could greatly aid the discovery and evaluation of root- and stem-feeding insects for biological control. We developed and tested a system for rearing adult insects from field-collected larvae that is useful for foreign exploration. We adapted a previously developed artificial diet for the purple loosestrife root weevil and tested the system on a well-studied root-feeding weevil of yellow starthistle. The method also works for a variety of other insects dissected from a variety of plant species. The diet transfer kit will aid the discovery and development of new internal-feeding insect biological control agents of invasive alien weeds.
Technical Abstract: We demonstrated that an artificial diet that was previously developed to rear the purple loosestrife root weevil, Hylobius transversovittatus, can be effective for completing the development of larvae that are dissected out of plants. We used this diet to rear to adult stage larvae and pupae of the yellow starthistle rosette weevil, Ceratapion basicorne, that were dissected from yellow starthistle plants in Turkey. The diet ingredients were modified to reduce microbial contamination, the container size and style of top were optimized for ease of use and to reduce diet desiccation, and gouging the diet at the container sides facilitated insect survival and permitted easy monitoring of developmental progress. The diet kit successfully reared adults from larvae of other species of root- and stem-boring weevils from spotted knapweed (Centaurea stoebe, Asteraceae) and prangos (Apiaceae), and a stem-boring chloropid fly from tall whitetop (Lepidium latifolium Brassicaceae). The diet was not successful for rearing adults of the yellow starthistle stem-boring flea beetle, Psylliodes chalcomera. The diet could be further modified to better suit insects that feed in plant parts with different physical and chemical properties.