Project Number: 1275-22000-219-00
Project Type: Appropriated

Start Date: Oct 01, 2003
End Date: Aug 31, 2005

Objective:
This project is concerned with insect viruses and cell culture systems, primarily as they relate to the field of insect pathology for biological control and is separated into three general objectives: 1) the development of new technologies for the production and application of insect viruses, focusing in particular on enhancing agents, alternative virus species, molecular characterization and manipulation of viruses, and the evaluation of new and existing cell lines for productivity and study of insect viruses and other pathogens. Our current interest is on a number of baculoviruses that infect a variety of insect pests, mostly in the family Noctuidae. 2) Develop new cell culture systems from economically important insect species. The initial efforts will be with insects of interest to other researchers in the Insect Biocontrol laboratory as well as other ARS laboratories around the country and will also include further efforts with midgut stem cell cultures. And 3) molecular characterization and analysis of biological activity of polydnaviruses including genome analysis for developing a gene vectoring system.

Approach:
Technical improvements in virus production will target existing and new cell culture systems to study insect pathogens of interest in the control of insect pests. In particular, nucleopolyhedroviruses from moth and mosquito species will be studied. Larval bioassays and field studies will be used to evaluate different virus species and the effects of additives such as stilbene brighteners as enhancers. Methods and culture media suitable for specific insect cell lines will be utilized to establish cultures from insect pests of vegetables, medical interests (mosquitoes), and beneficial insects (honey bees). Various cultural conditions (varied temperatures, conditioned medium, etc.) will be used in these efforts. Additionally, a system previously developed in this laboratory for culturing the midgut of pest insects will be used to help discern factors involved in the proliferation, differentiation, and death of these cells. The morphological and molecular composition (nucleic acid and protein profiles) of a polydnavirus from Glyptapanteles indiensis will be used to identify viral genome regions of significance for developing the polydnavirus-based vector to use in an expression system and/or gene transfer into beneficial or pest insects.