This award supports cooperative research on altered virulence of baculovirus as a biocontrol agent. The research will be conducted by James Maruniak of the University of Florida and Octavio Pavan at the University of Campinas in Brazil. They will attempt to understand the molecular changes in the viral DNA that result in a significant increase in the virulence of the velvetbean caterpillar baculovirus when it was serially passed to the sugarcane borer. The virus will be plaque-purified in insect cell cultures at Florida. The viral DNA will be purified and analyzed by restriction enzymes and compared with the parental virus DNA restriction profiles. Changes will be located on the parental virus physical DNA map already constructed at the University of Florida. The host range and virulence will then be measured in insect cell lines and bioassayed in velvetbean caterpillars and sugarcane borers at the University of Campinas. This research on the virulence of baculovirus to insect complexes on multiple crops is significant because this is one of the factors which has limited the use of biological pesticides. The information developed can be used to increase the virulence to insect pests by genetic manipulation of this EPA-registered virus. Dr. Pavan will come to Florida to learn the restriction methods and gene-mapping along with two students to do the viral DNA work. Dr. Maruniak has already prepared the physical map of the parental virus genome and will observe the insect assays in Brazil. He has the molecular background to enable him to locate the genomic changes. This is a highly desirable collaboration between a U.S. molecular virologist and a Brazilian entomologist with practical field experience. The insects are pest species in both countries and the virulence information will be applicable to other pathogen-pest complexes in the U.S. and Brazil.
