A strategy for genetic modification of Epinotia aporema Granulovirus.

FERRELLI, ML; BIEDMA, M.E; SALVADOR, R; SCIOCCO-CAP, A; ROMANOWSKI, V

Quebec

Congreso; 40th Annual Meeting of the Society for Invertebrate Pathology and the 1st International Forum on Entomopathogenic Nematodes and Symbiotic Bacteria.; 2007

Epinotia aporema (Lep. Tortricidae) is a major pest of legume crops in South America. A granulovirus (EpapGV) characterized in our laboratory exhibits a great potential as bioinsecticide; however it cannot compete with chemical insecticides when the average temperature is under 20oC. In this context, there is room for improvement of its biological performance using genetic engineering. This type of manipulation proved to be difficult to manage without a susceptible cell line. Therefore, we set out to construct a bacmid by inserting a miniF replicon into EpapGV DNA. The egt gene has been previously characterized and its deletion in other baculoviruses led to an enhancement of the speed of kill. Thus, a construct containing EpapGV egt 5? and 3? regions was generated to target the miniF sequences to this locus. The following steps required the introduction of the bacmid into E. aporema larvae. Transfection was first tested with authentic viral DNA isolated from granules. To set up the experimental protocols we used Anticarsia gemmatalis Nucleopolyhedrovirus (AgMNPV), because the availability of the susceptible cell line UFLAg-286 facilitated testing procedures. The propagation of EpapGV DNA in E. coli will simplify the generation of site-specific mutants both for basic studies and enhancement of insecticidal activity.