Several factors may limit the utilization of microbial insecticides, including the time required to cause insect mortality, which is longer than conventional pesticides. Developing correct formulations, containing appropriate carriers for host infection, are considered fundamental for the successful utilization of entomopathogenic fungus on a large scale (Faria and Wraight 2007; Goettel and Roberts 1992). Vegetable oil may be used as a component in formulation for spore protection from ultraviolet radiation (Alves et al. 1998; Inglis et al. 1995; Moore et al. 1992) and to increase the effectiveness and virulence of the fungus against the arthropod pests when compared to aqueous formulations (Kaaya and Hassan 2000).