Submitted to: Invertebrate Pathology International Colloquium Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: September 7, 1996
Publication Date: N/A
Technical Abstract: Numerous isolates of the entomopathogenic fungus Paecilomyces fumosoroseus are being developed as microbial control agents for various soft-bodied insects including the silverleaf whitefly (Bemisia argentifolii), the greenhouse whitefly (Trialeurodes vaporariorum), and the Russian wheat aphid (Diuraphis noxia). The successful commercialization of P. fumosoroseus as a bioinsecticide requires, in part, the development of a cost-effective method for the production of stable, infective propagules. Our previous studies identified nutritional conditions which supported the production of desiccation tolerant blastospores of P. fumosoroseus in liquid culture. In this study, culture conditions were identified which reduced fermentation times and improved blastospore yield. Basal media with vitamins and trace metals containing greater than 20 g/L glucose and 13 to 40 g/L Casamino acids maximized the production of desiccation tolerant blastospores of P. fumosoroseus. When liquid media containing 80 g/L glucose and 25 g/L Casamino acids was inoculated with a 3-day-old preculture of P. fumosoroseus (1% v/v), yields of more than 1 x 10**9 blastospores/mL were obtained after 2 days growth. Numerous carbon and hydrolyzed protein sources were substituted for glucose and Casamino acids, respectively, without loss in blastospore yield. These results suggest that liquid culture fermentation has commercial potential for the production of high concentrations of blastospores of P. fumosoroseus.