ARS | Publication request: FACTORS THAT INFLUENCE THE DESICCATION TOLERANCE AND STORAGE STABILITY OF BLASTOSPORES OF THE ENTOMOPATHOGENIC FUNGUS PAECILOMYCES FUMOSOROSEUS

Submitted to: Society for Invertebrate Pathology Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: August 11, 2005
Publication Date: August 1, 2005
Citation: Jackson, M.A., Cliquet, S., Erhan, S.M., Connick Jr, W.J. 2005. Factors that influence the desiccation tolerance and storage stability of blastospores of the entomopathogenic fungus Paecilomyces fumosoroseus [abstract]. Society for Invertebrate Pathology Annual Meeting. Paper No. MC3, p. 79.

Technical Abstract: The survival of blastospores of Paecilomyces fumosoroseus during drying and storage was dependent on nutrition during growth, drying protocols and amendments, and storage conditions. The desiccation tolerance of blastospores of P. fumosoroseus was enhanced if the liquid production medium contained high concentrations of available nitrogen. During freeze-drying, sugars such as glucose, sucrose, and lactose improved desiccation tolerance while storage stability was enhanced by the addition of whole milk or bovine serum albumin. In air-drying experiments, the use of moist air (RH >65%) during drying enhanced the storage stability of blastospores of P. fumosoroseus. Under appropriate air- or freeze-drying conditions, blastospore survival after drying is 70-90%. Storage for 1 year at -20 deg C resulted in no significant loss in blastospore viability for freeze-dried preparations. When air-dried P. fumosoroseus blastospores were stored under vacuum at -4 deg C, 1 year storage resulted in no loss in blastospore viability with only a 40% loss in viability after 2 years’ storage. These studies have shown that liquid culture-produced blastospores of P. fumosoroseus can survive drying and remain viable during long-term storage if appropriate conditions are used in the production and stabilization of these propagules.