Submitted to: Society for Invertebrate Pathology Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 9/6/1996
Publication Date: N/A
Technical Abstract: Several examples on the role of fungal volatiles as attractants to insects have been reported. One area that has not been as well studied is the emission of volatiles by entomopathogenic fungi and the role of these volatiles in attracting insects. We examined the headspace volatiles of two fungal entomopathogens, Beauveria bassiana strain AF4; Ciba, Vero Beach, FL, and Paecilomyces fumosoroseus (strain 4491; M. Jackson, NCAUR) when grown in corn and in potato dextrose agar (PDA). We hypothesized that it would be advantageous to fungal entomopathogens to produce volatiles attractive to insects as a way to disseminate the fungus. B. bassiana produced acetaldehyde, ethanol, 2-methyl propanol, 3-hydroxy-2-butanone, 3-methyl-1-butanol, 2-methyl-1-butanol, and meso-2,3-butanediol. There were differences in the amount and presence of these constituents when grown in corn or potato dextrose agar (PDA). Ethanol reached the highest levels within two days after inoculation (46 ng/ml in the headspace over PDA and 22 ng/ml in the headspace over corn). All other components were detected at levels below 6 ng/ml. In contrast to B. bassiana, P. fumosoroseus did not produce any detectable volatiles. It is still unclear what role the volatiles from B. bassiana play in attracting insects. It might be possible that other hosts for the entomopathogen (e.g., rotting vegetation, wood, etc.) might result in the production of volatiles that are attractive to some insects.