S24: Biological and chemical control options for Geomyces destructans

Tuesday, October 30, 2012: 1:00 PM
Christopher T. Cornelison, Biology, Georgia State University, Atlanta, GA and Sidney A. Crow, Applied and Environmental Microbiology, Georgia State University, Atlanta, GA
The recently identified causative agent of White Nose Syndrome (WNS), Geomyces destructans, has been responsible for the mortality of 5.7 million North American bats since its emergence in 2006. In an effort to identify potential biological and chemical control options for WNS 6 previously described bacterially produced volatile organic compounds (VOCs) and  multiply induced Rhodococcus rhodochrous DAP96253 were screened for anti-Geomyces destructans activity. Geomyces destructans spores and mycelial plugs were exposed to the VOCs and induced Rhodococcus in a closed air space at 15°C and 4°C and evaluated for growth inhibition and inhibition of spore germination. All VOCs inhibited radial growth of mycelial plugs and growth from spores at both temperatures, with the greatest effect at low temperature (4°C). Induced Rhodococcus completely inhibited growth from spores at 15°C and had a strong fungistatic effect at 4°C. Subsequently, induced Rhodococcus inhibited Geomyces destructans growth from spores when cultured in a shared air space with bat tissue explants inoculated with Geomyces destructans spores. Additionally, in situ application methods for induced Rhodococcus such as fixed cell catalyst and fermentation cell paste in non-growth conditions were screened with promising results.  The identification of bacterially produced VOCs and inducible biological agents with anti-Geomyces destructans activity expands the pool of potential biological and chemical control options for WNS and provides wildlife management personnel with tools to combat this devastating disease.