Typing of Pantoea agglomerans isolated from colonies of honey bees (Apis mellifera) and culturability of selected strains from honeyIgor Loncaric1, 2, 3, Helmut Heigl2, Elisabeth Licek3, Rudolf Moosbeckhofer2, Hans-Jürgen Busse1 and Renate Rosengarten1
1 Institute of Bacteriology, Mycology and Hygiene, University of Veterinary Medicine, Veterinaerplatz 1, 1210 Vienna, Austria
2 Institute for Apiculture, Austrian Agency for Health and Food Safety (AGES), Spargelfeldstrasse 191, 1226 Vienna, Austria
3 Clinic for Avian, Reptile and Fish Medicine, University of Veterinary Medicine, Veterinaerplatz 1, 1210 Vienna, Austria
Received 6 December 2007 – Revised 15 September 2008 – Accepted 1 October 2008 - Published online 22 January 2009
Abstract - Pantoea agglomerans is a possible biocontrol agent against fire blight (Erwinia amylovora) and a facultative pathogen of humans. Isolates were gathered from flowers, pollen loads, honey sacs, and freshly stored nectar (FSN). Under artificial inoculation conditions, strains completely lost their culturability at 24 °C after 120 h of incubation in honey and 156 h in honey solution, respectively. None of tested strains could be cultivated from FSN, honey, or honey solution after 48 h at temperatures higher then 28 °C. At different time intervals, culturable population levels at 35 °C and 24 °C were significantly higher in blossom honey or its solution than in blossom and honeydew honey or its solution. Our results indicated that P. agglomerans is widely spread throughout honey bee's environment. Strains lost culturability after short periods of incubation in honey or honey solution. In samples of honey and royal jelly from test colonies, no culturable P. agglomerans isolates could be detected.
Key words: bacterial diversity / strain traceability / pollen analysis / genomic fingerprinting / Erwinia amylovora
© INRA, DIB-AGIB, EDP Sciences 2009