Submitted to: Genbank
Publication Type: Other
Publication Acceptance Date: May 20, 2009
Publication Date: May 20, 2009
Citation: Bon, M., Guermache, F., Mercadier, G., Meikle, W. 2009. Screening for bacterial contaminants in a Beauveria bassiana-based biopesticide against varroa mites. Genbank.
In a collaborative effort to develop a biopesticide against varroa, strains of entomopathogenic fungus, a Beauveria bassiana isolate was isolated from varroa mites found in beehives in France and tested in bioassays at the European Biological Control Laboratory. This isolate was shown to be virulent against the mites in lab bioassays and to significantly increase mite fall in a series of field experiments (Meikle et al., 2006; 2007). For a field trial with 4 applications of the biopesticide, the B. bassiana 05002 conidia were supplied commercially. Unfortunately, the biopesticide was subsequently found to be contaminated with bacteria and hence this microbial contamination adversely affected field results. Two bacterial isolates were at the origin of the contamination. Both were identified as Pseudomonas using sequencing of the 16S ribosomal gene, partial sequences (Genbank accession numbers FJ948082 and FJ 948083) and ascertained as bacteria of the Pseudomonas fluorescens group using sequencing of the RNA polymerase beta subunit (rpo) gene, partial sequences (Genbank accession numbers FJ948084 and FJ 948085).