Paenibacillus larvae INHIBITION, ETHIOLOGICAL AGENT OF AMERICAN FOULBROOD IN HONEY BEE, BY DIFFERENT EXTRACTS FROM FLUORENSIA SPP.

REYES, G.; TORRES M.J.; MAGGI, M.; MARIOLI, J. M.; SOSA, V. E.; URIBURU, M. L.; AUDISIO, M.C.

San Miguel de Tucumán

Jornada; XXIX Jornadas Científicas Asociación de Biología de Tucumán; 2013

Asociación de Biología de Tucumán

Paenibacillus larvae is the ethiological agent of American foulbrood in Apis mellifera L. The aim of the present work was to investigate the antagonistic activity of three species of genus Fluorensia, against P. larvae. The hexane, chloroform (CE) and ethyl ether (EEE) extracts from aerial parts of Flourensia riparia, F. fiebrigii and F. tortuosa were obtained. Inhibitory activity was evaluated against three different strains of P. larvae using the disk diffusion method in agar MPYGP. The most active extracts toxicity on bees was evaluated according to the complete exposure technique.The analysis revealed that all different tested Flurorensia extracts inhibited the insect growth; however, non-polar extracts had no significant inhibitory effect. The magnitude of the antagonistic effect was chemical nature of extract and strain of P. larvae dependent. The CE and EEE extracts from F. riparia and EEE from F. fiebrigii were the most active against P. larvae Azul, the most sensitive indicator strain (MIC values 283 ppm, 1932 ppm and 2481 ppm).Toxicity tests have shown that no lethal effects on exposed bees were observed. These results constitute a viable alternative to apply these extracts on infected P. larvae hives.