Title:Baktériumtörzs-gyűjtemény létrehozása a mézelő méhek (Apis mellifera) nyúlós (amerikai) költésrothadását okozó Paenibacillus larvae hazai reprezentatív izolátumaiból
SUMMARY Background: American foulbrood caused by P. larvae has great economic impact among the bacterial honey bee diseases. The causative agent and the notifiable disease occur worldwide, also in Hungary. P. larvae is a Gram-posi tive spore-forming bacterium species. The resistance of its spore is very high, accordingly it can survive for decades. American foulbrood is a disease of the bee brood and the infection may spread fast in the colony and between colo nies. Currently there is no effective treatment of the disease. Prevention from the clinical form of the disease might be aimed by the reduction of the number of spores in the bee hive. Using antibiotic treatment for honey bee colonies is forbidden in Hungary. The colonies showing clinical signs have to be killed, and the apiary gets quarantined. Objectives: Our purpose was to create a representative bacterial culture col lection of P. larvae in Hungary, in order to study the features of the Hungarian isolates (e.g. phenotypic and genotypic characters, susceptibility against disin fectants and so on). Materials and Methods: A total of 297 honey samples were collected from different parts of Hungary (19 counties, 143 settlements), and different cultural methods were used for the isolation of the causative agent. Based on the cul tural, morphological and biochemical features 82 isolates were cultured and stored in freezer at −80 °C till use. Identification of the isolates on species level was carried out using MALDI-TOF mass spectrometry, which identified all iso lates as P. larvae. Results and Discussion: As a result of our work on the one part the partici pating apiaries gained information about the infection of their colonies with the causative agent of American foulbrood, and on the other part a representative bacterial culture collection was set up, which comprise 82 P. larvae isolates from different parts of Hungary (17 counties, 49 settlements). This bacterial culture collection serves a basis for further research.