Métodos de preserva？？o de Acidovorax avenae subsp. citrulli

the phytopathogenic bacteria acidovorax avenae subsp. citrulli (aac), agent of bacterial blotch, causes severe damages to melon and other cucurbits in brazil and worlwide. the methods desiccation in filter paper, periodic transfer, sterile water and dried leaves were tested for preserving the strains aac1 and aac1.12 of this bacterium during 180 days. evaluations of bacterial viability were performed monthly by growing strains on culture media. the pathogenicity of viable cultures was evaluated by disease incidence and severity on melon seedlings. the desiccation in filter paper maintained 100% viability of the strains during the period while using the other methods, viability was lost during evaluations. desiccation in filter paper and periodic transfer were more efficient than sterile water and dried leaves in maintening strain pathogenicity during the time evaluated 180 days.