OCCURRENCE AND DISTRIBUTION OF ASCOSPHAERA-APIS IN NORTH-AMERICA - CHALKBROOD IN FERAL HONEY-BEE COLONIES THAT HAD BEEN IN ISOLATION ON SANTA-CRUZ ISLAND, CALIFORNIA FOR OVER 110 YEARS

Twenty strains of Ascosphaera apis were cultured from larval mummies a nd discolored larvae from feral honey bee colonies that had been in is olation on Santa Cruz Island, California for over 110 years, long befo re chalkbrood was first reported from the USA in 1968. Disease symptom s and enzyme patterns of A apis differed from those found on the mainl and. island strains showed little variability. These results and the h istory of the bees suggest that the pathogen accompanied the bees to t he island and that the bees survived chalkbrood by a combination of hy gienic behavior and microorganisms that inhibit A apis which were isol ated from larvae and stored pollen.