38th Annual Meeting of the Society for Invertebrate Pathology

Ascosphaera spp. fungi are associated with social and solitary bees, in some cases as pathogens causing chalkbrood disease. As a supplement to morphological identification, we developed a simple PCR-based identification method for selected Ascosphaera species. We exploited sequence differences in the internal transcribed spacer regions of rDNA to design species-specific primers. Analysis involves simply scoring the presence or absence of a single band for a given pair of primers. The method can distinguish the four Ascosphaera species known to be associated with honeybees. It also distinguishes Ascosphaera aggregata, the chalkbrood pathogen of the alfalfa leafcutting bee, from other Ascosphaera species associated with this bee. We expect the method will be useful for identifying and determining purity of Ascosphaera cultures, and may be a first step toward development of an early detection method of chalkbrood infection in honeybees and leafcutting bees.