ABSTRACT
Aspergillus spp. (primarily A. niger and secondarily A. flavus), Penicillium spp., Cladosporium spp., and Rhizopus spp. are the main fungi regularly found in bee bread. They function as a natural defense against the pathogenic fungal diseases chalkbrood and stonebrood, as inferred by in vitro fungal-fungal interaction bioassays. Ten other species are also present in bee bread, but as minor though necessary components for maintaining the proper balance of the bee bread mycoflora. Colonies in orchards that were sprayed with fungicides had low amounts of bee bread fungi. Agents known to suppress growth or kill bee bread fungi are fungicides, formic acid, oxalic acid miticides, and high fructose corn syrup. Communication between growers and beekeepers is encouraged to assess the timing of direct and nearby fungicide applications so that colonies could be moved if necessary.
