title: Chytrid mycoparasitism of entomophthoralean azygospores.
abstract: Mycoparasitism - when one fungus parasitizes another - has been reported to affect Beauveria bassiana and mycorrhizal fungi in the field. However, mycoparasitism of any fungi in the Order Entomophthorales has never been reported before now. The majority of entomophthoralean species persist as resting spores (either zygospores or azygospores) in the environment and dormant entomophthoralean resting spores (whether formed as zygospores or azygospores) are thought to be especially well adapted for survival over long periods due to their thick double walls. Entomophthoralean resting spores can accumulate in the soil as large reservoirs of inoculum which can facilitate the onset and development of epizootics. We report parasitism of azygospores of the gypsy moth pathogen Entomophaga maimaiga caged in soil from southern Ohio by the chytrid fungus Gaertneriomyces semiglobifer. G. semiglobifer had previously been isolated from soil samples from North America, Europe and Australia or horse manure from Virginia. After isolation and identification of G. semiglobifer, azygospores of E. maimaiga exposed to zoospores of G. semiglobifer exhibited high levels of mycoparasitism and G. semiglobifer was subsequently reisolated from mycoparasitized resting spores. We discuss the importance of this finding to the epizootiology of insect diseases caused by entomophthoralean fungi.
authors.affiliation: Department of Entomology, Cornell University, Ithaca, NY 14853-2601, USA. Electronic address: aeh4@cornell.edu.
authors.forename: Ann E
authors.initials: AE
authors.lastname: Hajek
authors.forename: Joyce E
authors.initials: JE
authors.lastname: Longcore
authors.forename: D
authors.initials: D
authors.lastname: Rabern Simmons
authors.forename: Kenlyn
authors.initials: K
authors.lastname: Peters
authors.forename: Richard A
authors.initials: RA
authors.lastname: Humber
mesh_terms: D008411:Chytridiomycota / Q000145:classification / Q000302:isolation & purification / Q000502:physiology*; D020091:Entomophthorales / Q000302:isolation & purification / Q000502:physiology*; D006790:Host-Parasite Interactions; D013172:Spores, Fungal / Q000502:physiology
keywords: Azygospores; Biological control; Chytridiomycota; Entomophaga maimaiga; Gaerntneriomyces semiglobifer; Gypsy moth