title: Mass harvesting of the entomopathogenic fungus, Neozygites fresenii, from natural field epizootics in the cotton aphid, Aphis gossypii.
abstract: Epizootics caused by insect pathogens sometimes occur over wide areas and result in millions of infected insects. Naturally infected insects can be considered a natural resource for harvesting insect pathogens. We developed methods to mass harvest the fungal pathogen Neozygites fresenii (Entomophthorales: Neozygitaceae) from epizootics in Aphis gossypii (Homoptera: Aphididae) in a commercial cotton field in Arkansas. A total of 30,722 aphids infected with N. fresenii in the mature hyphal body or early conidiophore stages were harvested, dried, and frozen. Three desiccants were compared: silica gel, dry rock salt, and wet rock salt. Silica gel was the superior material because it more rapidly and thoroughly dried cotton leaves and aphids. Using this method a mean of 193.4 infected aphids could be harvested per hour from cotton leaves dried over silica gel. The quality of harvested infected aphids was high and resulted in a mean of 70.4% sporulation from infected aphids harvested from the silica gel desiccant.
authors.affiliation: Department of Entomology, University of Arkansas, 319 AGRI, Fayetteville, AR 72701, USA. steinkr@uark.edu
authors.forename: Donald C
authors.initials: DC
authors.lastname: Steinkraus
authors.forename: Gabriele O
authors.initials: GO
authors.lastname: Boys
mesh_terms: D000818:Animals; D001042:Aphids / Q000469:parasitology*; D003890:Desiccation / Q000379:methods; D020091:Entomophthorales / Q000302:isolation & purification*; D009172:Mycology / Q000379:methods*; D012492:Salts; D058428:Silica Gel; D012822:Silicon Dioxide; D020096:Zygomycosis / Q000469:parasitology*
chemical_list: D012492:Salts; D058428:Silica Gel; D012822:Silicon Dioxide