title: Laboratory evaluation of Lagenidium giganteum (Oomycetes: Lagenidiales) in water from Contra Costa County, California, mosquito sources.
abstract: Six bioassays were performed to evaluate the efficacy of the fungus, Lagenidium giganteum, against mosquitoes in water collected from 75 sources. The fungus infected larvae of 4 genera and produced greater than 90% mortality in water from some of the creeks, artificial containers and the wild rice field tested during 4 of the assays. There was no larval mortality due to the fungus in water from irrigated pastures or marshes. Water quality parameters associated with L. giganteum infection varied among the bioassays; low measurements of total dissolved solids (TDS), hardness (CaCO3), conductivity, chemical oxygen demand (COD), ammonium nitrogen (NH3-N), phosphate (PO4) and salinity were significantly (P less than 0.05) correlated with fungal efficacy in one or more of the assays. Regression analyses selected TDS, CaCO3, COD, NH3-N and/or PO4 as the best predictors of larval mortality due to L. giganteum. Turbidity and pH were not correlated with fungal efficacy.
authors.affiliation: Contra Costa Mosquito Abatement District, Concord, CA 94520.
authors.forename: V I
authors.initials: VI
authors.lastname: Kramer
mesh_terms: D000818:Animals; D002140:California; D008411:Chytridiomycota; D009033:Culicidae / Q000382:microbiology*; D007814:Larva / Q000382:microbiology; D009868:Oomycetes; D010572:Pest Control, Biological