Ground and aerial application of the sexual and asexual stages of Lagenidium giganteum (Oomycetes: Lagenidiales) for mosquito control.

Fermentor-grown cultures of the sexual and asexual stages of Lagenidium giganteum were applied in rice fields in the Central Valley near Sacramento, CA. Both ground and aerial applications of the asexual stage resulted in high levels of immediate control of sentinel Culex tarsalis and indigenous Cx. tarsalis and Anopheles freeborni larvae and provided some degree of control throughout the four-month mosquito breeding season. Oospores which were desiccated in the field following application provided consistently high larval infection levels after reflooding of the fields. Advantages of using the sexual stage of L. giganteum for field larval control are presented.