EVALUATION OF LAGENIDIUM-GIGANTEUM FOR BIOCONTROL OF MANSONIA MOSQUITOS IN FLORIDA (DIPTERA, CULICIDAE)

Inoculative releases of Lagenidium giganteum (California isolate) were made against a population of Mansonia dyari during a typical breeding season at one site in eastern Hillsborough County, Florida. Zoospores of L. giganteum were introduced into outdoor caged replicated test po ols containing waterlettuce, Pistia stratiotes, and larvae of M. dyari collected from an inactive phosphate pit. First and second instar lar vae were added twice a week between August and December, 1993, to simu late natural oviposition by ill. dyari. Adult emergence was reduced by >77% in test pools treated with L. giganteum. Sentinel larvae provide d evidence of recycling of the fungus approximately 14 days posttreatm ent. Continuous larval mortality of ill. dyari was observed for a peri od of 46 days. Our data showed that water quality in the test pools an d phosphate pit was suitable for fungal growth and zoosporogenesis as long as the water temperature did not exceed 38 degrees C. (C)1997 Aca demic Press.