Pathogenicity of Fusarium oxysporum against the larvae of Culex quinquefasciatus (Say) and Anopheles stephensi (Liston) in laboratory

The entomopathogenic fungi Fusarium oxysporum are the next generation mosquito controlling agent. F. oxysporum basically contains unique toxin and can be a selectively good agent in tropical countries. We are reporting here the efficacy of the metabolites of F. oxysporum against the larvae of Anopheles stephensi and Culex quinquefasciatus in the laboratory. F. oxysporum was grown on Czapek Dox broth. The bioassays were run at five different concentrations (1.30, 1.60, 1.77, 1.90, and 2.00 ppm). The LC50, LC90, and LC99 values with 95% fiducial limits and probit equations were calculated by probit analysis. The mortality was observed after 24, 48, and 72 h against all instars. The LC90 values in the case of C. quinquefasciatus after 48 h when calculated were 1.85, 1.92, 1.87, and 1.87 ppm, respectively, while LC99 values calculated were 2.24, 2.25, 2.18, and 2.19 ppm. Moreover, after 48 h in the case of A. stephensi, the LC50 values for the first, second, third, and fourth instars were recorded as 1.48, 1.51, 1.71, and 1.50 ppm, respectively. The LC90 values recorded were 1.88, 1.91, 1.93, and 1.89 ppm and LC99 values observed were 2.36, 2.23, 2.26, and 2.21 ppm. The results obtained 24, 48, and 72 h have been compared and it was observed significantly that 48 h after exposure the metabolite has more pathogenicity. The results of the metabolites of F. oxysporum may be considered as a new bio-control agent for vector mosquitoes if the field trial succeeds.