Larvicidal effect of Verticillium lecanii metabolites on Culex quinquefasciatus and Aedes aegypti larvae

Objective: To investigate the efficacy of Verticillium lecanii metabolites after filtration and\udpurification through the chromatographic techniques against the larvae of Culex quinquefasciatus\ud(Cx. quinquefasciatus) and Aedes aegypti (Ae. aegypti). Methods: This fungus was cultured on potato\uddextrose broth in the laboratory at 25 °C, while the relative humidity was maintained at (75暲5)% for 15 d.\udFiltration process of metabolites was done using whatman-1 filter paper, column chromatography and\udflash chromatography. Larvicidal efficacy was performed at six different concentrations with different\udeffective volume ratios (ethanol/metabolites: 9:1, 8:2, 7:3, 6:4, 5:5, 4:6, 3:7, 2:8 and 1:9) for a period of 24,\ud48 and 72 h, respectively. Results: Among all ratios, the 4:6 ratio was found effective against the larvae\udof Cx. quinquefasciatus and 1:9 ratio was found effective against the larvae of Ae. aegypti. The first,\udsecond, and third instars of Cx. quinquefasciatus were found more susceptible to the metabolites than\udthe fourth instars. However, the first instars of Ae. aegypti were found more susceptible than the other\udinstars. Conclusions: Larvicidal efficacy has been pioneered by us for the first time and performed\udagainst all instars of Cx. quinquefasciatus and Ae. aegypti. The filtration and purification made\udmetabolites more effective than the crude metabolites. The metabolites of Verticillium lecanii could be\udan environmentally safer larvicide source for the control of mosquito larvae