Adulticidal Activity of Metarhizium anisopliae s.l. (Hypocreales: Clavicipitaceae) Native Strains From Argentina Against Aedes aegypti (Diptera: Culicidae)

FALVO, MARIANEL L; MUSSO, ANAHI; ORDOQUI, ELIANA; LÓPEZ LASTRA, CLAUDIA C; LUZ, CHRISTIAN; GARCÍA, JUAN J

JOURNAL OF MEDICAL ENTOMOLOGY

ENTOMOLOGICAL SOC AMER

Año: 2020 vol. 57 p. 636 - 640

0022-2585

The adulticidal activity of six fungal strains of Metarhizium anisopliae (Metschn.) Sorokin s.l. (Hypocreales:Clavicipitaceae) against Aedes aegypti (L.) (Diptera: Culicidae) was assessed. These strains (CEP 085, CEP 087,CEP 120, CEP 350, CEP 404, and CEP 423) were isolated from soil samples or nondipteran hosts collectedfrom areas in Argentina where Ae. aegypti is distributed. Bioassays were performed with four conidial concentrations plus a control of each fungal strain to determine the lethal concentrations (LC50/LC90), the mediansurvival times (ST50), the mean percentage of the surviving individuals, and the mean percentage of mycotizedcadavers. The strains were able to infect and kill adult Ae. aegypti. Significant differences were found amongthe LC50 values, with CEP 423 as the most virulent strain with the lowest LC50 (2.4 × 106 conidia/ml). At 1 × 107conidia/ml: no significant differences were found in the Kaplan?Meier survival functions among the strains; theST50 ranged from 5 (CEP 085) to 8 d (CEP 350); and the mean percentage of the surviving adults was between13.3 (CEP 085, CEP 350 and CEP 423) and 46.7% (CEP 087). Significant differences were also found amongstrains in the mean percentage of cadavers with fungal sporulation. Strain CEP 423 produced the highestpercentage of mycotized adults (70%). The concentration of the inoculum significantly affected the survival ofindividuals and the percentage of mycotized cadavers within each strain. Metarhizium anisopliae s.l. CEP 423was selected as the most promising candidate for further research aiming to develop a mycoinsecticide against Ae. aegypti.