UV-B radiation reduces in vitro germination of Metarhizium anisopliae s.l. but does not affect virulence in fungus-treated Aedes aegypti adults

MARIANEL L. FALVO ; RONALDO A. PEREIRA-JUNIOR ; JUSCELINO RODRIGUES; CLAUDIA C.LÓPEZ LASTRA; GARCÍA JUAN JOSÉ ; FERNANDES KORP, EVERTON; LUZ; W. CHRISTIAN

JOURNAL OF APPLIED MICROBIOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2016

1364-5072

ABSTRACTControl of diurnal Aedes aegypti with mycoinsecticides should consider the exposure of fungus-treated adults to sunlight, and especially to UV-B radiation that might affect activity of conidia applied on the mosquito´s surface. In the present study, germination of M. anisopliae s.l. IP 46 conidia on SDAY medium was not affected at the lowest level of irradiation with UV-B, 0.69 kJ/m2, but was retarded and reduced at higher levels, 2.075 and 4.15 kJ/m2, and completely inhibited at ≥ 8.3 kJ/m2. In contrast, germination of conidia applied onto fiberglass nettings and exposed up to 16.6 kJ/m2 (or not exposed in the controls) did not differ significantly among doses and the controls. There was also no significant impact of UV-B on adulticidal activity of IP 46 for fungus-treated adults exposed up to 16.6 kJ/m2 on the subsequent conidiogenesis on cadavers. The Quaite weighted UV-B irradiance in the laboratory (1152 mW m?2 ) was higher than the irradiance observed in the city of Goiânia in Central Brazil on midday (706 mW m?2 in August to 911 mW m?2 in October 2015). Findings indicated that UV-B does not impair the activity of IP 46 conidia applied previously to irradiation on A. aegypti adults; nevertheless, fiberglass nettings treated with conidia should be protected from any extended exposure to sunlight