title: Exposure of Metarhizium acridum mycelium to light induces tolerance to UV-B radiation.
abstract: Metarhizium acridum is an entomopathogenic fungus commonly used as a bioinsecticide. The conidium is the fungal stage normally employed as field inoculum in biological control programs and must survive under field conditions such as high ultraviolet-B (UV-B) exposure. Light, which is an important stimulus for many fungi, has been shown to induce the production of M. robertsii conidia with increased stress tolerance. Here we show that a two-hour exposure to white or blue/UV-A light of fast-growing mycelium induces tolerance to subsequent UV-B irradiation. Red light, however, does not have the same effect. In addition, we established that this induction can take place with as little as 1 min of white-light exposure. This brief illumination scheme could be relevant in future studies of M. acridum photobiology and for the production of UV-B resistant mycelium used in mycelium-based formulations for biological control.
authors.affiliation: Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP 14040-903, Brazil.
authors.forename: Guilherme T P
authors.initials: GT
authors.lastname: Brancini
authors.affiliation: Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, GO, 74605-050, Brazil.
authors.forename: Drauzio E N
authors.initials: DE
authors.lastname: Rangel
authors.affiliation: Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP 14040-903, Brazil gbraga@fcfrp.usp.br.
authors.forename: Gilberto Ú L
authors.initials: GÚ
authors.lastname: Braga
mesh_terms: D008027:Light; D052981:Metarhizium / Q000528:radiation effects*; D050296:Microbial Viability / Q000528:radiation effects; D025282:Mycelium / Q000528:radiation effects*; D011836:Radiation Tolerance; D013312:Stress, Physiological; D014466:Ultraviolet Rays
keywords: Metarhizium; blue light; fungal photobiology; light; stress tolerance; ultraviolet radiation