Production, virulence and tolerance to abiotic factors of microsclerotia from the fungal entomopathogen Metarhizium robertsii

Microsclerotia (MS) are resistance structures naturally produced by several phytopathogenic fungi and can be artificially induced in some entomopathogenic fungi using liquid fermentation with specific conditions. 

MS in entomopathogenic fungi are defined as dark pigmented and compact aggregates of hyphal threads with or without a distinct core. 

MS are considered the most promising fungal propagules to be used as active ingredient in mycoinsecticide due to their high resistance to stress conditions and capacity to germinate under suitable conditions, producing infective conidia. 

Objective: To select a culture medium for microsclerotia production and assess the MS tolerance to heat and ultraviolet radiation (UV-B) and the insecticide activity of MS-derived conidia against Diatraea saccharalis larvae in comparison with conidia produced by solid fermentation (SSF) on rice.

Spanish title: Producción, tolerancia a factores abióticos y potencial insecticida de microesclerocios producidos por Metarhizium robertsii