title: Isolation of culturable mycobiota from agricultural soils and determination of tolerance to glyphosate of nontoxigenic Aspergillus section Flavi strains.
abstract: Glyphosate-based herbicides are extensively used in Argentina's agricultural system to control undesirable weeds. This study was conducted to evaluate the culturable mycobiota [colony forming units (CFU) g(-1) and frequency of fungal genera or species] from an agricultural field exposed to pesticides. In addition, we evaluated the tolerance of A. oryzae and nontoxigenic A. flavus strains to high concentrations (100 to 500 mM - 17,000 to 84,500 ppm) of a glyphosate commercial formulation. The analysis of the mycobiota showed that the frequency of the main fungal genera varied according to the analyzed sampling period. Aspergillus spp. or Aspergillus section Flavi strains were isolated from 20 to 100% of the soil samples. Sterilia spp. were also observed throughout the sampling (50 to 100%). Aspergillus section Flavi tolerance assays showed that all of the tested strains were able to develop at the highest glyphosate concentration tested regardless of the water availability conditions. In general, significant reductions in growth rates were observed with increasing concentrations of the herbicide. However, a complete inhibition of fungal growth was not observed with the concentrations assayed. This study contributes to the knowledge of culturable mycobiota from agricultural soils exposed to pesticides and provides evidence on the effective growth ability of A. oryzae and nontoxigenic A. flavus strains exposed to high glyphosate concentrations in vitro.
authors.affiliation: a Microbiology and Immunology Department, Faculty of Exact, Physiochemical and Natural Science, National University of Río Cuarto , Río Cuarto, Córdoba , Argentina.
authors.forename: Cecilia S
authors.initials: CS
authors.lastname: Carranza
authors.affiliation: a Microbiology and Immunology Department, Faculty of Exact, Physiochemical and Natural Science, National University of Río Cuarto , Río Cuarto, Córdoba , Argentina.
authors.forename: Carla L
authors.initials: CL
authors.lastname: Barberis
authors.affiliation: b Chemistry Department, Faculty of Exact , Physiochemical and Natural Science, National University of Río Cuarto , Río Cuarto , Córdoba , Argentina.
authors.forename: Stella M
authors.initials: SM
authors.lastname: Chiacchiera
authors.affiliation: a Microbiology and Immunology Department, Faculty of Exact, Physiochemical and Natural Science, National University of Río Cuarto , Río Cuarto, Córdoba , Argentina.
authors.forename: Ana María
authors.initials: AM
authors.lastname: Dalcero
authors.affiliation: a Microbiology and Immunology Department, Faculty of Exact, Physiochemical and Natural Science, National University of Río Cuarto , Río Cuarto, Córdoba , Argentina.
authors.forename: Carina E
authors.initials: CE
authors.lastname: Magnoli
mesh_terms: D001118:Argentina; D001231:Aspergillus flavus / Q000187:drug effects*; D005658:Fungi / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D005998:Glycine / Q000031:analogs & derivatives* / Q000494:pharmacology; D006540:Herbicides / Q000494:pharmacology*; D012988:Soil Microbiology; D013025:Glycine max / Q000254:growth & development; D003313:Zea mays / Q000254:growth & development; D000097797:Glyphosate
chemical_list: D005998:Glycine; D006540:Herbicides; D000097797:Glyphosate
keywords: Culturable mycobiota; agricultural field; tolerance to glyphosate