title: Lichen microalgae are sensitive to environmental concentrations of atrazine.
abstract: The identification of new organisms for environmental toxicology bioassays is currently a priority, since these tools are strongly limited by the ecological relevance of taxa used to study global change. Lichens are sensitive bioindicators of air quality and their microalgae are an untapped source for new low-cost miniaturized bioassays with ecological importance. In order to increase the availability of a wider range of taxa for bioassays, the sensitivity of two symbiotic lichen microalgae, Asterochloris erici and Trebouxia sp. TR9, to atrazine was evaluated. To achieve this goal, axenic cultures of these phycobionts in suspension were exposed to a range of environmental concentrations of the herbicide atrazine, a common water pollutant. Optical density and chlorophyll autofluorescence were used as endpoints of ecotoxicity and ecophysiology on cell suspensions. Results show that lichen microalgae show high sensitivity to very low doses of atrazine, being higher in Asterochloris erici than in Trebouxia sp. TR9. We conclude that environmental concentrations of atrazine could modify population dynamics probably through a shift in reproduction strategies of these organisms. This seminal work is a breakthrough in the use of lichen microalgae in the assessment of micropollution effects on biodiversity.
authors.affiliation: a Biology and Geology Department, ESCET , Rey Juan Carlos University , Móstoles (Madrid) , Spain.
authors.forename: Helena Moreno
authors.initials: HM
authors.lastname: Traba
authors.affiliation: a Biology and Geology Department, ESCET , Rey Juan Carlos University , Móstoles (Madrid) , Spain.
authors.forename: Noelia
authors.initials: N
authors.lastname: Domínguez-Morueco
authors.affiliation: b Departamento de Botánica , Universitat de València, ICBIBE, Fac. C. Biológicas , Burjassot (Valencia) , Spain.
authors.forename: Eva
authors.initials: E
authors.lastname: Barreno
authors.affiliation: a Biology and Geology Department, ESCET , Rey Juan Carlos University , Móstoles (Madrid) , Spain.
authors.forename: Myriam
authors.initials: M
authors.lastname: Catalá
mesh_terms: D001280:Atrazine / Q000008:administration & dosage / Q000633:toxicity*; D002734:Chlorophyll / Q000032:analysis / Q000378:metabolism; D000460:Chlorophyta / Q000187:drug effects* / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D054750:Ecotoxicology / Q000379:methods*; D008011:Lichens / Q000187:drug effects* / Q000502:physiology; D058086:Microalgae / Q000187:drug effects* / Q000378:metabolism; D013559:Symbiosis; D014874:Water Pollutants, Chemical / Q000008:administration & dosage / Q000633:toxicity
chemical_list: D014874:Water Pollutants, Chemical; D002734:Chlorophyll; D001280:Atrazine
keywords: Asterochloris erici; Trebouxia; bioassay; ecotoxicology; low dose