title: Ecotoxicological Impact of the Bioherbicide Leptospermone on the Microbial Community of Two Arable Soils.
abstract: The ecotoxicological impact of leptospermone, a β-triketone bioherbicide, on the bacterial community of two arable soils was investigated. Soil microcosms were exposed to 0 × (control), 1 × or 10 × recommended dose of leptospermone. The β-triketone was moderately adsorbed to both soils (i.e.,: K fa ~ 1.2 and K oc ~ 140 mL g(-1)). Its dissipation was lower in sterilized than in unsterilized soils suggesting that it was mainly influenced by biotic factors. Within 45 days, leptospermone disappeared almost entirely from one of the two soils (i.e., DT50 < 10 days), while 25% remained in the other. The composition of the microbial community assessed by qPCR targeting 11 microbial groups was found to be significantly modified in soil microcosms exposed to leptospermone. Pyrosequencing of 16S rRNA gene amplicons showed a shift in the bacterial community structure and a significant impact of leptospermone on the diversity of the soil bacterial community. Changes in the composition, and in the α- and β-diversity of microbial community were transient in the soil able to fully dissipate the leptospermone, but were persistent in the soil where β-triketone remained. To conclude the bacterial community of the two soils was sensitive to leptospermone and its resilience was observed only when leptospermone was fully dissipated.
authors.affiliation: Biocapteurs Analyse Environnement, EA 4218, University of Perpignan via DomitiaPerpignan, France; Centre de Recherches Insulaires et Observatoire de l'Environnement, USR 3278 EPHE-Centre National de la Recherche Scientifique, University of Perpignan via DomitiaPerpignan, France; Institut National de la Recherche Agronomique, UMR 1347 Agroécologie, EcolDurDijon, France.
authors.forename: Sana
authors.initials: S
authors.lastname: Romdhane
authors.affiliation: Institut National de la Recherche Agronomique, UMR 1347 Agroécologie, EcolDur Dijon, France.
authors.forename: Marion
authors.initials: M
authors.lastname: Devers-Lamrani
authors.affiliation: Biocapteurs Analyse Environnement, EA 4218, University of Perpignan via Domitia Perpignan, France.
authors.forename: Lise
authors.initials: L
authors.lastname: Barthelmebs
authors.affiliation: Biocapteurs Analyse Environnement, EA 4218, University of Perpignan via Domitia Perpignan, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Calvayrac
authors.affiliation: Centre de Recherches Insulaires et Observatoire de l'Environnement, USR 3278 EPHE-Centre National de la Recherche Scientifique, University of Perpignan via Domitia Perpignan, France.
authors.forename: Cédric
authors.initials: C
authors.lastname: Bertrand
authors.affiliation: Centre de Recherches Insulaires et Observatoire de l'Environnement, USR 3278 EPHE-Centre National de la Recherche Scientifique, University of Perpignan via Domitia Perpignan, France.
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Cooper
authors.affiliation: Bioagricultural Sciences and Pest Management Department, Colorado State University Fort Collins, CO, USA.
authors.forename: Franck E
authors.initials: FE
authors.lastname: Dayan
authors.affiliation: Institut National de la Recherche Agronomique, UMR 1347 Agroécologie, EcolDur Dijon, France.
authors.forename: Fabrice
authors.initials: F
authors.lastname: Martin-Laurent
keywords: bacterial community; biodegradation; bioherbicide; leptospermone; microbial ecotoxicology