RESEARCH ARTICLE Changes in mesophyll element distribution and phytometabolite contents involved in fluoride tolerance of the arid gypsum-tolerant plant species Atractylis serratuloides Sieber ex Cass. (Asteraceae) Asma Boukhris & Isabelle Laffont-Schwob & Jacques Rabier & Marie-Dominique Salducci & Lefi El Kadri & Alain Tonetto & Thierry Tatoni & Mohamed Chaieb Received: 28 September 2014 /Accepted: 4 December 2014 # Springer-Verlag Berlin Heidelberg 2014 Abstract Atractylis serratuloides is an abundant native spiny species that grows in the surroundings of superphosphate factories in Tunisia. This plant species is adapted to arid environments and tolerates a high level of fluoride pollution in soils. The aim of this study was to better understand the physiological mechanisms of fluoride tolerance of this spe- cies, comparing the fluoride-contaminated sites of Gabes and Skhira with the reference site of Smara. Results demonstrated the involvement of leaf element and phytometabolite balances in the in situ response of A. serrulatoides to fluoride. Calcium, sulphur and magnesium were differently distributed between the sites of Gabes and Smara in all plant organs. No specific tissue fluorine accumulation in root, stem and leaf, even in the most contaminated site at Gabes, was detected by EDAX mapping. Lower anthocyan and flavonol levels but enhanced nitrogen balance index were found in A. serrulatoides leaves from Gabes compared to the two other sites. A. serratuloides appeared as a fluoride excluder and its tolerance involved calcium interactions with fluoride. Moreover, an occurrence of dark septate endophytes and arbuscular mycorhizal fungi in root systems of A. serratuloides was reported for the first time, and these symbioses were present but low at all sites. We suggest the use of this plant species for fluoride-polluted soil stabilization. Keywords Arbuscular mycorrhizae . Cation balance . Dark septate endophytes . EDAX . Fluorine . Plant tolerance Introduction It has been well documented that industrial activities such as phosphate fertilizer production are causing increasing fluoride pollution in the environment (Rouis and Bensalah 1990; Rutherford et al. 1994; Weinstein and Davison 2004). It has been generally observed that in plant species growing in the vicinity of a source of atmospheric fluoride, foliar fluoride concentrations will be dominated by direct uptake from the air and the contribution from the soil will be minimal (Braen and Weinstein 1985), except for very acidic soils where fluoride uptake from soil may play a major role (Treshow and Ander- son 1989). Plant fluorine uptake from areas receiving fluorine inputs has attracted increasing attention due to the risk of plant fluorine accumulation and further transfer to the higher trophic Responsible editor: Philippe Garrigues A. Boukhris : I. Laffont-Schwob (*) : J. Rabier : M.<D. Salducci : T. Tatoni Institut Méditerranéen de Biodiversité et d’Ecologie Marine et Continentale (IMBE), Aix Marseille Université, CNRS, IRD, Avignon Université, 52 Avenue Normandie-Niemen, 13397 Marseille CEDEX 20, France e-mail: isabelle.laffont-schwob@imbe.fr A. Boukhris e-mail: asmaboukhris@ymail.com J. Rabier e-mail: jacques.rabier@imbe.fr T. Tatoni e-mail: thierry.tatoni@imbe.fr A. Boukhris : L. El Kadri : M. Chaieb Plant Diversity and Ecosystems in Dry Environment, Faculty of Science, University of Sfax, 3000 Sfax, Tunisia L. El Kadri e-mail: elkadrilefi@yahoo.fr M. Chaieb e-mail: mohamed.chaieb@gnet.tn A. Tonetto Fédération de Chimie de Marseille FR 1739 Service PRATIM, Aix Marseille Université, 3 Place Victor Hugo, 13331 Marseille CEDEX 3, France e-mail: alain.tonetto@univ-amu.fr Environ Sci Pollut Res DOI 10.1007/s11356-014-3957-6