@Article{Michalet_etal2013,
author="Michalet, S.
and Rohr, J.
and Warshan, D.
and Bardon, C.
and Roggy, J.-C.
and Domenach, A.-M.
and Czarnes, S.
and Pommier, T.
and Combourieu, B.
and Guillaumaud, N.
and Bellvert, F.
and Comte, G.
and Poly, F.",
title="Phytochemical analysis of mature tree root exudates in situ and their role in shaping soil microbial communities in relation to tree N-acquisition strategy",
journal="Plant Physiology and Biochemistry",
year="2013",
volume="72",
pages="169--177",
optkeywords="Chemical ecology",
optkeywords="Denitrification",
optkeywords="Eperua falcata",
optkeywords="Metabolic profiling",
optkeywords="Mycorrhizae",
optkeywords="Plant-microbes interactions",
optkeywords="Root exudates",
abstract="Eperua falcata (Aublet), a late-successional species in tropical rainforest and one of the most abundant tree in French Guiana, has developed an original strategy concerning N-acquisition by largely preferring nitrate, rather than ammonium (H. Schimann, S. Ponton, S. H{\"a}ttenschwiler, B. Ferry, R. Lensi, A.M. Domenach, J.C. Roggy, Differing nitrogen use strategies of two tropical rainforest tree species in French Guiana: evidence from 15N natural abundance and microbial activities, Soil Biol. Biochem. 40 (2008) 487-494). Given the preference of this species for nitrate, we hypothesized that root exudates would promote nitrate availability by (a) enhancing nitrate production by stimulating ammonium oxidation or (b) minimizing nitrate losses by inhibiting denitrification.Root exudates were collected in situ in monospecific planted plots. The phytochemical analysis of these exudates and of several of their corresponding root extracts was achieved using UHPLC/DAD/ESI-QTOF and allowed the identification of diverse secondary metabolites belonging to the flavonoid family.Our results show that (i) the distinct exudation patterns observed are related to distinct root morphologies, and this was associated with a shift in the root flavonoid content, (ii) a root extract representative of the diverse compounds detected in roots showed a significant and selective metabolic inhibition of isolated denitrifiers invitro, and (iii) in soil plots the abundance of nirK-type denitrifiers was negatively affected in rhizosphere soil compared to bulk. Altogether this led us to formulate hypothesis concerning the ecological role of the identified compounds in relation to N-acquisition strategy of this species. {\textcopyright} 2013 Elsevier Masson SAS.",
optnote="Export Date: 15 November 2013; Source: Scopus; Coden: Ppbie; doi: 10.1016/j.plaphy.2013.05.003; Language of Original Document: English; Correspondence Address: Michalet, S.; Universit{\'e} Lyon1, CNRS, UMR5557, INRA, USC1364, Ecologie Microbienne, Centre d{\textquoteright}Etude des Substances Naturelles, Pavillon N{\'e}tien, ISPB, 8 Avenue Rockefeller, 69373 Lyon cedex, France; email: sergemichalet@yahoo.fr",
optnote="exported from refbase (http://php.ecofog.gf/refbase/show.php?record=509), last updated on Fri, 15 Nov 2013 16:26:58 -0300",
issn="09819428 (Issn)",
opturl="http://www.scopus.com/inward/record.url?eid=2-s2.0-84886588890&partnerID=40&md5=45b36e0db3c99084ff85cbcd58c5c852"
}