LIPM and INP-ENSATBP27 31326 Castanet-Tolosan,France
Mini-biographyThierry Huguet is Director of Research at CNRS (Centre National de la Recherche Scientifique). His field of interest is the study of the natural variations existing within the model legume
Medicago truncatula in order to identify and clone genes and QTLs of agronomical interest. Current projects involve 1) the development of
M.truncatula collections based on well-identified natural populations. 2) the creation of dedicated recombinant populations and genetic maps anchored in the
M.truncatula physical map. 3) the study of the genetic basis of abiotic and biotic stress resistance in
M.truncatula. More information is available on
Thierry Huguet's home page.
Identifying genes underlying QTLs responsible for M. truncatula natural variations in abiotic stress responses using a Consensus Genetic-Physical Map (CGPM)Thierry Huguet
1,2, Carine Ameline-Torregrosa
2, Michèle Ghérardi
2, Fabien Chardon
2,3, Fatma Lazrek
2, Elodie Sartorel
2, Mounawer Badri
4, Martin Crespi
5, Mohamed Elarbi Aouani
41 Laboratoire Symbiose et Pathologie des Plantes (SP2), Pôle de Biotechnologie Végétale, INP-ENSAT, Avenue de l'Agrobiopôle BP 32607 Auzeville, 31326 Castanet Tolosan, France. thierry.huguet@ensat.fr
2 Laboratoire Interactions Plantes-Microorganismes (LIPM), CNRS-INRA, BP27, 31326 Castanet - Tolosan Cedex, France.
3 Unité de la Nutrition Azotée des Plantes, INRA, Route de St Cyr, 78026 Versailles, France.
4 Laboratoire Interactions Légumineuses Microorganismes, Centre de Biotechnologie, Technopole de Borj Cédria (CBBC), BP901, Hammam-Lif, 2050, Tunisia.
5 Institut des Sciences du Végétal, C.N.R.S., F-91198 Gif-sur-Yvette, France.
Drought and salt stresses are a major constraint to crop productivity. However, the mechanisms developed by legumes in response to these environmental stresses remain largely unknown. Phenotypic variations occurring among natural populations provide an unlimited source of genetic diversity. Nevertheless, the identification of genes involved in these natural variations requires the development of specific tools (RILs populations and dedicated genetic maps).
From a selection of
Medicago truncatula lines growing in various eco-environmental conditions, a set of Recombinant Inbred Lines (RILs) were produced. A Consensus Genetic-Physical Map (CGPM) was created for several RILs derived from a common parental line (Jemalong A17) comprising about 60 loci almost evenly distributed. Each locus corresponds to a BAC, which contains different markers that are polymorphic for at least one RILs population. Consequently, these CGPM maps are anchored into the
M. truncatula physical map and rely all RILs populations.
Among the genotypes screened, three lines (Jemalong A17, F83005.5 and TN1.11) showed contrasted tolerance to salinity and drought and were selected for further genetic and genomic studies. A number of genetic determinants (QTLs) involved in tolerance to salt and drought stresses have been identified using LR5 RILs population (Jemalong A17 x F83005.5). A strategy, based on the co-localization of the identified QTLs with some candidate genes identified by transcriptomic approaches, will be exposed and the results discussed.
This work is supported in part by French-Tunisian cooperation (CMCU 00F0909 , PICS 712) and by European Union (FP6 Integrated Project “Grain Legumes”). FC, ES and CAT are supported by a grant from the FP6 Integrated Project “Grain Legumes”.
