Programme<\/p>\n
<\/p>\n
9h30-9h45\u00a0: intro Pierre Capy<\/p>\n
9h45-10h30\u00a0: Christian Parisod Retrotransposons support reproductive isolation<\/p>\n
10h30- 10h45\u00a0: P. Le Gall Bilan et futur des \u00e9coles de terrain en Afrique Centrale<\/p>\n
10h45-11h\u00a0: A. B\u00e9cheler Mod\u00e8le d’inf\u00e9rence en d\u00e9mog\u00e9n\u00e9tique environnementale<\/p>\n
11h-11h20\u00a0: Pause<\/p>\n
Session Diversit\u00e9 et socio\u00e9cosyst\u00e8mes<\/p>\n
11h20-11h35\u00a0: R\u00e9mi Perrone Etude des relations entre diversit\u00e9 g\u00e9n\u00e9tique du bl\u00e9 tendre et profils de successions culturales en France entre 1980 et 2006<\/p>\n
11h35-11h50\u00a0: Abdel Kader Naino Jika Evolution of pearl millet diversity driven by farmer’s practices: a multi-level assessment<\/p>\n
11h50-12h05: Marie Vaugoyeau Urbanisation has variable influences on the breeding phenology of four passerine birds across Europe and North Africa<\/p>\n
12h05-12h20: Elodie Marchadie Decoding the genetic architecture of growth and water stress response in Arabidopsis thaliana<\/em>.<\/p>\n 12h20 -12h35\u00a0: St\u00e9phane Dupas R\u00e9ductionisme ou holisme; disiciplinaire ou transdisicplinaire\u00a0: Une lecture thermodynamique de recherches multi\u00e9chelles men\u00e9es \u00e0 l’IDEEV.<\/p>\n 12h35-14h15\u00a0: D\u00e9jeuner\/posters<\/p>\n Session Phylog\u00e9nomique et m\u00e9tag\u00e9nomique<\/p>\n 14h15-14h30\u00a0: Sylvie R\u00e9taux Evolution of the olfactory system in blind cavefish<\/p>\n 14h30-14h45: Stefan Little Integrating transcriptomes into the comparative floral evolution of magnoliids<\/p>\n 14h45-15h: Elisabeth Reyes Floral symmetry shifted 204 times in angiosperms<\/p>\n 15h-15h15: Rafael Isaac Ponce Toledo Phylogenomics traces the ancestor of primary plastids back to an early branching cyanobacterium<\/p>\n 15h15-15h30: Ludwig Jardillier Small freshwater ecosystems harbour complex protist communities characterised by seasonal dynamics and resilience<\/p>\n 15h30-15h45: Nicolas Pollet Phylogenetic and metabolic profiles of an amphibian gut microbiome<\/p>\n 15h45-16h05: Pause<\/p>\n Session: De la g\u00e9nomique structurale \u00e0 l\u2019\u00e9cophysiologie<\/p>\n 16h05-16h20: Aur\u00e9lie Hua-Van VHICA: A new method to discriminate between vertical and horizontal transposon transfer: application to the mariner family within Drosophila<\/p>\n 16h20-16h35: Johan Joets Structural and functional specificities of the genome of the European maize line FV2.<\/p>\n 16h35-16h50: Ariane Gratias-Weill Does pathogen infection have an impact of meiotic recombination in plants?<\/p>\n 16h50-17h05: Vanesa Sanchez Genomics and Diversity of Ni hyperaccumulation in plants<\/p>\n 17h05-17h20: Fr\u00e9d\u00e9ric Marion-Poll Des substances am\u00e8res pour prot\u00e9ger les plantes?<\/p>\n 17h20-17h40\u00a0: Pause<\/p>\n 17h40-18h25\u00a0: Lars Chittka Spatial memory in the economy of nature: bees as a model<\/p>\n <\/p>\n Christian Parisod<\/strong><\/p>\n christian.parisod@unine.ch<\/a><\/p>\n Evolutionary Botany 11 rue Emile-Argand CH-2000 Neuch\u00e2tel<\/p>\n Retrotransposons support reproductive isolation<\/p>\n Interspecific hybridization leads to new interactions among divergent genomes, revealing the nature of genetic incompatibilities having accumulated after the origin of species. Conflicts associated with misregulation of transposable elements in hybrids expectedly results in their activation and genome-wide changes that may be a key issue to species boundaries. Here, experimental reciprocal F1 hybrids between three wild wheat (Aegilops) species were first used to assess restructuring and epigenetic repatterning in relation to the strength of reproductive isolation. Asymmetrical reorganization of long terminal repeat retrotransposons (LTR-RTs) predicted to cause conflicting interactions matched differential survival of F1 hybrids. In particular, non-random sequence losses and methylation appeared coherent with the necessary repression of incompatible TE loci in sustaining hybrid viability. Natural hybrid zones between Aegilops geniculata and Aegilops triuncialis were then used to further tackle the consequences of such conflicts for maintaining species boundaries in face of recurrent gene flow. Coherent with insights from experimental populations, conflicting LTR-RTs presented asymmetrical introgression and specific reorganization among natural hybrids. Genomic conflicts involving LTR-RTs are thus highlighted as key incompatibilities supporting reproductive isolation and shaping species boundaries in the long term.<\/p>\n Philippe LE GALL<\/strong><\/p>\n philippe.le-gall@ird.fr<\/p>\n Evolution G\u00e9nomes Comportement Ecologie B\u00e2timent 13 Avenue de la Terrasse 91198 Gif sur Yvette<\/p>\n <\/p>\n Bilan et futur des \u00e9coles de terrain en Afrique Centrale<\/p>\n <\/p>\n Depuis 2011, EGCE (auparavant LEGS\/BEI); a particip\u00e9 \u00e0 la fondation et \u00e0 l’animation scientifique et p\u00e9dagogique des projets d’\u00e9cole de terrain en Afrique Centrale et du consortium scientifique ECOTROP qui y est associ\u00e9. Les actions de recherche port\u00e9es par le Consortium ECOTROP ont pour ambition de lever des verrous scientifiques et techniques pour une meilleure \u00e9valuation et une pr\u00e9diction plus robuste de l’\u00e9volution des ressources naturelles dans le Bassin du Congo. La disponibilit\u00e9 des ressources naturelles et l’efficacit\u00e9 des services \u00e9cosyst\u00e9miques sont des fonctions complexes qui d\u00e9pendent du climat<\/p>\n <\/p>\n <\/p>\n Arnaud Becheler<\/strong><\/p>\n Arnaud.Becheler@universite-paris-saclay.fr<\/p>\n Evolution G\u00e9nomes Comportement Ecologie B\u00e2timent 13 Avenue de la Terrasse 91198 Gif sur Yvette<\/p>\n <\/p>\n Mod\u00e8le d’inf\u00e9rence en d\u00e9mog\u00e9n\u00e9tique environnementale<\/p>\n <\/p>\n Les changements globaux ont des impacts d\u00e9mographiques importants sur la biodiversit\u00e9. Comme ces perturbations laissent des traces identifiables sur la diversit\u00e9 g\u00e9n\u00e9tique; il devient urgent de pouvoir expliquer le lien entre les processus \u00e9volutifs (signal g\u00e9n\u00e9tique) et les facteurs environnementaux (changement globaux) pour pouvoir informer l’avenir probable des populations de l’esp\u00e8ce d’int\u00e9r\u00eat. La g\u00e9n\u00e9tique du paysage a men\u00e9 beaucoup d’efforts en ce sens; en cherchant \u00e0 \u00e9tablir des corr\u00e9lations entre patrons g\u00e9n\u00e9tiques des populations et variables environnementales. Mais ces m\u00e9thodes corr\u00e9latives sont limit\u00e9es dans leurs capacit\u00e9s explicatives. Une famille de mod\u00e8les spatiallement explicites; bas\u00e9s sur la coalescence en environnement h\u00e9t\u00e9rog\u00e8ne; commence \u00e0 \u00e9merger dans la litt\u00e9rature et pourrait permettre de mieux rendre compte des processus \u00e9cologiques \u00e0 l’oeuvre dans nos paysages. Nous proposons ici un mod\u00e8le original permettant l’inf\u00e9rence par Calcul Bay\u00e9sien Approch\u00e9 de param\u00e8tres \u00e9cologiques \u00e0 partir de donn\u00e9es g\u00e9n\u00e9tiques et environnementales; et nous l’appliquons \u00e0 l’\u00e9tude du ph\u00e9nom\u00e8ne d’invasion biologique de Vespa velutina (frelon asiatique) en France.<\/p>\n <\/p>\n <\/p>\n R\u00e9mi Perronne <\/strong>; Isabelle GOLDRINGER1; C\u00e9line SCHOTT<\/p>\n remi.perronne@moulon.inra.fr<\/p>\n G\u00e9n\u00e9tique Quantitative et Evolution-Le Moulon Ferme du Moulon 91190 Gif-sur-Yvette<\/p>\n Etude des relations entre diversit\u00e9 g\u00e9n\u00e9tique du bl\u00e9 tendre et profils de successions culturales en France entre 1980 et 2006<\/p>\n mots-cl\u00e9s : HT*; nombre de vari\u00e9t\u00e9s; diversit\u00e9 N2 de Simpson; diversit\u00e9 g\u00e9n\u00e9tique de Nei ; successions culturales; syst\u00e8me de culture; enqu\u00eate TerUti; historique; occupation du sol; d\u00e9terminant; bl\u00e9 tendre; France; g\u00e9n\u00e9tique<\/p>\n En France; une diminution de la diversit\u00e9 g\u00e9n\u00e9tique du bl\u00e9 tendre a \u00e9t\u00e9 observ\u00e9e durant la seconde moiti\u00e9 du 20\u00e8me si\u00e8cle. Cette tendance varie cependant \u00e0 une \u00e9chelle spatio-temporelle plus fine; sugg\u00e9rant l’\u00e9volution d’un ou plusieurs d\u00e9terminants majeurs.<\/p>\n Dans le cadre de cette \u00e9tude; nous nous sommes focalis\u00e9s sur la p\u00e9riode 1980-2006 et sur une cinquantaine de d\u00e9partements. Parmi les d\u00e9terminants ayant pu influencer la diversit\u00e9 g\u00e9n\u00e9tique du bl\u00e9 tendre; nous avons analys\u00e9 les relations entre diff\u00e9rentes m\u00e9triques caract\u00e9risant cette diversit\u00e9 et les profils de successions culturales; issus du traitement de l’enqu\u00eate TerUti (Minist\u00e8re de l’Agriculture) ceux-ci permettant; en partie; de d\u00e9crire les syst\u00e8mes de cultures et leurs \u00e9volutions. Les m\u00e9triques de diversit\u00e9 s\u00e9lectionn\u00e9es distinguent la richesse vari\u00e9tale; la dominance relative des vari\u00e9t\u00e9s et la diversit\u00e9 g\u00e9n\u00e9tique; int\u00e9grant ou non la surface assol\u00e9e des diff\u00e9rentes vari\u00e9t\u00e9s \u00e0 \u00e9chelle d\u00e9partementale. La d\u00e9finition des profils de successions culturales repose; quant \u00e0 elle; sur l’analyse des proportions relatives de combinaisons de cultures sur trois ann\u00e9es cons\u00e9cutives; pratiqu\u00e9es au cours de deux sous-p\u00e9riodes distinctes (1981-1990 et 1991-2003) d\u00e9termin\u00e9es par des changements de strat\u00e9gie d’\u00e9chantillonnage dans l’enqu\u00eate TerUti.<\/p>\n Deux approches statistiques compl\u00e9mentaires ont \u00e9t\u00e9 r\u00e9alis\u00e9es afin d’\u00e9tudier les relations entre les profils de successions culturales et la diversit\u00e9 du bl\u00e9 tendre. Sur la base d’une proc\u00e9dure associant analyse multivari\u00e9e et clustering; pour chaque variable consid\u00e9r\u00e9e s\u00e9par\u00e9ment; nous avons pu identifier des groupes de d\u00e9partements comparables en termes d’\u00e9volution temporelle de leur diversit\u00e9 et de profils de successions culturales. La comparaison des groupes via un test du \u03a7\u00b2 a permis de mettre en \u00e9vidence que des d\u00e9partements pr\u00e9sentant une \u00e9volution temporelle comparable en termes de diversit\u00e9 g\u00e9n\u00e9tique se caract\u00e9risaient \u00e9galement par des profils de successions culturales similaires. Ce constat a \u00e9t\u00e9 confirm\u00e9 en comparant la distance entre d\u00e9partements; en termes de diversit\u00e9 ou de proportions relatives de combinaisons de cultures sur trois ann\u00e9es; via un test de Mantel. Ce dernier a soulign\u00e9 que les d\u00e9partements dont la diversit\u00e9 moyenne \u00e9tait comparable se caract\u00e9risaient \u00e9galement par des profils de successions culturales similaires; un r\u00e9sultat pouvant \u00eatre g\u00e9n\u00e9ralis\u00e9 \u00e0 l’ensemble des m\u00e9triques et aux deux sous-p\u00e9riodes \u00e9tudi\u00e9es; la p\u00e9riode 1991-2003 pr\u00e9sentant une corr\u00e9lation plus \u00e9lev\u00e9e.<\/p>\n La mise en \u00e9vidence de corr\u00e9lations r\u00e9p\u00e9t\u00e9es entre indicateurs de diversit\u00e9 et profils de successions culturales sugg\u00e8re que celles-ci; directement ou du fait de d\u00e9terminants sous-jacents \u00e0 leurs \u00e9volutions (ex. conditions p\u00e9doclimatiques; structuration des coop\u00e9ratives et des industries de traitements des productions agricoles; \u00e9volution des politiques agricoles); repr\u00e9senteraient l’un des d\u00e9terminants potentiels de la diversit\u00e9 g\u00e9n\u00e9tique du bl\u00e9 tendre. Pour la suite de l’\u00e9tude; des analyses de pistes tenant compte de la complexit\u00e9 des relations causales entre d\u00e9terminants sont envisag\u00e9es.<\/p>\n <\/p>\n Abdel Kader Naino Jika <\/strong><\/p>\n kader.naino@u-psud.fr<\/p>\n Ecologie Syst\u00e9matique et Evolution B\u00e2timent 360 et 362 Universit\u00e9 Paris-Sud 91405 Orsay Cedex<\/p>\n Evolution of pearl millet diversity driven by farmer’s practices: a multi-level assessment<\/p>\n Growing and exchanging a portofolio of crops and varieties which are complementary in some aspects (agronomic or nutritionally) is a key factor for food security in Sahel. However; patterns and dynamics of crop diversity assessed at different levels (genetics; biochemistry; agronomic) are still poorly understood. We studied the relationship between neutral genetic diversity; phenology and seed biochemical compounds in pearl millet landraces; a major crop in Sahel. Our study focused on landraces grown in south western Niger; in an area corresponding to two ethno-linguistic zones (Zarma and Hausa populations). The purpose was to better understand the interplay of gene flow and farmers’ selection in the evolution of varietal types (mainly those classified as early and late flowering by farmers themselves) in this area where contrasted rainfall patterns prevail.<\/p>\n Neutral genetic diversity at this scale is globally not correlated to rainfall gradients but is rather structured in two main clusters which coincide with human ethno-linguistic diversity. This result suggests the existence of social barriers to effective gene flow between ethno-linguistic groups. In addition there is very little or no differentiation between landraces grown by the same ethno linguistic group for neutral markers. This confirms seed flow; in this crop having high social and cultural values; may be strongly ruled by social factors. Our results also show the very weak differentiation at neutral markers and for cycle-length of some landraces grown in same localities and classified by farmers as early and late flowering landraces. This confirms the existence of pollen flow between them; as shown by other authors; especially in the most northern (drier) areas. However; we observed a clear differentiation between these varietal types for post harvest characters that are commonly the only used by farmers to select seeds for next generation. This suggests farmers practices are operating to maintain perceptual distinction between their different landraces but not always to maintain phenological differences; especially where droughts are more frequent. Finally; we used a proteomic approach to carry out one of the first assessment of diversity for seed biochemical compounds of a collection of landraces which correspond to different culinary uses and organoleptic characteristics.<\/p>\n <\/p>\n Keywords : pearl millet population genetic structure; gene flow; seeds exchanges; genetic resources; genetic diversity; cultural diversity; landraces; biochemical diversity; phenology; genotype environment interaction.<\/p>\n <\/p>\n <\/p>\n Marie Vaugoyeau<\/strong><\/p>\n marie.vaugoyeau@gmail.com<\/p>\n Ecologie Syst\u00e9matique et Evolution B\u00e2timent 360 et 362 Universit\u00e9 Paris-Sud 91405 Orsay Cedex<\/p>\n <\/p>\n Urbanisation has variable influences on the breeding phenology of four passerine birds across Europe and North Africa<\/p>\n <\/p>\n The increase in size of urban human populations results in habitat conversion. Such urban areas have specific environmental characteristics; which influence the population dynamics of plants and animals. For example; date of bud break is advanced in urban than in rural areas. In birds; breeding success is determined by the synchrony between timing of breeding and peak food abundance. Caterpillars are important food for nestlings in our studied species and their abundance is influenced by environmental factors like temperature or date of bud break. Higher temperature and advanced date of bud break measure in urban areas could advance peak caterpillar abundance. Does urbanisation influence timing of breeding in passerine birds across North Africa and Europe? We analysed the timing of breeding in relation to urbanisation in 197 nest box plots across Europe for four species of hole-nesters: blue tits (Cyanistes caeruleus); great tits (Parus major); collared flycatchers (Ficedula albicollis) and pied flycatchers (Ficedula hypoleuca). We estimated urban intensity as the density of building around study plots measured on orthophoto of Google Earth. Laying dates of blue tits; great tits and collared flycatchers advanced with increasing urbanisation while this was not the case for pied flycatchers. This is the first large-scale study showing a species-dependent major effect of urbanisation on the timing of breeding. As egg laying dates are directly related to female behaviour; then it opens up new ways to study the influence of urbanisation on female breeding behaviours.<\/p>\n <\/p>\n Elodie Marchadie<\/strong><\/p>\n elodie.marchadier@u-psud.fr<\/p>\n G\u00e9n\u00e9tique Quantitative et Evolution-Le Moulon Ferme du Moulon 91190 Gif-sur-Yvette<\/p>\n <\/p>\n DECODING THE GENETIC ARCHITECTURE OF GROWTH AND WATER STRESS RESPONSE IN ARABIDOPSIS THALIANA<\/p>\n <\/p>\n Maintaining high quality crop production under water limited availability is a major challenge for the scientific community in the next years. Judging from their worldwide distribution; plants have an inherent ability to adapt to fluctuating environmental conditions. Our work aims to better understand the evolutionary mechanisms which lead to the diversity of strategies plants have developed to acclimate to water stress conditions. Ecologically distant Arabidopsis thaliana accessions constitute a valuable source of alleles to carry out this investigation. This project used genome-wide quantitative molecular genetics to better understand a very integrative and classical quantitative trait\u00a0: growth in interaction with the environment; especially in water stress conditions. We used a unique high-troughput phenotyping robot; the Phenoscope combined to association genetics and fine-mapping approaches. It allowed to pinpoint a significant number of QTLs. In addition to the main results of the project; we will also discuss the strategies we developped to dissect the complex genetic architecture of integrative traits.<\/p>\n <\/p>\n <\/p>\n St\u00e9phane Dupas<\/strong><\/p>\n dupas@universite-paris-saclay.fr<\/p>\n Evolution G\u00e9nomes Comportement Ecologie B\u00e2timent 13 Avenue de la Terrasse 91198 Gif sur Yvette<\/p>\n <\/p>\n R\u00e9ductionisme ou holisme; disiciplinaire ou transdisicplinaire\u00a0: Une lecture thermodynamique de recherches multi\u00e9chelles men\u00e9es \u00e0 l’IDEEV<\/p>\n <\/p>\n L’\u00e9volution des syst\u00e8mes biologiques d\u00e9pend de dynamiques d’interactions; qui \u00e0 la fois; r\u00e9sultent et sont et \u00e0 l’origine; de l’information adapt\u00e9e contenue dans les g\u00e8nes et les cerveaux. Cette information intelligente se transmet et se multiplie \u00e0 chaque \u00e9chelle d’organisation du g\u00e8ne au socio\u00e9cosyst\u00e8me. La th\u00e9orie thermodynamique propose qu’elle se multiplie d’autant plus qu’elle contribue \u00e0 la dissipation d’\u00e9nergie libre du syst\u00e8me ouvert qu’elle constitue. L’intelligence d’une bact\u00e9rie; par exemple consiste \u00e0 orienter ses d\u00e9placements vers les zones de plus forte concentration de nutriments afin d’en r\u00e9duire la concentration. En extrayant du p\u00e9trole pour augmenter notre puissance \u00e9nerg\u00e9tique; nous d\u00e9placer; nous nourrir; et cro\u00eetre d\u00e9mographiquement; nous dissipons aussi au maximum l’\u00e9nergie libre contenus dans des gradients. L’hypoth\u00e8se formul\u00e9e par les physiciens est donc que ces syst\u00e8mes thermodynamiques ouverts se structurent et s’adaptent pour maximiser le flux de dissipation d’\u00e9nergie qui les traverse. Mais l’adaptation des niveaux sup\u00e9rieurs ne peut faire qu’en coordination avec celle des niveaux inf\u00e9rieurs. Il y a parfois conflit entropique entre \u00e9chelles.<\/p>\n Je pr\u00e9senterai ces m\u00e9canismes adaptatifs et leur expression thermodynamique \u00e0 \u0153uvre dans les objets de recherches men\u00e9es dans l’IDEEV; \u00e0 tous les niveaux du socio\u00e9cosyst\u00e8me. A chaque niveau on observe des processus apparent\u00e9s de dissipation d’\u00e9nergie libre contenue dans des gradients. Chacun des syst\u00e8mes \u00e9tudi\u00e9s est aussi le lieu de conflits entres structures dissipatives; \u00e9rodant les gradients et pouvant provoquer l’effondrement de niveaux sup\u00e9rieurs. Je proposerai une lecture thermodynamique des m\u00e9canismes g\u00e9n\u00e9tiques et neuronaux d’adaptation \u00e9tudi\u00e9s \u00e0 l’IDEEV; qu’il s’agisse de flux d’information au sein de soci\u00e9t\u00e9s de drosophile; de l’\u00e9volution des g\u00e8nes distorteurs de s\u00e9gr\u00e9gation; de l’\u00e9volution de la biodiversit\u00e9 cultiv\u00e9e; ou du devenir des socio\u00e9cosyst\u00e8mes face aux changements globaux. Je discuterai des conflits qu’ils peuvent engendrer entre unit\u00e9s et \u00e9chelles de l’adaptation. Je montrerai que les adaptations des \u00e9chelles sup\u00e9rieures ne peuvent \u00eatre comprises qu’en comprenant les processus \u00e0 l’\u0153uvre aux \u00e9chelles inf\u00e9rieures. Les propri\u00e9t\u00e9s \u00e9mergentes s’observent aussi au sein de chaque discipline; de chaque objet. Quels que soient les niveaux; les disciplines; l’approche r\u00e9ductionniste est donc n\u00e9cessaire et ins\u00e9parable de l’approche int\u00e9gr\u00e9e holistique. J’argumenterai donc sur l’int\u00e9r\u00eat d’\u00e9tablir une typologie des m\u00e9canismes de l’adaptation aux diff\u00e9rentes \u00e9chelles par l’articulation de recherches disciplinaires fortes.<\/p>\n <\/p>\n <\/p>\n Sylvie R\u00e9taux<\/strong><\/p>\n retaux@inaf.cnrs-gif.fr<\/p>\n Institut des Neurosciences Paris-Saclay B\u00e2timent 32-33 Avenue de la Terrasse 91198 Gif sur Yvette<\/p>\n <\/p>\n Evolution of the olfactory system in blind cavefish<\/p>\n <\/p>\n Natural variations in sensory systems constitute adaptive responses to the environment.We have compared the development of the sensory placodes in the blind; cave-adapted morph and the eyed river-dwelling morph of the fish Astyanax mexicanus. Focusing on the lens and the olfactory placodes; we found a trade-off between these two sensory components in the two morphs: from neural plate stage onwards; cavefish have larger olfactory placodes and smaller lens placodes. Searching for the developmental mechanisms underlying cavefish sensory evolution; we analyzed the roles of Shh hyper-signaling from the ventral midline; Fgf8 heterochronic signaling from the rostral forebrain; and modifications in Bmp4 expression dynamics in the prechordal plate of cavefish embryos. Using pharmacological treatments and injections to interfere with these three signaling systems at the end of gastrulation; we establish a regulatory network in which the subtle modifications of Shh; Fgf8 and Bmp4 signaling in space and time in cavefish embryos explain the observed changes and trade-off in lens versus olfactory placode fate; and account for the observed size of their sensory derivatives. We suggest that such evolutionary developmental mechanisms may be used throughout vertebrates to drive adaptive sensory specializations according to lifestyles and habitats. Finally; we have started correlating the apparent olfactory specialization of cavefish with their olfactory performances in behavioral tests.<\/p>\n <\/p>\n <\/p>\n Stefan Little<\/strong><\/p>\n stefan.little@u-psud.fr<\/p>\n Ecologie Syst\u00e9matique et Evolution B\u00e2timent 360 et 362 Universit\u00e9 Paris-Sud 91405 Orsay Cedex<\/p>\n <\/p>\n Integrating transcriptomes into the comparative floral evolution of magnoliids<\/p>\n <\/p>\n Magnoliidae (4 orders; 20 families; ca. 10;000 spp.) are remarkably diverse in floral structure and represent a microcosm of floral evolution seen across angiosperms. The MAGNIPHY project aims to study floral evolution in Magnoliidae using a multidisciplinary approach integrating molecular phylogenetics; morphology; paleobotany; and transcriptomics. This effort includes generation of densely sampled phylogenetic hypotheses (199 species; 75% of genera; all families) dated using ten carefully reviewed fossil age constraints; trait reconstructions suggest that ancestrally; flowers of Magnoliidae had whorled; trimerous and differentiated perianth. In order to correlate floral gene expression patterns with floral morphology and our evolutionary reconstructions; we are sequencing whole-bud floral transcriptomes from representatives across Magnoliidae. So far; preliminary transcriptomic data from six families reveal several MADS-box genes as well as TCP transcription factors with elevated expression. MADS-box genes show high sequence similarity with genes of B; C; and E function; central in floral organ differentiation in model organisms (i.e.; AGAMOUS; APETALA3; PISTILLATA; SEPALLATA). Since existing evo-devo hypotheses about floral morphology are primarily based on distantly related model plants; the integrative approach of the MAGNIPHY project should help improve our models of the mechanisms of floral diversification in Magnoliidae and the deeper splits in angiosperm evolution.<\/p>\n <\/p>\n <\/p>\n Elisabeth Reyes<\/strong><\/p>\n elisabeth.reyes@u-psud.fr<\/p>\n Ecologie Syst\u00e9matique et Evolution B\u00e2timent 360 et 362 Universit\u00e9 Paris-Sud 91405 Orsay Cedex<\/p>\n <\/p>\n Floral symmetry shifted 204 times in angiosperms<\/p>\n <\/p>\n The number of species in families of flowering plants ranges from 1 to more than 20;000; which is one of the symptoms of a highly uneven distribution of diversity in angiosperms. One of the commonly proposed factors in shaping this uneven distribution is the origin of key innovations; which are traits that give the clades possessing them a significant advantage over close relatives lacking them. Clades possessing such an advantage are assumed to produce more species per unit of time; with a consequence of being more speciose than their close relatives in present day. One generally accepted key innovation is floral zygomorphy (bilateral symmetry); which is considered advantageous over actinomorphy (radial symmetry) because zygomorphic flowers have more efficient pollen transfer via limiting pollinator approach angles. The presumed influence of zygomorphy on diversification rates has been argued mostly through the comparison of closely related clades with contrasting floral symmetry. This approach has ignored the broader picture in which many speciose angiosperm families are completely actinomorphic and the finer pattern of changes in floral symmetry. This observation has led us to question the extent to which floral zygomorphy can be considered a key innovation in angiosperms as a whole. To begin answering this question; we need to know where and how many times zygomorphy has originated in the angiosperm phylogeny. We recorded perianth symmetry from more than 700 species; selected to represent all 61 orders and 426 currently accepted families of angiosperms and to include all presumed origins of perianth zygomorphy. We then reconstructed the evolution of perianth symmetry on a consensus backbone tree; using parsimony. We found perianth zygomorphy in 31 orders and 108 families. There was a minimum of 124 origins; almost the double of what was previously estimated; and 80 reversals to actinomorphy. Among the origins; two were in magnoliids; 28 in monocots; 17 in basal eudicots; 32 in superrosids and 45 in superasterids. Among the reversals; 8 were in monocots; 4 in basal eudicots; 28 in superrosids and 40 in superasterids. Our next step will be to test the extent to which these shifts in floral symmetry are linked to shifts in species diversification.<\/p>\n <\/p>\n <\/p>\n Rafael Isaac Ponce Toledo<\/strong><\/p>\n rafael.ponce@u-psud.fr<\/p>\n Ecologie Syst\u00e9matique et Evolution B\u00e2timent 360 et 362 Universit\u00e9 Paris-Sud 91405 Orsay Cedex<\/p>\n <\/p>\n Phylogenomics traces the ancestor of primary plastids back to an early branching cyanobacterium<\/p>\n <\/p>\n Photosynthesis emerged in eukaryotes by the endosymbiosis of a cyanobacterium within a heterotrophic host. This gave rise to the supergroup called Archaeplastida; comprising Rhodophyta; Viridiplantae and Glaucophyta. The identity of the two partners involved in the primary endosymbiosis is still debated. Using available complete genome sequences and homemade genomic data; we performed phylogenomic analyses to infer the closest extant cyanobacterial relative of primary plastids. We assembled three concatenated datasets containing 102 plastid-encoded proteins; 118 nucleus-encoded proteins acquired via endosymbiotic gene transfer; and the plastid 16S+23S rRNA cluster; respectively. All our phylogenetic reconstructions strongly support that the ancestor of primary plastids was an early-branching cyanobacterium related to Gloeomargarita lithophora; the first cultured member of a recently discovered cyanobacterial lineage widely present in stromatolites and thermophilic microbial mats.<\/p>\n <\/p>\n <\/p>\n Ludwig Jardillier<\/strong><\/p>\n ludwig.jardillier@u-psud.fr<\/p>\n Ecologie Syst\u00e9matique et Evolution B\u00e2timent 360 et 362 Universit\u00e9 Paris-Sud 91405 Orsay Cedex<\/p>\n <\/p>\n Small freshwater ecosystems harbour complex protist communities characterised by seasonal dynamics and resilience<\/p>\n <\/p>\n Over the last decades; most of the studies investigating the diversity and dynamics of the small protists (cells 0.2-5 \u00b5m in size) have been restricted to large freshwater ecosystems and marine environments because of the surface they represent on Earth. However; small continental aquatic systems (<0.1 km2) cover at least the same surface as larger freshwater bodies. They are numerous and characterised by a wide range of environmental conditions. We thus monitored the dynamics of the small protists for 2 years (April 2011 to April 2013) in five small freshwater systems differing in their environmental conditions and trophic status; including 4 ponds and one stream in the North-Western France. Their composition was determined based on 454-pyrosequencing of 18S rRNA genes. A large set of environmental parameters was measured concomitantly. Multivariate statistical analyses were used to explore the ecology of the small protists in these freshwater systems. The protist diversity was high with sequences affiliated to all recognized supergroups. New phylotypes were detected every month in all ecosystems. A few OTUs affiliated to taxa previously thought restricted to marine environments (e.g. group MAST-3) while other OTUs were only detected in freshwater systems (e.g. group HAP-1). The community composition differed among the five ecosystems over the 2-years survey; with only 50 OTUs from a total of 3;742 OTUs shared by the 5 ecosystems. A clear seasonal pattern was observed in each ecosystem despite a complex temporal dynamics of the high-rank taxa detected. Low-abundance OTUs represented the vast majority of the community and showed very different dynamics; appearing occasionally; remaining at low frequencies or instead reaching high frequencies. In addition; severe drought events occurred in one of the ponds and the stream for 1 to 5 months. Each time; the protist community showed a rapid resilience that occurred within a month after the recovery of the water level; with both community composition and structure being very similar to those observed prior to the drought event.<\/p>\n <\/p>\n <\/p>\n <\/p>\n Nicolas Pollet<\/strong><\/p>\n Nicolas.Pollet@universite-paris-saclay.fr<\/p>\n Evolution G\u00e9nomes Comportement Ecologie B\u00e2timent 13 Avenue de la Terrasse 91198 Gif sur Yvette<\/p>\n <\/p>\n Phylogenetic and metabolic profiles of an amphibian gut microbiome<\/p>\n <\/p>\n Amphibian decline in the wild is a global concern. Chemical pollutants acting on detoxification; endocrine and immune systems are some of the causes of this decline. Amphibian pathogens are another possible cause of decline. All amphibians are sensitive to environmental changes because the completion of their metamorphosis relies on delicate regulations of their neuroendocrine and immune systems. We also know that all animals live in a world dominated by bacteria. In the last twenty years we have learned that commensal microbes are essential regulators of animal physiology and especially immunology. Yet we do not know much on amphibian gut microflora; wether in the tadpole or in the adult. We set out to characterize the taxonomic and metabolic profiles of tadpole’s gut microbiome in Xenopus; a laboratory model. We used metagenomic and metatranscriptomic approaches; completed by cytometry to unravel the microflora of the tadpole’s gut during development. Our study will lay the foundation for future research on the response of the microbiome of natural amphibian populations to environmental changes.<\/p>\n <\/p>\n <\/p>\n <\/p>\n Gabriel Luz Wallau, Arnaud Le Rouzic, Pierre Capy, Elgion Loreto, Aur\u00e9lie Hua Van<\/strong><\/p>\n Aurelie.Hua-Van@universite-paris-saclay.fr<\/p>\n Evolution G\u00e9nomes Comportement Ecologie B\u00e2timent 13 Avenue de la Terrasse 91198 Gif sur Yvette<\/p>\n \u00a0<\/strong><\/p>\n VHICA: A new method to discriminate between vertical and horizontal transposon transfer: application to the mariner<\/em> family within Drosophila<\/em><\/p>\n Transposable elements TEs are genomic repeated sequences that display complex evolutionary patterns. They are usually inherited vertically, but can occasionally be transmitted between sexually-independent species, through so-called Horizontal Transposon Transfers (HTTs). HTT is supposed to be an essential step in the life cycle of TEs, which are otherwise destined for eventual decay. They can also have a great impact on the host genome evolution. However, the extent of HTTs in eukaryotes is largely unknown, due to the lack of efficient, statistically-supported methods that can be applied to multiple species sequence datasets. In the present study, we developed a new automated method available as a R package \u201cVHICA\u201d, that discriminates whether a given TE family was vertically or horizontally transferred. The method is well suited for whole genome sequences, and applicable to several TEs and species at the same time. We first validated our method using Drosophila<\/em> TE families with well-known evolutionary histories, displaying both HTT and vertical transmission. We then tested 25 different lineages of mariner <\/em>elements recently characterized in 20 Drosophila <\/em>genomes, and found HTTs in 23 of them. Furthermore, several independent HTT events could often be detected within the same mariner<\/em> lineage.<\/p>\n <\/p>\n <\/p>\n Johann Joets<\/strong><\/p>\n joets@moulon.inra.fr<\/p>\n G\u00e9n\u00e9tique Quantitative et Evolution-Le Moulon Ferme du Moulon 91190 Gif-sur-Yvette<\/p>\n <\/p>\n Structural and functional specificities of the genome of the European maize line FV2.<\/p>\n <\/p>\n Plant genomes exhibit tremendous amount of structural variation (SV); including copy number variation (CNV); presence\/absence variation (PAV; where an individual has 0 copy) as well as inversion and translocation. Recently more than 4000 novel maize transcripts absent from B73 were identified from 500 maize inbred lines (1). This level of structural variation makes it difficult understanding the genome of a species based only on the reference sequence obtained from an individual. The whole genetic information for species should be view as pan-genome made of a core genome shared by any individual plus a variably distributed genome (2). CNV and PAV were found over-represented in genome-wide association studies (GWAS) for several traits in maize and may explain some variation not captured by single nucleotide polymorphism (SNP). In order to address this point we have devised several bioinformatic methods to assemble a pan-genomic sequence draft based on two maize genotypes (B73 and FV2). We have identified more than 9000 novel sequences absent from B73 ranging from 1KB to 87 kb for a cumulated size of 90 Mb. More than 1000 of these sequences were anchored to B73. Short-read sequencing from 27 maize lines were aligned against this pan-genome draft and a statistical methods was developed to type for presence and absence of these novel sequences. The genetic diversity of the 27 maize lines was studied from PAV and compared to the diversity captured from SNPs. We also investigated the level of LD between anchored PAV and neighboring SNPs. Structural annotation of novels sequences revealed hundreds of genes or gene fragments we study the expression in a dozen conditions.<\/p>\n <\/p>\n <\/p>\n Ariane Gratias-Weill<\/strong><\/p>\n ariane.gratias-weill@u-psud.fr<\/p>\n Institute of Plant Science Paris-Saclay B\u00e2timent 630; Universit\u00e9 Paris-Sud; 91405 Orsay Cedex<\/p>\n <\/p>\n Does pathogen infection have an impact of meiotic recombination in plants?<\/p>\n <\/p>\n Plants are continuously exposed to biotic stresses and have in turn developed resistance strategies to counteract pathogen attack. One of these mechanisms is based on resistance proteins (R) encoded by the plant genome; that specifically recognize pathogen effectors. The major class of R genes is constituted by NB-LRR genes. Most of them are organized in gene clusters that could favor sequence exchange between NB-LRR genes. This could contribute to R gene evolution dynamics. Recently; several publications have suggested the existence of a Systemic Recombination Signal (SRS) that propagates in plant tissues after a pathogen infection and is associated with an increase of genomic instability in somatic cells in uninfected tissues. Moreover; in progeny of infected Tobacco; a higher frequency of chromosomal rearrangements has been described at loci that present homology with the N-gene LRR region. These scarce data suggest the existence of a link between the perception of a biotic stress and the production of genetic diversity. In order to test if pathogen infection can increase DNA recombination in MEIOTIC cells; and particularly at NB-LRR loci; we used Fluorescent Tagged Lines of Arabidopsis. We measured the meiotic recombination rate in two regions of chromosome 5 after infection with the bacteria Pseudomonas syringae : in one interval containing a R-gene cluster and in one without. In both intervals; we have showed no significant difference of genetic recombination frequency between infected- and mock- inoculated plants.<\/p>\n <\/p>\n <\/p>\n <\/p>\n Vanesa Sanchez,<\/strong> VS Garcia de la Torre and S. Merlot<\/p>\n vanesa.sanchez@i2bc.paris-saclay.fr<\/p>\n Institut de Biologie Int\u00e9grative de la cellule B\u00e2timent 22 Avenue de la Terrasse 91198 Gif-sur-Yvette<\/p>\n <\/p>\n Genomics and Diversity of Ni hyperaccumulation in plants<\/p>\n <\/p>\n Nickel (Ni) is widely used metal in modern societies; but its mining has a strong impact on the environment and biodiversity. Ni is an essential element but becomes toxic at high concentration for most living organisms. However; 400 plant species (42 families); called hyperaccumulators; found on serpentine (ultramafic) soil in Europe; New Caledonia and Cuba; are able to accumulate tremendous amount of Ni (>0;1% of dry weight) in their leaves. These plants receive a growing interest because of their potential use in Phytoremediation and Phytomining sustainable technologies and also because they can be used to understand the molecular mechanisms involved in Ni tolerance and hyperaccumulation and the evolution of these complex traits. Our work aims to study the transcriptomes of evolutionary distant Ni hyperaccumulators to identify target genes and molecules important for Ni accumulation and study the evolution of these mechanisms in plants. Using RNA-Seq strategy we generated original transcriptomes by de novo<\/em> assembly from Noccaea (Brassicaceae); Psychotria (Rubiaceae); Geissois (Cunoniaceae) and Leucocroton (Euphorbiaceae) genera found in France; New Caledonia and Cuba. Using these transcriptomes as references we compared gene expression between Ni hyperaccumulators and the closely related non-accumulator species. The first results of these analyses indicate that a family of metal transporter can be evolutionary linked Ni tolerance and hyperaccumulation in plants. The results of our work will be valuable for the development of phytoremediation and phytomining technologies.<\/p>\n <\/p>\n <\/p>\n <\/p>\n Fr\u00e9d\u00e9ric Marion-Poll<\/strong><\/p>\n frederic.marion-poll@universite-paris-saclay.fr<\/p>\n Evolution G\u00e9nomes Comportement Ecologie B\u00e2timent 13 Avenue de la Terrasse 91198 Gif sur Yvette<\/p>\n <\/p>\n Des substances am\u00e8res pour prot\u00e9ger les plantes?<\/p>\n <\/p>\n Les insecticides permettent de lutter efficacement contre les insectes; et il est commun\u00e9ment accept\u00e9 que beaucoup d’esp\u00e8ces d’insectes s’y adaptent rapidement; soit en augmentant l’expression d’enzymes de d\u00e9toxification comme des P450; soit gr\u00e2ce \u00e0 des mutations du site d’action de la cible de la mol\u00e9cule active. Par exemple; une \u00e9quipe de notre unit\u00e9 a montr\u00e9 chez Drosophila<\/em> simulans<\/em> que les populations de mouches expos\u00e9es au DDT portent encore aujourd’hui un g\u00e8ne de r\u00e9sistance; ce qui sugg\u00e8re que le co\u00fbt de ces r\u00e9sistances n’est pas forc\u00e9ment tr\u00e8s \u00e9lev\u00e9. Des coll\u00e8gues de l’universit\u00e9 de Texas A&M ont r\u00e9cemment d\u00e9crit un autre m\u00e9canisme de r\u00e9sistance chez des blattes expos\u00e9es \u00e0 un insecticide associ\u00e9 \u00e0 un pi\u00e8ge alimentaire. Ces blattes r\u00e9sistantes ne sont pas plus r\u00e9sistantes \u00e0 l’insecticide que des blattes issues de populations naturelles; mais le glucose qui est pr\u00e9sent dans les pi\u00e8ges est devenu amer. Cette observation souligne le r\u00f4le que peuvent jouer le comportement et les organes sensoriels dans l’adaptation des insectes \u00e0 des substances x\u00e9nobiotiques. De mani\u00e8re plus g\u00e9n\u00e9rale; associer une substance insecticide \u00e0 des substances am\u00e8res ou r\u00e9pulsives semble plus pertinent que l’utilisation d’un insecticide seul \u00e0 condition que les substances associ\u00e9es soit d\u00e9tectables sensoriellement. C’est en tout cas bien ce qui semble se passer chez les plantes sauvages qui sont souvent tr\u00e8s riches en compos\u00e9s amers pour leur pr\u00e9dateurs et qui utiliseraient ainsi un apos\u00e9matisme chimique.<\/p>\n <\/p>\n Lars Chittka<\/strong>, Mathieu Lihoreau, Joe Woodgate, James Makinson, Nigel Raine, Jason Lim, Andy Reynolds<\/p>\n l.chittka@qmul.ac.uk<\/a><\/p>\n Queen Mary University of London Mile End Road London E1 4NS<\/p>\n <\/p>\n Spatial memory in the economy of nature: bees as a model<\/p>\n <\/p>\n Central place foragers, such as pollinating bees, often develop circuits (traplines) to visit multiple foraging sites in a manner that minimizes overall travel distance. Despite being taxonomically widespread, these routing behaviours remain poorly understood due to the difficulty of tracking the foraging history of animals in the wild. Using radar tracking, we explore how bees develop and optimise foraging routes over large spatial scales. Stable traplines that linked together all the flowers in an optimal sequence were established after several dozen foraging bouts, during which time only a small portion of possible routes were tried. When the flower array was experimentally altered, bees engaged in localised search flights, a strategy that can facilitate the discovery of a new flower and its integration into a novel optimal trapline. Based on these observations, we developed and tested an iterative improvement heuristic to capture how bees could learn and refine their routes each time a shorter route is found. Our findings suggest that complex dynamic routing problems can be solved by small-brained animals using simple learning heuristics, without the need for a cognitive map.<\/p>\n <\/p>\n <\/p>\n <\/p>\n <\/p>\n <\/p>\n <\/p>\n <\/p>\n Posters<\/p>\n R\u00e9mi Perronne<\/strong>, Marie Stetzler, J\u00e9r\u00f4me Enjalbert, Vincent Cellier, Isabelle Goldringer, Nicolas Turenne, Jean-No\u00ebl Aubertot<\/p>\n remi.perronne@moulon.inra.fr<\/p>\n UMR 0320 G\u00e9n\u00e9tique Quantitative et Evolution -Le Moulon 91190 Gif-sur-Yvette; France<\/p>\n <\/p>\n Evolution spatio-temporelle de la pression pathog\u00e8ne en bl\u00e9 tendre en France: \u00e9tude de la coexistence des rouilles et de la septoriose<\/p>\n Mots-cl\u00e9s : rouille jaune (Puccinia striiformis f.sp. tritici); rouille brune (Puccinia recondita f. sp. tritici); septoriose (Mycosphaerella graminicola); analyse en composantes principales (ACP); avertissements agricoles; bilans de campagne<\/p>\n De nombreux mod\u00e8les de d\u00e9veloppement des diff\u00e9rents pathog\u00e8nes foliaires majeurs du bl\u00e9 ont \u00e9t\u00e9 cr\u00e9\u00e9s au cours des derni\u00e8res d\u00e9cennies; ayant pour objectif d’estimer la dynamique de croissance du pathog\u00e8ne; ainsi que les risques li\u00e9s \u00e0 celle-ci \u00e0 une \u00e9chelle spatio-temporelle fine. Parall\u00e8lement; l’\u00e9volution de la pression d’une gamme de pathog\u00e8nes coexistant au sein d’une culture \u00e0 l’\u00e9chelle de plusieurs d\u00e9cennies n’a \u00e9t\u00e9 que peu \u00e9tudi\u00e9e jusqu’\u00e0 pr\u00e9sent. En France; les Services de la Protection des V\u00e9g\u00e9taux qui r\u00e9digeaient les Avertissements Agricoles; pr\u00e9sentaient chaque ann\u00e9e et dans chaque r\u00e9gion; un bilan de campagne ayant pour objectif de caract\u00e9riser les stress biotiques observ\u00e9s au cours du cycle cultural \u00e9coul\u00e9; parmi lesquels la rouille jaune (Puccinia striiformis f.sp. tritici); la rouille brune (Puccinia recondita f. sp. tritici) et la septoriose (Mycosphaerella graminicola) pour la culture de bl\u00e9 tendre (Triticum aestivum). La plateforme PESTOBSERVER (https:\/\/pestobserver.eu) donne; depuis peu; acc\u00e8s aux Avertissements Agricoles et aux donn\u00e9es qu’ils contiennent. Dans le cadre de cette \u00e9tude; nous nous sommes focalis\u00e9s sur l’\u00e9volution spatio-temporelle de la pression de rouille jaune entre 1996 et 2006 \u00e0 \u00e9chelle r\u00e9gionale; puis nous avons compar\u00e9 cette l’\u00e9volution \u00e0 celle de la rouille brune et de la septoriose afin d’identifier d’\u00e9ventuelles corr\u00e9lations entre les niveaux d’attaque des diff\u00e9rents pathog\u00e8nes. Dans un premier temps; la r\u00e9-interpr\u00e9tation des bilans de campagne a n\u00e9cessit\u00e9 une double lecture des documents afin d’identifier les informations cl\u00e9s. Le niveau d’attaque indiqu\u00e9 dans ceux-ci; distinguant 7 classes; a \u00e9t\u00e9 compar\u00e9 aux informations relatives \u00e0 l’expression de la maladie foliaire au cours de l’ensemble du cycle cultural; tenant compte des informations vari\u00e9tales lorsque celles-ci \u00e9taient disponibles. Puis; sur la base d’une analyse multivari\u00e9e; nous avons pu identifier quatre groupes de r\u00e9gions ayant pr\u00e9sent\u00e9 des profils de pressions pathog\u00e8nes distincts pour la rouille jaune au cours de la p\u00e9riode d’\u00e9tude. Une proc\u00e9dure de comparaison des profils de pression a par ailleurs permis d’identifier une absence de corr\u00e9lation entre les niveaux d’attaque des trois pathog\u00e8nes \u00e9tudi\u00e9s dans toutes les r\u00e9gions; \u00e0 l’exception des r\u00e9gions Midi-Pyr\u00e9n\u00e9es et Aquitaine qui ont pr\u00e9sent\u00e9 un risque d’attaque moyen \u00e0 fort pour les trois pathog\u00e8nes entre 1996 et 2000. Pour conclure; la r\u00e9interpr\u00e9tation des Avertissements Agricoles constitue une source pr\u00e9cieuse d’information; contribuant \u00e0 la compr\u00e9hension des profils de coexistence entre bioagresseurs des cultures \u00e0 l’\u00e9chelle de plusieurs d\u00e9cennies. Pour la suite de l’\u00e9tude; l’analyse des patrons de coexistence s’appuiera sur une mod\u00e9lisation tenant compte des pr\u00e9f\u00e9rences climatiques de chaque pathog\u00e8ne. Par ailleurs; d’autres pathog\u00e8nes foliaires et des \u00e9pis seront \u00e9tudi\u00e9s.<\/p>\n Emma Forst<\/strong><\/p>\n emma.forst@moulon.inra.fr<\/p>\n UMR 0320 G\u00e9n\u00e9tique Quantitative et Evolution -Le Moulon 91190 Gif-sur-Yvette; France<\/p>\n <\/p>\n S\u00e9lection pour l’aptitude \u00e0 la culture en m\u00e9lange<\/p>\n <\/p>\n Doctorante en premi\u00e8re ann\u00e9e \u00e0 l’INRA du Moulon (GQE -Le Moulon); je souhaite pr\u00e9senter un poster sur mes premiers r\u00e9sultats concernant le d\u00e9veloppement de m\u00e9thodes de s\u00e9lection pour les m\u00e9langes pluri-g\u00e9notypiques de bl\u00e9 tendre. Le projet vise \u00e0 utiliser la diversit\u00e9 g\u00e9n\u00e9tique cultiv\u00e9e intra-parcelle comme un levier pour d\u00e9velopper et soutenir les pratiques agro-\u00e9cologiques dans le contexte d’un accroissement de la stochasticit\u00e9 climatique inter-annuelle et de la r\u00e9duction des intrants. \u00a0En effet; la diversit\u00e9 g\u00e9n\u00e9tique intra-parcelle (m\u00e9lange de g\u00e9notypes) pr\u00e9sente un int\u00e9r\u00eat agronomique (stabilit\u00e9 du rendement et de la qualit\u00e9) et fournit des services de r\u00e9gulation biologiques tels que la r\u00e9duction des maladies. Cependant les vari\u00e9t\u00e9s utilis\u00e9es pour la culture en m\u00e9lange ont \u00e9t\u00e9 s\u00e9lectionn\u00e9es en conditions de culture pure et son souvent assembl\u00e9es sur les seuls crit\u00e8res de r\u00e9sistances aux maladies et d’homog\u00e9n\u00e9it\u00e9 des ph\u00e9nologies. Il est alors possible d’optimiser l’assemblage des vari\u00e9t\u00e9s dans les m\u00e9langes en prenant en compte d’autres crit\u00e8res d’association et en d\u00e9veloppant des m\u00e9thodes de s\u00e9lection sp\u00e9cifiques pour la culture en m\u00e9lange. Pour cela; des m\u00e9thodes de s\u00e9lection sont d\u00e9velopp\u00e9es et \u00e9valu\u00e9es afin de favoriser l’aptitude \u00e0 l’association des g\u00e9notypes (par opposition \u00e0 leur performance en pur). L’\u00e9laboration de telles strat\u00e9gies de s\u00e9lection repose sur la mobilisation de th\u00e9ories en g\u00e9n\u00e9tique quantitatives d\u00e9velopp\u00e9es initialement pour raisonner l’aptitude \u00e0 la combinaison dans le cas des hybrides et adapt\u00e9es ult\u00e9rieurement pour traiter de l’aptitude \u00e0 l’association. Un mod\u00e8le statistique a \u00e9t\u00e9 d\u00e9velopp\u00e9 pour estimer les effets de comp\u00e9titions entre les g\u00e9notypes en plus de leur potentiel de production en culture pure. Ce travail m\u00e9thodologique s’appuie sur des exp\u00e9rimentations r\u00e9alis\u00e9es dans un dispositif en rangs altern\u00e9s ainsi qu’en culture pure. Il a permis de mettre en \u00e9vidence les variables refl\u00e9tant la comp\u00e9tition et d’identifier les g\u00e9notypes qui ont un comportement int\u00e9ressant en comp\u00e9tition.<\/p>\n Aur\u00e9lien Sagha\u00ef<\/strong><\/p>\n aurelien.saghai@u-psud.fr<\/p>\n ESE Laboratoire d’Ecologie; Syst\u00e9matique et Evolution – UMR CNRS 8079 Universit\u00e9 Paris-Sud. Btiment 360. 91405 Orsay CEDEX. FRANCE<\/p>\n <\/p>\n Metagenome-based diversity analyses suggest a significant contribution of non-cyanobacterial lineages to carbonate precipitation in modern microbialites<\/p>\n <\/p>\n Microbialites are organosedimentary structures whose formation is influenced by the metabolic activity of phylogenetically diverse microbial communities. Microbialites are today found in a restricted number of environments where the conditions (e.g. high alkalinity; saturation in specific elements) are favorable to the precipitation of minerals; notably carbonate. Cyanobacteria are thought to play a key role in carbonate precipitation due to their metabolic activity; but other organisms carrying out oxygenic photosynthesis (photosynthetic eukaryotes) or other metabolisms (e.g. anoxygenic photosynthesis; sulfate reduction); may also contribute to carbonate formation. We studied the microbial diversity of microbialites from the Alchichica crater lake (Mexico) by mining for 16S\/18S rRNA genes in metagenomes obtained by direct sequencing of environmental DNA. We studied samples collected at the Western (AL-W) and Northern (AL-N) shores of the lake and; at the latter site; along a depth gradient (1; 5; 10 and 15 m depth). The associated microbial communities were mainly composed of bacteria; whereas archaea were negligible. Eukaryotes composed a relatively minor fraction dominated by photosynthetic lineages. Although cyanobacteria were the most important bacterial group contributing to the carbonate precipitation potential; photosynthetic eukaryotes; anoxygenic photosynthesizers and sulfate reducers were also very abundant. Multivariate statistical analyses showed a strong positive correlation of two cyanobacterial groups (Pleurocapsales and Chroococcales) with aragonite formation at macroscale; suggesting a potential causal link. Despite the previous identification of intracellularly calcifying cyanobacteria in Alchichica microbialites; most carbonate precipitation seems extracellular in this system.<\/p>\n <\/p>\n Julien FUMEY<\/strong>, H\u00e9l\u00e8ne HINAUX, C\u00e9line NOIROT, Sylvie R\u00c9TAUX and Didier CASANE<\/p>\n <\/p>\n julien.fumey@universite-paris-saclay.fr<\/a><\/p>\n <\/p>\n Evolution G\u00e9nomes Comportement Ecologie B\u00e2timent 13 Avenue de la Terrasse 91198 Gif sur Yvette<\/p>\n <\/p>\n <\/p>\n Tempo and mode in Astyanax mexicanus <\/em>cavefish evolution : a population genomic reappraisal<\/p>\n <\/p>\n R\u00e9sum\u00e9. Les populations cavernicoles aveugles de Tetra du Mexique (Astyanax mexicanus<\/em>) sont d\u2019excellents mod\u00e8les pour \u00e9tudier l\u2019\u00e9volution. En effet, la convergence ph\u00e9notypique de populations qui ont \u00e9volu\u00e9es ind\u00e9pendamment pour s\u2019adapter \u00e0 un m\u00eame environnement cavernicole permet d\u2019\u00e9tudier si l\u2019\u00e9volution de ph\u00e9notypes similaires implique la fixation de variation g\u00e9n\u00e9tique pr\u00e9existante et\/ou de mutations de novo<\/em>.<\/p>\n Nous avons utilis\u00e9 une approche de g\u00e9nomique des populations afin d\u2019estimer le temps d\u2019\u00e9volution de la population cavernicole Pach\u00f3n, qui est consid\u00e9r\u00e9e comme \u00e9tant une des plus anciennes et des plus isol\u00e9es. Nous avons compar\u00e9s les taux de polymorphismes et de substitutions dans les transcriptomes de cette population et d\u2019une population de surface provenant du Texas et en utilisant le Tetra de Buenos Aires (Hyphessobrycon anisitsi<\/em>) comme groupe externe. Nous avons identifi\u00e9 un polymorphisme plus important dans les populations de surface ce qui sugg\u00e8rent, comme attendu, une plus grande taille efficace de cette population. Nous avons \u00e9galement identifi\u00e9 un plus grand taux de substitutions chez la population cavernicole, qui peut \u00e9galement s\u2019expliquer par sa taille r\u00e9duite permettant une fixation plus rapides des all\u00e8les d\u00e9riv\u00e9s pr\u00e9sent dans la population ancestrale. Mais ce r\u00e9sultat implique \u00e9galement que la population Pach\u00f3n est bien plus jeune qu\u2019estim\u00e9e jusqu\u2019alors. La comparaison de ces donn\u00e9es avec des simulations sugg\u00e8re que cette population serait apparue il y a moins de 30 000 ans. Ce nouveau cadre temporel ainsi que<\/p>\n d\u2019autres r\u00e9sultats indique que l\u2019\u00e9volution de ce ph\u00e9notype cavernicole implique principalement la fixation de variations pr\u00e9existantes dans les populations de surface, et ce dans une courte p\u00e9riode de temps.<\/p>\n <\/p>\n Abstract. Populations of blind cavefish belonging to the Mexican tetra species Astyanax mexicanus <\/em>are outstanding models to study evolution because the phenotypic convergence of independently-evolved and cave-adapted populations allows questioning whether the evolution of similar phenotypes involved the fixation of standing genetic variation and\/or de novo mutations. In order to estimate the time frame of the evolution of the Pach\u00f3n cave population which is considered as one of the \u201coldest\u201d and most isolated cave population, we applied a population genomics approach. We compared polymorphisms and substitution rates in the transcriptomes of Pach\u00f3n cavefish and surface fish from San Solomon Spring in Texas, using the Buenos Aires tetra (Hyphessobrycon anisitsi<\/em>) as an outgroup. The higher polymorphism in the surface population suggests, as expected, that its effective population size is larger. We found a higher substitution rate in cavefish than in surface fish, also in accordance with a smaller cavefish population size that allowed a more rapid fixation of derived alleles present in the ancestral population, but it implies that the Pach\u00f3n cave<\/p>\n population is much \u201cyounger\u201d than previously estimated. The comparison of these data with simulations suggests that this cavefish population has probably spent less than 30,000 years underground. This new time frame, together with other evidence, indicate that evolution of cave phenotypes mainly involved the fixation of cryptic genetic variants present in surface fish populations within a short period of time.<\/p>\n <\/p>\n Julie Borg<\/strong><\/p>\n julie.borg@moulon.inra.fr<\/p>\n G\u00e9n\u00e9tique Quantitative et Evolution-Le Moulon Ferme du Moulon 91190 Gif-sur-Yvette<\/p>\n <\/p>\n Wheatamix; int\u00e9r\u00eat des m\u00e9langes vari\u00e9taux de bl\u00e9 tendre dans le bassin parisien<\/p>\n <\/p>\n WHEATAMIX se focalise sur la c\u00e9r\u00e9ale la plus importante du Bassin parisien; le bl\u00e9; dans le but de mieux \u00e9valuer si la diversit\u00e9 g\u00e9n\u00e9tique intra-parcellaire permet de renforcer la multi-fonctionnalit\u00e9 et la r\u00e9silience des agro-\u00e9cosyst\u00e8mes; dans le contexte de changement global. Ce projet de recherche multi-disciplinaire \u00e9tudie l’impact de la diversit\u00e9 intra-sp\u00e9cifique sur la stabilit\u00e9 des rendements et autres services \u00e9cosyst\u00e9miques (r\u00e9gulation des maladies; fertilit\u00e9 des sols; conservation de la biodiversit\u00e9) rendus \u00e0 l’\u00e9chelle de la parcelle. L’analyse des liens entre groupes de services et les traits des vari\u00e9t\u00e9s; ainsi que l’\u00e9tude des compromis entre services permettra de comprendre l’impact de la diversit\u00e9 g\u00e9n\u00e9tique pilot\u00e9e sur le fonctionnement agro\u00e9cologique d’une parcelle; en int\u00e9grant la biodiversit\u00e9 sauvage associ\u00e9e.<\/p>\n Projet port\u00e9 par J\u00e9r\u00f4me Enjalbert.<\/p>\n <\/p>\n <\/p>\n <\/p>\n <\/p>\n H\u00e9l\u00e8ne Badouin, Michael E Hood, J\u00e9r\u00f4me Gouzy , Eric Fontanillas, Gabriela Aguileta, Sophie Siguenza, Michael H Perlin, Christina A Cuomo, C\u00e9cile Fairhead, Antoine Branca, Tatiana Giraud<\/strong><\/p>\n <\/p>\n\n