Search results for "MEDICAGO"
showing 10 items of 107 documents
Endosperm cintribution to Medicago truncatula seed development : characterization of a DOF transcription factor expressed in chalazal endosperm
2014
In the current context, which necessitates a reduction in inputs in crop systems and boosting of production of plant proteins to reduce France’s dependency on feed imports,, growing legumes represents an alternative. Grain legumes are major sources of proteins for animal and human nutrition. In the UMR1347 Agroécologie, the objectives of the study group "déterminismes Génétiques et Environnementaux de l’Adaptation des Plantes à des Systèmes de culture Innovants" (GEAPSI) are to promote legume cultivation and adaptation to environmental stresses, via multidisciplinary approaches (genetics, ecophysiology, molecular physiology). This thesis project was carried out in the "Étude des Mécanismes …
Medicago truncatula
2012
In plants, long distance transport of sugars from photosynthetic source leaves to sink organs comprises different crucial steps depending on the species and organ types. Sucrose, the main carbohydrate for long distance transport is synthesized in the mesophyll and then loaded into the phloem. After long distance transport through the phloem vessels, sucrose is finally unloaded towards sink organs. Alternatively, sugar can also be transferred to non‐plant sinks and plant colonization by heterotrophic organisms increases the sink strength and creates an additional sugar demand for the host plant. These sugar fluxes are coordinated by transport systems. Main sugar transporters in plants compri…
The underlying processes governing seed size plasticity: Impact of endoploidy on seed coat development and cell expansion in Medicago truncatula
2019
Prod 2019-55a BAP GEAPSI CT1 BAP; Abstract Bigger seeds represent an agronomic and economic benefit but the breeding and ecological balance between seed size and number is difficult to find. Large seeds associated with other practices can improve crop competitiveness as they are more vigorous and result in healthier crops with higher yields, even under stressful conditions. Applying genomic research and genome-wide association studies to breeding is generating new strategies to improve seed traits and novel insights into the biology of seed development and metabolism that are discussed in this chapter. The DNA amount differs among the seed tissues and amplifying genomic DNA by endocycle ind…
Medicago species affect the community composition of arbuscular mycorrhizal fungi associated with roots
2007
National audience; The symbiosis between plants and arbuscular mycorrhizal fungi (AMF) is ancient and involves 80% of terrestrial plant families. The symbiotic association between AMF and plants was described to be non specific. However, AMF were reported to influence plant community diversity and productivity. On the other way, the effect of plant genotypes belonging to closely related species on AMF diversity has not been explored so far. The aim of this work was to assess the impact of four different Medicago species, M. laciniata, M. murex, M. polymorpha and M. truncatula cv. Jemalong J5, on the composition of AM fungal community, when cultivated in a silty-thin clay soil (Mas d’Imbert,…
Combining ecophysiological and microbial ecological approaches to assess interaction between genotypes of Medicago truncatula and the soil bacterial …
2011
International audience; Microbial communities can play a key role in sustainable agriculture by improving crop growth. Currently, a major stake is to study the effect of the plant genotype on the shaping of the soil microbial communities in relation to the plant nutrition. Methods: The links between the plant genotype and the rhizospheric bacterial communities were assessed at both structural and functional level using a multidisciplinary approach. On the one side, the genetic structure (Automated Ribosomial Intergenic Spacer Analysis (ARISA)) and diversity (454 pyrosequencing) of bacterial communities of the rhizosphere was first analysed. On the other side, using an ecophysiological model…
Influence of type III bacterial secretion system on the interactions between plant and non pathogenic fluorescent Pseudomonads spp.
2010
No abstract
Shotgun metagenomics sequencing of the rhizosphere microbiota associated to seven ecotypes of Medicago truncatula
2019
International audience; Healthy plants host a remarkable diversity of microorganisms known as plant microbiota, which provide host services such as pathogen protection and nutrient acquisition. Thus, plant microbiota emerges as a trait that extends the capacity of plants to adapt to their environment. So far, microbial community profiling has mostly allowed the description of the phylogenetic structure of plant microbiota, whereas functional insights were mostly obtained from experiments using model strains. Thus, the plant impact on the microbial functional genes pool in the rhizosphere remains largely unknown. The goals of the study were to (i) compare the functional genes pool of the rhi…
The Medicago truncatula hypermycorrhizal B9 mutant displays an altered response to phosphate and is more susceptible to Aphanomyces euteiches.
2014
SPE IPM; National audience; Inorganic phosphate (Pi) plays a key role in the development of arbuscular mycorrhizal (AM) symbiosis, which is favoured when Pi is limiting in the environment. We have characterized the Medicago truncatula hypermycorrhizal B9 mutant for its response to limiting (P/10) and replete (P2) Pi. On P2, mycorrhization was significantly higher in B9 plants than in wild-type (WT). The B9 mutant displayed hallmarks of Pi-limited plants, including higher levels of anthocyanins and lower concentrations of Pi in shoots than WT plants. Transcriptome analyses of roots of WT and B9 plants cultivated on P2 or on P/10 confirmed the Pi-limited profile of the mutant on P2 and highli…
Transcriptional response of Medicago truncatula sulphate transporters to arbuscular mycorrhizal symbiosis with and without sulphur stress
2013
Sulphur is an essential macronutrient for plant growth, development and response to various abiotic and biotic stresses due to its key role in the biosynthesis of many S-containing compounds. Sulphate represents a very small portion of soil S pull and it is the only form that plant roots can uptake and mobilize through H(+)-dependent co-transport processes implying sulphate transporters. Unlike the other organically bound forms of S, sulphate is normally leached from soils due to its solubility in water, thus reducing its availability to plants. Although our knowledge of plant sulphate transporters has been growing significantly in the past decades, little is still known about the effect of…
Use of translational genomics to identify genes important for legume seed development
2015
BAP Pôle GEAPSI; International audience; We have exploited the extensive synteny between the model legume Medicago truncatula and the cultivated garden pea, Pisumsativum, to identify loci controlling seed filling and seedcomposition in the crop species. QTLs for these traits are mapped by analyzing variation with in collections of recombinant inbred lines. Candidate genes with in the QTL intervals are identified by reference to the M.truncatula genomic sequence. This approach was used to uncover an endosperm subtilase that is associated with syntenic seed weight QTLs in Medicago and pea, and we discuss the possible role played by this enzyme in contributing to final seed weight.