Search results for "ARBUSCULAR MYCORRHIZAL"
showing 10 items of 90 documents
Importance of dispersal and thermal environment for mycorrhizal communities: lessons from Yellowstone National Park
2011
International audience; The relative importance of dispersal and niche restrictions remains a controversial topic in community ecology, especially for microorganisms that are often assumed to be ubiquitous. We investigated the impact of these factors for the community assembly of the root-symbiont arbuscular mycorrhizal fungi (AMF) by sampling roots from geothermal and nonthermal grasslands in Yellowstone National Park (YNP), followed by sequencing and RFLP of AMF ribosomal DNA. With the exception of an apparent generalist RFLP type closely related to Glomus intraradices, a distance-based redundancy analysis indicated that the AMF community composition correlated with soil pH or pH-driven c…
Arbuscular mycorrhizal fungi, partners of the rhizostabilization process of an orphan mining site
2012
International audience
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…
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,…
Effect of rhizosphère bacteria and endomycorrhizal fungi on the growth of Christmas rose (Helleborus niger L.)
2010
International audience; Micropropagated and vegetative (by rhizome cuttings) propagated plants of Christmas rose ( Helleborus niger L.) were tested for their responses to the inoculation with microorganisms in order to optimize root growth and development. In our experiment, plants were inoculated with arbuscular endomycorrhizal fungi or/and Agrobacterium radiobacter . The investigation indicated that inoculation with A. radiobacter had significantly positive effect on growth and development of plants multiplicated by in vitro techniques as compared to the dual inoculation. This study indicates that, biotization can be beneficial to plant growth in in vitro plant production systems but inoc…
Soil Nutrient and Water providers: How Arbuscular Mycorrhizal Mycelia Support Plant Performance in a Resource-Limited World
2007
International audience
Towards a cell-specific expression atlas of arbuscular mycorrhizal roots in the model legume Medicago truncatula
2007
International audience
Effect of cadmium on growth, isoflavonoid and protein accumulation patterns in mycorrhizal roots of Medicago truncatula
2007
International audience; Ecosystems are submitted to various abiotic stresses, among which heavy metals represent major industrial pollutants. Cadmium (Cd), that has damaging effects on plant metabolism, occurs in agricultural environments through industrial pollution and human activities, including phosphate fertiliser and sewage sludge applications. Metal availability to plants can be modulated by soil microorganisms, including arbuscular mycorrhizal (AM) fungi. In the present work, Cd effects on the model legume Medicago truncatula inoculated or not with the AM fungus Glomus intraradices have been studied at 3 levels: (1) plant biomass production together with green part chlorophyll quant…
Contribution of proteomics to arbuscular mycorrhiza in Medicago truncatula
2007
International audience; Because proteins are key effectors of plant responses to environmental cues including recognition, signalling, transport and defence reactions, main interest has been paid to characterize those involved in the establishment and functioning of arbuscular mycorrhizal (AM) symbiosis. In our group, the setting up of high throughput proteomic techniques on the model species, Medicago truncatula, is providing step-by-step a large-scale analysis of AM symbiosis-related proteins. Depending on the symbiotic stage targeted and on the abundance of mycorrhizal material, different proteomic strategies that can be combined with other large-scale approaches (transcriptomic and meta…
Interactions between a mycorrhiza helper bacterium and arbuscular mycorrhizas
2009
Pseudomonas fluorescens C7R12 was shown to promote arbuscular mycorrhization and to act as a ‘Mycorrhiza Helper Bacteria’ (MHB). The complex interactions between this model strain, Arbuscular Mycorrhizal (AM) fungi and host-plants were analysed by assessing the specificity of these interactions and by characterizing bacterial cell organization on mycorrhizal roots. Evaluation of the interaction specificity relied on the comparison of the bacterial effect on (i) the in vitro saprophytic growth of Glomus mosseae and Gigasopora rosea and (ii) the root colonization of two different plant species (Medicago truncatula and Lycopersicon esculentum) by the two AM fungal species. Characterization of …