Search results for "SYMBIOSIS"
showing 10 items of 627 documents
La pollinisation du cassis : État des lieux dans un contexte de changements anthropiques.
2019
Cultivated plants are part of their agroecosystem. Recent anthropic changes modified and decreased the wildcompartment of agroecosystems leading to a lowering of ecosystemic services such as pollination. Blackcurrant ispollinated at least partially by insects. In a study on 8 sites in Côte-d’Or, Burgundy, France we showed that pollinatordensity is lower than 0.5 pollinators per minute of observation in blackcurrant orchards. Blackcurrant are preferentiallyvisited by Bombus sp. and to a lesser extent by Andrena and Apis sp. Comparison of pollinator abundance between2018 data and data from ancient publications show that even if the floral abortion rate did not vary significantly, thenumber of…
The membrane proteome of Medicago truncatula roots displays qualitative and quantitative changes in response to arbuscular mycorrhizal symbiosis
2014
International audience; Arbuscular mycorrhizal (AM) symbiosis that associates roots of most land plants with soil-borne fungi (Glomeromycota), is characterized by reciprocal nutritional benefits. Fungal colonization of plant roots induces massive changes in cortical cells where the fungus differentiates an arbuscule, which drives proliferation of the plasma membrane. Despite the recognized importance of membrane proteins in sustaining AM symbiosis, the root microsomal proteome elicited upon mycorrhiza still remains to be explored. In this study, we first examined the qualitative composition of the root membrane proteome of Medicago truncatula after microsome enrichment and subsequent in dep…
Identification of Traits Implicated in the Rhizosphere Competence of Fluorescent Pseudomonads: Description of a Strategy Based on Population and Mode…
2009
E-book; International audience; The lack of consistency of the beneficial effects of inoculated fluorescent pseudomonads has often been related to their bad survival in the rhizosphere. In this review, we describe the strategy followed over the last decade to study traits involved in the rhizosphere competence of these bacteria. The diversity of indigenous populations associated with plant roots was first compared to that of populations associated with uncultivated soils in order to identify traits that discriminate these populations. The involvement of these bacterial traits in the rhizosphere competence was then assessed by comparing the competitiveness of a wild-type strain to that of mu…
Characterization of Pea (Pisum Sativum L.) genes implicated in arbuscular mycorrhiza formation and function
2010
The arbuscular mycorrhizal (AM) association results from a successful interaction between the genomes of the two symbiotic partners. In this context, the aim of my research was to better characterize the role of the late stage symbiosis-related pea genes PsSym36, PsSym33 and PsSym40 in the functional AM (i) by investigating the effect of mutations in the three genes on fungal and plant gene responses and (ii) by creating conditions for the localization of two of the genes, PsSym36 and PsSym40, on the pea genetic map for future map-based cloning. The expression of a subset of ten fungal and eight plant genes,previously reported to be activated during mycorrhiza development, was compared in G…
Grape cultivar affects larval and female fitness of the European grapevine moth, Lobesia botrana (Lepidoptera: Tortricidae)
2005
8 pages; International audience
The arbuscular mycorrhizal symbiosis a modulator of cadmium stress
2008
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, such as 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 quantif…
Could subcellular proteomics of root plastids teach us more about mycorrhizal symbiosis?
2007
International audience; The arbuscular mycorrhizal (AM) symbiosis is a mutualistic association between soil-borne fungi and the roots of most plant species. Involving the bilateral exchange of nutrients, the symbiosis is connected to drastic changes in plant cell organelle morphology and physiology. Root plastids, in particular, are forming extensive, network-like structures covering the main symbiotic interface, i.e., intracellular, highly branched haustorium-like fungal structures called arbuscules. These plastid networks are highly dynamic and are formed and degraded concomitantly with the formation and degradation of arbuscules. By producing basic metabolic building blocks like fatty ac…
Genes encoding transcription factors in Glomus intraradices and their expression at the appressoria stage of arbuscular mycorrhiza interactions
2007
International audience; Molecular pathways governing the life cycle of arbuscular mycorrhizal (AM) fungi and their symbiotic interactions with root tissues are not yet fully understood. Most studies fo fungal responses to host plants have targeted developmental stages before root contact (germinating spores), or after root colonization (intraradical mycelium). We are focusing on the early cell events of appressoria contact with the root surface which are essential to the successful outcome of the AM symbiosis. Recent monitoring of Glomus intraradices gene expression at this stage has revealed differential fungal responses to roots of host and non-host (Myc- mutants) M. truncatula (Seddas et…
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…
Free-living plant-beneficial microorganisms and soil quality.
2005
CABI Publishing, Wallingford Oxon, UK,