Search results for "mycorhizes"
showing 10 items of 17 documents
Spatial monitoring of gene activity in extraradical and intraradical developmental stages of arbuscular mycorrhizal fungi by direct fluorescent in si…
2008
International audience; Gene expression profiling based on tissue extracts gives only limited information about genes associated with complex developmental processes such as those implicated in fungal interactions with plant roots during arbuscular mycorrhiza development and function. To overcome this drawback, a direct fluorescent in situ RT-PCR methodology was developed for spatial mapping of gene expression in different presymbiotic and symbiotic structures of an arbuscular mycorrhizal fungus. Transcript detection was optimized by targeting the LSU rRNA gene of Glomus intraradices and monitoring expression of a stearoyl-CoA-desaturase gene that is consistently expressed at high levels in…
An STE12 gene identified in the mycorrhizal fungus Glomus intraradices restores infectivity of a hemibiotrophic plant pathogen
2009
International audience; * • Mechanisms of root penetration by arbuscular mycorrhizal (AM) fungi are unknown and investigations are hampered by the lack of transformation systems for these unculturable obligate biotrophs. Early steps of host infection by hemibiotrophic fungal phytopathogens, sharing common features with those of AM fungal colonization, depend on the transcription factor STE12. * • Using degenerated primers and rapid amplification of cDNA ends, we isolated the full-length cDNA of an STE12-like gene, GintSTE, from Glomus intraradices and profiled GintSTE expression by real-time and in situ RT-PCR. GintSTE activity and function were investigated by heterologous complementation …
Regional-scale analysis of arbuscular mycorrhizal fungi: the case of Burgundy vineyards
2016
SPE IPM INRA UB; Aim : To improve knowledge of arbuscular fungal communities for a sustainable management in vineyards. Methods and results : In 16 plots across Burgundy under contrasted soil properties and agricultural practices, we assessed arbuscular mycorrhizal fungal (AMF) diversity in vine roots, using pyrosequencing of ribosomal Internal Transcribed Spacers (ITS). AMF sequences could be retrieved from all plots across Burgundy, both in organic and in conventional vineyards with high chemical inputs. Sequences from the survey were almost exclusively affiliated to molecular taxa in the Glomerales, including six “core species” found in all plots, corresponding to 77% of all sequences, s…
Conférence invitée : " Mécanismes et gestion de la symbiose mycorhizienne dans les agro-écosystèmes"
2017
National audience; Présentations et échanges sur les résultats de l’INRA à propos desmycorhizes : quelles stratégies développées par les plantes pour mieuxutiliser les ressources naturelles du sol ? Comment favoriser desconditions favorables à l'installation et à la vie des champignonsbénéfiques du sol ? Quelle influence la nature du sol a-t’elle sur laquantité et la diversité de champignons mycorhiziens ? Quid desintrants ? Les fongicides ont-ils vraiment un effet délétère sur leschampignons Mycorhiziens ? La résistance des plantes aux pesticidespeut-elle être favorisée par les mycorhizes ?
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…
Les mycorhizes, une alliance plante-champignon découverte en 1885 et encore mal connue?
2017
Il y a 450 millions d’années, les plantes ont colonisé le milieu terrestre. Pour cela, elles se sont associées notamment avec des microbes du sol. La symbiose la plus répandue dans le monde végétal est la mycorhize (mûkes/champignon et rhiza/racine), formée entre les racines et des champignons microscopiques du sol, les Gloméromycètes. Cette symbiose a été décrite pour la première fois en 1885 par le botaniste allemand Albert FRANK. Ces champignons sont, pour les plantes, des alliés fantastiques. Ils facilitent l’absorption des éléments minéraux du sol et stimulent leurs défenses pour mieux résister aux maladies et plus largement aux stress (pollution, manque d’eau). Après la seconde guerre…
Mycorhizes à arbuscules : le transportome biotrophe de la cellule au champ
2017
Understanding mechanisms underlying high nutrients use efficiency and carbon allocation in a context of mycorrhizal interactions is critical for sound management of croplands taking care of ecosystem services rendered by mycorrhizal fungi. Transport processes across the polarised membrane interfaces are of major importance in the functioning of the established mycorrhizal association as the symbiotic relation is based on a 'fair-trade' between fungus and host plant. Uptake and exchanges of nutrient and/or metabolites, at biotrophic interfaces are controlled by membrane transporters and their regulation patterns are essential in determining the outcome of plant fungal interactions and in ada…
Caracterisation for ancient wheat varieties for their ability to form mycorrhiza and grain quality impact
2014
Wheat (kind Tritucum aestivum, Poaceae family) is a very important cereal ofagronomic interest. Some very ancient varieties are set aside for recent varieties often selected to meet a consumer intensive cultivation of pesticides. Organic farming production system assuming a reduction of synthetic chemical inputs in order to preserve the ecosystem can be defined as a practice where the use of synthetic fertilizers, chemical pesticides and genetically modified organisms is prohibited. This practice is gaining more and more popularity and the amount of land cultivated in this way has increased by 60% between 2000 and 2004. Constraints associated with the production of organic grains include lo…
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…
The contribution of model legumes to arbuscular mycorrhiza research
2009
International audience