Local and systemic mycorrhiza-induced protection against the ectoparasitic nematode Xiphinema index involves priming of defence gene responses in grapevine

International audience; The ectoparasitic dagger nematode (Xiphinema index), vector of Grapevine fanleaf virus (GFLV), provokes gall formation and can cause severe damage to the root system of grapevines. Mycorrhiza formation by Glomus (syn. Rhizophagus) intraradices BEG141 reduced both gall formation on roots of the grapevine rootstock SO4 (Vitis berlandierixV. riparia) and nematode number in the surrounding soil. Suppressive effects increased with time and were greater when the nematode was post-inoculated rather than co-inoculated with the arbuscular mycorrhizal (AM) fungus. Using a split-root system, decreased X. index development was shown in mycorrhizal and non-mycorrhizal parts of my…

Sugar exchanges in arbuscular mycorrhiza: RiMST5 and RiMST6, two novel Rhizophagus irregularis monosaccharide transporters, are involved in both sugar uptake from the soil and from the plant partner

SPE IPM INRA UB CT1; International audience; Arbuscular mycorrhizal (AM) fungi are associated with about 80% of land plants. AM fungi provide inorganic nutrients to plants and in return up to 20% of the plant-fixed CO2 is transferred to the fungal symbionts. Since AM fungi are obligate biotrophs, unraveling how sugars are provided to the fungus partner is a key for understanding the functioning of the symbiosis. In this study, we identified two new monosaccharide transporters from Rhizophagus irregularis (RiMST5 and RiMST6) that we characterized as functional high affinity monosaccharide transporters. RiMST6 was characterized as a glucose specific, high affinity H(+) co-transporter. We prov…

Medicago truncatula gene responses specific to arbuscular mycorrhiza interactions

International audience

Impact of tillage system on arbuscular mycorrhiza fungal communities in the soil under Mediterranean conditions.

A more diverse arbuscular mycorrhiza (AM) fungal community should be more versatile and resilient to variation in environmental conditions over space and time. To evaluate the effect of no-till and conventional tillage systems, AM fungal diversity was assessed as part of a long term field experiment by sequencing of DNA, extracted from soil, that encoded the large ribosomal sub-unit and was obtained by nested-PCR. In comparison with no-till, conventional tillage decreased AM fungal diversity by 40%. Differences between treatments in the frequency of the operational taxonomic units (OTUs) present in soil, confirm that AM fungi are differently vulnerable to soil disturbance.

The role of the plant genome in modulating arbuscular mycorrhizal formation.

International audience

Role of a transcription factor, GintSTE, from Glomus intraradices in the establishment of arbuscular mycorrhizal

International audience

Participation à la fête de la nature et de la biodiversité au Jardin des Sciences du Parc de l’Arquebuse à Dijon le dimanche 21 mai 2017

Symbiose ou pathogenèse? Quels peuvent être les mécanismes moléculaires déterminants?

National audience

Do crop genotypes have residual effects on Glomeromycota communities in agro-systems

International audience

An STE12 gene identified in the mycorrhizal fungus Glomus intraradices restores infectivity of a hemibiotrophic plant pathogen

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 …

Expression profiling of up-regulated plant and fungal genes in early and late stages of Medicago truncatula - Glomus mosseae interactions

International audience

Dynamics of sugar transports in tobacco-microbe interactions

Gènes activés lors de l'interaction racine / Glomus mosseae chez Medicago truncatula

National audience

Sugar exchanges in arbuscular mycorrhiza : Characterization and role of two new monosaccharide transporters from the model fungus Rhizophagus irregularis

Identification of genes activated during arbuscular mycorrhiza interactions by suppressive substractive hybridisation and cloning of differential expresed cDNA

International audience

Rôle du facteur de transcription fongique GintSTE dans l’établissement de la symbiose mycorhizienne à arbuscules

National audience

25S rDNA-based molecular monitoring of glomalean fungi in sewage sludge-treated field plots

Recycling of sewage wastes in agriculture is likely to affect the biological activity of soils through contamination of ecosystems by pathogens and metallic or organic micropollutants. The impact of sewage sludge spreading under field conditions on arbuscular mycorrhiza (AM) formation by a community of glomalean fungi was evaluated using a nested polymerase chain reaction (PCR) and discriminating primers based on 25S rDNA polymorphisms to detect different fungal species within root systems. Medicago truncatula was grown in soil of field plots amended or not with a composted sewage sludge, spiked or not with organic or metallic micropollutants. Overall AM development in roots decreased with …

The use of genomic repeated sequences to characterize arbuscular mycorrhizal fungi

International audience

Changes in the glomeromycota community in soils treated with a mix of pesticides

International audience

Evaluation moléculaire in planta de la diversité des champignons mycorhizogènes dans des champs amendés avec des boues d'épuration

National audience