Equipe IMR

Understanding the root microbiota that supports plant growth, health and nutritional quality, to help develop innovative cropping systems that capitalize on plant-microbiota interactions to limit inputs and promote yield and quality of productions.

Animation : Sylvie Mazurier

Composition : 2 scientists (Barbara Pivato, Sylvie Mazurier), 1 lecturer from uB (Jean-Paul Lemaitre), 1 engineer (Laure Avoscan), 1 technician on call (Florence Deau), 1 technician on fixed-term contract (Pierre-Manuel Loria), 2 PhDs (Amélie Semblat, Liya Zhu).

Study of bacterial communities and isolated strains

Bacterial communities studied using DNA/RNA extracted from rhizospheric soil and roots, and microorganisms isolated, cultivated and inoculated into plants (microscopy studies, bioassays in vitro, in the greenhouse, in the field). Study of different genera and species; there’s a particular focus on Pseudomonas bacteria (taxonomic and functional characterization).

From field to molecule … →

←…and molecule to field

•Study of microbial traits (synthesis of molecules chelating iron -siderophores- and/or other metals -metallophores-; ability to mobilize iron, phosphate, sulfur; synthesis of antibiotics; presence of secretory systems...) ...) and mechanisms involved in beneficial effects on the plant  (supply of iron, phosphate, sulfur and other micronutrients; promotion of biological fixation of atmospheric nitrogen; resistance to stress; antagonism against phytopathogens; stimulation of defense reactions...) and research into markers to identify and monitor the fate of beneficial microorganisms in soils and in association with the plant.

•Research into plant traits that favor the presence and activity of beneficial microorganisms, to identify varieties and plant associations (cereal-legume, such as wheat-pea) that make the most of the microbiota. Search for marker genes enabling plant traits favorable to beneficial interactions to be included in crop selection and genetic improvement programs.

Strategy

❶ Study the diversity and structure of microbial populations and communities involved in functions of interest Ø raise hypotheses

❷ Test hypotheses; identify traits and genes of interest in models (plants/microbial strains)

❸ Develop molecular tools enabling analysis of corresponding functional communities in return.

❹ Use these tools to study environmental factors that impact their functioning: Soils & cultivation practices; particular focus on pea-wheat intercropping, biotic (phytopathogenic) and abiotic (iron and water stress) stresses.

Collection

>15,000 bacterial strains from different soils and plants - flax, tomato, tobacco, medicago, wheat, peas...

>11,000 belong to various genera and species

>4,000 belong to the genus Pseudomonas

Representative projects

-EFfORT project - Carnot Institute Plant2Pro (2023-2025) - Ecology and Functioning of the Rhizospheric micrObiota involved in improving iron nuTrition in pea.

AMETHYSTES project - ANR - (2022-2025) Advanced characterization of microbial metallophores (molecules chelating iron and other metals) in soil-microorganism-plant environmental systems, effects on plant nutrition. https://anr.fr/Projet-ANR-21-CE20-0022

-POSiTiF project - Carnot Institute Plant2Pro (2018-2021) - Promoting pea tolerance to abiotic (Iron) and biotic (phytopathogenic) stress via biotic interactions in the rhizosphere. [POSiTiF project sheet]

•Articles scientifiques - Rhizosphere Bacterial Networks, but Not Diversity, Are Impacted by Pea-Wheat Intercropping (2021) https://doi.org/10.3389/fmicb.2021.674556  ; Impact of Bacterial Siderophores on Iron Status and Ionome in Pea (2020) https://doi.org/10.3389/fpls.2020.00730

•Revue scientifique - Importance of the rhizosphere microbiota on iron biofortification of plants (2021) https://doi.org/10.3389/fpls.2021.744445

•Article non académique - Compréhension et valorisation des interactions entre plantes et microorganismes telluriques : un enjeu majeur en Agroécologie ; ‘Le sélectionneur Français’ (2019) https://www.selectionneurs.asso.fr/wp-content/uploads/2019/12/BULL70-2019-07-P_Lemanceau_coll.-V04.pdf