0000000000562908
AUTHOR
Florence Deau
Soil microbial diversity effects on primary production and symbiotic interactions
SPEEAEcolDurGenoSolGEAPSI; The importance of telluric microorganisms linked together by trophic exchanges with plants, that sustain all ecosystems through primary production, is known. However, the role of soil microbial diversity for primary production remains controversial. A diversity decreasing was achieved, by inoculating a sterilized soil with serial dilutions of a suspension from the same non-sterilized soil, to determine the consequences of microbial diversity erosion on the growth and fitness of three plant species more or less dependent on symbionts, Medicago truncatula, Brachypodium distachyon and Arabidopsis thaliana. The results showed that the impact of microbial diversity dec…
Shotgun metagenomics sequencing of the rhizosphere microbiota associated to seven ecotypes of Medicago truncatula
International audience; Healthy plants host a remarkable diversity of microorganisms known as plant microbiota, which provide host services such as pathogen protection and nutrient acquisition. Thus, plant microbiota emerges as a trait that extends the capacity of plants to adapt to their environment. So far, microbial community profiling has mostly allowed the description of the phylogenetic structure of plant microbiota, whereas functional insights were mostly obtained from experiments using model strains. Thus, the plant impact on the microbial functional genes pool in the rhizosphere remains largely unknown. The goals of the study were to (i) compare the functional genes pool of the rhi…
Legacy effects of contrasting water and N-availability patterns on plantmicrobial response to rewetting
National audience; Introduction. Shifts in the frequency and magnitude of rain events (precipitation regime) associated with climate change may affect plant morphological and physiological strategies as well as soil microbial activity.Objectives. The objective of this study was to determine i) how precipitation history shapes the response dynamics of soil bacterial and fungal communities to rewetting, as well as plant-microbial competition for N, and ii) how the N status of the system may modulate the effect of precipitation regime.Materials & methods. The legacy effects of 12 weeks of contrasting precipitation (frequent or infrequent watering, equal total water input) and N inputs was asse…
Rhizosphere Bacterial Networks, but Not Diversity, Are Impacted by Pea-Wheat Intercropping
International audience; Plant-plant associations, notably cereal-legume intercropping, have been proposed in agroecology to better value resources and thus reduce the use of chemical inputs in agriculture. Wheat-pea intercropping allows to decreasing the use of nitrogen fertilization through ecological processes such as niche complementarity and facilitation. Rhizosphere microbial communities may account for these processes, since they play a major role in biogeochemical cycles and impact plant nutrition. Still, knowledge on the effect of intecropping on the rhizosphere microbiota remains scarce. Especially, it is an open question whether rhizosphere microbial communities in cereal-legume i…
Variable and core functional microbiota associated with seven Medicago truncatula genotypes
The rhizosphere microbiota emerges as a novel component that expands plant adaptation to its environment, and thus paves the way for future breeding approaches. Knowledge regarding the "functional core microbiota", which refers to the microbial taxa bearing essential functions for holobiont fitness, is required to move forward in this area. The aim of the present study was to compare the functional microbiota recruited by different plant genotypes in order to identify itscore and variable components. Seven genotypes of Medicago truncatula (DZA315-16, DZA315-26, DZA045-6, F83005-5, SA028064, Jemalong A17 and J6), representatives of a core collection of 184 genotypes, were studied. Functional…
Effects of precipitation regime and N-availability on the dynamics of plant-microbial and soil biogeochemical cycling responses to rewetting
International audience; Introduction. Shifts in the frequency and magnitude of rain events (precipitation regime) associated with climate change may affect plant morphological and physiological strategies as well as soil microbial activity. Objectives. The objective of this study was to determine i) how precipitation history shapes the response dynamics of soil bacterial and fungal communities to rewetting, as well as plant-microbial competition for N, and ii) how the N status of the system may modulate the effect of precipitation regime. Materials & methods. The legacy effects of 12 weeks of contrasting precipitation (frequent or infrequent watering, equal total water input) and N inputs w…