Biology subjects

Philippot, L.

Publications and source records attributed to Philippot, L..

3 recordsLinked to original sources

bioRxiv2025

Diverse crop rotations off-set yield-scaled nitrogen losses via denitrification

Denitrification, a major source of gaseous nitrogen (N) emissions from agricultural soils, is influenced by management. Practices promoting belowground diversity are suggested to support sustainable agriculture, but their ability to modulate gaseous N-losses via denitrification remains inconclusive. To fill this knowledge gap, we sampled 106 cereal fields spanning a 3,000 km North-South gradient across Europe and compiled 56 associated climatic, soil, microbial and management variables. We found that increased denitrification was associated with higher proportion of time with crop cover over the last ten years. Denitrification rates were best predicted by microbial biomass and microbial functional guilds involved in N cycling, in particular denitrification. We also show that several diversification practices affect the variation in denitrification predictors, suggesting a trade-off between agricultural diversification and gaseous N-losses via denitrification. However, increased crop diversity in rotations improved yield-scaled denitrification, highlighting the potential of this practice to minimize N losses while contributing to sustainable food production.

ecology↗

bioRxiv2021

Artificial selection of stable rhizosphere microbiota leads to heritable plant phenotype changes

Research on artificial selection of microbial community has become popular due to perspectives in improving plant and animal health1-4. However, reported results still lack consistency5-8. We hypothesized that artificial selection may provide desired outcomes provided that microbial community structure has stabilized along the selection process. In a ten-generation artificial selection experiment involving 1,800 plants, we selected rhizosphere microbiota of Brachypodium distachyon that were associated with high or low levels of leaf greenness, a proxy for plant health9. Monitoring of the rhizosphere microbiota dynamics showed strong oscillations in community structure during an initial transitory phase of five generations, with no heritability in the selected property. In the last five generations, the structure of microbial communities displayed signs of stabilization, concomitantly to the appearance of heritability in leaf greenness. Selection pressure, initially ineffective, became successful in changing the greenness index in the intended direction, especially toward high greenness values. We showed a remarkable congruence between plant traits and selected microbial community structures, highlighting two phylogenetically distinct microbial sub-communities correlating with leaf greenness, whose abundance was significantly steered by directional artificial selection. Understanding microbial community structure stabilization can thus help improve the reliability of artificial microbiota selection. Short SentenceStable microbiota selection enables trait heritability

evolutionary biology↗

bioRxiv2019

A core microbiota of the plant-earthworm interaction conserved across soils

Microorganisms participate in most crucial soil functions and services benefiting human activities, such as biogeochemical cycles, bioremediation and food production. Their activity happens essentially in hotspots created by major soil macroorganisms, like rhizosphere and cast shaped by plants and earthworms respectively1. While effects of individual macroorganism on soil microbes are documented, no studies attempted to decipher how the mosaic of microhabitats built by multiple macroorganisms and their interaction determine the structure of microbial communities. Here we show a joint shaping of soil bacterial communities by these two macroorganisms, with a prevalent role of plants over earthworms. In a controlled microcosm experiment with three contrasted soils and meticulous microhabitat sampling, we found that the simultaneous presence of barley and endogeic earthworms resulted in non-additive effects on cast and rhizosphere bacterial communities. Using a source-sink approach derived from the meta-community theory2,3, we found specific cast and rhizosphere core microbiota4,5 of the plant-eartworm interaction, detected in all soils only when both macroorganisms are present. We also evidenced a core network of the plant-earthworm interaction, with cosmopolitan OTUs correlated both in cast and rhizosphere of all soils. Our study provides a new framework to explore aboveground-belowground interactions through the prism of microbial communities. This multiple-macroorganisms shaping of bacterial communities also affects fungi and archaea, while being strongly influenced by soil type. Further functional investigations are needed to understand how these core microbiota and core network contribute to the modulation of plant adaptive response to local abiotic and biotic conditions.

ecology↗