Options
Mulot, Matthieu
Nom
Mulot, Matthieu
Affiliation principale
Fonction
Ancien.ne collaborateur.trice
Identifiants
Résultat de la recherche
Voici les éléments 1 - 10 sur 10
- PublicationAccès libreAssessing the responses of Sphagnum micro-eukaryotes to climate changes using high throughput sequencing(2020-9-18)
; ; ; - PublicationAccès libreA worldwide survey of neonicotinoids in honey(2017-9-6)
; ; - PublicationMétadonnées seulementEffects of decomposing cadavers on soil nematode communities over a one-year period(2016-12-1)
; ; ; ; - PublicationAccès libreBio-inoculation of yerba mate seedlings (Ilex paraguariensis St. Hill.) with native plant growth-promoting rhizobacteria: a sustainable alternative to improve crop yield
; ; ; ; In this study, the role of native plant growth-promoting rhizobacteria (PGPR) as bio-inoculants was assessed as an alternative to ameliorate Ilex paraguariensis St. Hill. growth in nursery comparing poorer (soil) versus richer (compost) substrates. Twelve rhizospheric strains isolated from yerba mate plantations were evaluated in vitro for their potential as PGPRs. Three isolates, identified as Kosakonia radicincitans YD4, Rhizobium pusense YP3, and Pseudomonas putida YP2, were selected on the basis of their N2 fixation activity, IAA-like compound and siderophore production, and phosphate solubilization. A highly significant positive effect of bio-inoculation with the native isolates was observed in 5-month-old seedlings cultivated in soil. The highest increase was observed in seedlings inoculated with K. radicincitans YD4 with an increase of 183 % in the dry shoot weight and a 30 % increase in shoot N content. In contrast, in compost, no increment in the dry weight was observed; however, an increase in content in some macronutrients in shoots was observed. Remarkably, when plant biomass was compared between soil and compost, seedlings inoculated with K. radicincitans YD4 in soil produced the highest yields, even though higher yields could be expected in compost due to the richness of this substrate. In conclusion, bio-inoculation of yerba mate seedlings with native PGPR increases the yield of this crop in nursery and could represent a promising sustainable strategy to improve yerba mate growth in low-fertility soils. - PublicationAccès libreEukaryotic plankton diversity in the sunlit ocean
; ; - PublicationAccès libreResponse of Sphagnum Testate Amoebae to Drainage, Subsequent Re-wetting and Associated Changes in the Moss Carpet: Results from a Three Year Mesocosm Experiment
; ; Sphagnum peatlands represent a globally significant pool and sink of carbon but these functions are threatened by ongoing climate change. Testate amoebae are useful bioindicators of hydrological changes, but little experimental work has been done on the impact of water table changes on communities.
Using a mesocosm experimental setting that was previously used to assess the impact of drought disturbance on communities and ecosystem processes with three contrasted water table positions: wet (–4 cm), intermediate (–15 cm) and dry (–25 cm), we studied the capacity of testate amoeba communities to recover when the water table was kept at –10 cm for all plots. The overall experiment lasted three years. We assessed the taxonomic and functional trait responses of testate amoeba communities. The selected traits were hypothesised to be correlated to moisture content (response traits: shell size, aperture position) or trophic role (effect traits: mixotrophy, aperture size controlling prey range).
During the disturbance phase, the mixotrophic species Hyalosphenia papilio dominated the wet and intermediate plots, while the community shifted to a dominance of “dry indicators” (Corythion dubium, Nebela tincta, Cryptodifflugia oviformis) and corresponding traits (loss of mixotrophy, and dominance of smaller taxa with ventral or ventral-central aperture) in dry plots. During the recovery phase we observed two contrasted trends in the previously wet and intermediate plots: communities remained similar where the Sphagnum carpet remained intact but species and traits indicators of drier conditions increased in plots where it had degraded. In the former dry plots, indicators and traits of wet conditions increased by the end of the experiment.
This is one of the first experiment simulating a disturbance and subsequent recovery in ex-situ mesocosms of Sphagnum peatland focusing on the response of testate amoebae community structure as well as functional traits to water table manipulation. The results generally confirmed that testate amoebae respond within a few months to hydrological changes and thus represent useful bioindicators for assessing current and past hydrological changes in Sphagnum peatlands. - PublicationAccès libreCreation of a raised bog in the Botanical garden of Neuchâtel: a tool for research, collections and public information
; ;
This object corresponds to the three missions of the garden : 1) to inform the public as well as students about these unusual, fragile and threatened ecosystems, 2) to present characteristic peatland plants from the Jura Mountains (Sphagnum, Drosera, Eriophorum, Betula nana, etc.), and 3) to conduct research projects.
During the winter 2014-15, the snow remained longer on the peatbog that on the adjacent path and meadow, thus providing evidence for a microclimatic effect of the bog. The excessively dry and hot summer 2015 allowed testing the resistance of the newly established bog vegetation. Most plants resisted well, including graminoids Eriophorum vaginatum, Trichophorum cespitosum or Carex sp., ericaceous (Vaccinium oxycoccos, myrtillus and vitis-idea) and mosses (especially Sphagnum). This living laboratory provides a unique opportunity to inform the public about the characteristics and functions of these ecosystems and the challenges of conserving and restoring them in a warmer world. - PublicationAccès libreA worldwide survey of neonicotinoids in honey
; ; ; Growing evidence for global pollinator decline is causing concern for biodiversity conservation and ecosystem services maintenance. Neonicotinoid pesticides have been identified or suspected as a key factor responsible for this decline. We assessed the global exposure of pollinators to neonicotinoids by analyzing 198 honey samples from across the world. We found at least one of five tested compounds (acetamiprid, clothianidin, imidacloprid, thiacloprid, and thiamethoxam) in 75% of all samples, 45% of samples contained two or more of these compounds, and 10% contained four or five. Our results confirm the exposure of bees to neonicotinoids in their food throughout the world. The coexistence of neonicotinoids and other pesticides may increase harm to pollinators. However, the concentrations detected are below the maximum residue level authorized for human consumption (average ± standard error for positive samples: 1.8 ± 0.56 nanograms per gram). - PublicationAccès libreSoil protistology rebooted: 30 fundamental questions to start with
; ; ; ; ; ; ; - PublicationAccès libreEnvironmental DNA COI barcoding for quantitative analysis of protists communities: A test using the Nebela collaris complex (Amoebozoa;Arcellinida; Hyalospheniidae)Environmental DNA surveys are used for screening eukaryotic diversity. However, it is unclear how quantitative this approach is and to what extent results from environmental DNA studies can be used for ecological studies requiring quantitative data. Mitochondrial cytochrome oxidase (COI) is used for species-level taxonomic studies of testate amoebae and should allow assessing the community composition from environmental samples, thus bypassing biases due to morphological identification. We tested this using a COI clone library approach and focusing on the Nebela collaris complex. Comparisons with direct microscopy counts showed that the COI clone library diversity data matched the morphologically identified taxa, and that community com-position estimates using the two approaches were similar. However, this correlation was improved when microscopy counts were corrected for biovolume. Higher correlation with biovolume-corrected community data suggests that COI clone library data matches the ratio of mitochondria and that within closely-related taxa the density of mitochondria per unit biovolume is approximately constant. Further developments of this metabarcoding approach including quantifying the mitochondrial density among closely-related taxa, experiments on other taxonomic groups and using high throughput sequencing should make if possible to quantitatively estimate community composition of different groups, which would be invaluable for microbial food webs studies.