Project description:Background: The soil environment is responsible for sustaining most terrestrial plant life on earth, yet we know surprisingly little about the important functions carried out by diverse microbial communities in soil. Soil microbes that inhabit the channels of decaying root systems, the detritusphere, are likely to be essential for plant growth and health, as these channels are the preferred locations of new root growth. Understanding the microbial metagenome of the detritusphere and how it responds to agricultural management such as crop rotations and soil tillage will be vital for improving global food production. Methods: The rhizosphere soils of wheat and chickpea growing under + and - decaying root were collected for metagenomics sequencing. A gene catalogue was established by de novo assembling metagenomic sequencing. Genes abundance was compared between bulk soil and rhizosphere soils under different treatments. Conclusions: The study describes the diversity and functional capacity of a high-quality soil microbial metagenome. The results demonstrate the contribution of the microbiome from decaying root in determining the metagenome of developing root systems, which is fundamental to plant growth, since roots preferentially inhabit previous root channels. Modifications in root microbial function through soil management, can ultimately govern plant health, productivity and food security.
Project description:The cotyledons of etiolated seedlings from terrestrial flowering plants must emerge from the soil surface, while roots must penetrate the soil to ensure plant survival. We show here that the soil emergence related transcription factor PHYTOCHROME-INTERACTING FACTOR 3 (PIF3) regulates root penetration via transducing external signals perceived by the receptor kinase FERONIA (FER) in Arabidopsis thaliana. The loss of FER function in the fer-4 mutant resulted in a severe defect in root penetration into hard soil or medium. Single-cell RNA-seq profiling of roots revealed a distinct cell clustering pattern, especially for root cap cells, and revealed PIF3 as a putative FER-regulated transcription factor. Biochemical, imaging, and genetic experiments confirmed that PIF3 is required for root soil penetration. Moreover, FER interacted with and stabilized PIF3, which then modulated the expression of mechanosensitive ion channels and the sloughing of outer cells in the root cap. We propose a novel mechanism of soil penetration by plant roots.
2023-12-31 | GSE225299 | GEO
Project description:Soil and root metabarcoding on Lord Howe Island
Project description:Transcriptome analysis of root development related genes in terrestrial and hydroponic ramie. Ramie seedlings were cultivated in soil, and in hydroponic with the shoot-cutting propagation method. The root samples from hydrophonic ramie were collected from the early stage (5-day-old seedling) and the late stage (30-day-old seedling) of acquatic roots induction. The roots of ramie seedling cultivated in soil were also collected for comparative analysis. Our study represents the detailed analysis of ramie root transcriptomes with biologic replicates.
Project description:We investigated the toxicity of soil samples derived from a former municipal landfill site in the South of the Netherlands, where a bioremediation project is running aiming at reusing the site for recreation. Both an organic soil extract and the original soil sample was investigated using the ISO standardised Folsomia soil ecotoxicological testing and gene expression analysis. The 28 day survival/reproduction test revealed that the ecologically more relevant original soil sample was more toxic than the organic soil extract. Microarray analysis showed that the more toxic soil samples induced gene regulatory changes in twice as less genes compared to the soil extract. Consequently gene regulatory changes were highly dependent on sample type, and were to a lesser extent caused by exposure level. An important biological process shared among the two sample types was the detoxification pathway for xenobiotics (biotransformation I, II and III) suggesting a link between compound type and observed adverse effects. Finally, we were able to retrieve a selected group of genes that show highly significant dose-dependent gene expression and thus were tightly linked with adverse effects on reproduction. Expression of four cytochrome P450 genes showed highest correlation values with reproduction, and maybe promising genetic markers for soil quality. However, a more elaborate set of environmental soil samples is needed to validate the correlation between gene expression induction and adverse phenotypic effects.
Project description:Arsenic (As) bioavailability in the rice rhizosphere is influenced by many microbial interactions, particularly by metal-transforming functional groups at the root-soil interface. This study was conducted to examine As-transforming microbes and As-speciation in the rice rhizosphere compartments, in response to two different water management practices (continuous and intermittently flooded), established on fields with high to low soil-As concentration. Microbial functional gene composition in the rhizosphere and root-plaque compartments were characterized using the GeoChip 4.0 microarray. Arsenic speciation and concentrations were analyzed in the rhizosphere soil, root-plaque, porewater and grain samples. Results indicated that intermittent flooding significantly altered As-speciation in the rhizosphere, and reduced methyl-As and AsIII concentrations in the pore water, root-plaque and rice grain. Ordination and taxonomic analysis of detected gene-probes indicated that root-plaque and rhizosphere assembled significantly different metal-transforming functional groups. Taxonomic non-redundancy was evident, suggesting that As-reduction, -oxidation and -methylation processes were performed by different microbial groups. As-transformation was coupled to different biogeochemical cycling processes establishing functional non-redundancy of rice-rhizosphere microbiome in response to both rhizosphere compartmentalization and experimental treatments. This study confirmed diverse As-biotransformation at root-soil interface and provided novel insights on their responses to water management, which can be applied for mitigating As-bioavailability and accumulation in rice grains.
Project description:Root and leave samples of 4 different apple genotypes were investigated in order to analyse the gene expression after infection with Apple Replant Disease (ARD). All genotypes were cultivated in ARD-infected soil and gamma-irradiated (disinfected) soil in the greenhouse for 7 days. The ARD soil originated from two different orchards representing two different soil compositions. After 7 days root tissue was collected from each plant and used for the subsequent gene expression analysis. This work was part of the project BonaRes-ORDIAmur funded by the German Federal Ministry of Research and Education within the frame of the program BonaRes (grant no. 031B0025B). It was also funded by the German Research Foundation (DFG) via the research training group GRK1798 "Signaling at the Plant-Soil Interface" and a grant to BL and LB (BE 1174/19-1).
Project description:We addressed the question how the interaction between the beneficial root endophyte Serendipita vermifera (Sv) and the pathogen Bipolaris sorokiniana (Bs) affects fungal behavior and determines barley host responses using a gnotobiotic natural soil-based split-root system for phenotypic and transcriptional analyses.
Project description:Elevated growth temperatures are negatively affecting crop productivity and increasing yield losses. Root traits associated with improved adaptation to rising temperatures are a promising approach to generate new varieties better suited to face the environmental constrains caused by climate change. In this study, we identified various Brassica napus roots traits altered in response to warm temperature. Thus, different combination of changes in specific root traits results in an extended and deeper root system. This overall root growth expansion facilitates root adaptation by maximizing root-soil surface interaction and increasing its ability to explore extended soil areas. We associated these traits to coordinated cellular events, including changes in cell division and elongation rates, that drive the increase in root growth triggered by warm temperature. Comparative genome wide transcriptomic analysis revealed the main genetic determinants of these RSA changes and uncovered the necessity of a tight regulation of the heat shock stress response to adjust root growth to warm temperature. Our work provides a phenotypic, cellular and genetic framework of root response to warming temperatures that will help to harness root adaptation mechanisms for crop yield improvement under the future climatic scenario.