Project description:Purpose: The recent publication of the fungal mutualist R. irregularis genome facilitated transcriptomic studies. We here adress the gene regulation of R. irregularis in response to root exudates from rice wild-type and osnope1 (no perception candidate - mutant unable to host arbuscular mycorrhizal fungi) Methods: Spores of R. irregularis were treated with root exudates and collected at 1 hour, 24 hours and 7 days after addition. To monitor fungal gene regulation, control conditions were also prepared at T0, 1h, 24h and 7d. mRNA were sequenced by HiSeq Illumina. Reads were mapped on the Rhizophagus irregularis genome assembly (Gloin1 - Tisserant et al., PNAS, 2013) using CLCworkbench suite. Results: -At 1h, a set of 92 fungal genes were found up-regulated in response to wt root exudates (92), not to osnope1 root exudates, many of them being involved in cell signaling. -At 24h and 7d, numerous genes putatively involved in primary metabolism were up-regulated in response to wt root exudates, not in response to osnope1 root exudates -Several vital genes involved in cell development are repressed in response to osnope1 RE compared to wt RE. Conclusions: these results argue for a high metabolic activity induced by wt root exudates, not by osnope1 root exudates.
Project description:Root exudates play an important role in plant-microbe interaction. The transcriptional profilings of plant growth-promoting rhizobacteria Bacillus amyloliquefaciens SQR9 in response to maize root exudates under static condition, were investigated by an Illumina RNA-seq for understanding the regulatory roles of the root exudates. 4 treatments, including 2 blank control (24 h and 48 h-post inoculation, named as 5 and 15, respectively), and 2 treatments with maize root exudates (24 h and 48 h-post inoculation, named as 7 and 17, respectively)
Project description:The presence of genetic groups of the entomopathogenic fungus Metarhizium anisopliae in soil is shaped by its adaptability to specific soil and habitat types, and by soil insect populations. Although the entomopathogenic life style of this fungus is well studied, its saprophytic life style has received little consideration. While a set of functionally related genes can be commonly expressed for the adaptability of this fungus to different environments (insect cuticle, insect blood and root exudates), a different subset of genes is also expected for each environment. In order to increase the knowledge of the potential use of M. anisopliae as a rhizosphere competent organism, in this study we evaluated the genetic expression of this fungus while growing on plant root exudates in laboratory conditions during a time course. One fungal strain: Metarhizium anisopliae ARSEF 2575; Five time conditions: 0h, 1h, 4h, 8h, 12h; Five-condition experiment: Time0h vs. Time1h, Time1h vs. Time4h, Time4h vs. Time8h, Time8h vs. Time12h and Time12h vs. Time0h. Two Biological replicates: independently grown and harvested. Three replicates per array. Dye-swap was performed on replicate 2.
Project description:Rhizosphere is a complex system of interactions between plant roots, bacteria, fungi and animals, where the release of plant root exudates stimulates bacterial density and diversity. However, the majority of the bacteria in soil results to be unculturable but active. The aim of the present work was to characterize the microbial community associated to the root of V. vinifera cv. Pinot Noir not only under a taxonomic perspective, but also under a functional point of view, using a metaproteome approach. Our results underlined the difference between the metagenomic and metaproteomic approach and the large potentiality of proteomics in describing the environmental bacterial community and its activity. In fact, by this approach, that allows to investigate the mechanisms occurring in the rhizosphere, we showed that bacteria belonging to Streptomyces, Bacillus and Pseudomonas genera are the most active in protein expression. In the rhizosphere, the identified genera were involved mainly in phosphorus and nitrogen soil metabolism.
Project description:The presence of genetic groups of the entomopathogenic fungus Metarhizium anisopliae in soil is shaped by its adaptability to specific soil and habitat types, and by soil insect populations. Although the entomopathogenic life style of this fungus is well studied, its saprophytic life style has received little consideration. While a set of functionally related genes can be commonly expressed for the adaptability of this fungus to different environments (insect cuticle, insect blood and root exudates), a different subset of genes is also expected for each environment. In order to increase the knowledge of the potential use of M. anisopliae as a rhizosphere competent organism, in this study we evaluated the genetic expression of this fungus while growing on plant root exudates in laboratory conditions during a time course.
2010-12-29 | GSE16848 | GEO
Project description:Fungal community diversity under different tillage treatments
Project description:Root exudates play an important role in plant-microbe interaction. The transcriptional profilings of plant growth-promoting rhizobacteria Bacillus amyloliquefaciens SQR9 in response to maize root exudates under static condition, were investigated by an Illumina RNA-seq for understanding the regulatory roles of the root exudates.
Project description:Plants and rhizosphere microbes rely closely on each other, with plants supplying carbon to bacteria in root exudates, and bacteria mobilizing soil-bound phosphate for plant nutrition. When the phosphate supply becomes limiting for plant growth, the composition of root exudation changes, affecting rhizosphere microbial communities and microbially-mediated nutrient fluxes. To evaluate how plant phosphate deprivation affects rhizosphere bacteria, Lolium perenne seedlings were root-inoculated with Pseudomonas aeruginosa 7NR, and grown in axenic microcosms under different phosphate regimes (330 uM vs 3-6 uM phosphate). The effect of biological nutrient limitation was examined by DNA microarray studies of rhizobacterial gene expression.
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.