Project description:A3_Microorganisms under Elevated CO2 along with elevated temperature (550 ppm along with 2 degree higher temperature compared to control chamber) Metagenome
Project description:The atmosphere CO2 concentration keeps increasing every year. Use the Affymetrix poplar gene chip to confirm the expression changes in key genes in the triploid white poplar due to the influence of elevated CO2 concentrations. We used microarrays to detail the global programme of gene expression under normal and elevated CO2 concentrations. Gene expression of triploid white poplar ((P. tomentosa Ã? P. bolleanaï¼?Ã? P. tomentosa) leaves were investigated by using the Affymetrix poplar genome gene chip, after grown in controlled environment chambers under three different CO2 concentrations. Poplar leaves were subjected to normal CO2 concentrations (T0) and elevated CO2 concentrations (T1, 550 ppm and T2, 720 ppm) treatments three months.
Project description:To study long-term elevated CO2 and enriched N deposition interactive effects on microbial community and soil ecoprocess, here we investigated soil microbial community in a grassland ecosystem subjected to ambient CO2 (aCO2, 368 ppm), elevated CO2 (eCO2, 560 ppm), ambient nitrogen deposition (aN) or elevated nitrogen deposition (eN) treatments for a decade. There exist antagonistic CO2×N interactions on microbial functional genes associated with C, N, P S cycling processes. More strong antagonistic CO2×N interactions are observed on C degradation genes than other genes. Remarkably antagonistic CO2×N interactions on soil microbial communities could enhance soil C accumulation.
Project description:This work aims to study the effect of the elevated CO2 concentration on the tomato plant response to the toxicity provoked by ammonium nutrition. Tomato plants (Solanum lycopersicum L. cv. Agora Hybrid F1, Vilmorin®) were grown for 4 week with 15 mM of nitrogen, supplied as nitrate or ammonium, at ambient or elevated CO2 conditions (400 ppm or 800 ppm). Transcription profiling by array was carried out in roots for the four growth conditions assayed and gene expression comparisons were done between N sources and CO2 conditions: i) genes differentially expressed in response to the atmospheric CO2 concentration (800 ppm vs 400 ppm CO2) under nitrate or ammonium nutrition; ii) genes differentially expressed in response to the N source (ammonium vs nitrate) under ambient or elevated condition. 3 biological replicates for each growth condition were analysed.CO2).
Project description:Transcriptional reprogramming and stimulation of leaf respiration by elevated CO2 concentration is diminished, but not eliminated, under limiting nitrogen supply. Arabidopsis plants were grown in either ambient (370 ppm) or elevated (750 ppm) CO2 with either ample N supply or limiting N supply. Leaf tissue was harvested from youngest most fully expanded leaves 35 days after plant germination at either midday or midnight.
Project description:Global CO2 level presently recorded at 400 ppm is expected to reach 550 ppm in 2050, an increment likely to impact plant growth and productivity. Using targeted LC-MS and GC-MS platforms we quantified 229 and 29 metabolites, respectively in a time-course study to reveal short-term responses to different concentrations (1, 3, and 10 mM) of bicarbonate (HCO3-) under light and dark conditions. Results indicate that HCO3- treatment responsive metabolomic changes depend on the HCO3- concentration, time of treatment, and light/dark. Interestingly, 3 mM HCO3- concentration treatment induced more significantly changed metabolites than either lower or higher concentrations used. Flavonoid biosynthesis and glutathione metabolism were common to both light and dark-mediated responses in addition to showing concentration-dependent changes. Our metabolomics results provide insights into short-term plant cellular responses to elevated HCO3- concentrations as a result of ambient increases in CO2 under light and dark.
Project description:Anthropogenic CO2 presently at 400 ppm is expected to reach 550 ppm in 2050, an increment expected to affect plant growth and productivity. Paired stomatal guard cells (GCs) are the gate-way for water, CO2, and pathogen, while mesophyll cells (MCs) represent the bulk cell-type of green leaves mainly for photosynthesis. We used the two different cell types, i.e., GCs and MCs from canola (Brassica napus) to profile metabolomic changes upon increased CO2 through supplementation with bicarbonate (HCO3-). Two metabolomics platforms enabled quantification of 268 metabolites in a time-course study to reveal short-term responses. The HCO3- responsive metabolomes of the cell types differed in their responsiveness. The MCs demonstrated increased amino acids, phenylpropanoids, redox metabolites, auxins and cytokinins, all of which were decreased in GCs in response to HCO3-. In addition, the GCs showed differential increases of primary C-metabolites, N-metabolites (e.g., purines and amino acids), and defense-responsive pathways (e.g., alkaloids, phenolics, and flavonoids) as compared to the MCs, indicating differential C/N homeostasis in the cell-types. The metabolomics results provide insights into plant responses and crop productivity under future climatic changes where elevated CO2 conditions are to take center-stage.
Project description:To study whether and how soil nitrogen conditions affect the ecological effects of long-term elevated CO2 on microbial community and soil ecoprocess, here we investigated soil microbial community in a grassland ecosystem subjected to ambient CO2 (aCO2, 368 ppm), elevated CO2 (eCO2, 560 ppm), ambient nitrogen deposition (aN) or elevated nitrogen deposition (eN) treatments for a decade. Under the aN condition, a majority of microbial function genes, as measured by GeoChip 4.0, were increased in relative abundance or remained unchanged by eCO2. Under the eN condition, most of functional genes associated with carbon, nitrogen and sulfur cycling, energy processes, organic remediation and stress responses were decreased or remained unchanged by eCO2, while genes associated with antibiotics and metal resistance were increased. The eCO2 effects on fungi and archaea were largely similar under both nitrogen conditions, but differed substantially for bacteria. Coupling of microbial carbon or nitrogen cycling genes, represented by positive percentage and density of gene interaction in association networks, was higher under the aN condition. In accordance, changes of soil CO2 flux, net N mineralization, ammonification and nitrification was higher under the aN condition. Collectively, these results demonstrated that eCO2 effects are contingent on nitrogen conditions, underscoring the difficulty toward predictive modeling of soil ecosystem and ecoprocesses under future climate scenarios and necessitating more detailed studies.