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:Microbial communities in the rhizosphere make significant contributions to crop health and nutrient cycling. However, their ability to perform important biogeochemical processes remains uncharacterized. Important functional genes, which characterize the rhizosphere microbial community, were identified to understand metabolic capabilities in the maize rhizosphere using GeoChip 3.0-based functional gene array method. Triplicate samples were taken for both rhizosphere and bulk soil, in which each individual sample was a pool of four plants or soil cores. To determine the abundance of functional genes in the rhizosphere and bulk soils, GeoChip 3.0 was used.
Project description:Microbial communities in the rhizosphere make significant contributions to crop health and nutrient cycling. However, their ability to perform important biogeochemical processes remains uncharacterized. Important functional genes, which characterize the rhizosphere microbial community, were identified to understand metabolic capabilities in the maize rhizosphere using GeoChip 3.0-based functional gene array method. Triplicate samples were taken for both rhizosphere and bulk soil, in which each individual sample was a pool of four plants or soil cores. To determine the abundance of functional genes in the rhizosphere and bulk soils, GeoChip 3.0 was used.
Project description:In this study, blueberry transcriptomics and rhizosphere fungal diversity were analyzed by simulated potting method to treat blueberries with Cd stress, and the content of Fe, Mn, Cu, Zn and Cd in each tissue, soil and DGT of blueberries were determined. , Combined with transcriptomics for correlation analysis. A total of 84374 annotated genes were obtained in blueberry roots, stems, leaves and fruits, of which 3370 DEGs were found, and DEGs in the stem accounted for the highest proportion, totaling 2521. The annotation results show that these DEGs are mainly concentrated in a series of metabolic pathways related to signal transduction, defense and pathogenic response. Blueberries transfer excess Cd from the root to the stem for storage. The stem contains the highest Cd content, which is consistent with the transcriptomics analysis results, while the fruit contains the lowest Cd content. Correlation analysis between heavy metal content and transcriptomics results in each tissue was carried out, and a series of genes related to Cd regulation were screened. The blueberry root system relies on mycorrhiza to absorb nutrients in the soil. The intervention of Cd has severely affected the microflora structure of the blueberry rhizosphere soil. Coniochaetaceae, which is extremely tolerant, has gradually become the dominant population.