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:Metagenome data from soil samples were collected at 0 to 10cm deep from 2 avocado orchards in Channybearup, Western Australia, in 2024. Amplicon sequence variant (ASV) tables were constructed based on the DADA2 pipeline with default parameters.
Project description:The contamination of agricultural soil by heavy metal cadmium (Cd) poses a significant environmental challenge, affecting crop growth, development and, human health. Previous studies have established the pivotal role of the ZmHMA3 gene, a P-type ATPase heavy metal transporter, in determining variable Cd accumulation in maize grains among 513 inbred lines. To decipher the molecular mechanism underlying mutation-induced phenotypic differences mediated by ZmHMA3, we conducted a quantitative Tandem Mass Tag (TMT)-based proteomic analysis of immature maize kernels. This analysis aimed to identify differentially expressed proteins (DEPs) in wild-type B73 and zmhma3 null mutant under Cd stress. The findings demonstrated that zhma3 accumulated higher levels of Cd compared to B73 when exposed to varying Cd concentrations in the soil. In comparison to low Cd concentration soil, B73 and zmhma3 exhibited 75 and 142 DEPs, respectively, with 24 common DEPs shared between them. Zmhma3 showed a higher induction of upregulated genes related to Cd stres than B73. Amino sugar and nucleotide sugar metabolism were specifically enriched in B73, while phenylpropanoid biosynthesis, nitrogen metabolism, and glyoxylate and dicarboxylate metabolism appeared to play a more significant role in zmhma3. This study provides proteomics insights into unraveling the molecular mechanism underlying the differences in Cd accumulation in maize kernel.
Project description:The main objective of this work was to evaluate the toxicity of Cd, in different genotypes of T. cacao, in scion-rootstock combinations (CCN 51-BN 34, CCN 51-PS 1319, CCN 51-PH 16, CCN 51-CCN 51), grown in soil with 150 mg Cd kg-1 soil, together with the control treatment (without addition of Cd in the soil), through proteomic profile, aiming to elucidate the influence of the scion-rootstock interaction on differential uptake and accumulation of Cd in roots and leaves.
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.
Project description:The fate of the carbon stocked in permafrost soils following global warming and permafrost thaw is of major concern in view of the potential for increased CH4 and CO2 emissions from these soils. Complex carbon compound degradation and greenhouse gas emissions are due to soil microbial communities, but their composition and functional potential in permafrost soils are largely unknown. Here, a 2 m deep permafrost and its overlying active layer soil were subjected to metagenome sequencing, quantitative PCR, and microarray analyses. The active layer soil and 2 m permafrost soil microbial community structures were very similar, with Actinobacteria being the dominant phylum. The two soils also possessed a highly similar spectrum of functional genes, especially when compared to other already published metagenomes. Key genes related to methane generation, methane oxidation and organic matter degradation were highly diverse for both soils in the metagenomic libraries and some (e.g. pmoA) showed relatively high abundance in qPCR assays. Genes related to nitrogen fixation and ammonia oxidation, which could have important roles following climatic change in these nitrogen-limited environments, showed low diversity but high abundance. The 2 m permafrost soil showed lower abundance and diversity for all the assessed genes and taxa. Experimental biases were also evaluated and showed that the whole community genome amplification technique used caused large representational biases in the metagenomic libraries. This study described for the first time the detailed functional potential of permafrost-affected soils and detected several genes and microorganisms that could have crucial importance following permafrost thaw. A 2m deep permafrost sample and it overlying active layer were sampled and their metagenome analysed. For microarray analyses, 8 other soil samples from the same region were used for comparison purposes.
Project description:For environmental safety, the high concentration of heavy metals in the soil should be removed. Cadmium (Cd), one of the heavy metals polluting the soil while its concentration exceeds 3.4 mg/kg in soil. Potential use of cotton for remediating heavy Cd-polluted soils is available while its molecular mechanisms of Cd tolerance remains unclear in cotton. In this study, transcriptome analysis was used to identify the Cd tolerance genes and their potential mechanism in cotton. Finally 4,627 differentially expressed genes (DEGs) in the root, 3,022 DEGs in the stem and 3,854 DEGs in leaves were identified through RNA-Seq analysis, respectively. These genes contained heavy metal transporter genes (ABC, CDF, HMA, etc.), annexin genes, heat shock genes (HSP) amongst others. Gene ontology (GO) analysis showed that the DEGs were mainly involved in the oxidation-reduction process and metal ion binding. The DEGs mainly enriched in two pathways, the influenza A and the pyruvate pathway. GhHMAD5 protein, containing a heavy-metal domain, was identified in the pathway to transport or to detoxify the heavy ion. GhHMAD5-overexpressed plants of Arabidopsis thaliana showed the longer roots compared with the control. Meanwhile, GhHMAD5-silenced cotton plants showed more sensitive to Cd stress compared with the control. The results indicated that GhHMAD5 gene is remarkably involved in Cd tolerance, which gives us a preliminary understanding of Cd tolerance mechanisms in upland cotton. Overall, this study provides valuable information for the use of cotton to remediate the soil polluted with heavy metals.