Project description:Purpose: The goal of this study is to evaluate transcriptional regulation of the accumulation of phenols and anthocyanins in young leaves of subtropical forest tree species by using NGS-derived RNA-seq. Methods: Leaf mRNA profiles of subtropical tree Schima superba and Cryptocarya concinna grown under contasting light were generated by deep sequencing, in triplicate, using Illumina. The sequence reads that passed quality filters were analyzed at the transcript isoform level with TopHat followed by Cufflinks. FPKM produced by RSEM are provided. Results: Assemblies of the sequence data yielded 61,618 and 64,413 unigenes for Schima superba and Cryptocarya concinna,respectively. Overall,75.14% and 66.46% of the unigenes were annotated in the protein database Nonredundant protein (Nr), Nonredundant nucleotide (Nt), Swiss-Prot、Kyoto Encyclopedia of Genes and Genomes (KEGG), Cluster of Orthologous Groups of proteins (COG) and Gene Ontology (GO) for S. superba and C concinna,respectively.A total of 3896, 3488 and 266 genes were differentially expressed in full light-exposed young leaf (FLY), low light-exposed young leaf (LYL) and low light-exposed mature leaf (LML) relative to low light-exposed mature leaf (FML) of S. superba, respectively, and 2097, 2047 and 211 genes were differentially expressed in the corresponding leaves of C. concinna. Conclusions: Our study represents the first detailed analysis of transcriptomes in young and mature leaves of dorminant trees from a subtropical forest in China, with biologic replicates, generated by RNA-seq technology. Photosynthesis-related genes and phenol pathways-related genes were extensively down- and up-regulated in young versus mature leaves of the two species.
Project description:Simulated drought changes arbuscular mycorrhizal fungal biomass and root colonization rather than community in different growth seasons in a subtropical forest
Project description:Soil fungal communities, which drive many ecosystem processes, vary across soil horizons. However, how fungal communities are influenced by soil horizon layers remains largely unstudied. In this study, soil samples were collected from the organic horizon (O horizon) and mineral matter horizon (M horizon) in two sites of Dabie Mountain, China, and the effects of the two horizons on the soil fungal community composition were assessed based on Illumina MiSeq sequencing. Our results showed that soil fungal community composition varied with soil horizons, and soil fungal species richness and diversity in the O horizon were significantly higher than that in the M horizon. Total organic carbon (TOC), total organic nitrogen (TON), alkali-hydrolyzable nitrogen (AHN), available potassium (AK), and available phosphorus (AP) significantly influenced fungal community composition, abundance, and diversity across the two horizons (P < 0.05). Furthermore, precipitation was found to have a significant effect on fungal community composition. Our results demonstrate changes in fungal communities across soil horizons and highlight the importance of soil organic matter on fungal communities and diversity.
Project description:<p>Plants produce thousands of compounds, collectively called the metabolome, which mediate interactions with other organisms. The metabolome of an individual plant may change according to the number and nature of these interactions. We tested the hypothesis that tree diversity level affects the metabolome of four subtropical tree species in a biodiversity ecosystem-functioning experiment, BEF-China. We postulated that the chemical diversity of leaves, roots and root exudates increases with tree diversity. We expected the strength of this diversity effect to differ among leaf, root and root exudates samples. Considering their role in plant competition, we expected to find the strongest effects in root exudates. In an ecometabolomics approach, roots, root exudates and leaves of four tree species (Cinnamomum camphora, Cyclobalanopsis glauca, Daphniphyllum oldhamii, Schima superba) were sampled from selected plots in BEF-China. Samples were extracted and analysed using Liquid Chromatography-Time of Flight-Mass Spectrometry. The exudate metabolomes were normalized over their non-purgeable organic carbon level. Multivariate analyses were applied to identify the effect of both neighbouring (local) trees and plot diversity on tree metabolomes. The species and sample specific metabolites were assigned to major compound classes using the ClassyFire tool, whereas m/z features related to diversity effects were annotated manually. Individual tree species showed distinct leaf, root and root exudate metabolomes. The main compound class in leaves were the flavonoids, whereas carboxylic acids, prenol lipids and specific alkaloids were most prominent in root exudates and roots. Overall plot diversity had a stronger effect on metabolome profiles than the diversity of local, directly neighbouring trees. Leaf metabolomes responded more often to tree diversity level than exudates, whereas root metabolomes varied the least. We found not overall correlation between metabolite richness or diversity and tree diversity. Synthesis: Classification of metabolites supported initial ecological interpretation of differences among species and organs. Particularly the metabolomes of leaves and root exudates respond to differences in tree diversity. These responses were neither linear nor uniform and individual metabolites showed different dynamics. More controlled interaction experiments are needed to dissect the causes and consequences of the observed shifts in plant metabolomes.</p>