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World Journal of Microbiology &... Oct 2023The continuous cropping obstacle is the main factor in leading to difficulty in American ginseng replanting. The dormant microbiota in the soil may be the cause of...
The continuous cropping obstacle is the main factor in leading to difficulty in American ginseng replanting. The dormant microbiota in the soil may be the cause of American ginseng disease and eventually caused continuous cropping obstacles, but there are few studies on the dynamic changes of soil microenvironment after American ginseng planting. In this study, we tracked short-term variation in physicochemical properties, enzyme activities, and fungal communities over time-series in soils with continuous cropping obstacle under crop rotation and probiotic Bacillus treatments. Furthermore, we examined the relationships between the important fungal compositions and the soil properties. The results showed that sucrase, cellulase, urease and acid phosphatase activities were significantly increased, while catalase and dehydrogenase were decreased with treatments time. Rotation treatment significantly affected the diversity, dissimilarity degree and species distribution of soil fungal community with continuous cropping obstacle over a short-term. Moreover, beneficial fungal biomarkers such as Cladorrhinum, Oidiodendron, and Mariannaea were accumulated at 48 h under rotation treatments. Almost all fungal biomarkers were negatively correlated with hydrolases and positively correlated with oxidoreductases and acid phosphatase under crop rotation treatments. This study suggested that compared to probiotic Bacillus, crop rotation can significantly affect soil fungal community structure, especially the enrichment of specific potentially beneficial fungal species. Our findings provide a scientific basis for understanding the dynamic changes of fungal communities and soil properties with continuous cropping obstacle of American ginseng in initial stage of soil improvement.
Topics: Soil; Mycobiome; Bacillus; Panax; Acid Phosphatase; Biomarkers; Soil Microbiology
PubMed: 37874395
DOI: 10.1007/s11274-023-03807-w -
Molecular Plant-microbe Interactions :... Nov 2009The genome sequences of mycorrhizal fungi will provide new opportunities for studying the biology and the evolution underlying this symbiotic lifestyle. The generation...
The genome sequences of mycorrhizal fungi will provide new opportunities for studying the biology and the evolution underlying this symbiotic lifestyle. The generation of null mutants at the wild-type loci is one of the best methods for gene-function assignment in the post-genomic era. To our knowledge, the generation of superoxide dismutase 1 (SOD1)-null mutants in the ericoid mycorrhizal fungus Oidiodendron maius is the first example of a gene-targeted disruption via homologous recombination in a mycorrhizal fungus. The disruption of OmSOD1 by Agrobacterium-mediated transformation resulted in the presence of oxidative stress markers, even in the absence of external superimposed stresses, and an increased sensitivity to reactive oxygen species (ROS)-generating substances, especially to menadione. A reduction in conidiation and in the percentage of mycorrhization of Vaccinium myrtillus roots was also observed. The latter findings establish the pivotal role of SOD1 as an important factor in the relationship between O. maius and its symbiotic partner. The lack of this ROS-scavenger may cause an imbalance in the redox homeostasis during host colonization and an alteration in the delicate dialogue between the fungus and its host plant.
Topics: Gene Expression Regulation, Enzymologic; Gene Expression Regulation, Fungal; Mutation; Mycorrhizae; Oxidative Stress; Plant Root Nodulation; Plant Roots; Spores, Fungal; Superoxide Dismutase; Superoxide Dismutase-1; Vaccinium myrtillus
PubMed: 19810810
DOI: 10.1094/MPMI-22-11-1412 -
Journal of Microbiology and... May 2021is an ectomycorrhizal fungus that has a symbiotic relationship with the root of . Soil microbial communities greatly affect the growth of , however, few studies have...
is an ectomycorrhizal fungus that has a symbiotic relationship with the root of . Soil microbial communities greatly affect the growth of , however, few studies have examined the characteristics of these communities. In the present study, we analyzed soil fungal communities from Gyeongju and Yeongdeok using metagenomic pyrosequencing to investigate differences in fungal species diversity, richness, and taxonomic composition between the soil under fruiting bodies (Sample 2) and soil where the fairy ring of was no longer present (Sample 1). The same spot was investigated three times at intervals of four months to observe changes in the community. In the samples from Yeongdeok, the number of valid reads was lower than that at Gyeongju. The operational taxonomic units of most Sample 2 groups were less than those of Sample 1 groups, indicating that fungal diversity was low in the dominant soil. The soil under the fruiting bodies was dominated by more than 51% . From fall to the following spring, the ratio of decreased. Basidiomycota was the dominant phylum in most samples. G-F1-2, G-F2-2, and Y-F1-2 had the genera , and in common. G-F1-1, G-F2-1, and Y-F1-1 had 10 genera including and in common. From fall to the following spring, the amount of phyla Basidiomycota and Mucoromycota gradually decreased but that of phylum Ascomycota increased. We suggest that the genus is positively related to .
Topics: Agaricales; Fungi; High-Throughput Nucleotide Sequencing; Metagenomics; Mycobiome; Pinus; Republic of Korea; Seasons; Soil Microbiology
PubMed: 33782219
DOI: 10.4014/jmb.2103.03021 -
The New Phytologist Feb 2018Some soil fungi in the Leotiomycetes form ericoid mycorrhizal (ERM) symbioses with Ericaceae. In the harsh habitats in which they occur, ERM plant survival relies on... (Comparative Study)
Comparative Study
Some soil fungi in the Leotiomycetes form ericoid mycorrhizal (ERM) symbioses with Ericaceae. In the harsh habitats in which they occur, ERM plant survival relies on nutrient mobilization from soil organic matter (SOM) by their fungal partners. The characterization of the fungal genetic machinery underpinning both the symbiotic lifestyle and SOM degradation is needed to understand ERM symbiosis functioning and evolution, and its impact on soil carbon (C) turnover. We sequenced the genomes of the ERM fungi Meliniomyces bicolor, M. variabilis, Oidiodendron maius and Rhizoscyphus ericae, and compared their gene repertoires with those of fungi with different lifestyles (ecto- and orchid mycorrhiza, endophytes, saprotrophs, pathogens). We also identified fungal transcripts induced in symbiosis. The ERM fungal gene contents for polysaccharide-degrading enzymes, lipases, proteases and enzymes involved in secondary metabolism are closer to those of saprotrophs and pathogens than to those of ectomycorrhizal symbionts. The fungal genes most highly upregulated in symbiosis are those coding for fungal and plant cell wall-degrading enzymes (CWDEs), lipases, proteases, transporters and mycorrhiza-induced small secreted proteins (MiSSPs). The ERM fungal gene repertoire reveals a capacity for a dual saprotrophic and biotrophic lifestyle. This may reflect an incomplete transition from saprotrophy to the mycorrhizal habit, or a versatile life strategy similar to fungal endophytes.
Topics: Conserved Sequence; Fungi; Gene Expression Regulation, Fungal; Genes, Fungal; Genomics; Mycorrhizae; Phylogeny; Plants; Secondary Metabolism; Substrate Specificity; Symbiosis; Transcriptome; Up-Regulation
PubMed: 29315638
DOI: 10.1111/nph.14974 -
The New Phytologist Mar 2001• Nuclear ribosomal sequence analysis was performed to investigate delimitation of common Oidiodendron species comprising endomycorrhizal symbionts and close...
• Nuclear ribosomal sequence analysis was performed to investigate delimitation of common Oidiodendron species comprising endomycorrhizal symbionts and close associates of ectomycorrhizal plants. • Neighbour-joining, maximum likelihood and parsimony analyses were used to compare 35 ribosomal DNA (internal transcribed spacer (ITS) and 5.8S) sequences (including sequences available in databases) from 15 putative species. • Oidiodendron citrinum formed a monophyletic group nested within O. maius, whereas O. tenuissimum and O. griseum did not appear either as distinct groups or as a single complex. Pairwise nucleotide divergence values between O. citrinum and O. maius were very low and comparable to intraspecific values obtained for both species; values for O. griseum and O. tenuissimum, although higher, overlapped those observed at the intraspecific level for the two species. • Molecular data indicate that O. maius and O. citrinum, which were described as distinct, though related species, could be moved to a subspecific level; however, the delimitation of O. griseum and O. tenuissimum is still open to question. Taxonomic rank assignment to groups determined from sequence data analysis is discussed.
PubMed: 33873341
DOI: 10.1046/j.1469-8137.2001.00058.x -
Frontiers in Plant Science 2022The application of Ericoid mycorrhizal (ErM) fungi is considered to be an important strategy for increasing plant yield and drought resistance. In this study, we...
The application of Ericoid mycorrhizal (ErM) fungi is considered to be an important strategy for increasing plant yield and drought resistance. In this study, we isolated and identified two ErM fungi that can promote the growth of lingonberry. We tried to understand the potential of these two ErM fungi to promote the growth of lingonberry and the strategies to help plants cope with water shortage. The use value of ErM fungi was evaluated by inoculating FC (FC) or ZL6 (ZL6), well-watered (WW) and severe drought stress (SDS). The results showed that the mycelium of ZL6 was denser than that of FC, and both ErM fungi significantly increased the biomass of lingonberry stems and roots. They also significantly increased the chlorophyll content by 65.6 and 97.8%, respectively. In addition, inoculation with ZL6 fungi can improve drought resistance, promote root growth and increase root wet weight by 1157.6%. Drought reduced the chlorophyll content and soluble sugar content of lingonberry but increased significantly after inoculation with ZL6. Inoculation with ZL6 decreased lingonberry's malondialdehyde (MDA) content but increased the superoxide dismutase (SOD) activity. Overall, these results indicated that the successful coexistence of ErM fungi and lingonberry alleviated the adverse effects of drought stress through higher secondary metabolites and photosynthetic pigment synthesis.
PubMed: 35755649
DOI: 10.3389/fpls.2022.920338 -
Fungal Genetics and Biology : FG & B Mar 2013Two full-length cDNAs (OmZnT1 and OmFET) encoding membrane transporters were identified by yeast functional screening in the heavy metal tolerant ericoid mycorrhizal...
Two full-length cDNAs (OmZnT1 and OmFET) encoding membrane transporters were identified by yeast functional screening in the heavy metal tolerant ericoid mycorrhizal isolate Oidiodendron maius Zn. OmZnT1 belongs to the Zn-Type subfamily of the cation diffusion facilitators, whereas OmFET belongs to the family of iron permeases. Their properties were investigated in yeast by functional complementation of mutants affected in metal uptake and metal tolerance. Heterologous expression of OmZnT1 and OmFET in a Zn-sensitive yeast mutant restored the wild-type phenotype. Additionally, OmZnT1 expression also restored cobalt tolerance in a Co-sensitive mutant. A GFP fusion protein revealed that OmZnT1 was targeted to the endoplasmic reticulum membrane, a result consistent with a function for OmZnT1 in metal sequestration. Similarly to other iron permeases, OmFET-GFP was localized on the plasma membrane. OmFET restored the growth of uptake-defective strains for iron and zinc. Zinc-sensitive yeast mutants expressing OmFET specifically accumulated magnesium, as compared to cells transformed with the empty vector. We suggest that OmFET may counteract zinc toxicity by increasing entry of magnesium into the cell.
Topics: Ascomycota; Endoplasmic Reticulum; Gene Expression Regulation, Fungal; Green Fluorescent Proteins; Heavy Metal Poisoning; Iron; Membrane Transport Proteins; Poisoning; Zinc
PubMed: 23232015
DOI: 10.1016/j.fgb.2012.11.004 -
The Science of the Total Environment Mar 2024Anthropogenic nitrogen (N) deposition and fertilization in boreal forests frequently reduces decomposition and soil respiration and enhances C storage in the topsoil....
Anthropogenic nitrogen (N) deposition and fertilization in boreal forests frequently reduces decomposition and soil respiration and enhances C storage in the topsoil. This enhancement of the C sink can be as strong as the aboveground biomass response to N additions and has implications for the global C cycle, but the mechanisms remain elusive. We hypothesized that this effect would be associated with a shift in the microbial community and its activity, and particularly by fungal taxa reported to be capable of lignin degradation and organic N acquisition. We sampled the organic layer below the intact litter of a Norway spruce (Picea abies (L.) Karst) forest in northern Sweden after 20 years of annual N additions at low (12.5 kg N ha yr) and high (50 kg N ha yr) rates. We measured microbial biomass using phospholipid fatty-acid analysis (PLFA) and ergosterol measurements and used ITS metagenomics to profile the fungal community of soil and fine-roots. We probed the metabolic activity of the soil community by measuring the activity of extracellular enzymes and evaluated its relationships with the most N responsive soil fungal species. Nitrogen addition decreased the abundance of fungal PLFA markers and changed the fungal community in humus and fine-roots. Specifically, the humus community changed in part due to a shift from Oidiodendron pilicola, Cenococcum geophilum, and Cortinarius caperatus to Tylospora fibrillosa and Russula griseascens. These microbial community changes were associated with decreased activity of Mn-peroxidase and peptidase, and an increase in the activity of C acquiring enzymes. Our results show that the rapid accumulation of C in the humus layer frequently observed in areas with high N deposition is consistent with a shift in microbial metabolism, where decomposition associated with organic N acquisition is downregulated when inorganic N forms are readily available.
Topics: Nitrogen; Soil; Carbon; Forests; Microbiota; Soil Microbiology
PubMed: 38325494
DOI: 10.1016/j.scitotenv.2024.170741 -
FEMS Microbiology Ecology Dec 2014The ectomycorrhizal fungus Cenococcum geophilum (Ascomycota, Dothideomycetes) forms black, round to irregular sclerotia in forest soils. Fungi that colonize the...
The ectomycorrhizal fungus Cenococcum geophilum (Ascomycota, Dothideomycetes) forms black, round to irregular sclerotia in forest soils. Fungi that colonize the sclerotia appear to affect sclerotia viability and may play an important role in the life history of Cenococcum. Some of the fungi could also affect nutrient cycling by decomposing Cenococcum sclerotia, which are melanized and recalcitrant to decay. We used a culture-based method to document the fungal communities growing inside surface-sterilized sclerotia that were collected from forest soils. Cenococcum was successfully isolated from 297 of 971 sclerotia whereas 427 sclerotia hosted fungi other than Cenococcum. DNA barcoding of the internal transcribed spacer rDNA followed by grouping at 97% sequence similarity yielded 85 operational taxonomic units (OTUs) that consisted primarily of Ascomycota (e.g. Chaetothyriales, Eurotiales, Helotiales, Pleosporales) and a few Basidiomycota and Mucoromycotina. Although most fungal OTUs were infrequently cultured, several OTUs such as members of Asterostroma, Cladophialophora, Oidiodendron, and Pleosporales were common and found across many sites. Our results suggest that Cenococcum sclerotia act as a substrate for diverse fungi. The occurrence of several OTUs in sclerotia across many sites suggests that these fungi may be active parasites of Cenococcum sclerotia or may preferentially use sclerotia as a nutrient source.
Topics: Ascomycota; Basidiomycota; Biodiversity; DNA, Ribosomal Spacer; Forests; Mycorrhizae; Sequence Analysis, DNA; Soil Microbiology; Trees
PubMed: 25229424
DOI: 10.1111/1574-6941.12428 -
Horticulture Research 2020Adventitious root (AR) formation is a unique feature of plant reproduction and plays a vital role in crop production as many horticultural and forestry plants are...
Adventitious root (AR) formation is a unique feature of plant reproduction and plays a vital role in crop production as many horticultural and forestry plants are propagated through cuttings. A growing number of reports have shown that microbes, particularly mycorrhizal fungi are able to promote AR formation, but the underlying mechanisms remain largely unclear. This study established an in vitro culture system and investigated AR formation in microcuttings of Lindl. inoculated with Barron Om19, an ericoid mycorrhizal fungus strain. Hormones and precursors involved in the biosynthesis of indole-3-acetic acid (IAA) in Om19 mycelium were analyzed. Om19 was able to produce a large quantity of tryptophan (Trp) and also indole-3-pyruvate (IPA) and IAA, indicating that IAA biosynthesis in Om19 could be through a Trp-dependent pathway. After inoculation of Om19, ARs were quickly formed in microcuttings. Symbiosis related genes were activated in ARs, and Om19 effectively colonized the roots. , a key gene in plant biosynthesis of IAA and genes involved in nitrogen (N) uptake and metabolism, phosphorus (P) uptake were highly upregulated. Plants absorbed significantly greater quantity of mineral nutrients, and their growth was substantially enhanced compared to the control plants without Om19 inoculation. A working model for Om19 enhanced AR formation was proposed. The rapid formation of ARs in cuttings could be due in part to the induction of IAA biosynthesized by Om19 and also attributed to Trp catalyzed biosynthesis of IAA in plants. AR formation, in turn, provided Om19 preferred sites for colonization. Our study suggested that in addition to promoting AR formation, Om19 could potentially be used as a new biofertilizer for enhancing production of ericaceous plants, such as blueberry, cranberry, and rhododendron.
PubMed: 32922812
DOI: 10.1038/s41438-020-00361-6