Patterns of distribution of microfungi in decomposing bog and fen plants

2004 ◽  
Vol 82 (5) ◽  
pp. 710-720 ◽  
Author(s):  
Markus N Thormann ◽  
Randolph S Currah ◽  
Suzanne E Bayley
Keyword(s):  
Fungal Communities ◽  
Tissue Quality ◽  
Tissue Concentrations ◽  
Carex Aquatilis ◽  
Dominant Plant Species ◽  
Sphagnum Fuscum ◽  
Salix Planifolia ◽  
Environmental Surface ◽  
Forested Bog ◽  
Fen Plants

The microfungal assemblages from the litter of the dominant vegetation of a forested bog and a riverine, sedge-dominated fen in southern boreal Alberta, Canada, were investigated over a 2-year period. Canonical correspondence analyses showed distinctly different fungal communities associated with litter of the dominant plant species of this bog (Sphagnum fuscum (Schimp.) Klinggr.) and fen (Carex aquatilis Wahlenb. leaves and rhizomes and Salix planifolia Pursh leaves and roots). Plant tissue quality variables, including total phosphorus and total nitrogen tissue concentrations, correlated most strongly with the fungal communities. In contrast, site-specific environmental (surface water chemical variables) and physical (peat and water temperatures, water level) variables were not correlated with the fungal communities of these five decomposing fen and bog plant litters. Of 93 identified fungal taxa, 25% occurred exclusively in the bog and 56% occurred exclusively in the fen. Eighteen species (19%) were common to the materials examined from both peatlands. Several species of (i) Aspergillus, Mortierella, and Oidiodendron were restricted to the Sphagnum litter in the bog, and species of (ii) Phialophora, Phialocephala, Fusarium, Dimorphospora foliicola, Monocillium constrictum, and several basidiomycetes were restricted to the Carex and Salix plant litters in the fen. These taxa constitute components of the bog and fen fungal communities, respectively.Key words: fungal communities, decomposition, bog, fen, canonical correspondence analysis (CCA).

Comparison of decomposition of belowground and aboveground plant litters in peatlands of boreal Alberta, Canada

2001 ◽  
Vol 79 (1) ◽  
pp. 9-22 ◽  
Author(s):  
Markus N Thormann ◽  
Suzanne E Bayley ◽  
Randolph S Currah
Keyword(s):  
Plant Production ◽  
Nutrient Concentrations ◽  
Surface Water Chemistry ◽  
Litter Bag ◽  
Carex Aquatilis ◽  
Mass Losses ◽  
Sphagnum Fuscum ◽  
Salix Planifolia ◽  
Total Plant ◽  
Forested Bog

Studies examining the decomposition rates of belowground plant tissues in peatlands are scarce despite the significant contribution these tissues make to total plant production. Therefore, we measured mass losses of Carex aquatilis Wahlenb. leaves and rhizomes and Salix planifolia Pursh leaves and roots in a rich, sedge-dominated fen and Sphagnum fuscum (Schimp.) Klinggr. plants in a forested bog using the litter bag technique over a 2-year period in southern boreal Alberta. After 2 years, mass losses of C. aquatilis rhizomes (75%) were significantly higher than those of C. aquatilis leaves and Salix planifolia leaves, which were similar to each other (54 and 48%, respectively). Sphagnum fuscum and Salix planifolia root mass losses also were similar to each other (21 and 29%, respectively), but they were significantly lower than those of the other three litter types. Different tissue nutrient concentrations as well as alkalinity- and phosphorus-related surface water chemistry variables correlated significantly with mass losses of different litter types; however, they alone did not explain all of the mass loss trends. The majority of sedge peat and carbon in the fen originates from C. aquatilis leaves (188 and 86 g·m-2, respectively), with the remainder originating from C. aquatilis rhizomes (102 and 47 g·m-2, respectively) after the first 2 years of decomposition. Conversely, the majority of Salix planifolia peat and carbon originates from its roots (33 and 16 g·m-2, respectively) and the remainder from its leaves (24 and 11 g·m-2, respectively) over the same period. After the first 2 years of decomposition, 150 g·m-2 of peat and 71 g·m-2 of carbon remained from the decomposing Sphagnum fuscum in the bog.Key words: bog, fen, mass losses, Carex aquatilis, Salix planifolia, Sphagnum fuscum.

Microcosm tests of the effects of temperature and microbial species number on the decomposition of Carex aquatilis and Sphagnum fuscum litter from southern boreal peatlands

2004 ◽  
Vol 50 (10) ◽  
pp. 793-802 ◽  
Author(s):  
Markus N Thormann ◽  
Suzanne E Bayley ◽  
Randolph S Currah
Keyword(s):  
Global Warming ◽  
Positive Feedback ◽  
Elevated Temperatures ◽  
Species Number ◽  
Peat Moss ◽  
Decomposition Rates ◽  
Carex Aquatilis ◽  
Boreal Peatlands ◽  
Sphagnum Fuscum

Increased decomposition rates in boreal peatlands with global warming might increase the release of atmospheric greenhouse gases, thereby producing a positive feedback to global warming. How temperature influences microbial decomposers is unclear. We measured in vitro rates of decomposition of senesced sedge leaves and rhizomes (Carex aquatilis), from a fen, and peat moss (Sphagnum fuscum), from a bog, at 14 and 20 °C by the three most frequently isolated fungi and bacteria from these materials. Decomposition rates of the bog litter decreased (5- to 17-fold) with elevated temperatures, and decomposition of the sedge litters was either enhanced (2- to 30-fold) or remained unaffected by elevated temperatures. The increased temperature regime always favoured fungal over bacterial decomposition rates (2- to 3-fold). Different physiological characteristics of these microbes suggest that fungi using polyphenolic polymers as a carbon source cause greater mass losses of these litters. Litter quality exerted a stronger influence on decomposition at elevated temperatures, as litter rich in nutrients decomposed more quickly than litter poorer in nutrients at higher temperatures (8.0%–25.7% for the sedge litters vs. 0.2% for the bryophyte litter). We conclude that not all peatlands may provide a positive feedback to global warming. Cautious extrapolation of our data to the ecosystem level suggests that decomposition rates in fens may increase and those in bogs may decrease under a global warming scenario.Key words: fungi, bacteria, decomposition, temperature, Sphagnum fuscum, Carex aquatilis, peatlands, climate change, microcosms.

Armillaria sinapina in herbaceous plant material from a peatland in Alberta, Canada

2001 ◽  
Vol 79 (5) ◽  
pp. 643-647 ◽  
Author(s):  
Markus N Thormann ◽  
Colin L Myrholm ◽  
Ken I Mallett
Keyword(s):  
Plant Material ◽  
Fragment Length Polymorphism ◽  
Organic Soil ◽  
Soil Horizon ◽  
Herbaceous Plant ◽  
Base Pairs ◽  
Plant Materials ◽  
Somatic Incompatibility ◽  
Carex Aquatilis ◽  
Salix Planifolia

Armillaria sinapina Bérubé & Dessureault mycelium was isolated once from living Carex aquatilis Wahlenb. rhizomes, twice from decomposing C. aquatilis leaves, and three times from decomposing Salix planifolia Pursh leaves in a southern boreal sedge-dominated fen in Alberta, Canada. Restriction fragment length polymorphism (RFLP) analyses of the IGS-1 region with the AluI restriction enzyme were used to identify the isolates, because conspicuous, epigeous basidiomes could not be found in or near the fen. During these analyses, two previously unpublished fragment patterns for A. sinapina were found, consisting of 399–240–135 base pairs (bp) and 399–240–183–135 bp. Interspecific somatic incompatibility and interfertility tests confirmed the identifications obtained from the RFLP analyses. This is the first report of an annulate species of Armillaria being actively involved in the colonization and decomposition of herbaceous plant material in an ecosystem having only an organic soil horizon. Surveys for species of Armillaria should be expanded to include peatlands and herbaceous plant materials, because they may serve as vast potential biomass and genetic diversity reservoirs for this genus.Key words: peatland, Carex rhizomes, Salix leaves, RFLP, interspecific somatic incompatibility, interfertility.

Experimentally altered rainfall regimes and host root traits affect grassland arbuscular mycorrhizal fungal communities

2019 ◽  
Author(s):  
Coline Deveautour ◽  
Suzanne Donn ◽  
Sally Power ◽  
Kirk Barnett ◽  
Jeff Powell
Keyword(s):  
Fungal Community ◽  
Community Assembly ◽  
Root Length ◽  
Specific Root Length ◽  
Root Traits ◽  
Arbuscular Mycorrhizal ◽  
Fungal Communities ◽  
Rainfall Regime ◽  
Precipitation Regimes ◽  
Rainfall Regimes

Future climate scenarios predict changes in rainfall regimes. These changes are expected to affect plants via effects on the expression of root traits associated with water and nutrient uptake. Associated microorganisms may also respond to these new precipitation regimes, either directly in response to changes in the soil environment or indirectly in response to altered root trait expression. We characterised arbuscular mycorrhizal (AM) fungal communities in an Australian grassland exposed to experimentally altered rainfall regimes. We used Illumina sequencing to assess the responses of AM fungal communities associated with four plant species sampled in different watering treatments and evaluated the extent to which shifts were associated with changes in root traits. We observed that altered rainfall regimes affected the composition but not the richness of the AM fungal communities, and we found distinctive communities in the increased rainfall treatment. We found no evidence of altered rainfall regime effects via changes in host physiology because none of the studied traits were affected by changes in rainfall. However, specific root length was observed to correlate with AM fungal richness, while concentrations of phosphorus and calcium in root tissue and the proportion of root length allocated to fine roots were correlated to community composition. Our study provides evidence that climate change and its effects on rainfall may influence AM fungal community assembly, as do plant traits related to plant nutrition and water uptake. We did not find evidence that host responses to altered rainfall drive AM fungal community assembly in this grassland ecosystem.

Temporal dynamics of mycorrhizal fungal communities and co-associations with grassland plant communities following experimental manipulation of rainfall

2019 ◽  
Author(s):  
Coline Deveautour ◽  
Sally Power ◽  
Kirk Barnett ◽  
Raul Ochoa-Hueso ◽  
Suzanne Donn ◽  
...  
Keyword(s):  
Community Composition ◽  
Plant Community ◽  
Plant Communities ◽  
Fungal Community ◽  
Mycorrhizal Fungi ◽  
Temporal Dynamics ◽  
Arbuscular Mycorrhizal ◽  
Fungal Communities ◽  
Plant Responses ◽  
Rainfall Regimes

Climate models project overall a reduction in rainfall amounts and shifts in the timing of rainfall events in mid-latitudes and sub-tropical dry regions, which threatens the productivity and diversity of grasslands. Arbuscular mycorrhizal fungi may help plants to cope with expected changes but may also be impacted by changing rainfall, either via the direct effects of low soil moisture on survival and function or indirectly via changes in the plant community. In an Australian mesic grassland (former pasture) system, we characterised plant and arbuscular mycorrhizal (AM) fungal communities every six months for nearly four years to two altered rainfall regimes: i) ambient, ii) rainfall reduced by 50% relative to ambient over the entire year and iii) total summer rainfall exclusion. Using Illumina sequencing, we assessed the response of AM fungal communities sampled from contrasting rainfall treatments and evaluated whether variation in AM fungal communities was associated with variation in plant community richness and composition. We found that rainfall reduction influenced the fungal communities, with the nature of the response depending on the type of manipulation, but that consistent results were only observed after more than two years of rainfall manipulation. We observed significant co-associations between plant and AM fungal communities on multiple dates. Predictive co-correspondence analyses indicated more support for the hypothesis that fungal community composition influenced plant community composition than vice versa. However, we found no evidence that altered rainfall regimes were leading to distinct co-associations between plants and AM fungi. Overall, our results provide evidence that grassland plant communities are intricately tied to variation in AM fungal communities. However, in this system, plant responses to climate change may not be directly related to impacts of altered rainfall regimes on AM fungal communities. Our study shows that AM fungal communities respond to changes in rainfall but that this effect was not immediate. The AM fungal community may influence the composition of the plant community. However, our results suggest that plant responses to altered rainfall regimes at our site may not be resulting via changes in the AM fungal communities.

Influence of Long-term Fertilizations on Nutrients and Fungal Communities in Typical Paddy Soil of South China

2017 ◽  
Vol 43 (2) ◽  
pp. 286 ◽  
Author(s):  
Dan-Mei CHEN ◽  
Ling YUAN ◽  
Jian-Guo HUANG ◽  
Jian-Hua JI ◽  
Hong-Qian HOU ◽  
...  
Keyword(s):  
South China ◽  
Paddy Soil ◽  
Fungal Communities

Periocular Tissue Concentrations of Propranolol after Ocular Instillation of a Gel-Forming Solution

2016 ◽  
Vol 13 (7) ◽  
pp. 1144-1151
Author(s):  
Michael B. Yang ◽  
Hongzhuo Liu ◽  
S. Kevin Li ◽  
Jinsong Hao
Keyword(s):  
Tissue Concentrations

scholarly journals Fungal Diversity in the Phyllosphere of Pinus heldreichii H. Christ—An Endemic and High-Altitude Pine of the Mediterranean Region

Diversity ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 172 ◽  
Author(s):  
Jelena Lazarević ◽  
Audrius Menkis
Keyword(s):  
High Altitude ◽  
Bark Beetles ◽  
Fungal Pathogens ◽  
High Throughput Sequencing ◽  
Fungal Communities ◽  
High Quality ◽  
The Balkans ◽  
Fungal Community Structure ◽  
Growing Conditions ◽  
Coniferous Tree Species

Pinus heldreichii is a high-altitude coniferous tree species naturaly occurring in small and disjuncted populations in the Balkans and southern Italy. The aim of this study was to assess diversity and composition of fungal communities in living needles of P. heldreichii specifically focusing on fungal pathogens. Sampling was carried out at six different sites in Montenegro, where 2-4 year-old living needles of P. heldreichii were collected. Following DNA isolation, it was amplified using ITS2 rDNA as a marker and subjected to high-throughput sequencing. Sequencing resulted in 31,831 high quality reads, which after assembly were found to represent 375 fungal taxa. The detected fungi were 295 (78.7%) Ascomycota, 79 (21.0%) Basidiomycota and 1 (0.2%) Mortierellomycotina. The most common fungi were Lophodermium pinastri (12.5% of all high-quality sequences), L. conigenum (10.9%), Sydowia polyspora (8.8%), Cyclaneusma niveum (5.5%), Unidentified sp. 2814_1 (5.4%) and Phaeosphaeria punctiformis (4.4%). The community composition varied among different sites, but in this respect two sites at higher altitudes (harsh growing conditions) were separated from three sites at lower altitudes (milder growing conditions), suggesting that environmental conditions were among major determinants of fungal communities associated with needles of P. heldreichii. Trees on one study site were attacked by bark beetles, leading to discolouration and frequent dieback of needles, thereby strongly affecting the fungal community structure. Among all functional groups of fungi, pathogens appeared to be an important component of fungal communities in the phyllosphere of P. heldreichii, especially in those trees under strong abiotic and biotic stress.

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