ORCID Profile
0000-0003-1091-2452
Current Organisation
Western Sydney University
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Research Topics
In Research Link Australia (RLA), "Research Topics" refer to ANZSRC FOR and SEO codes. These topics are either sourced from ANZSRC FOR and SEO codes listed in researchers' related grants or generated by a large language model (LLM) based on their publications.
Top 5 Research Topics
ANZSRC Field of Research (FoR)
Mycology | Microbiology | Soil Biology | Environmental Technologies | Fertilisers and Agrochemicals (Application etc.) | Environmental Engineering | Community Ecology |
ANZSRC Socio-Economic Objective (SEO)
Forest and Woodlands Flora, Fauna and Biodiversity | Sparseland, Permanent Grassland and Arid Zone Flora, Fauna and Biodiversity | Farmland, Arable Cropland and Permanent Cropland Soils | Forest and Woodlands Soils | Organic Fertilisers | Farmland, Arable Cropland and Permanent Cropland Flora, Fauna and Biodiversity | Expanding Knowledge in Technology
Related Links
Publications
When to cut your losses: Dispersal allocation in an asexual filamentous fungus in response to competition
Publisher: Wiley
Date: 12-03-2019
DOI: 10.1002/ECE3.5041
Extraction and Purification of DNA from Wood at Various Stages of Decay for Metabarcoding of Wood-Associated Fungi
Publisher: Springer US
Date: 08-11-2021
Variations in nitrogen use efficiency reflect the biochemical subtype while variations in water use efficiency reflect the evolutionary lineage of C4 grasses at inter-glacial CO2
Publisher: Wiley
Date: 21-12-2016
DOI: 10.1111/PCE.12636
Abstract: C4 photosynthesis evolved multiple times in erse lineages. Most physiological studies comparing C4 plants were not conducted at the low atmospheric CO2 prevailing during their evolution. Here, 24 C4 grasses belonging to three biochemical subtypes [nicotinamide adenine dinucleotide malic enzyme (NAD-ME), phosphoenolpyruvate carboxykinase (PCK) and nicotinamide adenine dinucleotide phosphate malic enzyme (NADP-ME)] and six major evolutionary lineages were grown under ambient (400 μL L(-1) ) and inter-glacial (280 μL L(-1) ) CO2 . We hypothesized that nitrogen-related and water-related physiological traits are associated with subtypes and lineages, respectively. Photosynthetic rate and stomatal conductance were constrained by the shared lineage, while variation in leaf mass per area (LMA), leaf N per area, plant dry mass and plant water use efficiency were influenced by the subtype. Subtype and lineage were equally important for explaining variations in photosynthetic nitrogen use efficiency (PNUE) and photosynthetic water use efficiency (PWUE). CO2 treatment impacted most parameters. Overall, higher LMA and leaf N distinguished the Chloridoideae/NAD-ME group, while NADP-ME and PCK grasses were distinguished by higher PNUE regardless of lineage. Plants were characterized by high photosynthesis and PWUE when grown at ambient CO2 and by high conductance at inter-glacial CO2 . In conclusion, the evolutionary and biochemical ersity among C4 grasses was aligned with discernible leaf physiology, but it remains unknown whether these traits represent ecophysiological adaptation.
Improved Phytophthora resistance in commercial chickpea (Cicer arietinum ) varieties negatively impacts symbiotic gene signalling and symbiotic potential in some var
Publisher: Wiley
Date: 04-06-2016
DOI: 10.1111/PCE.12757
Abstract: Breeding disease-resistant varieties is one of the most effective and economical means to combat soilborne diseases in pulse crops. Commonalities between pathogenic and mutualistic microbe colonization strategies, however, raises the concern that reduced susceptibility to pathogens may simultaneously reduce colonization by beneficial microbes. We investigate here the degree of overlap in the transcriptional response of the Phytophthora medicaginis susceptible chickpea variety 'Sonali' to the early colonization stages of either Phytophthora, rhizobial bacteria or arbuscular mycorrhizal fungi. From a total of 6476 genes differentially expressed in Sonali roots during colonization by any of the microbes tested, 10.2% were regulated in a similar manner regardless of whether it was the pathogenic oomycete or a mutualistic microbe colonizing the roots. Of these genes, 49.7% were oppositely regulated under the same conditions in the moderately Phytophthora resistant chickpea variety 'PBA HatTrick'. Chickpea varieties with improved resistance to Phytophthora also displayed lower colonization by rhizobial bacteria and mycorrhizal fungi leading to an increased reliance on N and P from soil. Together, our results suggest that marker-based breeding in crops such as chickpea should be further investigated such that plant disease resistance can be tailored to a specific pathogen without affecting mutualistic plant:microbe interactions.
Initial wood trait variation overwhelms endophyte community effects for explaining decay trajectories
Publisher: Wiley
Date: 25-02-2022
Abstract: Microbial organisms, environmental conditions and their interactions govern many ecosystem processes. Recent studies have highlighted the importance of priority effects, that is, the identity of potential decomposers present early in community assembly, in determining resulting decay rates especially for wood. In erse forests, available woody substrates differ chemically and structurally with implications for their role as both habitats and resources for microbes. Both wood traits and microbial communities at the start of the decay process affect subsequent decay rates, but the relative magnitude of effects is not known. In this work, we sought to ask a simple question: what are the relative effects of microbial communities and wood traits? We characterized fungal and oomycete endophytes with licon sequencing from stems of 22 woody species growing in woodlands near Richmond, NSW, Australia, and measured 11 traits to capture variation in the physical and chemical wood substrates. To evaluate the consequence of endophyte ersity and wood traits on the trajectory of decay, stem s les were sequentially harvested over 5 years to quantify the decay rate, its consistency and how it varies through time. We did not find evidence to support particular initial endophyte compositions leading to faster decay. Instead, initial wood attributes were much more powerful in explaining decay trajectories with smaller, less dense stems with high water, low N and low lignin concentrations decomposing consistently faster. These data show that initial wood traits have long‐lasting consequences on decay unlike natural variation in endophyte communities, supporting the idea that community member functions are highly redundant. Wood substrate‐driven environmental filtering, rather than endophyte‐driven priority effects, had a stronger effect on decay when real‐world levels of ersity in wood traits were considered. Read the free Plain Language Summary for this article on the Journal blog.
Integrated analysis of aboveground and belowground indicators support a comprehensive evaluation of ecosystem recovery
Publisher: Wiley
Date: 30-07-2023
DOI: 10.1111/REC.13987
Abstract: Analyses of erse aboveground and belowground indicators should underpin assessments of ecosystem recovery, yet monitoring many indicators is costly and their integration is challenging. Our objective was to combine indicators through a Bayesian hierarchical model to provide a comprehensive assessment of ecosystem status and identify a cost‐effective subset of indicators to provide an accurate estimate of ecosystem recovery. We assessed 59 aboveground–belowground indicators, classified into nine components of composition, structure, and function, to estimate the ecosystem status of restored rock spoils and reference forests in south‐eastern Australia. Overall ecosystem status, which integrates across ecosystem components and supporting indicators, was lower within restored forests but positively correlated with forest age. Reference forests had greater aboveground and belowground biotic structure, organic matter supply, and soil carbon stability, and trends were consistent among all of their supporting indicators. A subset of organic matter quality and nutrient cycling indicators were greater within restored forests, suggesting high ecosystem process rates, but that soil carbon may be more vulnerable to loss. Aboveground biotic structure was correlated with organic matter supply and quality, stability of soil carbon, the cycling of nutrients, and belowground biotic structure, providing evidence of aboveground–belowground coupling. A combination of four indicators representing belowground biotic structure, soil carbon stability, organic matter supply, and aboveground composition, provided a good estimate of ecosystem status at a third of the cost. Although ecosystem status can be monitored with a small set of indicators, a ersity of aboveground–belowground indicators provide a robust and comprehensive assessment of recovery.
Pedobiologia in 2015: The International Year of Soils
Publisher: Elsevier BV
Date: 03-2015
Triggering dieback in an invasive plant: endophyte diversity and pathogenicity
Publisher: Springer Science and Business Media LLC
Date: 04-02-2017
Ecological stoichiometry and fungal community turnover reveal variation among mycorrhizal partners in their responses to warming and drought
Publisher: Wiley
Date: 30-11-2023
DOI: 10.1111/MEC.16278
Abstract: Symbiotic fungi mediate important energy and nutrient transfers in terrestrial ecosystems. Environmental change can lead to shifts in communities of symbiotic fungi, but the consequences of these shifts for nutrient dynamics among symbiotic partners are poorly understood. Here, we assessed variation in carbon (C), nitrogen (N) and phosphorus (P) in tissues of arbuscular mycorrhizal (AM) fungi and a host plant ( Medicago sativa ) in response to experimental warming and drought. We linked compositional shifts in AM fungal communities in roots and soil to variation in hyphal chemistry by using high‐throughput DNA sequencing and joint species distribution modelling. Compared to plants, AM hyphae was 43% lower in (C) and 24% lower in (N) but more than nine times higher in (P), with significantly lower C:N, C:P and N:P ratios. Warming and drought resulted in increases in (P) and reduced C:P and N:P ratios in all tissues, indicating fungal P accumulation was exacerbated by climate‐associated stress. Warming and drought modified the composition of AM fungal communities, and many of the AM fungal genera that were linked to shifts in mycelial chemistry were also negatively impacted by climate variation. Our study offers a unified framework to link climate change, fungal community composition, and community‐level functional traits. Thus, our study provides insight into how environmental change can alter ecosystem functions via the promotion or reduction of fungal taxa with different stoichiometric characteristics and responses.
Symbiotic status alters fungal eco‐evolutionary offspring trajectories
Publisher: Wiley
Date: 17-06-2023
DOI: 10.1111/ELE.14271
Abstract: Despite host‐fungal symbiotic interactions being ubiquitous in all ecosystems, understanding how symbiosis has shaped the ecology and evolution of fungal spores that are involved in dispersal and colonization of their hosts has been ignored in life‐history studies. We assembled a spore morphology database covering over 26,000 species of free‐living to symbiotic fungi of plants, insects and humans and found more than eight orders of variation in spore size. Evolutionary transitions in symbiotic status correlated with shifts in spore size, but the strength of this effect varied widely among phyla. Symbiotic status explained more variation than climatic variables in the current distribution of spore sizes of plant‐associated fungi at a global scale while the dispersal potential of their spores is more restricted compared to free‐living fungi. Our work advances life‐history theory by highlighting how the interaction between symbiosis and offspring morphology shapes the reproductive and dispersal strategies among living forms.
Determinants of root‐associated fungal communities within A steraceae in a semi‐arid grassland
Publisher: Wiley
Date: 11-12-2013
Increases in aridity lead to drastic shifts in the assembly of dryland complex microbial networks
Publisher: Wiley
Date: 23-12-2019
DOI: 10.1002/LDR.3453
Roundup Ready®soybean gene concentrations in field soil aggregate size classes
Publisher: Oxford University Press (OUP)
Date: 02-2009
DOI: 10.1111/J.1574-6968.2008.01449.X
Abstract: Roundup Ready (RR) soybeans containing recombinant Agrobacterium spp. CP4 5-enol-pyruvyl-shikimate-3-phosphate synthase (cp4 epsps) genes tolerant to the herbicide glyphosate are extensively grown worldwide. The concentration of recombinant DNA from RR soybeans in soil aggregates was studied due to the possibility of genetic transformation of soil bacteria. This study used real-time PCR to examine the concentration of cp4 epsps in four field soil aggregate size classes (>2000 microm, 2000-500 microm, 500-250 microm and 2000 mum fraction contained between 66.62% and 99.18% of total gene copies, although it only accounted for about 30.00% of the s led soil. Aggregate formation may facilitate persistence of recombinant DNA.
Indigenous Arbuscular Mycorrhizal Fungal Assemblages Protect Grassland Host Plants from Pathogens
Publisher: Public Library of Science (PLoS)
Date: 16-11-2011
Is it time to include legumes in plant silicon research?
Publisher: Wiley
Date: 10-04-2020
A review of peer-review for Pedobiologia – Journal of Soil Ecology
Publisher: Elsevier BV
Date: 11-2019
Quantitation of Transgenic Plant DNA in Leachate Water: Real-Time Polymerase Chain Reaction Analysis
Publisher: American Chemical Society (ACS)
Date: 29-06-2005
DOI: 10.1021/JF0504667
Abstract: Roundup Ready (RR) genetically modified (GM) corn and soybean comprise a large portion of the annual planted acreage of GM crops. Plant growth and subsequent plant decomposition introduce the recombinant DNA (rDNA) into the soil environment, where its fate has not been completely researched. Little is known of the temporal and spatial distribution of plant-derived rDNA in the soil environment and in situ transport of plant DNA by leachate water has not been studied before. The objectives of this study were to determine whether sufficient quantities of plant rDNA were released by roots during growth and early decomposition to be detected in water collected after percolating through a soil profile and to determine the influence of temperature on DNA persistence in the leachate water. In idual plants of RR corn and RR soybean were grown in modified cylinders in a growth room, and the cylinders were flushed with rain water weekly. Immediately after collection, the leachate was subjected to DNA purification followed by rDNA quantification using real-time Polymerase Chain Reaction (PCR) analysis. To test the effects of temperature on plant DNA persistence in leachate water, water s les were spiked with known quantities of RR soybean or RR corn genomic DNA and DNA persistence was examined at 5, 15, and 25 degrees C. Differences in the amounts and temporal distributions of root-derived rDNA were observed between corn and soybean plants. The results suggest that rainfall events may distribute plant DNA throughout the soil and into leachate water. Half-lives of plant DNA in leachate water ranged from 1.2 to 26.7 h, and persistence was greater at colder temperatures (5 and 15 degrees C).
Towards robust and repeatable sampling methods in eDNA-based studies.
Publisher: Wiley
Date: 14-06-2018
Abstract: DNA-based techniques are increasingly used for measuring the bio ersity (species presence, identity, abundance and community composition) of terrestrial and aquatic ecosystems. While there are numerous reviews of molecular methods and bioinformatic steps, there has been little consideration of the methods used to collect s les upon which these later steps are based. This represents a critical knowledge gap, as methodologically sound field s ling is the foundation for subsequent analyses. We reviewed field s ling methods used for metabarcoding studies of both terrestrial and freshwater ecosystem bio ersity over a nearly three-year period (n = 75). We found that 95% (n = 71) of these studies used subjective s ling methods and inappropriate field methods and/or failed to provide critical methodological information. It would be possible for researchers to replicate only 5% of the metabarcoding studies in our s le, a poorer level of reproducibility than for ecological studies in general. Our findings suggest greater attention to field s ling methods, and reporting is necessary in eDNA-based studies of bio ersity to ensure robust outcomes and future reproducibility. Methods must be fully and accurately reported, and protocols developed that minimize subjectivity. Standardization of s ling protocols would be one way to help to improve reproducibility and have additional benefits in allowing compilation and comparison of data from across studies.
Phosphorus availability and arbuscular mycorrhizal fungi limit soil C cycling and influence plant responses to elevated CO2 conditions
Publisher: Springer Science and Business Media LLC
Date: 07-06-2022
Pastures and Climate Extremes: Impacts of cool season warming and drought on the productivity of key pasture species in a field experiment
Publisher: Cold Spring Harbor Laboratory
Date: 22-12-2020
DOI: 10.1101/2020.12.21.423155
Abstract: Shifts in the timing, intensity and/or frequency of climate extremes, such as severe drought and heatwaves, can generate sustained shifts in ecosystem function with important ecological and economic impacts for rangelands and managed pastures. The Pastures and Climate Extremes experiment (PACE) in Southeast Australia was designed to investigate the impacts of a severe winter/spring drought (60% rainfall reduction) and, for a subset of species, a factorial combination of drought and elevated temperature (ambient +3 °C) on pasture productivity. The experiment included nine common pasture and Australian rangeland species from three plant functional groups (C 3 grasses, C 4 grasses and legumes) planted in monoculture. Winter/spring drought resulted in productivity declines of 45% on average and up to 74% for the most affected species ( Digitaria eriantha ) during the 6-month treatment period, with eight of the nine species exhibiting significant yield reductions. Despite considerable variation in species’ sensitivity to drought, C 4 grasses were more strongly affected by this treatment than C 3 grasses or legumes. Warming also had negative effects on cool-season productivity, associated at least partially with exceedance of optimum growth temperatures in spring and indirect effects on soil water content. The combination of winter/spring drought and year-round warming resulted in the greatest yield reductions. We identified responses that were either additive such that there was only as significant warming effect under drought ( Festuca ), or less-than-additive, where there was no drought effect under warming ( Medicago ), compared to ambient plots. Results from this study highlight the sensitivity of erse pasture species to increases in winter and spring drought severity similar to those predicted for this region, and that anticipated benefits of cool-season warming are unlikely to be realised. Overall, the substantial negative impacts on productivity suggest that future, warmer, drier climates will result in shortfalls in cool-season forage availability, with profound implications for the livestock industry and natural grazer communities.
Elevated CO2 does not increase eucalypt forest productivity on a low-phosphorus soil
Publisher: Springer Science and Business Media LLC
Date: 06-03-2017
DOI: 10.1038/NCLIMATE3235
Interguild antagonism between biological controls: impact of entomopathogenic nematode application on an aphid predator, Aphidoletes aphidimyza (Diptera: Cecidomyiidae)
Publisher: Elsevier BV
Date: 05-2004
The Recycling Endosome Protein Rab17 Regulates Melanocytic Filopodia Formation and Melanosome Trafficking
Publisher: Wiley
Date: 25-02-2011
DOI: 10.1111/J.1600-0854.2011.01172.X
Abstract: Rab GTPases including Rab27a, Rab38 and Rab32 function in melanosome maturation or trafficking in melanocytes. A screen to identify additional Rabs involved in these processes revealed the localization of GFP-Rab17 on recycling endosomes (REs) and melanosomes in melanocytic cells. Rab17 mRNA expression is regulated by microphthalmia transcription factor (MITF), a characteristic of known pigmentation genes. Rab17 siRNA knockdown in melanoma cells quantitatively increased melanosome concentration at the cell periphery. Rab17 knockdown did not inhibit melanosome maturation nor movement, but it caused accumulation of melanin inside cells. Double knockdown of Rab17 and Rab27a indicated that Rab17 acts on melanosomes downstream of Rab27a. Filopodia are known to play a role in melanosome transfer, and in Rab17 knockdown cells filopodia formation was inhibited. Furthermore, we show that stimulation of melanoma cells with α-melanocyte-stimulating hormone induces filopodia formation, supporting a role for filopodia in melanosome release. Cell stimulation also caused redistribution of REs to the periphery, and knockdown of additional RE-associated Rabs 11a and 11b produced a similar accumulation of melanosomes and melanin to that seen after loss of Rab17. Our findings reveal new functions for RE and Rab17 in pigmentation through a distal step in the process of melanosome release via filopodia.
Assembly processes lead to divergent soil fungal communities within and among 12 forest ecosystems along a latitudinal gradient
Publisher: Wiley
Date: 06-06-2021
DOI: 10.1111/NPH.17457
Abstract: Latitudinal gradients provide opportunities to better understand soil fungal community assembly and its relationship with vegetation, climate, soil and ecosystem function. Understanding the mechanisms underlying community assembly is essential for predicting compositional responses to changing environments. We quantified the relative importance of stochastic and deterministic processes in structuring soil fungal communities using patterns of community dissimilarity observed within and between 12 natural forests and related these to environmental variation within and among sites. The results revealed that whole fungal communities and communities of arbuscular and ectomycorrhizal fungi consistently exhibited ergent patterns but with less ergence for ectomycorrhizal fungi at most sites. Within those forests, no clear relationships were observed between the degree of ergence within fungal and plant communities. When comparing communities at larger spatial scales, among the 12 forests, we observed distinct separation in all three fungal groups among tropical, subtropical and temperate climatic zones. Soil fungal β‐ ersity patterns between forests were also greater when comparing forests exhibiting high environmental heterogeneity. Taken together, although large‐scale community turnover could be attributed to specific environmental drivers, the differences among fungal communities in soils within forests was high even at local scales.
High habitat-specificity in fungal communities in oligo-mesotrophic, temperate Lake Stechlin (North-East Germany)
Publisher: Pensoft Publishers
Date: 21-10-2016
The role of stochasticity differs in the assembly of soil- and root-associated fungal communities
Publisher: Elsevier BV
Date: 2015
A critique of studies evaluating glyphosate effects on diseases associated with Fusarium spp.
Publisher: Wiley
Date: 08-07-2008
Microbial functional diversity enhances predictive models linking environmental parameters to ecosystem properties
Publisher: Wiley
Date: 07-2015
DOI: 10.1890/14-1127.1
Abstract: Microorganisms drive biogeochemical processes, but linking these processes to real changes in microbial communities under field conditions is not trivial. Here, we present a model-based approach to estimate independent contributions of microbial community shifts to ecosystem properties. The approach was tested empirically, using denitrification potential as our model process, in a spatial survey of arable land encompassing a range of edaphic conditions and two agricultural production systems. Soil nitrate was the most important single predictor of denitrification potential (the change in Akaike's information criterion, corrected for s le size, ΔAIC(c) = 20.29) however, the inclusion of biotic variables (particularly the evenness and size of denitrifier communities [ΔAIC(c) = 12.02], and the abundance of one denitrifier genotype [ΔAIC(c) = 18.04]) had a substantial effect on model precision, comparable to the inclusion of abiotic variables (biotic R2 = 0.28, abiotic R2 = 0.50, biotic + abiotic R2 = 0.76). This approach provides a valuable tool for explicitly linking microbial communities to ecosystem functioning. By making this link, we have demonstrated that including aspects of microbial community structure and ersity in biogeochemical models can improve predictions of nutrient cycling in ecosystems and enhance our understanding of ecosystem functionality.
Soil chemistry and fungal communities are associated with dieback in an Endangered Australian shrub
Publisher: Springer Science and Business Media LLC
Date: 10-2023
DOI: 10.1007/S11104-022-05724-7
Abstract: Field surveys across known populations of the Endangered Persoonia hirsuta (Proteaceae) in 2019 suggested the soil environment may be associated with dieback in this species. To explore how characteristics of the soil environment (e.g., pathogens, nutrients, soil microbes) relate to dieback, a soil bioassay (Experiment 1) was conducted using field soils from two dieback effected P. hirsuta populations. Additionally, a nitrogen addition experiment (Experiment 2) was conducted to explore how the addition of soil nitrogen impacts dieback. The field soils were baited for pathogens, and soil physiochemical and microbial community characteristics were assessed and related to dieback among plants in the field and nursery-grown plants inoculated with the same field soils. Roots from inoculated plants were harvested to confirm the presence of soil pathogens and root-associated endophytes. Using these isolates, a dual culture antagonism assay was performed to examine competition among these microbes and identify candidate pathogens or pathogen antagonists. Dieback among plants in the field and Experiment 1 was associated with soil physiochemical properties (nitrogen and potassium), and soil microbes were identified as significant indicators of healthy and dieback-affected plants. Plants in Experiment 2 exhibited greater dieback when treated with elevated nitrogen. Additionally, post-harvest culturing identified fungi and other soil pathogens, some of which exhibited antagonistic behavior. This study identified candidate fungi and soil physiochemical properties associated with observed dieback and dieback resistance in an Endangered shrub and provides groundwork for further exploring what drives dieback and how it can be managed to promote the conservation of wild populations.
Distinguishing Defensive Characteristics in the Phloem of Ash Species Resistant and Susceptible to Emerald Ash Borer
Publisher: Springer Science and Business Media LLC
Date: 05-2011
DOI: 10.1007/S10886-011-9954-Z
Abstract: We examined the extent to which three Fraxinus cultivars and a wild population that vary in their resistance to Emerald Ash Borer (EAB) could be differentiated on the basis of a suite of constitutive chemical defense traits in phloem extracts. The EAB-resistant Manchurian ash (F. mandshurica, cv. Mancana) was characterized by having a rapid rate of wound browning, a high soluble protein concentration, low trypsin inhibitor activities, and intermediate levels of peroxidase activity and total soluble phenolic concentration. The EAB-susceptible white ash (F. americana, cv. Autumn Purple) was characterized by a slow wound browning rate and low levels of peroxidase activity and total soluble phenolic concentrations. An EAB-susceptible green ash cultivar (F. pennsylvanica, cv. Patmore) and a wild accession were similar to each other on the basis of several chemical defense traits, and were characterized by high activities of peroxidase and trypsin inhibitor, a high total soluble phenolic concentration, and an intermediate rate of wound browning. Lignin concentration and polyphenol oxidase activities did not differentiate resistant and susceptible species. Of 33 phenolic compounds separated by HPLC and meeting a minimum criterion for analysis, nine were unique to Manchurian ash, five were shared among all species, and four were found in North American ashes and not in the Manchurian ash. Principal components analysis revealed clear separations between Manchurian, white, and green ashes on the basis of all phenolics, as well as clear separations on the basis of quantities of phenolics that all species shared. Variation in some of these constitutive chemical defense traits may contribute to variation in resistance to EAB in these species.
Myristate and the ecology of AM fungi: significance, opportunities, applications and challenges
Publisher: Wiley
Date: 09-04-2020
DOI: 10.1111/NPH.16527
Intraspecific competition between ectomycorrhizal Pisolithus microcarpus isolates impacts plant and fungal performance under elevated CO2 and temperature
Publisher: Oxford University Press (OUP)
Date: 23-05-2016
Abstract: Root systems are simultaneously colonized by multiple in iduals of mycorrhizal fungi. Intraspecific competitive interactions between fungal isolates are likely to affect both fungal and plant performance and be influenced by abiotic factors. Here, we assessed the impact of intraspecific competition between three Pisolithus microcarpus isolates on the establishment of, and benefit derived from, symbioses with Eucalyptus grandis seedlings. We investigated the outcomes of competition under ambient and elevated temperature and CO2 concentration ([CO2]) in a factorial design. We observed a reduction in mycelium growth, mycorrhiza formation and seedling mass when two P. microcarpus isolates were co-inoculated on a single E. grandis seedling. Isolates invested more in mycelium than in mycorrhizas in the presence of a competitor. All isolates responded negatively to elevated [CO2] and positively to elevated temperature, which led to no changes on the outcomes of the interactions with changing conditions. However, the presence of a competitor hindered the positive response of P. microcarpus isolates to warming, which resulted in larger negative effects of competition under elevated temperature than under ambient conditions. Our study highlights the need to consider how competition affects in idual fungal responses as well as plant performance when trying to predict the impacts of climate change.
Metabarcoding mites: Three years of elevated CO2 has no effect on oribatid assemblages in a Eucalyptus woodland
Publisher: Elsevier BV
Date: 09-2020
Soil physico-chemical properties are critical for predicting carbon storage and nutrient availability across Australia
Publisher: IOP Publishing
Date: 09-2020
Abstract: Soil carbon and nutrient availability play crucial roles in ecosystem sustainability, and they are controlled by the interaction of climatic, biotic, and soil physico-chemical variables. Although soil physico-chemical properties have been recognized as vital variables for predicting soil organic carbon (SOC) and nutrients, their relative influence across broad geographical scales has yet to be evaluated when simultaneously considering many other drivers. Using boosted regression tree and structural equation modelling analyses of observations from topsoil (0–10 cm) and subsoil (20–30 cm) at 628 sites across Australia, we investigated the effects and relative influence of climate (mean annual temperature and aridity index), plant productivity, soil bio ersity (bacterial and fungal richness), and soil physical (clay and silt) and chemical (pH and iron) properties on SOC content and nutrient availability (i.e. nitrogen, phosphorus, and potassium). Among these variables, we found that soil physico-chemical properties primarily predicted the continent-scale SOC storage and nutrient availability. In contrast, climate, plant productivity, and soil bio ersity played relatively small roles. The importance of physico-chemical properties was evident across soil depths and ecosystem types (i.e. tropical, temperate, arid, and cropland). Our findings point to the need to better understand the role of soil physico-chemical properties in soil carbon and nutrient cycling and including these variables in predictions of SOC and nutrient dynamics at the ecosystem to continental scale.
How novel are the chemical weapons of garlic mustard in North American forest understories?
Publisher: Springer Science and Business Media LLC
Date: 14-03-2010
Interactions between silicon and alkaloid defences in endophyte‐infected grasses and the consequences for a folivore
Publisher: Wiley
Date: 09-11-2021
Abstract: Grasses have developed a wide range of morphological and physiological mechanisms to resist herbivory. For instance, they accumulate silicon (Si) in tissue, as physical defence, and associate symbiotically with foliar Epichloë ‐endophytes that provide chemical defence via antiherbivore alkaloids. Recent evidence showed that some Epichloë ‐endophytes increase foliar Si in forage grasses however, whether this impacts insect herbivores is unknown. Furthermore, while Si is primarily a physical defence, it also affects production of plant defensive secondary metabolites Si supply might therefore affect Epichloë ‐alkaloids, although this remains untested. We grew endophyte‐free (Nil) and Epichloë ‐infected tall fescue and perennial ryegrass in a factorial combination with or without Si supplementation, in the absence or presence of Helicoverpa armigera . Epichloë ‐endophyte strains were AR584 for tall fescue, and AR37, AR1 or Wild‐type (WT) for perennial ryegrass. We assessed how Si supply and Epichloë ‐endophytes in interaction with herbivory affected foliar Si and mutualist‐derived alkaloid concentrations. Subsequently, their effects on H. armigera relative growth rates (RGRs) were evaluated. Endophytes generally increased Si concentrations in Si‐supplied plants. In tall fescue AR584 and perennial ryegrass AR37, endophytes increased constitutive (herbivore‐free) and induced (herbivore‐inoculated) Si concentrations by at least 25% in contrast, in perennial ryegrass, the AR1 endophyte only increased constitutive levels. Si supply did not affect alkaloids produced by AR584 or AR1/WT endophytes however, in the presence of herbivory, Si supply decreased the induction of alkaloids produced by AR37 endophytes by 33%. For tall fescue, Si supply reduced H. armigera RGR by at least 76%, regardless of endophytic status, whereas, endophyte‐alkaloids played a secondary role only reducing herbivore growth in the absence of Si supply. Conversely, in perennial ryegrass, both Si and endophyte‐alkaloids (regardless of Si supply) reduced herbivore RGR although not synergised. Novel interactions between constitutive and induced Si‐ and alkaloid‐based antiherbivore defences in grasses were observed. Overall, Si had a greater effect on the folivore than endophytes in both grasses. Endophyte defences contributed more to herbivore resistance in perennial ryegrass than tall fescue. We demonstrate that Si and endophytes were not antagonistic and highlight that the protective nature of their interaction varies with the grass‐endophyte species tested. A free Plain Language Summary can be found within the Supporting Information of this article.
Response of belowground communities to short-term phosphorus addition in a phosphorus-limited woodland
Publisher: Springer Science and Business Media LLC
Date: 12-03-2015
Delving into the dark ecology: A continent-wide assessment of patterns of composition in soil fungal communities from Australian tussock grasslands
Publisher: Elsevier BV
Date: 06-2019
A soil fungal metacommunity perspective reveals stronger and more localised interactions above the tree line of an alpine/subalpine ecotone
Publisher: Elsevier BV
Date: 08-2019
Endophyte community composition is associated with dieback occurrence in an invasive tree
Publisher: Springer Science and Business Media LLC
Date: 10-06-2016
Silicon enrichment alters functional traits in legumes depending on plant genotype and symbiosis with nitrogen‐fixing bacteria
Publisher: Wiley
Date: 27-09-2021
Abstract: Silicon (Si) uptake and deposition (silicification) in tissues is known to alleviate stresses and generally improve plant health. This is mostly studied in Si‐high accumulators, such as grasses, with comparatively less known about its effects on other plant functional groups, such as legumes. There is speculation that Si may positively impact the symbiosis between legumes and the nitrogen‐fixing bacteria (rhizobia) they associate with, but this is poorly understood. This study examined the effects of Si enrichment on legume species associated with rhizobia and the potential underlying mechanism of Si impacts. We conducted a glasshouse experiment with lucerne Medicago sativa and barrel medic M. truncatula associated with a model rhizobial strain. Six genotypes (three per species) were either supplemented with Si (+Si) or untreated (−Si). We quantified 16 functional traits which could be classified as plant growth, physiology, elemental chemistry, nodule activity and nitrogen fixation. The two legume species responded to Si distinctively. For ex le, Si supplementation increased shoot biomass by more than 10% in lucerne but growth was unaffected in barrel medic. Conversely, nitrogen‐fixing enzyme (nitrogenase) activity was promoted by more than 85% in +Si barrel medic plants but not in lucerne. Moreover, Si supplementation of lucerne increased the concentrations of Si in leaves by more than 36% but not in root nodules. Increased foliar concentrations of Si in lucerne were positively associated with increased shoot and root biomass in Sequel and Trifecta genotypes, respectively. Conversely, Si supplementation of barrel medic increased the concentration of Si in root nodules by 29% but not that in foliar tissues. Nitrogenase activity and where silicification occurred, differed between genotypes in barrel medic nitrogenase activity was correlated with concentrations of Si in root nodules rather than that in foliar tissues in one genotype (Sephi) but the reverse was true in another (Hannaford). This study demonstrates that two closely related legume species can respond to Si in distinct ways, depending on plant genotype and symbiosis. These results present the overlooked function of Si in legume–rhizobia interactions, which could potentially enhance productivity of this important group of plants. A free Plain Language Summary can be found within the Supporting Information of this article.
The Leinster and Cobbold indices improve inferences about microbial diversity
Publisher: Elsevier BV
Date: 10-2014
Arbuscular mycorrhizal fungi promote silicon accumulation in plant roots, reducing the impacts of root herbivory
Publisher: Springer Science and Business Media LLC
Date: 28-07-2017
Finding fungal ecological strategies: Is recycling an option?
Publisher: Elsevier BV
Date: 08-2020
Soil microbes and community coalescence
Publisher: Elsevier BV
Date: 2016
The fate of carbon in a mature forest under carbon dioxide enrichment
Publisher: Springer Science and Business Media LLC
Date: 08-04-2020
Host plant colonisation by arbuscular mycorrhizal fungi stimulates immune function whereas high root silicon concentrations diminish growth in a soil-dwelling herbivore
Publisher: Elsevier BV
Date: 09-2017
Structural and functional neuroimaging changes associated with cognitive impairment and dementia in Parkinson's disease
Publisher: Elsevier BV
Date: 06-2021
The mycobiome of Australian tree hollows in relation to the Cryptococcus gattii and C. neoformans species complexes
Publisher: Wiley
Date: 07-08-2019
DOI: 10.1002/ECE3.5498
Phylogenetic trait conservatism and the evolution of functional trade-offs in arbuscular mycorrhizal fungi
Publisher: The Royal Society
Date: 09-09-2009
Abstract: The ersity of functional and life-history traits of organisms depends on adaptation as well as the legacy of shared ancestry. Although the evolution of traits in macro-organisms is well studied, relatively little is known about character evolution in micro-organisms. Here, we surveyed an ancient and ecologically important group of microbial plant symbionts, the arbuscular mycorrhizal (AM) fungi, and tested hypotheses about the evolution of functional and life-history traits. Variation in the extent of root and soil colonization by AM fungi is constrained to a few nodes basal to the most erse groups within the phylum, with relatively little variation associated with recent ergences. We found no evidence for a trade-off in biomass allocated to root versus soil colonization in three published glasshouse experiments rather these traits were positively correlated. Partial support was observed for correlated evolution between fungal colonization strategies and functional benefits of the symbiosis to host plants. The evolution of increased soil colonization was positively correlated with total plant biomass and shoot phosphorus content. Although the effect of AM fungi on infection by root pathogens was phylogenetically conserved, there was no evidence for correlated evolution between the extent of AM fungal root colonization and pathogen infection. Variability in colonization strategies evolved early in the ersification of AM fungi, and we propose that these strategies were influenced by functional interactions with host plants, resulting in an evolutionary stasis resembling trait conservatism.
Ecological drivers of soil microbial diversity and soil biological networks in the Southern Hemisphere
Publisher: Wiley
Date: 12-02-2018
DOI: 10.1002/ECY.2137
Abstract: The ecological drivers of soil bio ersity in the Southern Hemisphere remain underexplored. Here, in a continental survey comprising 647 sites, across 58 degrees of latitude between tropical Australia and Antarctica, we evaluated the major ecological patterns in soil bio ersity and relative abundance of ecological clusters within a co-occurrence network of soil bacteria, archaea and eukaryotes. Six major ecological clusters (modules) of co-occurring soil taxa were identified. These clusters exhibited strong shifts in their relative abundances with increasing distance from the equator. Temperature was the major environmental driver of the relative abundance of ecological clusters when Australia and Antarctica are analyzed together. Temperature, aridity, soil properties and vegetation types were the major drivers of the relative abundance of different ecological clusters within Australia. Our data supports significant reductions in the ersity of bacteria, archaea and eukaryotes in Antarctica vs. Australia linked to strong reductions in temperature. However, we only detected small latitudinal variations in soil bio ersity within Australia. Different environmental drivers regulate the ersity of soil archaea (temperature and soil carbon), bacteria (aridity, vegetation attributes and pH) and eukaryotes (vegetation type and soil carbon) across Australia. Together, our findings provide new insights into the mechanisms driving soil bio ersity in the Southern Hemisphere.
Comparative Herbivory Rates and Secondary Metabolite Profiles in the Leaves of Native and Non-Native Lonicera Species
Publisher: Springer Science and Business Media LLC
Date: 12-11-2015
DOI: 10.1007/S10886-015-0648-9
Abstract: Non-native plants introduced to new habitats can have significant ecological impact. In many cases, even though they interact with the same community of potential herbivores as their new native competitors, they regularly receive less damage. Plants produce secondary metabolites in their leaves that serve a range of defensive functions, including resistance to herbivores and pathogens. Abiotic factors such as nutrient availability can influence the expression of defensive traits, with some species exhibiting increased chemical defense in low-nutrient conditions. Plants in the genus Lonicera are known to produce a erse array of these secondary metabolites, yet non-native Lonicera species sustain lower amounts of herbivore damage than co-occurring native Lonicera species in North America. In this study, we searched for evidence of biochemical novelty in non-native species, and quantified its association with resistance to herbivores. In order to achieve this, we evaluated the phenolic and iridoid glycoside profiles in leaves of native and non-native Lonicera species grown under high and low fertilization treatments in a common garden. We then related these profiles to naturally occurring herbivore damage on whole plants in the garden. Herbivore damage was greater on native Lonicera, and chemical profiles and concentrations of selected putative defense compounds varied by species. Geographic origin was an inconsistent predictor of chemical variation in detected phenolics and iridoid glycosides (IGs). Overall, fertilization did not affect herbivore damage or measures of phenolics or IGs, but there were some fertilization effects within species. While we cannot conclude that non-natives were more chemically novel than native Lonicera species, chemical defense profiles and concentrations of specific compounds varied by species. Reduced attraction or deterrence of oviposition, specific direct resistance traits, or a combination of both may contribute to reduced herbivory and competitive advantages for non-native Lonicera in North America.
Dryland forest management alters fungal community composition and decouples assembly of root- and soil-associated fungal communities
Publisher: Elsevier BV
Date: 06-2017
Deciphering the relative contributions of multiple functions within plant–microbe symbioses
Publisher: Wiley
Date: 06-2010
DOI: 10.1890/09-1858.1
Abstract: For microbial symbioses with plants, such as mycorrhizas, we typically quantify either the net effects of one partner on another or a single function a symbiont provides. However, many microbial symbioses provide multiple functions to plants that vary based on the microbial species or functional group, plant species, and environment. Here we quantified the relative contributions of multiple functions provided by arbuscular mycorrhizal (AM) fungi to symbiont-mediated changes in plant biomass. We used two published data sets, one that measured multiple functions (pathogen protection and nutrient uptake) on a single plant and one that measured a single function (pathogen protection) on multiple plants. Using structural equation modeling, we observed strong variation in the functional pathways by which AM fungi altered plant growth changes in plant biomass were associated with different functions (and different AM fungal functional groups) for the different plant species. Utilizing this methodology across multiple partners and environments will allow researchers to gauge the relative importance of functions they isolate and, perhaps more importantly, those they did not consider. This baseline information is essential for establishing the specific mechanisms by which microbial symbioses influence plant ersity and to more effectively utilize these organisms in agriculture, restoration and conservation.
Potentials and pitfalls in the analysis of bipartite networks to understand plant–microbe interactions in changing environments
Publisher: Wiley
Date: 17-10-2018
Method or madness: does OTU delineation bias our perceptions of fungal ecology?
Publisher: Wiley
Date: 08-05-2014
DOI: 10.1111/NPH.12823
Separating the effect of crop from herbicide on soil microbial communities in glyphosate-resistant corn
Publisher: Elsevier BV
Date: 05-2009
Resource allocation to growth or luxury consumption drives mycorrhizal responses
Publisher: Wiley
Date: 08-2019
DOI: 10.1111/ELE.13353
Abstract: Highly variable phenotypic responses in mycorrhizal plants challenge our functional understanding of plant-fungal mutualisms. Using non-invasive high-throughput phenotyping, we observed that arbuscular mycorrhizal (AM) fungi relieved phosphorus (P) limitation and enhanced growth of Brachypodium distachyon under P-limited conditions, while photosynthetic limitation under low nitrogen (N) was exacerbated by the fungus. However, these responses were strongly dependent on host genotype: only the faster growing genotype (Bd3-1) utilised P transferred from the fungus to achieve improved growth under P-limited conditions. Under low N, the slower growing genotype (Bd21) had a carbon and N surplus that was linked to a less negative growth response compared with the faster growing genotype. These responses were linked to the regulation of N : P stoichiometry, couples resource allocation to growth or luxury consumption in erse plant lineages. Our results attest strongly to a mechanism in plants by which plant genotype-specific resource economics drive phenotypic outcomes during AM symbioses.
Introducing BASE: The Biomes of Australian Soil Environments soil microbial diversity database
Publisher: Oxford University Press (OUP)
Date: 28-09-2021
First report of oomycetes associated with the invasive tree Parkinsonia aculeata (Family: Fabaceae)
Publisher: Springer Science and Business Media LLC
Date: 30-05-2017
Pastures and Climate Extremes: Impacts of Cool Season Warming and Drought on the Productivity of Key Pasture Species in a Field Experiment
Publisher: Frontiers Media SA
Date: 07-03-2022
Abstract: Shifts in the timing, intensity and/or frequency of climate extremes, such as severe drought and heatwaves, can generate sustained shifts in ecosystem function with important ecological and economic impacts for rangelands and managed pastures. The Pastures and Climate Extremes experiment (PACE) in Southeast Australia was designed to investigate the impacts of a severe winter/spring drought (60% rainfall reduction) and, for a subset of species, a factorial combination of drought and elevated temperature (ambient +3°C) on pasture productivity. The experiment included nine common pasture and Australian rangeland species from three plant functional groups (C 3 grasses, C 4 grasses and legumes) planted in monoculture. Winter/spring drought resulted in productivity declines of 45% on average and up to 74% for the most affected species ( Digitaria eriantha ) during the 6-month treatment period, with eight of the nine species exhibiting significant yield reductions. Despite considerable variation in species’ sensitivity to drought, C 4 grasses were more strongly affected by this treatment than C 3 grasses or legumes. Warming also had negative effects on cool-season productivity, associated at least partially with exceedance of optimum growth temperatures in spring and indirect effects on soil water content. The combination of winter/spring drought and year-round warming resulted in the greatest yield reductions. We identified responses that were either additive ( Festuca ), or less-than-additive ( Medicago ), where warming reduced the magnitude of drought effects. Results from this study highlight the sensitivity of erse pasture species to increases in winter and spring drought severity similar to those predicted for this region, and that anticipated benefits of cool-season warming are unlikely to be realized. Overall, the substantial negative impacts on productivity suggest that future, warmer, drier climates will result in shortfalls in cool-season forage availability, with profound implications for the livestock industry and natural grazer communities.
Deterministic processes vary during community assembly for ecologically dissimilar taxa
Publisher: Springer Science and Business Media LLC
Date: 05-10-2015
DOI: 10.1038/NCOMMS9444
Abstract: The continuum hypothesis states that both deterministic and stochastic processes contribute to the assembly of ecological communities. However, the contextual dependency of these processes remains an open question that imposes strong limitations on predictions of community responses to environmental change. Here we measure community and habitat turnover across multiple vertical soil horizons at 183 sites across Scotland for bacteria and fungi, both dominant and functionally vital components of all soils but which differ substantially in their growth habit and dispersal capability. We find that habitat turnover is the primary driver of bacterial community turnover in general, although its importance decreases with increasing isolation and disturbance. Fungal communities, however, exhibit a highly stochastic assembly process, both neutral and non-neutral in nature, largely independent of disturbance. These findings suggest that increased focus on dispersal limitation and biotic interactions are necessary to manage and conserve the key ecosystem services provided by these assemblages.
Effect of glyphosate on the tripartite symbiosis formed by Glomus intraradices, Bradyrhizobium japonicum, and genetically modified soybean
Publisher: Elsevier BV
Date: 2009
Bridging reproductive and microbial ecology: a case study in arbuscular mycorrhizal fungi
Publisher: Springer Science and Business Media LLC
Date: 30-11-2018
Plant trait effects on soil organisms and functions
Publisher: Elsevier BV
Date: 11-2017
Trade-Offs between Silicon and Phenolic Defenses may Explain Enhanced Performance of Root Herbivores on Phenolic-Rich Plants.
Publisher: Springer Science and Business Media LLC
Date: 08-2016
DOI: 10.1007/S10886-016-0734-7
Abstract: Phenolic compounds play a role in plant defense against herbivores. For some herbivorous insects, particularly root herbivores, host plants with high phenolic concentrations promote insect performance and tissue consumption. This positive relationship between some insects and phenolics, however, could reflect a negative correlation with other plant defenses acting against insects. Silicon is an important element for plant growth and defense, particularly in grasses, as many grass species take up large amounts of silicon. Negative impact of a high silicon diet on insect herbivore performance has been reported aboveground, but is unreported for belowground herbivores. It has been hypothesized that some silicon accumulating plants exhibit a trade-off between carbon-based defense compounds, such as phenolics, and silicon-based defenses. Here, we investigated the impact of silicon concentrations and total phenolic concentrations in sugarcane roots on the performance of the root-feeding greyback canegrub (Dermolepida albohirtum). Canegrub performance was positively correlated with root phenolics, but negatively correlated with root silicon. We found a negative relationship in the roots between total phenolics and silicon concentrations. This suggests the positive impact of phenolic compounds on some insects may be the effect of lower concentrations of silicon compounds in plant tissue. This is the first demonstration of plant silicon negatively affecting a belowground herbivore.
Unpredictable assembly of arbuscular mycorrhizal fungal communities
Publisher: Elsevier BV
Date: 2016
Impact of forest management practices on soil bacterial diversity and consequences for soil processes
Publisher: Elsevier BV
Date: 03-2016
Compositional divergence and convergence in arbuscular mycorrhizal fungal communities
Publisher: Wiley
Date: 05-2012
DOI: 10.1890/11-1030.1
Abstract: In spite of the controversy that they have generated, neutral models provide ecologists with powerful tools for creating dynamic predictions about beta- ersity in ecological communities. Ecologists can achieve an understanding of the assembly rules operating in nature by noting when and how these predictions are met or not met. This is particularly valuable for those groups of organisms that are challenging to study under natural conditions (e.g., bacteria and fungi). Here, we focused on arbuscular mycorrhizal fungal (AMF) communities and performed an extensive literature search that allowed us to synthesize the information in 19 data sets with the minimal requisites for creating a null hypothesis in terms of community dissimilarity expected under neutral dynamics. In order to achieve this task, we calculated the first estimates of neutral parameters for several AMF communities from different ecosystems. Communities were shown either to be consistent with neutrality or to erge or converge with respect to the levels of compositional dissimilarity expected under neutrality. These data support the hypothesis that ergence occurs in systems where the effect of limited dispersal is overwhelmed by anthropogenic disturbance or extreme biological and environmental heterogeneity, whereas communities converge when systems have the potential for niche ergence within a relatively homogeneous set of environmental conditions. Regarding the study cases that were consistent with neutrality, the s ling designs employed may have covered relatively homogeneous environments in which the effects of dispersal limitation overwhelmed minor differences among AMF taxa that would lead to environmental filtering. Using neutral models we showed for the first time for a soil microbial group the conditions under which different assembly processes may determine different patterns of beta- ersity. Our synthesis is an important step showing how the application of general ecological theories to a model microbial taxon has the potential to shed light on the assembly and ecological dynamics of communities.
Relationships between mycorrhizal type and leaf flammability in the Australian flora
Publisher: Elsevier BV
Date: 11-2017
Distributional shifts in ectomycorrizhal fungal communities lag behind climate-driven tree upward migration in a conifer forest-high elevation shrubland ecotone
Publisher: Elsevier BV
Date: 10-2019
Mycorrhizal responsiveness trends in annual crop plants and their wild relatives—a meta-analysis on studies from 1981 to 2010
Publisher: Springer Science and Business Media LLC
Date: 19-01-2012
Variability of arbuscular mycorrhizal fungal communities within the root systems of individual plants is high and influenced by host species and root phosphorus
Publisher: Elsevier BV
Date: 02-2021
Good neighbors aplenty: fungal endophytes rarely exhibit competitive exclusion patterns across a span of woody habitats
Publisher: Wiley
Date: 24-07-2019
DOI: 10.1002/ECY.2790
Abstract: Environmental forces and biotic interactions, both positive and negative, structure ecological communities, but their relative roles remain obscure despite strong theory. For instance, ecologically similar species, based on the principle of limiting similarity, are expected to be most competitive and show negative interactions. Specious communities that assemble along broad environmental gradients afford the most power to test theory, but the communities often are difficult to quantify. Microbes, specifically fungal endophytes of wood, are especially suited for testing community assembly theory because they are relatively easy to s le across a comprehensive range of environmental space with clear axes of variation. Moreover, endophytes mediate key forest carbon cycle processes, and although saprophytic fungi from dead wood typically compete, endophytic fungi in living wood may enhance success through cooperative symbioses. To classify interactions within endophyte communities, we analyzed fungal DNA barcode variation across 22 woody plant species growing in woodlands near Richmond, New South Wales, Australia. We estimated the response of endophytes to the measured wood environment (i.e., 11 anatomical and chemical wood traits) and each other using latent-variable models and identified recurrent communities across wood environments using model-based classification. We used this information to evaluate whether (1) co-occurrence patterns are consistent with strong competitive exclusion, and (2) a priori classifications by trophic mode and phylum distinguish taxa that are more likely to have positive vs. negative associations under the principle of limiting similarity. Fungal endophytes were erse (mean = 140 taxa/s le), with differences in community composition structured by wood traits. Variation in wood water content and carbon concentration were associated with especially large community shifts. Surprisingly, after accounting for wood traits, fungal species were still more than three times more likely to have positive than negative co-occurrence patterns. That is, patterns consistent with strong competitive exclusion were rare, and positive interactions among fungal endophytes were more common than expected. Confirming the frequency of positive vs. negative interactions among fungal taxa requires experimental tests, and our findings establish clear paths for further study. Evidence to date intriguingly suggests that, across a wide range of wood traits, cooperation may outweigh combat for these fungi.
Evolutionary criteria outperform operational approaches in producing ecologically relevant fungal species inventories
Publisher: Wiley
Date: 24-12-2010
Species but not genotype diversity strongly impacts the establishment of rare colonisers
Publisher: Wiley
Date: 23-03-2017
Silicon accumulation suppresses arbuscular mycorrhizal fungal colonisation in the model grass Brachypodium distachyon
Publisher: Springer Science and Business Media LLC
Date: 17-05-2022
DOI: 10.1007/S11104-022-05463-9
Abstract: Silicon (Si) accumulation by grasses alleviates erse biotic and abiotic stresses. Despite this important functional role, we have limited understanding of how root microbial symbionts, such as arbuscular mycorrhizal (AM) fungi, affect Si uptake and even less about how Si supply and accumulation affect AM fungal colonisation. Our objective was to determine the nature of this two–way interaction in the model grass, Brachypodium distachyon. We grew B. distachyon with five levels of Si supplementation using wild-type plants and a mutant ( Bdlsi1-1 ) that has little capacity for Si uptake. Half of the plants were colonised by AM fungi half were free of AM fungi. We measured Si accumulation, AM fungal colonisation, leaf carbon (C), nitrogen (N) and phosphorus (P) concentrations. AM fungi did not affect Si accumulation, although small increases occurred when root mass was included as a covariate. Si supplemented soil promoted plant growth and P uptake. Si accumulation suppressed colonisation by AM fungi and C concentrations in wild type but not in Bdlsi1-1 plants. Si concentrations were negatively correlated with C and N concentrations, with correlations being stronger in wild-type plants than Bdlsi1-1 plants. Our results indicate that Si accumulation in the plant, rather than Si availability in the soil, underpinned reduced AMF colonisation. We propose that Si accumulation is unlikely to be impacted by AM fungi in plants with inherently high Si accumulation, but Si accumulation may suppress AM fungal colonisation in such plants.
Temporal dynamics in biotic and functional recovery following mining
Publisher: Wiley
Date: 19-04-2022
Abstract: Human‐induced disturbance has substantially influenced the structure and function of terrestrial ecosystems globally. However, the extent to which multiple ecosystem functions (multifunctionality) recover following anthropogenic disturbance (ecosystem recovery) remains poorly understood. We report on the first study examining the temporal dynamics in recovery of multifunctionality from 3 to 12 years after the commencement of rehabilitation following mining‐induced disturbance, and relate this information to changes in biota. We examined changes in 57 biotic (plants, microbial) and functional (soil) attributes associated with bio ersity and ecosystem services at four open‐cut coal mines in eastern Australia. Increasing time since commencement of rehabilitation was associated with increases in overall multifunctionality, soil microbial abundance, plant productivity, plant structure and soil stability, but not nutrient cycling, soil carbon sequestration nor soil nutrients. However, the temporal responses of in idual ecosystem properties varied widely, from strongly positive (e.g. litter cover, fine and coarse frass, seed biomass, microbial and fungal biomass) to strongly negative (groundstorey foliage cover). We also show that sites with more developed biota tended to have greater ecosystem multifunctionality. Moreover, recovery of plant litter was closely associated with recovery of most microbial components, soil integrity and soil respiration. Overall, however, rehabilitated sites still differed from reference ecosystems a decade after commencement of rehabilitation. Synthesis and applications . The dominant role of plant and soil biota and litter cover in relation to functions associated with soil respiration, microbial function, soil integrity and C and N pools suggests that recovering bio ersity is a critically important priority in rehabilitation programs. Nonetheless, the slow recovery of most functions after a decade indicates that rehabilitation after open‐cut mining is likely to protracted.
Nitrogen niche partitioning between tropical legumes and grasses strengthens under elevated CO2
Publisher: Cold Spring Harbor Laboratory
Date: 19-01-2023
DOI: 10.1101/2023.01.16.524162
Abstract: Plant community bio ersity can be maintained, at least partially, by shifts in species interactions between facilitation and competition for resources as environmental conditions change. These interactions also drive ecosystem functioning, including productivity, and can promote over-yielding-an ecosystem service prioritized in working landscapes that occurs when there is either less competition, more facilitation, or both, between species in a community than within species. Importantly, shifts in species interactions that can result in over-yielding are unclear given rising CO 2 concentrations, especially in the context of tropical mixed-species grasslands. We examined the relative performance of two species pairs of tropical pasture grasses and legumes growing in monoculture and mixtures in a glasshouse experiment manipulating CO 2 . We investigated how over-yielding can arise from nitrogen (N) niche partitioning and biotic facilitation using stable isotopes to differentiate soil N from biological N fixation (BNF) within N acquisition into aboveground biomass for these two-species mixtures. We found that N niche partitioning in species-level use of soil N vs. BNF drove species interactions in mixtures. Importantly partitioning, though not necessarily overyielding, was generally enhanced under elevated CO 2 . However, this finding was mixture-dependent based on biomass of dominant species in mixtures and the strength of selection effects for the dominant mixture species. This study demonstrates that rising atmospheric CO 2 may alter niche partitioning between co-occurring species, with negative implications for the over-yielding benefits predicted for legume-grass mixtures in working landscapes with tropical species. Furthermore, these changes in inter-species interactions have consequences for shifts in grassland composition that are not yet considered in larger-scale projections for impacts of climate change and species distributions. Among our tropical pasture species we found that grasses (dotted lines) grown in monoculture rely fully on soil nitrogen (N), while legumes (solid lines) grown in monoculture relied approximately equally on soil N and biological nitrogen fixation (BNF) to meet N requirements. When grown with tropical grasses, however, legumes shifted to rely more strongly on BNF, indicative of niche partitioning and decreased competition for soil nutrients with grasses. This separation of niche space was strengthened under elevated CO 2 conditions, ultimately reducing legume production.
Fungal genome size and composition reflect ecological strategies along soil fertility gradients
Publisher: Wiley
Date: 20-04-2023
DOI: 10.1111/ELE.14224
Abstract: Genomic traits reflect the evolutionary processes that have led to ecological variation among extant organisms, including variation in how they acquire and use resources. Soil fungi have erse nutritional strategies and exhibit extensive variation in fitness along resource gradients. We tested for trade‐offs in genomic traits with mycelial nutritional traits and hypothesize that such trade‐offs differ among fungal guilds as they reflect contrasting resource exploitation and habitat preferences. We found species with large genomes exhibited nutrient‐poor mycelium and low GC content. These patterns were observed across fungal guilds but with varying explanatory power. We then matched trait data to fungal species observed in 463 Australian grassland, woodland and forest soil s les. Fungi with large genomes and lower GC content dominated in nutrient‐poor soils, associated with shifts in guild composition and with species turnover within guilds. These findings highlight fundamental mechanisms that underpin successful ecological strategies for soil fungi.
Resolution of respect for Ekkehard von Törne (1925–2017)
Publisher: Elsevier BV
Date: 09-2017
Priorities for research in soil ecology
Publisher: Elsevier BV
Date: 07-2017
DOI: 10.1016/J.PEDOBI.2017.05.003
Abstract: The ecological interactions that occur in and with soil are of consequence in many ecosystems on the planet. These interactions provide numerous essential ecosystem services, and the sustainable management of soils has attracted increasing scientific and public attention. Although soil ecology emerged as an independent field of research many decades ago, and we have gained important insights into the functioning of soils, there still are fundamental aspects that need to be better understood to ensure that the ecosystem services that soils provide are not lost and that soils can be used in a sustainable way. In this perspectives paper, we highlight some of the major knowledge gaps that should be prioritized in soil ecological research. These research priorities were compiled based on an online survey of 32 editors of Pedobiologia - Journal of Soil Ecology. These editors work at universities and research centers in Europe, North America, Asia, and Australia.The questions were categorized into four themes: (1) soil bio ersity and biogeography, (2) interactions and the functioning of ecosystems, (3) global change and soil management, and (4) new directions. The respondents identified priorities that may be achievable in the near future, as well as several that are currently achievable but remain open. While some of the identified barriers to progress were technological in nature, many respondents cited a need for substantial leadership and goodwill among members of the soil ecology research community, including the need for multi-institutional partnerships, and had substantial concerns regarding the loss of taxonomic expertise.
Branching out: Towards a trait-based understanding of fungal ecology
Publisher: Elsevier BV
Date: 05-2015
Benefits of silicon-enhanced root nodulation in a model legume are contingent upon rhizobial efficacy
Publisher: Springer Science and Business Media LLC
Date: 11-03-2022
DOI: 10.1007/S11104-022-05358-9
Abstract: Silicon (Si) uptake and accumulation improves plant resilience to environmental stresses, but most studies examining this functional role of Si have focussed on grasses (Poaceae) and neglected other important plant groups, such as legumes (Fabaceae). Legumes have evolved a symbiotic relationship with nitrogen-fixing bacteria (rhizobia) housed in root nodules. Our study determined the impacts of silicon (Si) supplementation on Medicago truncatula inoculated with Ensifer meliloti rhizobial strains that differed in their capacity for nitrogen fixation: Sm1021 (‘low-efficiency’) or Sm1022 (‘high-efficiency’). We examined how Si and rhizobial efficacy influence nodule and plant functional traits, including their chemical aspects. These combinations were supplied with or without Si in a glasshouse experiment, where we quantified nodule flavonoids and foliar chemistry (free amino acids, soluble protein, elemental C, N and Si). Si supply increased nodule number per plant, specific nodule flavonoid concentrations, contents of foliar nitrogenous compounds and foliar C, but not foliar Si. We also demonstrated that rhizobial efficacy altered the magnitude of Si effects on certain traits. For ex le, Si significantly promoted concentrations of foliar N and soluble protein in the plants associated with the ‘low-efficiency’ strain only, and this was not the case with the ‘high-efficiency’ one. Collectively, our study indicates that Si generates positive effects on M. truncatula , particularly when the association with rhizobia is relatively inefficient, and may play a more prominent role in rhizobial functionality than previously thought.
Reciprocal Effects of Silicon Supply and Endophytes on Silicon Accumulation and Epichloë Colonization in Grasses
Publisher: Frontiers Media SA
Date: 27-10-2020
Plant pathogen protection by arbuscular mycorrhizas: A role for fungal diversity?
Publisher: Elsevier BV
Date: 05-2010
Plant–microbe interactions: novel applications for exploitation in multipurpose remediation technologies
Publisher: Elsevier BV
Date: 08-2012
DOI: 10.1016/J.TIBTECH.2012.04.004
Abstract: Soil remediation that revitalizes degraded or contaminated land while simultaneously contributing to biomass biofuel production and carbon sequestration is an attractive strategy to meet the food and energy requirements of the burgeoning world population. As a result, plant-based remediation approaches have been gaining in popularity. The drawbacks of phytoremediation, particularly those associated with low productivity and limitations to the use of contaminant-containing biomass, could be addressed through novel biotechnological approaches that harness recent advances in our understanding of chemical interactions between plants and microorganisms in the rhizosphere and within plant tissues. This opinion article highlights three promising approaches that provide environmental and economic benefits of bioremediation: transgenics, low-input 'designer' plants and nanotechnology.
Abrupt rise in atmospheric CO2 overestimates community response in a model plant–soil system
Publisher: Springer Science and Business Media LLC
Date: 02-2005
DOI: 10.1038/NATURE03268
Abstract: Attempts to understand the ecological effect of increasing atmospheric CO2 concentration, [CO2], usually involve exposing today's ecosystems to expected future [CO2] levels. However, a major assumption of these approaches has not been tested--that exposing ecosystems to a single-step increase in [CO2] will yield similar responses to those of a gradual increase over several decades. We tested this assumption on a mycorrhizal fungal community over a period of six years. [CO2] was either increased abruptly, as is typical of most [CO2] experiments, or more gradually over 21 generations. The two approaches resulted in different structural and functional community responses to increased [CO2]. Some fungi were sensitive to the carbon pulse of the abrupt [CO2] treatment. This resulted in an immediate decline in fungal species richness and a significant change in mycorrhizal functioning. The magnitude of changes in fungal ersity and functioning in response to gradually increasing [CO2] was smaller, and not significantly different to those with ambient [CO2]. Our results suggest that studies may overestimate some community responses to increasing [CO2] because biota may be sensitive to ecosystem changes that occur as a result of abrupt increases.
Effects of genetically modified, herbicide‐tolerant crops and their management on soil food web properties and crop litter decomposition
Publisher: Wiley
Date: 03-03-2009
Real-Time Polymerase Chain Reaction Monitoring of Recombinant DNA Entry into Soil from Decomposing Roundup Ready Leaf Biomass
Publisher: American Chemical Society (ACS)
Date: 21-06-2008
DOI: 10.1021/JF800767G
Abstract: Glyphosate-tolerant, Roundup Ready (RR) soybeans account for about 57% of all genetically modified (GM) crops grown worldwide. The entry of recombinant DNA into soil from GM crops has been identified as an environmental concern due to the possibility of their horizontal transfer to soil microorganisms. RR soybeans contain recombinant gene sequences that can be differentiated from wild-type plant and microbial genes in soil by using a sequence-specific molecular beacon and real-time polymerase chain reaction (PCR). A molecular beacon-based real-time PCR system to quantify a wild-type soybean lectin ( le1) gene was designed to compare amounts of endogenous soybean genes to recombinant DNA in soil. Microcosm studies were carried out to develop methodologies for the detection of recombinant DNA from RR soybeans in soil. RR soybean leaf litterbags were imbedded in the soil under controlled environmental conditions (60% water holding capacity, 10/15 degrees C, and 8/16 h day/night) for 30 days. The soybean biomass decomposition was described using a single-phase exponential equation, and the DNA concentration in planta and in soil was quantified using real-time PCR using sequence-specific molecular beacons for the recombinant cp4 epsps and endogenous soybean lectin ( le1) genes. The biomass of RR soybean leaves was 8.6% less than nontransgenic (NT) soybean leaves after 30 days. The pooled half-disappearance time for cp4 epsps and le1 in RR and of le1 in NT soybean leaves was 1.4 days. All genes from leaves were detected in soil after 30 days. This study provides a methodology for monitoring the entry of RR and NT soybean DNA into soil from decomposing plant residues.
The effect of environmental and phylogenetic drivers on community assembly in an alpine meadow community
Publisher: Wiley
Date: 11-2012
DOI: 10.1890/11-2212.1
Abstract: To predict the consequences of environmental change on plant communities at local scales, one needs to understand the regional drivers structuring these communities. Here, we used a formal analytical framework incorporating functional traits and evolutionary histories to understand the importance of environmental filtering and species interactions in the assembly of alpine plant communities. The study was conducted in the Tibetan Plateau using field plots experiencing changes in land use (fertilization and grazing). We observed evidence for both trait-based convergence (associated with plant height and tissue nitrogen) and ergence (associated with specific leaf area) within alpine plant communities, suggesting that environmental filtering and limiting similarity are acting simultaneously during assembly processes. Although we did not observe evidence of phylogenetic niche conservatism in relation to intensified land use, we did observe support for the phylogenetic structure of plant communities influencing community-weighted mean trait values, suggesting that evolutionary constraints represent a significant driver of community assembly in this system. Therefore, evolutionary and ecological processes may have independent effects on alpine plant communities facing land use intensification.
Factors Affecting the Presence and Persistence of Plant DNA in the Soil Environment in Corn and Soybean Rotations
Publisher: Cambridge University Press (CUP)
Date: 10-2008
DOI: 10.1614/WS-08-044.1
Abstract: This study investigated factors that influence occurrence and persistence of plant DNA in the soil environment in three crop rotations. In each rotation, soil was s led in May before planting, in July and August while crops were growing, and in October after harvest. Total DNA was recovered from soil s les taken at two different depths in the soil profile and quantified. Three target plant genes (corn CP4 epsps , corn 10-kD Zein , and soybean CP4 epsps ) also were quantified in these DNA extracts using species-specific quantitative real-time PCR assays. In general, total plant DNA content in the soil environment was greatest when the crop was growing in the field and decreased rapidly after harvest. Nevertheless, low levels of target plant DNA were often still detectable the following spring. Age of rotation did not influence target DNA quantities found in the soil environment. Data were collected for a combination of 10 location-years, which allowed for estimation of the variance components for six factors including time of s ling, year, location, crop, s ling depth, and herbicide to total and target DNA content in the soil s les. Mean target recombinant DNA content in soil was influenced most strongly by time of s ling and year (85 and 6%, respectively), whereas total soil DNA content was less dynamic and was most strongly influenced by location and year (49 and 25%, respectively). Over the duration of this study, no accumulation of transgenic plant DNA in the soil environment was observed.
Termite sensitivity to temperature affects global wood decay rates
Publisher: American Association for the Advancement of Science (AAAS)
Date: 28-09-2022
Abstract: Deadwood is a large global carbon store with its store size partially determined by biotic decay. Microbial wood decay rates are known to respond to changing temperature and precipitation. Termites are also important decomposers in the tropics but are less well studied. An understanding of their climate sensitivities is needed to estimate climate change effects on wood carbon pools. Using data from 133 sites spanning six continents, we found that termite wood discovery and consumption were highly sensitive to temperature (with decay increasing .8 times per 10°C increase in temperature)—even more so than microbes. Termite decay effects were greatest in tropical seasonal forests, tropical savannas, and subtropical deserts. With tropicalization (i.e., warming shifts to tropical climates), termite wood decay will likely increase as termites access more of Earth’s surface.
Conservation by translocation: establishment of Wollemi pine and associated microbial communities in novel environments
Publisher: Springer Science and Business Media LLC
Date: 20-08-2016
Detection of transgenic cp4 epsps genes in the soil food web
Publisher: Springer Science and Business Media LLC
Date: 12-2009
DOI: 10.1051/AGRO/2009020
Mycorrhizal and Rhizobial Colonization of Genetically Modified and Conventional Soybeans
Publisher: American Society for Microbiology
Date: 07-2007
DOI: 10.1128/AEM.00594-07
Abstract: We grew plants of nine soybean varieties, six of which were genetically modified to express transgenic cp4-epsps , in the presence of Bradyrhizobium japonicum and arbuscular mycorrhizal fungi. Mycorrhizal colonization and nodule abundance and mass differed among soybean varieties however, in no case was variation significantly associated with the genetic modification.
Accounting for uncertainty in species delineation during the analysis of environmental DNA sequence data
Publisher: Wiley
Date: 31-05-2011
From patterns to causal understanding: Structural equation modeling (SEM) in soil ecology
Publisher: Elsevier BV
Date: 03-2015
Ecological understanding of root-infecting fungi using trait-based approaches
Publisher: Elsevier BV
Date: 07-2014
DOI: 10.1016/J.TPLANTS.2014.02.006
Abstract: Classification schemes have been popular to tame the ersity of root-infecting fungi. However, the usefulness of these schemes is limited to descriptive purposes. We propose that a shift to a multidimensional trait-based approach to disentangle the saprotrophic-symbiotic continuum will provide a better framework to understand fungal evolutionary ecology. Trait information reflecting the separation of root-infecting fungi from free-living soil relatives will help to understand the evolutionary process of symbiosis, the role that species interactions play in maintaining their large ersity in soil and in planta, and their contributions at the ecosystem level. Methodological advances in several areas such as microscopy, plant immunology, and metatranscriptomics represent emerging opportunities to populate trait databases.
Phosphorus availability and arbuscular mycorrhizal fungi limit soil C cycling and influence plant responses to elevated CO2 conditions
Publisher: Cold Spring Harbor Laboratory
Date: 18-07-2021
DOI: 10.1101/2021.07.16.452715
Abstract: Enhanced soil organic matter (SOM) decomposition and organic phosphorus (P) cycling may help sustain plant productivity under elevated CO 2 (eCO 2 ) and P-limiting conditions. P-acquisition by arbuscular mycorrhizal (AM) fungi and their impacts on SOM decomposition may become even more relevant in these conditions. Yet, experimental evidence of the interactive effect of AM fungi and P availability influencing altered SOM cycling under eCO 2 is scarce and the mechanisms of this control are poorly understood. Here, we performed a pot experiment manipulating P availability, AM fungal presence and atmospheric CO 2 levels and assessed their impacts on soil C cycling and plant growth. Plants were grown in chambers with a continuous 13 C-input that allowed differentiation between plant- and SOM-derived fractions of respired CO 2 (R), dissolved organic C (DOC) and microbial biomass (MBC) as relevant C pools in the soil C cycle. We hypothesised that under low P availability, increases in SOM cycling may support sustained plant growth under eCO 2 and that AM fungi would intensify this effect. We found the impacts of CO 2 enrichment and P availability on soil C cycling were generally independent of each other with higher root biomass and slight increases in soil C cycling under eCO 2 occurring regardless of the P treatment. Contrary to our hypotheses, soil C cycling was enhanced with P addition suggesting that low P conditions were limiting soil C cycling. eCO 2 conditions increased the fraction of SOM-derived DOC pointing to increased SOM decomposition with eCO 2 . Finally, AM fungi increased microbial biomass under eCO 2 conditions and low-P without enhanced soil C cycling, probably due to competitive interactions with free-living microorganisms over nutrients. Our findings in this plant-soil system suggest that, contrary to what has been reported for N-limited systems, the impacts of eCO 2 and P availability on soil C cycling are independent of each other.
An empirical approach to target DNA quantification in environmental samples using real-time polymerase chain reactions
Publisher: Elsevier BV
Date: 08-2007
Fire severity and the post‐fire soil environment affect seedling regeneration success of the threatened Persoonia hirsuta (Proteaceae)
Publisher: Wiley
Date: 25-06-2022
DOI: 10.1111/AEC.13217
Abstract: Climate change and land management decisions have considerably altered fire regimes globally resulting in increased risks of extreme fire seasons. Fire intensity is one characteristic of fire regime which is projected to increase. However, the magnitude and impact of intense fires on plant habitat and life history characteristics (such as the soil environment or seedling recruitment) remain unclear for many species. The widespread 2019–2020 Black Summer fires across Eastern Australia provided the opportunity to examine the impact of these fires on the short‐term regeneration of the Endangered Persoonia hirsuta (Proteaceae), an obligate seeding (reliant on regeneration from seed following fire) shrub presently threatened by population decline and dieback (plant death from branch and root tips backwards) of an unknown cause. In this study, we used a combination of metrics to estimate fire severity in the field at 22 plots across three fire‐affected populations which we used as a proxy to understand the relative impacts of fire intensity on P. hirsuta regeneration post‐fire. We also recorded the recruitment, growth, dieback and mortality of P. hirsuta seedlings at these plots over 21 months following the fires and examined whether the post‐fire soil environment (carbon, nitrogen and phosphorus) was related to fire severity and seedling responses. Seedling recruitment and growth were variable across sites and showed no relationship to fire severity. However, seedling dieback and mortality were significantly higher among plots exposed to high severity fires. Additionally, characteristics of the post‐fire soil environment varied by fire severity and explained variation in seedling recruitment, growth and dieback. Our work provides important evidence that already vulnerable populations of P. hirsuta may be further threatened by increasing fire severity, highlighting the importance of understanding the effects of fire on habitat and life history characteristics for threatened plants.
Compositional Divergence and Convergence in Local Communities and Spatially Structured Landscapes
Publisher: Public Library of Science (PLoS)
Date: 26-04-2012
A new tool of the trade: plant-trait based approaches in microbial ecology
Publisher: Springer Science and Business Media LLC
Date: 23-01-2013
Soil microbial communities influence seedling growth of a rare conifer independent of plant–soil feedback
Publisher: Wiley
Date: 12-2016
DOI: 10.1002/ECY.1594
Abstract: Plant-soil feedback, the reciprocal relationship between a plant and its associated microbial communities, has been proposed to be an important driver of plant populations and community dynamics. While rarely considered, understanding how plant-soil feedback contributes to plant rarity may have implications for conservation and management of rare species. Wollemi pine (Wollemia nobilis) is a critically endangered species, of which fewer than 100 trees are known to exist in the wild. Seedling survival within the first year after germination and subsequent recruitment of Wollemi pine is limited in the wild. We used a plant-soil feedback approach to investigate the functional effect of species-specific differences previously observed in the microbial communities underneath adult Wollemi pine and a neighboring species, coachwood (Ceratopetalum apetalum), and also whether additional variation in microbial communities in the wild could impact seedling growth. There was no evidence for seedling growth being affected by tree species associated with soil inocula, suggesting that plant-soil feedbacks are not limiting recruitment in the natural population. However, there was evidence of fungal, but not bacterial, community variation impacting seedling growth independently of plant-soil feedbacks. Chemical (pH) and physical (porosity) soil characteristics were identified as potential drivers of the functional outcomes of these fungal communities. The empirical approach described here may provide opportunities to identify the importance of soil microbes to conservation efforts targeting other rare plant species and is also relevant to understanding the importance of soil microbes and plant-soil feedbacks for plant community dynamics more broadly.
Environmental and Geographical Factors Structure Soil Microbial Diversity in New Caledonian Ultramafic Substrates: A Metagenomic Approach
Publisher: Public Library of Science (PLoS)
Date: 12-2016
Biodiversity of arbuscular mycorrhizal fungi and ecosystem function
Publisher: Wiley
Date: 30-03-2018
DOI: 10.1111/NPH.15119
Abstract: Contents Summary 1059 I. Introduction: pathways of influence and pervasiveness of effects 1060 II. AM fungal richness effects on ecosystem functions 1062 III. Other dimensions of bio ersity 1062 IV. Back to basics - primary axes of niche differentiation by AM fungi 1066 V. Functional ersity of AM fungi - a role for biological stoichiometry? 1067 VI. Past, novel and future ecosystems 1068 VII. Opportunities and the way forward 1071 Acknowledgements 1072 References 1072 SUMMARY: Arbuscular mycorrhizal (AM) fungi play important functional roles in ecosystems, including the uptake and transfer of nutrients, modification of the physical soil environment and alteration of plant interactions with other biota. Several studies have demonstrated the potential for variation in AM fungal ersity to also affect ecosystem functioning, mainly via effects on primary productivity. Diversity in these studies is usually characterized in terms of the number of species, unique evolutionary lineages or complementary mycorrhizal traits, as well as the ability of plants to discriminate among AM fungi in space and time. However, the emergent outcomes of these relationships are usually indirect, and thus context dependent, and difficult to predict with certainty. Here, we advocate a fungal-centric view of AM fungal bio ersity-ecosystem function relationships that focuses on the direct and specific links between AM fungal fitness and consequences for their roles in ecosystems, especially highlighting functional ersity in hyphal resource economics. We conclude by arguing that an understanding of AM fungal functional ersity is fundamental to determine whether AM fungi have a role in the exploitation of marginal/novel environments (whether past, present or future) and highlight avenues for future research.
Advances in understanding arbuscular mycorrhizal fungal effects on soil nutrient cycling
Publisher: Burleigh Dodds Science Publishing
Date: 19-01-2021
Abstract: Arbuscular mycorrhizal (AM) fungi assist with plant acquisition of nutrients, with most studies focussing on the nutrient forms taken up and translocated to the host. Recent studies have focussed on how extraradical fungal hyphae can affect nutrient ransformations, leaching and movement. However, it is still unclear the extent that nutrient cycling is influenced in agricultural contexts. Moreover, much of the mechanistic knowledge is limited to a few plants and fungi studied under controlled conditions, suggesting a need for innovation addressing the broader ersity of agricultural AM plant-fungal associations. This chapter summarises how AM fungi can influence specific soil nutrient processes, then focuses specifically on AM fungi in crop production systems and ex les of (in)compatibilities in these systems. These research areas are then contextualized with new approaches to understand AM fungal roles in nutrient acquisition and utilisation, which the authors propose will lead to applications in improving nutrient use efficiency of agroecosystems.
Climate warming negates arbuscular mycorrhizal fungal reductions in soil phosphorus leaching with tall fescue but not lucerne
Publisher: Elsevier BV
Date: 2021
Fine endophytes (Glomus tenue) are related to Mucoromycotina, not Glomeromycota
Publisher: Wiley
Date: 21-10-2016
DOI: 10.1111/NPH.14268
Fungal functional ecology: bringing a trait‐based approach to plant‐associated fungi
Publisher: Wiley
Date: 25-11-2019
DOI: 10.1111/BRV.12570
Abstract: Fungi play many essential roles in ecosystems. They facilitate plant access to nutrients and water, serve as decay agents that cycle carbon and nutrients through the soil, water and atmosphere, and are major regulators of macro-organismal populations. Although technological advances are improving the detection and identification of fungi, there still exist key gaps in our ecological knowledge of this kingdom, especially related to function. Trait-based approaches have been instrumental in strengthening our understanding of plant functional ecology and, as such, provide excellent models for deepening our understanding of fungal functional ecology in ways that complement insights gained from traditional and -omics-based techniques. In this review, we synthesize current knowledge of fungal functional ecology, taxonomy and systematics and introduce a novel database of fungal functional traits (Fun
Interchange of entire communities: microbial community coalescence
Publisher: Elsevier BV
Date: 08-2015
DOI: 10.1016/J.TREE.2015.06.004
Abstract: Microbial communities are enigmatically erse. We propose a novel view of processes likely affecting microbial assemblages, which could be viewed as the Great American Interchange en miniature: the wholesale exchange among microbial communities resulting from moving pieces of the environment containing entire assemblages. Incidental evidence for such 'community coalescence' is accumulating, but such processes are rarely studied, likely because of the absence of suitable terminology or a conceptual framework. We provide the nucleus for such a conceptual foundation for the study of community coalescence, examining factors shaping these events, links to bodies of ecological theory, and we suggest modeling approaches for understanding coalescent communities. We argue for the systematic study of community coalescence because of important functional and applied consequences.
Aboveground resource allocation in response to root herbivory as affected by the arbuscular mycorrhizal symbiosis
Publisher: Springer Science and Business Media LLC
Date: 18-12-2019
The influence of roots on mycorrhizal fungi, saprotrophic microbes and carbon dynamics in a low‐phosphorus Eucalyptus forest under elevated CO2
Publisher: Wiley
Date: 03-06-2021
Abstract: Elevated atmospheric carbon dioxide (eCO 2 ) can impact soil organic matter (SOM) dynamics by changing the rates of carbon (C) losses and gains. In the rhizosphere, these changes are usually assumed to be the result of root‐mediated eCO 2 impacts on saprotrophic microbes via altered below‐ground C allocation. This C allocation can also impact mycorrhizal fungi and their role in SOM dynamics. However, direct field quantifications of the influence of roots on both mycorrhizal fungi and saprotrophs together with SOM dynamics in forests exposed to eCO 2 are rare. This is especially true in phosphorus (P)‐limited systems, even though ecosystem responses to eCO 2 are known to depend on P availability. We assessed root mediation of eCO 2 impacts on saprotrophs, mycorrhizal fungi, and C dynamics of root litter and mineral soil C (SOM‐C) in a mature, P‐limited Eucalyptus woodland exposed to eCO 2 . We used a novel nested‐mesh‐bag method to manipulate roots access to the substrates in a 1‐year field incubation. We used an isotopic approach to trace C dynamics and performed a comprehensive microbial community analysis, along with nutrients and enzymatic activity measurements. Roots increased microbial biomass, fungal:bacterial ratio, plant‐derived C gains and substrate C losses while decreasing P availability and specific enzymatic activity. eCO 2 increased bacterial relative abundance in root litter and protozoa in SOM‐C, but it did not enhance root impacts or mycorrhizal fungi biomass. Our combination of in‐situ approaches allowed us to demonstrate that while roots have multiple impacts on soil microbial communities and C dynamics, they are not the main drivers of responses to eCO 2 in this P‐limited forest. Other factors beyond enhanced root‐derived below‐ground C inputs such as seasonality of nutrient and water availability, and shifts in plant communities may be more important in modulating eCO 2 impacts on soil dynamics in P‐limited systems. A free Plain Language Summary can be found within the Supporting Information of this article.
Assessing translocation management techniques through experimental trials: a case study of the endangered shrub Persoonia hirsuta
Publisher: Wiley
Date: 23-11-2022
DOI: 10.1111/REC.13603
Abstract: Translocation is commonly used in the conservation of threatened species to help mitigate the risk of local extinctions. However, translocations are often limited by knowledge of the species ecological requirements that promote persistence in the landscape. Small translocation trials with a strong experimental design can help to address species knowledge gaps and identify effective strategies for the successful establishment of a threatened species prior to implementing full‐scale planting regimes. In this study, we experimentally translocated 128 plants of the endangered Persoonia hirsuta (Proteaceae) at a dry sclerophyll mining offset in New South Wales (NSW), Australia, and investigated the effects of propagation type (seeds and vegetative cuttings), plant guards, and mulching on short‐term plant growth and survival. Transplants were impacted by herbivory and unprecedented extreme temperatures over summer 2019–2020 with 25 of the 128 plants surviving after 20 months of monitoring. Among the surviving in iduals, all but one were seed propagated and 72% of survivors were protected by a plant guard. Short‐term survival and establishment of P. hirsuta translocants was increased by producing plants from seeds, and the use of plant guards with localized mulch. We also identified significantly greater root volume, projected area, and diameter for seedlings than cuttings grown plants. Our study successfully identified several key factors that should be considered for the ongoing management of P. hirsuta and vindicates the importance of small experimental trials when planning threatened plant translocations.
Linking Soil Organisms Within Food Webs to Ecosystem Functioning and Environmental Change
Publisher: Elsevier
Date: 2007
An insect ecosystem engineer alleviates drought stress in plants without increasing plant susceptibility to an above‐ground herbivore
Publisher: Wiley
Date: 19-11-2015
AusTraits, a curated plant trait database for the Australian flora
Publisher: Springer Science and Business Media LLC
Date: 30-09-2021
DOI: 10.1038/S41597-021-01006-6
Abstract: We introduce the AusTraits database - a compilation of values of plant traits for taxa in the Australian flora (hereafter AusTraits). AusTraits synthesises data on 448 traits across 28,640 taxa from field c aigns, published literature, taxonomic monographs, and in idual taxon descriptions. Traits vary in scope from physiological measures of performance (e.g. photosynthetic gas exchange, water-use efficiency) to morphological attributes (e.g. leaf area, seed mass, plant height) which link to aspects of ecological variation. AusTraits contains curated and harmonised in idual- and species-level measurements coupled to, where available, contextual information on site properties and experimental conditions. This article provides information on version 3.0.2 of AusTraits which contains data for 997,808 trait-by-taxon combinations. We envision AusTraits as an ongoing collaborative initiative for easily archiving and sharing trait data, which also provides a template for other national or regional initiatives globally to fill persistent gaps in trait knowledge.
Mycorrhizal fungi enhance nutrient uptake but disarm defences in plant roots, promoting plant-parasitic nematode populations
Publisher: Elsevier BV
Date: 11-2018
Root type is not an important driver of mycorrhizal colonisation in Brachypodium distachyon
Publisher: Elsevier BV
Date: 11-2017
Recent trends and future strategies in soil ecological research—Integrative approaches at Pedobiologia
Publisher: Elsevier BV
Date: 2014
Impacts of elevated carbon dioxide on carbon gains and losses from soil and associated microbes in a Eucalyptus woodland
Publisher: Elsevier BV
Date: 04-2020
Invasive Plant Suppresses the Growth of Native Tree Seedlings by Disrupting Belowground Mutualisms
Publisher: Public Library of Science (PLoS)
Date: 25-04-2006
Circular linkages between soil biodiversity, fertility and plant productivity are limited to topsoil at the continental scale
Publisher: Wiley
Date: 13-06-2017
DOI: 10.1111/NPH.14634
Abstract: The current theoretical framework suggests that tripartite positive feedback relationships between soil bio ersity, fertility and plant productivity are universal. However, empirical evidence for these relationships at the continental scale and across different soil depths is lacking. We investigate the continental‐scale relationships between the ersity of microbial and invertebrate‐based soil food webs, fertility and above‐ground plant productivity at 289 sites and two soil depths, that is 0–10 and 20–30 cm, across Australia. Soil bio ersity, fertility and plant productivity are strongly positively related in surface soils. Conversely, in the deeper soil layer, the relationships between soil bio ersity, fertility and plant productivity weaken considerably, probably as a result of a reduction in bio ersity and fertility with depth. Further modeling suggested that strong positive associations among soil bio ersity–fertility and fertility–plant productivity are limited to the upper soil layer (0–10 cm), after accounting for key factors, such as distance from the equator, altitude, climate and physicochemical soil properties. These findings highlight the importance of surface soil bio ersity for soil fertility, and suggest that any loss of surface soil could potentially break the links between soil bio ersity–fertility and/or fertility–plant productivity, which can negatively impact nutrient cycling and food production, upon which future generations depend.
Cycling of extracellular DNA in the soil environment
Publisher: Elsevier BV
Date: 12-2007
β‐diversity in temperate grasslands is driven by stronger environmental filtering of plant species with large genomes
Publisher: Wiley
Date: 17-01-2023
DOI: 10.1002/ECY.3941
Abstract: Elucidating mechanisms underlying community assembly and bio ersity patterns is central to ecology and evolution. Genome size (GS) has long been hypothesized to potentially affect species' capacity to tolerate environmental stress and might therefore help drive community assembly. However, its role in driving β‐ ersity (i.e., spatial variability in species composition) remains unclear. We measured GS for 161 plant species and community composition across 52 sites spanning a 3200‐km transect in the temperate grasslands of China. By correlating the turnover of species composition with environmental dissimilarity, we found that resource filtering (i.e., environmental dissimilarity that includes precipitation, and soil nitrogen and phosphorus concentrations) affected β‐ ersity patterns of large‐GS species more than small‐GS species. By contrast, geographical distance explained more variation of β‐ ersity for small‐GS than for large‐GS species. In a 10‐year experiment manipulating levels of water, nitrogen, and phosphorus, adding resources increased plant biomass in species with large GS, suggesting that large‐GS species are more sensitive to the changes in resource availability. These findings highlight the role of GS in driving community assembly and predicting species responses to global change.
Erratum: Introducing BASE: The Biomes of Australian Soil Environments soil microbial diversity database [GigaScience. 5, 1, (2016) (1-11)] DOI: 10.1186/s13742-016-0126-5
Publisher: Oxford University Press (OUP)
Date: 05-2017
Tree diversity modifies distance‐dependent effects on seedling emergence but not plant–soil feedbacks of temperate trees
Publisher: Wiley
Date: 06-2015
DOI: 10.1890/14-1166.1
Variation in soil microbial communities associated with critically endangered Wollemi pine affects fungal, but not bacterial, assembly within seedling roots
Publisher: Elsevier BV
Date: 2016
Quantification and Persistence of Recombinant DNA of Roundup Ready Corn and Soybean in Rotation
Publisher: American Chemical Society (ACS)
Date: 13-11-2007
DOI: 10.1021/JF072457Z
Abstract: The presence of the recombinant cp4 epsps gene from Roundup Ready (RR) corn and RR soybean was quantified using real-time PCR in soil s les from a field experiment growing RR and conventional corn and soybean in rotation. RR corn and RR soybean cp4 epsps persisted in soil for up to 1 year after seeding. The concentration of recombinant DNA in soil peaked in July and August in RR corn and RR soybean plots, respectively. A small fraction of soil s les from plots seeded with conventional crops contained recombinant DNA, suggesting transgene dispersal by means of natural process or agricultural practices. This research will aid in the understanding of the persistence of recombinant DNA in agricultural cropping systems.
Environmental cues for dispersal in a filamentous fungus in simulated islands
Publisher: Wiley
Date: 09-04-2020
DOI: 10.1111/OIK.07000
Biogeography of arbuscular mycorrhizal fungal spore traits along an aridity gradient, and responses to experimental rainfall manipulation
Publisher: Elsevier BV
Date: 08-2020
Does threatened species listing status predict climate change risk? A case study with Australian Persoonia (Proteaceae) species
Publisher: Elsevier BV
Date: 11-2021
Arbuscular mycorrhizal fungal-mediated reductions in N2O emissions were not impacted by experimental warming for two common pasture species
Publisher: Elsevier BV
Date: 08-2021
Related Organisations
Leibniz Institute For Media Research | Hans Bredow Institute
Location: Germany
Related Funding Activities
Discovery Projects - Grant ID: DP160103765
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End Date: 12-2021
Amount: $324,700.00
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View Funded ActivityDiscovery Projects - Grant ID: DP130102501
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View Funded ActivityARC Future Fellowships - Grant ID: FT190100590
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View Funded ActivityDiscovery Projects - Grant ID: DP140103936
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View Funded ActivityIndustrial Transformation Research Hubs - Grant ID: IH210100001
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