scholarly journals Anthropogenic Disturbance Impacts Mycorrhizal Communities and Abiotic Soil Properties: Implications for an Endemic Forest Disease

2021 ◽  
Vol 3 ◽  
Author(s):  
Sarah J. Sapsford ◽  
Trudy Paap ◽  
Giles E. St. J. Hardy ◽  
Treena I. Burgess
Keyword(s):  
Soil Properties ◽  
Soil Nutrients ◽  
Large Scale ◽  
Stand Structure ◽  
Disease Incidence ◽  
Arbuscular Mycorrhizal ◽  
Am Fungi ◽  
Illumina Miseq ◽  
Fungal Communities ◽  
Canker Disease

In forest ecosystems, habitat fragmentation negatively impacts stand structure and biodiversity; the resulting fragmented patches of forest have distinct, disturbed edge habitats that experience different environmental conditions than the interiors of the fragments. In southwest Western Australia, there is a large-scale decline of the keystone tree species Corymbia calophylla following fragmentation and land use change. These changes have altered stand structure and increased their susceptibility to an endemic fungal pathogen, Quambalaria coyrecup, which causes chronic canker disease especially along disturbed forest habitats. However, the impacts of fragmentation on belowground processes in this system are not well-understood. We examined the effects of fragmentation on abiotic soil properties and ectomycorrhizal (ECM) and arbuscular mycorrhizal (AM) fungal communities, and whether these belowground changes were drivers of disease incidence. We collected soil from 17 sites across the distribution range of C. calophylla. Soils were collected across a gradient from disturbed, diseased areas to undisturbed, disease-free areas. We analysed soil nutrients and grew C. calophylla plants as a bioassay host. Plants were harvested and roots collected after 6 months of growth. DNA was extracted from the roots, amplified using fungal specific primers and sequenced using Illumina MiSeq. Concentrations of key soil nutrients such as nitrogen, phosphorus and potassium were much higher along the disturbed, diseased edges in comparison to undisturbed areas. Disturbance altered the community composition of ECM and AM fungi; however, only ECM fungal communities had lower rarefied richness and diversity along the disturbed, diseased areas compared to undisturbed areas. Accounting for effects of disturbance, ECM fungal diversity and leaf litter depth were highly correlated with increased disease incidence in C. calophylla. In the face of global change, increased virulence of an endemic pathogen has emerged in this Mediterranean-type forest.

scholarly journals Extraction of short chain chitooligosaccharides from fungal biomass and their use as promoters of arbuscular mycorrhizal symbiosis

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Andrea Crosino ◽  
Elisa Moscato ◽  
Marco Blangetti ◽  
Gennaro Carotenuto ◽  
Federica Spina ◽  
...  
Keyword(s):  
Fungal Biomass ◽  
Large Scale ◽  
Low Cost ◽  
Trichoderma Viride ◽  
Arbuscular Mycorrhizal ◽  
Am Fungi ◽  
Production Costs ◽  
Short Chain ◽  
Mycorrhizal Symbiosis ◽  
Major Interest

AbstractShort chain chitooligosaccharides (COs) are chitin derivative molecules involved in plant-fungus signaling during arbuscular mycorrhizal (AM) interactions. In host plants, COs activate a symbiotic signalling pathway that regulates AM-related gene expression. Furthermore, exogenous CO application was shown to promote AM establishment, with a major interest for agricultural applications of AM fungi as biofertilizers. Currently, the main source of commercial COs is from the shrimp processing industry, but purification costs and environmental concerns limit the convenience of this approach. In an attempt to find a low cost and low impact alternative, this work aimed to isolate, characterize and test the bioactivity of COs from selected strains of phylogenetically distant filamentous fungi: Pleurotus ostreatus, Cunninghamella bertholletiae and Trichoderma viride. Our optimized protocol successfully isolated short chain COs from lyophilized fungal biomass. Fungal COs were more acetylated and displayed a higher biological activity compared to shrimp-derived COs, a feature that—alongside low production costs—opens promising perspectives for the large scale use of COs in agriculture.

scholarly journals Arbuscular Mycorrhizal Fungal Communities in the Soils of Desert Habitats

2021 ◽  
Vol 9 (2) ◽  
pp. 229
Author(s):  
Martti Vasar ◽  
John Davison ◽  
Siim-Kaarel Sepp ◽  
Maarja Öpik ◽  
Mari Moora ◽  
...  
Keyword(s):  
Plant Root ◽  
Significant Proportion ◽  
Arbuscular Mycorrhizal ◽  
Am Fungi ◽  
Illumina Miseq ◽  
Desert Ecosystems ◽  
Fungal Dna ◽  
Root Symbionts ◽  
Arbuscular Mycorrhizal Fungal

Deserts cover a significant proportion of the Earth’s surface and continue to expand as a consequence of climate change. Mutualistic arbuscular mycorrhizal (AM) fungi are functionally important plant root symbionts, and may be particularly important in drought stressed systems such as deserts. Here we provide a first molecular characterization of the AM fungi occurring in several desert ecosystems worldwide. We sequenced AM fungal DNA from soil samples collected from deserts in six different regions of the globe using the primer pair WANDA-AML2 with Illumina MiSeq. We recorded altogether 50 AM fungal phylotypes. Glomeraceae was the most common family, while Claroideoglomeraceae, Diversisporaceae and Acaulosporaceae were represented with lower frequency and abundance. The most diverse site, with 35 virtual taxa (VT), was in the Israeli Negev desert. Sites representing harsh conditions yielded relatively few reads and low richness estimates, for example, a Saudi Arabian desert site where only three Diversispora VT were recorded. The AM fungal taxa recorded in the desert soils are mostly geographically and ecologically widespread. However, in four sites out of six, communities comprised more desert-affiliated taxa (according to the MaarjAM database) than expected at random. AM fungal VT present in samples were phylogenetically clustered compared with the global taxon pool, suggesting that nonrandom assembly processes, notably habitat filtering, may have shaped desert fungal assemblages.

scholarly journals Long-term Effects of Mixed Planting on Arbuscular Mycorrhizal Fungal Communities in the Roots and Soils of Juglans mandshurica Plantations

2020 ◽  
Author(s):  
Li Ji ◽  
Yan Zhang ◽  
Yuchun Yang ◽  
Lixue Yang ◽  
Na Yang ◽  
...  
Keyword(s):  
Fungal Community ◽  
Arbuscular Mycorrhizal ◽  
Am Fungi ◽  
Soil Samples ◽  
Fungal Communities ◽  
Juglans Mandshurica ◽  
Mixed Plantations ◽  
Mixed Plantation ◽  
Unique Otus

Abstract Background: Establishing mixed plantations is an effective way to improve soil fertility and increase forest productivity. Arbuscular mycorrhizal (AM) fungi are obligate symbiotic fungi that can promote mineral nutrient absorption and regulate intraspecific and interspecific competition in plants. However, the effects of mixed plantations on the community structure and abundance of AM fungi are still unclear. Illumina MiSeq sequencing was used to investigate the AM fungal community in the roots and soils of pure and mixed plantations (Juglans mandshurica × Larix gmelinii). The objective of this study is to compare the differential responses of the root and rhizosphere soil AM fungal communities of Juglans mandshurica to long-term mixed plantation management.Results: Glomus and Paraglomus were the dominant genera in the root samples, accounting for more than 80% of the sequences. Compared with that in the pure plantation, the relative abundance of Glomus was higher in the mixed plantation. Glomus, Diversispora and Paraglomus accounted for more than 85% of the sequences in the soil samples. The relative abundances of Diversispora and an unidentified genus of Glomeromycetes were higher and lower in the pure plantation, respectively. The Root_P samples (the roots in the pure plantation) had the highest number of unique OTUs (operational taxonomic units), which belonged mainly to an unidentified genus of Glomeromycetes, Paraglomus, Glomus and Acaulospora. The number of unique OTUs detected in the soil was lower than that in the roots. In both the root and soil samples, the forest type did not have a significant effect on AM fungal diversity, but the Sobs value and the Shannon, Chao1 and Ace indices of AM fungi in the roots were significantly higher than those in the soil.Conclusions: Mixed forest management had little effect on the AM fungal community of Juglans mandshurica roots and significantly changed the community composition of the soil AM fungi, but not the diversity.

Arbuscular mycorrhizal fungal succession in a long-lived perennial

Botany ◽  
2014 ◽  
Vol 92 (4) ◽  
pp. 313-320 ◽  
Author(s):  
Miranda M. Hart ◽  
Monika Gorzelak ◽  
Diane Ragone ◽  
Susan J. Murch
Keyword(s):  
High Throughput Sequencing ◽  
Selective Pressure ◽  
Arbuscular Mycorrhizal ◽  
Am Fungi ◽  
Fungal Communities ◽  
Artocarpus Altilis ◽  
Host Identity ◽  
Arbuscular Mycorrhizal Fungal ◽  
Insight Into

It is difficult to understand why arbuscular mycorrhizal (AM) fungal communities change over time. The role of host identity confounds our understanding of successional changes in AM fungal communities because hosts exert strong selective pressure on their root-associated microbes. In this study we looked at the AM fungi associated with a long-lived perennial breadfruit (Artocarpus altilis (Parkinson) Fosberg) to see how AM communities change over the life span of a single, long-lived host. Using 454 high-throughput sequencing, we found evidence that older trees had more AM fungal taxa than younger trees and were associated with different AM fungal communities, but these differences were not apparent early in the life cycle. Older trees were dominated by species of Rhizophagus, whereas younger trees and genets were dominated by species of Glomus. Some taxa were only detected in older trees (e.g., Funneliformis) or genets (e.g., Racocetra and Scutellospora), indicating that certain AM fungal taxa may serve as “indicators” of the successional age of the fungal community. These results provide important information about a poorly studied system and give insight into how AM communities change over longer time scales.

scholarly journals Illumina-based identification of arbuscular mycorrhizal fungi from Karachay-Cherkessia soils for development of bio-fertilizers

2021 ◽  
Vol 285 ◽  
pp. 03001
Author(s):  
Andrey Yurkov ◽  
Alexey Kryukov ◽  
Yulia Mikhaylova ◽  
Peter Zhurbenko
Keyword(s):  
Mycorrhizal Fungi ◽  
Biological Diversity ◽  
Arbuscular Mycorrhizal ◽  
Its Region ◽  
Am Fungi ◽  
Illumina Miseq ◽  
Universal Primers ◽  
Its2 Region ◽  
North Caucasus ◽  
The Future

The aim of the study was to investigate the species diversity of AM fungi in different parts of the North Caucasus, biodiversity hotspot, the center of the world’s biological diversity. Samples were taken from 5 locations (stationary trial plots, STPs) in different ecosystems and at various altitudes. Identification was performed using sequencing for ITS1 and ITS2 regions, amplified with universal primers, Illumina MiSeq was employed. 19 genera of AM fungi were found on all STPs. The work did not reveal a correlation between the altitude and the species composition of AM fungi. At the same time, it should be assumed that a correlation could be found between the biodiversity of AM fungi and the type of ecosystem, which should be done in the future. The study shows it is necessary to use an analysis for both ITS regions, since the data obtained for each ITS region differ and complement each other. Analysis for the ITS2 region revealed 1.3 times more virtual taxa than for the ITS1, while the number of OTUs identified per species was similar for both regions. The highest biodiversity of AM fungi was found in STP #3 (with meadow flora). Only 4 species (Rhizophagus irregularis, R. intraradices, Paraglomus laccatum, and Claroideoglomus claroideum) were found on all five analyzed STPs. We found unexpectedly that with such a high biodiversity among the identified fungi, no different species were found in the Paraglomus genus, all the sequences of Paraglomus belonged to Paraglomus laccatum, whereas at least 9 species are distinguished in the genus by morphology. Further research will allow us to identify new strains of AM fungi, the efficiency of which may be higher than already studied ones. In the future this will make it possible to create more effective microbial biofertilizers for agriculture.

scholarly journals Long-term effects of mixed planting on arbuscular mycorrhizal fungal communities in the roots and soils of Juglans mandshurica plantations

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Li Ji ◽  
Yan Zhang ◽  
Yuchun Yang ◽  
Lixue Yang ◽  
Na Yang ◽  
...  
Keyword(s):  
Fungal Community ◽  
Arbuscular Mycorrhizal ◽  
Am Fungi ◽  
Soil Samples ◽  
Fungal Communities ◽  
Juglans Mandshurica ◽  
Mixed Plantations ◽  
Mixed Plantation ◽  
Unique Otus

Abstract Background Establishing mixed plantations is an effective way to improve soil fertility and increase forest productivity. Arbuscular mycorrhizal (AM) fungi are obligate symbiotic fungi that can promote mineral nutrient absorption and regulate intraspecific and interspecific competition in plants. However, the effects of mixed plantations on the community structure and abundance of AM fungi are still unclear. Illumina MiSeq sequencing was used to investigate the AM fungal community in the roots and soils of pure and mixed plantations (Juglans mandshurica × Larix gmelinii). The objective of this study is to compare the differential responses of the root and rhizosphere soil AM fungal communities of Juglans mandshurica to long-term mixed plantation management. Results Glomus and Paraglomus were the dominant genera in the root samples, accounting for more than 80% of the sequences. Compared with that in the pure plantation, the relative abundance of Glomus was higher in the mixed plantation. Glomus, Diversispora and Paraglomus accounted for more than 85% of the sequences in the soil samples. The relative abundances of Diversispora and an unidentified genus of Glomeromycetes were higher and lower in the pure plantation, respectively. The Root_P samples (the roots in the pure plantation) had the highest number of unique OTUs (operational taxonomic units), which belonged mainly to an unidentified genus of Glomeromycetes, Paraglomus, Glomus and Acaulospora. The number of unique OTUs detected in the soil was lower than that in the roots. In both the root and soil samples, the forest type did not have a significant effect on AM fungal diversity, but the Sobs value and the Shannon, Chao1 and Ace indices of AM fungi in the roots were significantly higher than those in the soil. Conclusions Mixed forest management had little effect on the AM fungal community of Juglans mandshurica roots and significantly changed the community composition of the soil AM fungi, but not the diversity.

scholarly journals Resource limitation is a driver of local adaptation in mycorrhizal symbioses

2010 ◽  
Vol 107 (5) ◽  
pp. 2093-2098 ◽  
Author(s):  
Nancy Collins Johnson ◽  
Gail W. T. Wilson ◽  
Matthew A. Bowker ◽  
Jacqueline A. Wilson ◽  
R. Michael Miller
Keyword(s):  
Local Adaptation ◽  
Resource Limitation ◽  
Arbuscular Mycorrhizal ◽  
Am Fungi ◽  
Andropogon Gerardii ◽  
Fungal Communities ◽  
Geographic Structure ◽  
Mycorrhizal Associations ◽  
Local Soil ◽  
Key Driver

Symbioses may be important mechanisms of plant adaptation to their environment. We conducted a reciprocal inoculation experiment to test the hypothesis that soil fertility is a key driver of local adaptation in arbuscular mycorrhizal (AM) symbioses. Ecotypes ofAndropogon gerardiifrom phosphorus-limited and nitrogen-limited grasslands were grown with all possible “home and away” combinations of soils and AM fungal communities. Our results indicate thatAndropogonecotypes adapt to their local soil and indigenous AM fungal communities such that mycorrhizal exchange of the most limiting resource is maximized. Grasses grown in home soil and inoculated with home AM fungi produced more arbuscules (symbiotic exchange structures) in their roots than those grown in away combinations. Also, regardless of the host ecotype, AM fungi produced more extraradical hyphae in their home soil, and locally adapted AM fungi were, therefore, able to sequester more carbon compared with nonlocal fungi. Locally adapted mycorrhizal associations were more mutualistic in the two phosphorus-limited sites and less parasitic at the nitrogen-limited site compared with novel combinations of plants, fungi, and soils. To our knowledge, these findings provide the strongest evidence to date that resource availability generates evolved geographic structure in symbioses among plants and soil organisms. Thus, edaphic origin of AM fungi should be considered when managing for their benefits in agriculture, ecosystem restoration, and soil-carbon sequestration.

scholarly journals Building de novo reference genome assemblies of complex eukaryotic microorganisms from single nuclei

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Merce Montoliu-Nerin ◽  
Marisol Sánchez-García ◽  
Claudia Bergin ◽  
Manfred Grabherr ◽  
Barbara Ellis ◽  
...  
Keyword(s):  
Large Scale ◽  
Method Development ◽  
De Novo ◽  
Sequence Data ◽  
Arbuscular Mycorrhizal ◽  
Am Fungi ◽  
Life Cycles ◽  
Suitable Model ◽  
Eukaryotic Microorganisms ◽  
Genome Assemblies

AbstractThe advent of novel sequencing techniques has unraveled a tremendous diversity on Earth. Genomic data allow us to understand ecology and function of organisms that we would not otherwise know existed. However, major methodological challenges remain, in particular for multicellular organisms with large genomes. Arbuscular mycorrhizal (AM) fungi are important plant symbionts with cryptic and complex multicellular life cycles, thus representing a suitable model system for method development. Here, we report a novel method for large scale, unbiased nuclear sorting, sequencing, and de novo assembling of AM fungal genomes. After comparative analyses of three assembly workflows we discuss how sequence data from single nuclei can best be used for different downstream analyses such as phylogenomics and comparative genomics of single nuclei. Based on analysis of completeness, we conclude that comprehensive de novo genome assemblies can be produced from six to seven nuclei. The method is highly applicable for a broad range of taxa, and will greatly improve our ability to study multicellular eukaryotes with complex life cycles.

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