Download or read book Diversity and Function of Root associated Fungal Communities in Relation to Nitrogen Nutrition in Temperate Forests written by Quang Dung Nguyen and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Ectomycorrhizal fungi form symbiotic association with roots of a variety of plant species. They provide plants with nutrients in exchange of photosynthetic carbohydrates. In natural ecosystems, plants form associations not only with ectomycorrhizal fungi but also with a variety of other microbes. Interest in root-associated fungal communities is increasing because they may play an important role in plant nutrition and fitness. Nitrogen (N) is an essential nutrient for plant growth and development but often a limiting factor in forest ecosystems. To date, little is known on the relationship ...

Download or read book Root associated Fungal Communities Critical Linkages between Plants and Soil written by Rodica Pena and published by Cuvillier Verlag. This book was released on 2024-02-07 with total page 111 pages. Available in PDF, EPUB and Kindle. Book excerpt: This research highlights the vital but often overlooked role of soil fungi in forest ecosystems, focusing on their impact on nutrient cycles, carbon storage, and plant growth. It delves into how these fungi, especially those connected to plant roots, contribute to the overall health and productivity of forests. The study breaks new ground by examining how changes in the environment, influenced by factors like climate change and forest management practices, affect these fungi and the essential services they provide. The investigation is structured into three main parts: exploring the diversity and makeup of root-associated fungal communities, using advanced infrared spectroscopy to uncover new fungal traits, and studying fungi’s roles in carbon cycling and plant nutrition. Utilizing cutting-edge molecular techniques and large ecological databases, the researchers uncover the complex interactions between fungi, their environment, and plant hosts, demonstrating how these relationships are crucial for ecosystem resilience and productivity. Key findings reveal that the diversity and structure of fungal communities are crucial for maintaining forest health, particularly in the face of environmental stressors. The study advocates for forest management strategies that promote fungal diversity to enhance ecosystem services, highlighting the importance of fungi in sustaining forest ecosystems and their potential in mitigating the impacts of climate change. This work sets the stage for future research into the intricate relationships between fungi, forests, and global ecological cycles, emphasizing the need for a deeper understanding of these critical but underappreciated organisms.

Download or read book Root associated Fungal Diversity Nutrient Mineralization and Micro climatic Interconnections written by Korena Mafune and published by . This book was released on 2021 with total page 183 pages. Available in PDF, EPUB and Kindle. Book excerpt: The temperate rainforests of western Washington are commonly recognized for their extensive areas of old-growth forest and more recently their unique canopy soil environment. Over the last 40 years, fundamental studies on canopy soils have emphasized their importance as structural and functional components of these ecosystems; but there remain many unknowns on the biotic and abiotic processes in canopy soil environments, how these may be impacted by climate change, and the implications this may have on host tree resiliency. For example, old-growth bigleaf maple trees (Acer macrophyllum Pursh.) grow extensive adventitious roots that form fungal associations. However, no studies have explored the diversity of these adventitious canopy root associated fungal communities and how they compare to forest floor rooting networks. Further, no studies have explored the seasonal mineralization rates of plant available nutrients in canopy soils and how they enhance forest-level nutrient cycling. Therefore, this study aimed to not only compare these biotic and abiotic processes between the two soil environments, but it also aimed to shed light on how these processes may be impacted by increased and decreased rainfall amounts to better understand how these trees may be affected by climate change. Prior to identifying fungal communities associating with roots in canopy and forest floor soil environments, a methodological approach for long-read sequencing of fungi was designed and tested on the MinION Nanopore Sequencer. To assess the capabilities of the MinION, three fungal mock communities were sequenced. Each had varying ratios of 16 taxa. The MinION recovered all mock community members, when mixed at equal ratios. Highly accurate consensus sequences were derived and identified to species level, proving that the MinION was suitable as a practical alternative to gain insights on root-associated fungal communities. After benchmarking this technology, roots were collected from canopy and forest floor environments to determine if there were any differences in the percent of fungal colonization. There was no significant difference between the percent of fungi colonizing adventitious canopy roots (56.5% ± 5.4) and forest floor roots (65.1% ± 3.6). Subsequently, a rainfall experiment was implemented and root associated fungal communities were identified seasonally (excluding winter) over the duration of one year. At ambient conditions, root associated fungal community composition was significantly different between the two old-growth sites and also between canopy and forest floor environments. However, these communities did not shift in response to seasonal changes. In canopy soil environments, the increased and decreased rainfall experiments and site differences also significantly affected fungal community composition; seasonality also had an effect. The MinION was able to identify a diversity of obligate mutualists and facultative endophytes. There were several species associating with adventitious canopy roots that have never been reported to associate with bigleaf maple prior to this study. Nitrogen (N) and phosphorus (P) mineralization rates were also determined seasonally during the rainfall experiment as well as annual N and P pools. In canopy soil environments, both the rainfall treatments and seasonality had a significant effect on N mineralization rates. Phosphorus mineralization rates were also impacted by the rainfall treatments. On a per mass basis at ambient conditions, canopy soils have higher rates of net N (355.3 ± 54.7 mg N kg-1 yr-1) and net P mineralization (387.6 ± 34.5 mg PO4-P kg-1 yr-1) than forest floor soils (58.2 ± 3.9 mg N kg-1 yr-1 and 387.6 ± 34.5 mg PO4-P kg-1 yr-1). When converted to an areal basis, canopy soils enhanced the annual NO3-N, NH4-N, and PO4-P mineralization pools by 5.2%, 48.4%, and 3.7%, respectively. Additionally, some of these resources are leaching to the forest floor soil environment. The first part of this study benchmarked a methodological approach that was utilized throughout the project and allowed the inference of genus and species-level resolution in canopy and forest floor environments. The other two parts of this study demonstrated that canopy soils provide an extra compartment for nutrients and that adventitious rooting systems are associating with a diversity of fungi distinct from forest floor environments. Further, higher and lower inputs of rainfall impact these biotic interactions, as well as the nutrient dynamics. Collectively, this research reveals that fungal communities associating with adventitious roots may be acting as adaptive facilitators to environmental extremes (e.g., climatic changes) and that biogeochemical cycles in canopy soils and their inputs to the ecosystem should not be overlooked.

Download or read book Assembly of Root associated Fungi in Different Soil Layers and Nitrogen Uptake by Ectomycorrhizae in Temperate Forests written by Anis Mahmud Khokon and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Fungi are a remarkably highly diverse group of organisms on Earth, playing a pivotal role in ecosystem functioning. Belowground, they act as decomposers, pathogens or symbionts. Members of these functional categories are colonizing roots and have been defined as root-associated fungi. The abundance and distribution patterns of fungal communities are determined by various environmental factors, including soil and root properties, vegetation and climatic conditions. Soil fungal communities are known to be vertically stratified across different soil layers but our knowledge about root-associat...

Download or read book Microorganisms in Soils Roles in Genesis and Functions written by Francois Buscot and published by Springer Science & Business Media. This book was released on 2007-01-04 with total page 426 pages. Available in PDF, EPUB and Kindle. Book excerpt: For this third volume of the series Soil Biology, internationally renowned scientists shed light on the significant roles of microbes in soil. Key topics covered include: bioerosion, humification, mineralization and soil aggregation; Interactions in the mycorrhizosphere; microbes and plant nutrient cycling; Microbes in soil surface or toxic metal polluted soils; Use of marker genes and isotopes in soil microbiology, and many more.

Download or read book Roles of Woody Root associated Fungi in Forest Ecosystem Processes written by Jill A. Hoff and published by . This book was released on 2004 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: Interactions between fungi and woody roots may be critical factors that influence diverse forest ecosystems processes, such as wood decay (nutrient recycling); root diseases and their biological control; and endophytic, epiphytic, and mycorrhizal symbioses. However, few studies have characterized the diversity and the spatial and temporal distribution of woody root-associated fungi in forest ecosystems. Molecular genetic techniques that facilitate fungal identification are now available to help investigate complex and dynamic interactions of these fungi.

Download or read book Fungi of Forests written by Donald Jay Nelsen and published by . This book was released on 2017 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt: Global importance of forests is difficult to overestimate, given their role in oxygen production, ecological roles in nutrient cycling and supporting numerous living species, and economic value for industry and as recreational zones. Fitness of the forest-forming trees strongly depends on microbial communities associated with tree roots. In particular, fungi impact tree fitness: mycorrhizal species provide water and nutrients for the trees in exchange for C, endophytic fungi play key roles in host defense against pathogenic organisms, and saprotrophic fungi decompose dead organic matter and facilitate nutrient cycling. In addition, pathogenic fungal species strongly affect forest fitness. Despite their importance, fungal communities associated with forest trees are largely unknown because the typical morphological assay takes into consideration a scarce portion of fungal diversity: species that produce visible fruiting bodies at relatively frequent intervals. A more accurate assessment of fungal diversity in forests has become possible with the development of next-generation sequencing, where fungal species are being identified based on the presence of their DNA in the sample. In this work, DNA-metabarcoding was utilized to assess the diversity of fungi associated with roots of forest-forming trees within the families Fagaceae and Betulaceae (Europe), and Fagaceae, and Juglandaceae (North America). The data obtained provided unprecedented insight into hidden richness of root-associated fungi, which approached 1756 OTUs (a proxy for species) in the European dataset, and 2769 - in the North American dataset. Variation in fungal community composition was largely explained by geographical location (ca. 30%). However, the effect of host specificity (ca. 9-15% of variation) was significant as well. DNA-based data revealed strong positive and negative patters in fungal co-occurrence (e.g., a positive relationship was observed between Cenococcum geophilum and species of Russulaceae), which could indicate interactions between fungal species. In addition to diversity assays, fungal responses to acid precipitation were quantified, and revealed strong declines in fungal richness and abundance, including ectomycorrhizal species. I conclude that compositional shifts in root-associated fungal communities could be particularly suitable for monitoring of forest ecosystems, given an optimal response time in fungi (not too slow as in wooded plants and not as high as in bacteria).

Download or read book Comparing Arbuscular and Ectomycorrhizal Fungal Communities in Seven North American Forests and Their Response to Nitrogen Fertilization written by Jennifer Lyn Lansing and published by . This book was released on 2003 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mycorrhizal fungi are found extensively in forest soils and play a crucial role in carbon and nitrogen cycling between plant and soil. However, little is known about how mycorrhizal communities differ between forest systems or what role they play in below ground carbon dynamics. This study addresses the basic ecological questions of how ECM and AM vary between gymnosperm and angiosperm host taxa in undisturbed forest ecosystems which vary in climate and soil characteristics. I use a manipulative N fertilization experiment to study the mycorrhizae between forest sites and their role in ecosystem cycling. AM and ECM percent colonized root length and colonized root length per minirhizotron frame differed between sites and between years. The extramatrical hyphae of all four major AM genera were present at all sites whereas spores, in low abundance, were mainly Glomus spp. Richness of ECM morphotypes was similar between sites at a variety of scales. Functional groups based on ECM morphological characters differed between sites and some fertilization effects were found. Site location was the most influential factor in determining mycorrhizal abundance, composition, and overall role in carbon and nitrogen cycling. At the P. edulis site, I intensively studied the abundance, diversity, composition, and spatial distribution of ECM using morphotyping and RFLP analysis. Years differed in ECM abundance and composition. ECM types differed in frequency across the landscape, abundance at any individual tree, and spatial aggregation. Each P. edulis tree was similar in ECM tip abundance, richness, and number of dominant ECM types. At all scales a few ECM types were dominant however there was temporal and tree to tree variability in which ECM were dominant. The individual tree is the most important sampling unit when assessing P. edulis ECM diversity and composition. Also at the P. edulis site, using RFLP analysis to identify ECM types and 14C to estimate age I found a differential response in the 14C signature of RFLP types to N fertilization indicating that N fertilization does not affect all ECM fungi similarly and functional differences in ECM fungi exist.

Download or read book Mycorrhizal Symbiosis written by Sally E. Smith and published by Academic Press. This book was released on 2010-07-26 with total page 815 pages. Available in PDF, EPUB and Kindle. Book excerpt: The roots of most plants are colonized by symbiotic fungi to form mycorrhiza, which play a critical role in the capture of nutrients from the soil and therefore in plant nutrition. Mycorrhizal Symbiosis is recognized as the definitive work in this area. Since the last edition was published there have been major advances in the field, particularly in the area of molecular biology, and the new edition has been fully revised and updated to incorporate these exciting new developments. - Over 50% new material - Includes expanded color plate section - Covers all aspects of mycorrhiza - Presents new taxonomy - Discusses the impact of proteomics and genomics on research in this area

Download or read book Nutrient Availability Does Not Affect Community Assembly in Root associated Fungi But Determines Fungal Effects on Plant Growth written by Jose G. Maciá-Vicente and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nonmycorrhizal root-colonizing fungi are key determinants of plant growth, driving processes ranging from pathogenesis to stress alleviation. Evidence suggests that they might also facilitate host access to soil nutrients in a mycorrhiza-like manner, but the extent of their direct contribution to plant nutrition is unknown. To study how widespread such capacity is across root-colonizing fungi, we surveyed soils in nutrient-limiting habitats using plant baits to look for fungal community changes in response to nutrient conditions. We established a fungal culture collection and used Arabidopsis thaliana inoculation bioassays to assess the ability of fungi to facilitate host's growth in the presence of organic nutrients unavailable to plants. Plant baits captured a representation of fungal communities extant in natural habitats and showed that nutrient limitation has little influence on community assembly. Arabidopsis thaliana inoculated with 31 phylogenetically diverse fungi exhibited a consistent fungus-driven growth promotion when supplied with organic nutrients compared to untreated plants. However, direct phosphorus measurement and RNA-seq data did not support enhanced nutrient uptake but rather that growth effects may result from changes in the plant's immune response to colonization. The widespread and consistent host responses to fungal colonization suggest that distinct, locally adapted nonmycorrhizal fungi affect plant performance across habitats. IMPORTANCE: Recent studies have shown that root-associated fungi that do not engage in classical mycorrhizal associations can facilitate the hosts' access to nutrients in a mycorrhiza-like manner. However, the generality of this capacity remains to be tested. Root-associated fungi are frequently deemed major determinants of plant diversity and performance, but in the vast majority of cases their ecological roles in nature remain unknown. Assessing how these plant symbionts affect plant productivity, diversity, and fitness is important to understanding how plant communities function. Recent years have seen important advances in the understanding of the main drivers of the diversity and structure of plant microbiomes, but a major challenge is still linking community properties with function. This study contributes to the understanding of the cryptic function of root-associated fungi by testing their ability to participate in a specific process: nutrient acquisition by plants.

Download or read book Importance of Root Symbiomes for Plant Nutrition New Insights Perspectives and Future Challenges written by Kevin Garcia and published by Frontiers Media SA. This book was released on 2020-07-01 with total page 171 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Ectomycorrhizal Fungi written by John W.G. Cairney and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 377 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mycorrhiza - the symbiosis between plants and fungi - plays a key role in plant life. This book reviews for the first time the current knowledge of 15 individual genera of ectomycorrhizal fungi. It is unique in that each chapter is dedicated to a single fungal genus, each written by internationally recognized experts on the respective fungal genera. It is thus an invaluable reference source for researchers, students and practitioners in the fields of mycorrhizal biology, mycology, forestry, plant sciences and soil biology.

Download or read book Plant fungal interactions written by Dong-Qin Dai and published by Frontiers Media SA. This book was released on 2023-08-16 with total page 409 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Water and Carbon Dynamics Ecosystem Stability of Forest and Grassland in Response to Climate Change written by Xiaoming Kang and published by Frontiers Media SA. This book was released on 2024-04-15 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: Forest and grassland ecosystems are the most important carbon sinks in terrestrial ecosystems. They can maintain or enhance carbon stocks and sinks in biomass, and play vital roles in mitigating climate change. China is taking action to achieve its carbon peak and carbon-neutral targets. Climate change, particularly the increase in the frequency, severity, and extent of drought, will affect the stability of the forest and grassland. How forests and grassland mitigate and adapt to climate change is still a challenge. Exploring the response of the forest and grassland to extreme climate events contributes to improving vegetation quality and enhancing the ability to respond to climate change.

Download or read book Drivers of Fungal Community Composition and Function in Temperate Forests written by Matthew David Gacura and published by . This book was released on 2018 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: Saprotrophic fungal communities are highly complex ecological units responsible for a wide range of terrestrial ecosystem functions, most notably the decomposition/recycling of large amounts of senesced plant tissue. These communities may be assembled by several distinct community assembly mechanisms that could be categorized into two broad groups: deterministic processes based around environmental selection, and more stochastic mechanisms arising from dispersal limitation and colonization history. However, there is much conjecture about which mechanism plays the most critical role in the formation of these ecological units. Furthermore, the spatial scale of inquiry may also influence the relative importance of these mechanisms in determining community composition. This dissertation was focused on determining the relative importance of multiple community assembly mechanisms on community composition of saprotrophic fungal communities at both large and small scales. In addition, the importance of these mechanisms in the distribution of community aggregated functional traits was also investigated.We were able to analyze the impact of numerous community assembly mechanisms. An observational approach based on a detailed sampling scheme of senesced leaves allowed for investigating the importance of how spatial scale impacts the relative importance of community assembly mechanisms. The importance of community assembly history, also known as priority effects, was analyzed using a manipulative experimental approach that involved the modification of the starting communities of saprotrophic fungi and its impact on later colonization. Community composition was analyzed using both terminal restriction fragment length polymorphism (TRFLP) and next generation sequencing technology (pyrosequencing). Community aggregated functional traits were analyzed through the identification of fungal functional groups of OTUs, analysis of GH28 pectinase genes, and the quantification of extracellular enzyme activity. In this dissertation I showed that fungal communities found on senesced leaf litter are highly diverse and made up of species from many distinct functional groups. Regarding community composition, I showed that the relative importance of distinct community assembly mechanisms depends upon both the spatial scale that is analyzed and on the resource type availability. Overall environmental factors were most important in determining community composition, although spatial proximity was found to be very important at small scales. I showed that the importance of community assembly mechanisms changes depending upon the microbial functional group being investigated. Finally, I was able to show that functional traits can be plastic in nature depending upon community history and that saprotrophic fungal communities display functional redundancy at the ecosystem scale.

Download or read book Mycorrhizal Mediation of Soil written by Nancy Collins Johnson and published by Elsevier. This book was released on 2016-11-03 with total page 526 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mycorrhizal Mediation of Soil: Fertility, Structure, and Carbon Storage offers a better understanding of mycorrhizal mediation that will help inform earth system models and subsequently improve the accuracy of global carbon model predictions. Mycorrhizas transport tremendous quantities of plant-derived carbon below ground and are increasingly recognized for their importance in the creation, structure, and function of soils. Different global carbon models vary widely in their predictions of the dynamics of the terrestrial carbon pool, ranging from a large sink to a large source. This edited book presents a unique synthesis of the influence of environmental change on mycorrhizas across a wide range of ecosystems, as well as a clear examination of new discoveries and challenges for the future, to inform land management practices that preserve or increase below ground carbon storage. - Synthesizes the abundance of research on the influence of environmental change on mycorrhizas across a wide range of ecosystems from a variety of leading international researchers - Focuses on the specific role of mycorrhizal fungi in soil processes, with an emphasis on soil development and carbon storage, including coverage of cutting-edge methods and perspectives - Includes a chapter in each section on future avenues for further study

Download or read book The Effects of Chronic Nitrogen Deposition on the Ectomycorrhizal Community Structure and Function of a Forest Ecosystem with a Mediterranean Climate written by Benjamin A. Waitman and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In this dissertation, I examine how environment-altering anthropogenic disturbances affect the relationship between plants and beneficial soil microbes. Many disturbances change key aspects of the soil environment, directly affecting both plants and soil microbes, and potentially altering plant-microbe interactions. I use a combination of field and greenhouse experiments to compare plant-soil microbe interactions across different levels of environmental disturbance. In Chapter I and II, I used a well-known pollution gradient across montane forests in Southern California to examine how nitrogen (N) deposition alters the structure and function of ectomycorrhizal fungi in forests with a Mediterranean climate. Many studies have identified strong effects of anthropogenic nitrogen deposition on the community composition of ectomycorrhizal fungi in boreal and temperate forest soils. These ecosystems are typically N limited, and it is not clear whether N deposition has similar effects on ectomycorrhizal communities in less productive ecosystems where N may be colimiting to plant productivity along with other resources. I tested the effects of N deposition on ectomycorrhizal communities within forests receiving a range of N deposition in the San Bernardino National Forest of Southern California, where tree growth during the growing season is typically limited by water availability. To determine the effects of N deposition on ectomycorrhizal communities, I sampled both the ectomycorrhizae colonizing the root tips of ponderosa pine and present as fungal hyphae, collectively referred to as mycelium. Ectomycorrhizal fungi present in these samples were identified using PCR based molecular methods. In addition, I tested whether N deposition alters functional traits of ectomycorrhizal communities by assaying the production of a suite of extracellular enzymes that target a range of organic soil nutrients. For enzyme assays, I used ectomycorrhizal colonized root tips collected from forest stands across the N deposition gradient during both dry and wet seasons. Ectomycorrhizal community composition was correlated with N deposition for both colonized root tip and mycelium samples. In addition, mycelium abundance was negatively correlated with soil nitrate concentration. However, the function of ectomycorrhizal communities was not strongly affected by N deposition in this study, and N deposition was much less important to EMF enzyme production than seasonal effects. I found that enzyme production was consistent in most seasons across the N deposition gradient for enzymes that target organic nitrogen sources, organic phosphorus, and recalcitrant carbon sources. Only the production of glycoside hydrolyzing enzymes were positively correlated with N deposition, and only during the wettest sampling period in December. These results confirm that N deposition is changing ectomycorrhizal communities and abundance, even in dry forests where conditions may reduce the relative importance of nitrogen nutrition for forest trees. However, the change in community composition does not appear to result in a change in the capacity of EMF communities to produce extracellular enzymes. In Chapter III, I evaluate the effects of multiple mechanisms of plant soil feedbacks in exotic and native grasses using a greenhouse study in which soil microbial communities, soil organic matter distribution, and nitrification rates were manipulated. Both exotic and native grasses exhibited evidence of negative plant soil feedback, but the results were much stronger in native grasses. In addition, different mechanisms of plant soil feedback were important for exotic and native grasses. Mixing soil profiles, a treatment that redistributed soil resources throughout the soil column, caused exotic grasses to grow significantly more deep roots. As exotic grasses tend to concentrate roots and soil resources in upper soil layers, this result may indicate potential negative feedback under field conditions. Native grass biomass responded positively to sterilization and reduced nitrification. That different feedback mechanisms were important in explaining the plant soil feedback between co-occurring species highlights the value of testing multiple feedback mechanisms and underscores the diversity of changes that exotic species may have on the soil environment.