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1.
丛枝菌根真菌最新分类系统与物种多样性研究概况 总被引:3,自引:0,他引:3
丛枝菌根真菌(arbuscular mycorrhizal fungi,AMF)是自然界分布最广泛的一类植物共生真菌,能够与大部分高等植物的根系形成共生关系.由于它们在农林、环境等领域的巨大应用潜力,国内外关于AMF物种多样性的研究一直受到较高的关注.然而,AMF专性共生的特征以及研究方法不够理想等因素长期阻碍了AMF物种多样性的研究进展.近年来,研究方法的改进与新技术的应用为AMF物种多样性的研究提供了极好的机遇.简述了AMF的最新分类系统及全球物种数量、AMF物种多样性影响因素以及AMF物种多样性研究方法三个方面的研究进展,并分析了今后在AMF物种多样性相关领域值得关注的研究方向. 相似文献
2.
We investigated the effects of arbuscular mycorrhizal fungal (AMF) species richness and composition on plant community productivity and diversity, and whether AMF mediate plant species coexistence by promoting niche differentiation in phosphorus use. Our experiment manipulated AMF species richness and identity across a range of P conditions in tallgrass prairie mesocosms. We showed that increasing AMF richness promoted plant diversity and productivity, but that this AMF richness effect was small relative to the effects of individual AMF species. We found little support for AMF-facilitated complementarity in P use. Rather, the AMF richness effect appeared to be caused by the inclusion of particular diversity- and productivity-promoting AMF (a sampling effect). Furthermore, the identity of the diversity-promoting fungi changed with P environment, as did the relationship between the diversity-promoting and productivity-promoting benefits of AMF. Our results suggest that plant diversity and productivity are more responsive to AMF identity than to AMF diversity per se, and that AMF identity and P environment can interact in complex ways to alter community-level properties. 相似文献
3.
丛枝菌根真菌物种多样性研究进展 总被引:3,自引:0,他引:3
丛枝菌根真菌(Arbuscular mycorrhizal fungi,AMF)在不同生态系统均发挥至关重要的作用,研究其多样性能够为AMF物种资源的保护和利用提供科学依据。AMF不能被离体纯培养以及自身的高变异性等因素严重阻碍了对其进行深入研究,随着研究方法的不断改进,尤其是新一代测序技术的运用,极大加速了人们对AMF物种多样性的认识。本文主要从AMF分类系统、不同宿主植物和不同生境中的AMF物种多样性及AMF物种多样性研究方法(包括形态鉴定、Sanger测序和高通量测序)方面介绍AMF物种多样性研究进展,并且探讨AMF物种多样性研究中存在的主要问题,认为在今后AMF物种多样性研究中不仅要注重运用新的研究手段,还应该着重解决AMF不能离体纯培养的问题。 相似文献
4.
5.
Mycelium of Arbuscular Mycorrhizal fungi (AMF) from different genera: form, function and detection 总被引:13,自引:2,他引:11
John C. Dodd Claire L. Boddington Alia Rodriguez Carmen Gonzalez-Chavez Irdika Mansur 《Plant and Soil》2000,226(2):131-151
It is often assumed that all species of arbuscular mycorrhizal fungi (AMF) have the same function because of the ubiquity
of the arbuscular mycorrhizal symbiosis and the fact that all AMF occupy the same plant/soil niche. Despite apparent differences
in the timing of evolutionary divergence and the morphological characteristics of AMF from the different genera, the majority
of studies on these fungi use only species of Glomus. There is increasing evidence, however, that the mechanisms involved in the establishment of a mycorrhiza may differ for
species and genera of AMF and influence their subsequent function. The aim of this paper is to highlight the diversity in
the form and function of AMF from different genera, knowledge of which is vital in understanding their ecological roles. Potential
use of biochemical and molecular approaches to detect AMF in planta and ex planta is also discussed.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
6.
Felix Gugerli Roland Brandl Bastien Castagneyrol Alain Franc Hervé Jactel Hans-Peter Koelewijn Francis Martin Martina Peter Karin Pritsch Hilke Schröder Marinus J. M. Smulders Antoine Kremer Birgit Ziegenhagen Evoltree JERA Contributors 《Molecular ecology》2013,22(12):3198-3207
Understanding the interactions of co-occurring species within and across trophic levels provides key information needed for understanding the ecological and evolutionary processes that underlie biological diversity. As genetics has only recently been integrated into the study of community-level interactions, the time is right for a critical evaluation of potential new, gene-based approaches to studying communities. Next-generation molecular techniques, used in parallel with field-based observations and manipulative experiments across spatio-temporal gradients, are key to expanding our understanding of community-level processes. Here, we introduce a variety of ‘-omics’ tools, with recent studies of plant–insect herbivores and of ectomycorrhizal systems providing detailed examples of how next-generation approaches can revolutionize our understanding of interspecific interactions. We suggest ways that novel technologies may convert community genetics from a field that relies on correlative inference to one that reveals causal mechanisms of genetic co-variation and adaptations within communities. 相似文献
7.
丛枝菌根真菌(arbuscular mycorrhizal fungi,AMF)是一类分布广泛的植物根系共生微生物,在促进植物营养吸收、改善土壤结构、调节全球碳氮循环等方面具有重要的生理生态作用。经过一个多世纪的研究,AMF物种多样性及群落生态学研究等已取得了重大成就。AMF目前单列一门球囊霉门(Glomeromycota),全球已发现的形态种约250个;然而,随着AMF分子多样性的研究深入,越来越多的证据暗示了AMF可能有惊人的物种多样性。AMF群落多样性及物种组成受时空、宿主以及土壤因子的显著影响,但随机过程在AMF群落构建中也发挥了重要作用。综述了AMF的物种多样性及群落构建机制研究进展,并对今后这两方面的研究方向提出了展望。 相似文献
8.
Genetic variability in a population of arbuscular mycorrhizal fungi causes variation in plant growth 总被引:5,自引:1,他引:4
Different species of arbuscular mycorrhizal fungi (AMF) alter plant growth and affect plant coexistence and diversity. Effects of within-AMF species or within-population variation on plant growth have received less attention. High genetic variation exists within AMF populations. However, it is unknown whether genetic variation contributes to differences in plant growth. In our study, a population of AMF was cultivated under identical conditions for several generations prior to the experiments thus avoiding environmental maternal effects. We show that genetically different Glomus intraradices isolates from one AMF population significantly alter plant growth in an axenic system and in greenhouse experiments. Isolates increased or reduced plant growth meaning that plants potentially receive benefits or are subject to costs by forming associations with different individuals in the AMF population. This shows that genetic variability in AMF populations could affect host-plant fitness and should be considered in future research to understand these important soil organisms. 相似文献
9.
Variable responses of old-field perennials to arbuscular mycorrhizal fungi and phosphorus source 总被引:4,自引:0,他引:4
If arbuscular mycorrhizal fungi (AMF) promote phosphorus partitioning of plant hosts, they could provide one mechanism for
the maintenance of plant community diversity. We investigated whether AMF improved the ability of old field perennials to
grow on a range of phosphorus sources and whether AMF facilitated differential performance of plant species on different phosphorus
sources (phosphorus niche partitioning). We manipulated form of phosphorus (control versus different inorganic and organic
sources) and AM fungal species (control versus four individual AMF species or an AMF community) for five old field perennials
grown in a greenhouse in individual culture. Based on biomass after four months of growth, we found no evidence for phosphorus
niche partitioning. Rather, we found that effects of AMF varied from parasitic to mutualistic depending on plant species,
AMF species, and phosphorus source (significant Plant × Fungus × Phosphorus interaction). Our results suggest that the degree
of AMF benefit to a plant host depends not only on AMF species, plant species, and soil phosphorus availability (as has also
been found in other work), but can also depend on the form of soil phosphorus. Thus, the position of any AMF species along
the mutualism to parasitism continuum may be a complex function of local conditions, and this has implications for understanding
plant competitive balance in the field. 相似文献
10.
Despite the important ecosystem role played by arbuscular mycorrhizal fungi (AMF), little is known about spatial and temporal variation in soil AMF communities. We used pyrosequencing to characterise AMF communities in soil samples (n = 44) from a natural forest ecosystem. Fungal taxa were identified by BLAST matching of reads against the MaarjAM database of AMF SSU rRNA gene diversity. Sub-sampling within our dataset and experimental shortening of a set of long reads indicated that our approaches to taxonomic identification and diversity analysis were robust to variations in pyrosequencing read length and numbers of reads per sample. Different forest plots (each 10×10 m and separated from one another by 30 m) contained significantly different soil AMF communities, and the pairwise similarity of communities decreased with distance up to 50 m. However, there were no significant changes in community composition between different time points in the growing season (May-September). Spatial structure in soil AMF communities may be related to the heterogeneous vegetation of the natural forest study system, while the temporal stability of communities suggests that AMF in soil represent a fairly constant local species pool from which mycorrhizae form and disband during the season. 相似文献
11.
Noé Manuel Montaño Alejandro Alarcón Sara Lucía Camargo-Ricalde Laura Verónica Hernández-Cuevas Javier Álvarez-Sánchez Ma. del Carmen A. González-Chávez Mayra E. Gavito Irene Sánchez-Gallen José Ramos-Zapata Patricia Guadarrama Ignacio E. Maldonado-Mendoza Silvia Castillo-Argüero Rosalva García-Sánchez Dora Trejo Ronald Ferrera-Cerrato 《Symbiosis (Philadelphia, Pa.)》2012,57(3):111-126
This review analyzes the historical development and advances of the research on arbuscular mycorrhizal fungi (AMF) in Mexico, as well as the prospects for future research. AMF-research has been focused on studying both diversity and functionality in several ecosystems of Mexico, but mainly in the tropical dry and rainy ecosystems, and the agricultural systems. In Mexico, 95 species of AMF have been recorded, representing 41% of the known species worldwide. The functional effects of AMF colonization have been examined in approximately 10% of the known host plants, but greenhouse studies continue to dominate over those conducted under field conditions. Even though research to date has been at the organismic level, further effort is needed due to the high plant diversity in Mexico. Studies on AMF biomass under field conditions and more taxonomic determination are required based on morphological features, biochemical determinations (fatty acids) and molecular tools. In addition, ecophysiological and ecological in situ studies would help in understanding the relationships among AMF, soil fauna, nutrients, and host plants. The contribution of AMF to ecosystemic processes is a priority line of research that requires an integrated approach (inter- and multidisciplinary) in order to define the role of AM symbioses for biogeochemical models. The creation of a Mexican mycorrhizal research network has and will help to identify the main challenges. Generating similar research protocols, and sharing databases and experience will assist mycorrhizologists working under the diverse financial and ecological contexts that is to be found in Mexico and Latin America. 相似文献
12.
E. Nichols T. A. Gardner C. A. Peres S. Spector The Scarabaeinae Research Network 《Oikos》2009,118(4):481-487
Biodiversity loss can precipitate extinction cascades and impair ecological processes. These 'downstream' effects will be exacerbated if functionally important taxa are tightly linked with species threatened by extinction or population decline. We review the current evidence that such a scenario is currently playing out in the linked declines of persistently hunted mammal populations and the dung beetles communities (Coleoptera: Scarabaeidae: Scarabaeinae) that depend on them for adult and larval food resources. Through a close evolutionary association, mammal assemblages have played a fundamental role in structuring extant dung beetle communities. Today many game mammal species' populations are severely depleted by subsistence or commercial hunting, especially in tropical forest systems. Multiple lines of evidence from temperate and tropical systems indicate that the regional-scale decline or extirpation of medium and large bodied mammal faunas can severely disrupt the diversity and abundance of dung beetle communities through alterations in the composition and availability of dung resources. These observed community disassemblies have significant short- and long-term implications for the maintenance of key ecosystem processes including nutrient recycling and secondary seed dispersal. Identifying the species- and community-level traits that buffer or exacerbate these species and functional responses is essential if we are to develop a better understanding of the cascading ecological consequences of hunting in tropical forests. 相似文献
13.
Giovanni Russildi Víctor Arroyo-Rodríguez Omar Hernández-Ordóñez Eduardo Pineda Víctor H. Reynoso 《Biodiversity and Conservation》2016,25(2):375-392
The rapid loss and degradation of tropical forests threatens the maintenance of biodiversity across different spatial scales. Nevertheless, the extirpation and population decline of some disturbance-sensitive species may be compensated for by colonization and proliferation of disturbance-adapted species, thus allowing distributions of community-level attributes (e.g., abundance and diversity) to be preserved in human-modified tropical landscapes. To test this poorly assessed hypothesis we evaluated species- and community-level responses of amphibians and reptiles to differences in forest patch (patch size, shape, and distance to water bodies) and landscape metrics (old-growth forest cover, degree of fragmentation, and matrix composition) in the fragmented Lacandona rainforest, Mexico. We found that the abundance of several amphibian and reptile species was strongly associated with forest patch and landscape attributes, being particularly higher in larger patches surrounded by a greater forest cover. Such changes at the species level generated notable changes in reptile communities. In particular, the abundance, diversity, and evenness of reptile communities were strongly related to patch size, patch shape, and matrix composition. Yet, because of compensatory dynamics in amphibians, this group showed weak responses at the community level. Despite such compensatory dynamics, our results indicate that forest loss at the patch and landscape levels represents the main threat to both amphibians and reptiles, thus indicating that to preserve herpetological communities in this biodiversity hotspot, conservation initiatives should be focused on preventing further deforestation. 相似文献
14.
Community structure of arbuscular mycorrhizal fungi (AMF), evaluated as spore samples and mycorrhizal roots of four herbaceous
plant species, was investigated at different altitudes in a primary successional volcanic desert on Mount Fuji using molecular
methods (fragment and sequence analysis of the large ribosomal subunit RNA gene). In total, 17 different AMF clades were identified,
and most were members of the Glomaceae, Acaulosporaceae, and Gigasporaceae. The AMF community structures detected by spore
sampling were inconsistent with those from plant roots. Of all AMF clades, six (35.3%) were detected only on the basis of
spores, six (35.3%) only in roots, and five corresponded to both spores and roots (29.4%). Although an Acaulospora species was the most dominant among spores (67.1%), it accounted for only 6.8% in root samples. A species analysis of AMF
communities at different altitudes demonstrated that AMF species diversity increased as altitude decreased and that the species
enrichment at lower altitudes resulted from the addition of new species rather than species replacement. The inconsistencies
in the species composition of spore communities with those in roots and the change in species diversity with altitude are
discussed. 相似文献
15.
16.
Although it has become increasingly clear that arbuscular mycorrhizal fungi (AMF) play important roles in population, community,
and ecosystem ecology, there is limited information on the spatial structure of the community composition of AMF in the field.
We assessed small-scale spatial variation in the abundance and molecular diversity of AMF in a calcareous fen, where strong
underlying environmental gradients such as depth to water table may influence AMF. Throughout an intensively sampled 2 × 2 m
plot, we assessed AMF inoculum potential at a depth of 0–6 and 6–12 cm and molecular diversity of the AMF community using
terminal restriction fragment length polymorphism of 18S rDNA. Inoculum potential was only significantly spatially autocorrelated
at a depth of 6–12 cm and was significantly positively correlated with depth to water table at both depths. Molecular diversity
of the AMF community was highly variable within the plot, ranging from 2–14 terminal restriction fragments (T-RFs) per core,
but the number of T-RFs did not relate to water table or plant species richness. Plant community composition was spatially
autocorrelated at small scales, but AMF community composition showed no significant spatial autocorrelation. Saturated soils
of calcareous fens contain many infective AMF propagules and the abundance and diversity of AMF inoculum is patchy over small
spatial scales.
An erratum to this article can be found at 相似文献
17.
Herbert Stockinger Marine Peyret-Guzzon Sally Koegel Marie-Lara Bouffaud Dirk Redecker 《PloS one》2014,9(10)
Due to the potential of arbuscular mycorrhizal fungi (AMF, Glomeromycota) to improve plant growth and soil quality, the influence of agricultural practice on their diversity continues to be an important research question. Up to now studies of community diversity in AMF have exclusively been based on nuclear ribosomal gene regions, which in AMF show high intra-organism polymorphism, seriously complicating interpretation of these data. We designed specific PCR primers for 454 sequencing of a region of the largest subunit of RNA polymerase II gene, and established a new reference dataset comprising all major AMF lineages. This gene is known to be monomorphic within fungal isolates but shows an excellent barcode gap between species. We designed a primer set to amplify all known lineages of AMF and demonstrated its applicability in combination with high-throughput sequencing in a long-term tillage experiment. The PCR primers showed a specificity of 99.94% for glomeromycotan sequences. We found evidence of significant shifts of the AMF communities caused by soil management and showed that tillage effects on different AMF taxa are clearly more complex than previously thought. The high resolving power of high-throughput sequencing highlights the need for quantitative measurements to efficiently detect these effects. 相似文献
18.
Herein we review theoretical and methodological considerations important for finding and delimiting cryptic species of parasites (species that are difficult to recognize using traditional systematic methods). Applications of molecular data in empirical investigations of cryptic species are discussed from an historical perspective, and we evaluate advantages and disadvantages of approaches that have been used to date. Developments concerning the theory and practice of species delimitation are emphasized because theory is critical to interpretation of data. The advantages and disadvantages of different molecular methodologies, including the number and kind of loci, are discussed relative to tree-based approaches for detecting and delimiting cryptic species. We conclude by discussing some implications that cryptic species have for research programmes in parasitology, emphasizing that careful attention to the theory and operational practices involved in finding, delimiting, and describing new species (including cryptic species) is essential, not only for fully characterizing parasite biodiversity and broader aspects of comparative biology such as systematics, evolution, ecology and biogeography, but to applied research efforts that strive to improve development and understanding of epidemiology, diagnostics, control and potential eradication of parasitic diseases. 相似文献
19.
丛枝菌根真菌(AMF)在自然界分布广泛,能与大部分维管植物的根系形成菌根共生体。它们在调节植物群落结构和全球的碳、氮、磷循环等方面发挥着重要的生态功能,也是农林、环境领域最具应用前景的微生物类群。受限于培养方法、研究手段等,长期以来对AMF基因组、转录组特征的认识非常有限。最近10年,AMF基因组和转录组的相关研究在高通量测序技术的推动下取得了较快发展;研究结果也显著提高了对AMF遗传发育、代谢生理、共生机制等的认识。本文综述了目前已完成测序的AMF种类的基因组、转录组信息。结果发现,已测序的AMF种类普遍具有基因组大、转座子丰富、AT碱基含量高、含大量未知功能基因与特异性基因、缺少部分共生相关基因等特点。在转录层面,总结了不同AMF种类、AMF不同共生结构、共生阶段以及与不同寄主植物共生时的转录本特征。结果发现,不同种类AMF的转录本大小差异明显。不同共生阶段或不同共生结构中的AMF转录本也具有较大的差异,且差异表达的基因大部分与养分交易、信号转导等密切相关。相比之下,同种AMF与不同寄主植物共生时的转录本表现出较高的保守性。最后,本文提出了本领域需要重点关注的研究方向,包括AMF纯培养技术的革新、AMF基因功能的解析、非模式AMF类群的研究以及对AMF蛋白组的研究。 相似文献
20.
Global sampling of plant roots expands the described molecular diversity of arbuscular mycorrhizal fungi 总被引:2,自引:0,他引:2
Maarja Öpik Martin Zobel Juan J. Cantero John Davison José M. Facelli Inga Hiiesalu Teele Jairus Jesse M. Kalwij Kadri Koorem Miguel E. Leal Jaan Liira Madis Metsis Valentina Neshataeva Jaanus Paal Cherdchai Phosri Sergei Põlme Ülle Reier Ülle Saks Heidy Schimann Odile Thiéry Martti Vasar Mari Moora 《Mycorrhiza》2013,23(5):411-430
We aimed to enhance understanding of the molecular diversity of arbuscular mycorrhizal fungi (AMF) by building a new global dataset targeting previously unstudied geographical areas. In total, we sampled 96 plant species from 25 sites that encompassed all continents except Antarctica. AMF in plant roots were detected by sequencing the nuclear SSU rRNA gene fragment using either cloning followed by Sanger sequencing or 454-sequencing. A total of 204 AMF phylogroups (virtual taxa, VT) were recorded, increasing the described number of Glomeromycota VT from 308 to 341 globally. Novel VT were detected from 21 sites; three novel but nevertheless widespread VT (Glomus spp. MO-G52, MO-G53, MO-G57) were recorded from six continents. The largest increases in regional VT number were recorded in previously little-studied Oceania and in the boreal and polar climatic zones — this study providing the first molecular data from the latter. Ordination revealed differences in AM fungal communities between different continents and climatic zones, suggesting that both biogeographic history and environmental conditions underlie the global variation of those communities. Our results show that a considerable proportion of Glomeromycota diversity has been recorded in many regions, though further large increases in richness can be expected in remaining unstudied areas. 相似文献