Arbuscular mycorrhizal fungi (AMF) typically provide a wide range of nutritional benefits to their host plants, and their role in plant water uptake, although still controversial, is often cited as one of the hallmarks of this symbiosis. Less attention has been dedicated to other effects relating to water dynamics that the presence of AMF in soils may have. Evidence that AMF can affect soil hydraulic properties is only beginning to emerge. In one of our recent experiments with dwarf tomato plants, we serendipitously found that the arbuscular mycorrhizal fungus (Rhizophagus irregularis 'PH5') can slightly but significantly reduce water holding capacity (WHC) of the substrate (a sand-zeolite-soil mixture). This was further investigated in a subsequent experiment, but there we found exactly the opposite effect as mycorrhizal substrate retained more water than did the non-mycorrhizal substrate. Because the same substrate was used and other conditions were mostly comparable in the two experiments, we explain the contrasting results by different substrate compaction, most likely caused by different pot shapes. It seems that in compacted substrates, AMF may have no effect upon or even decrease the substrates' WHC. On the other hand, the AMF hyphae interweaving the pores of less compacted substrates may increase the capillary movement of water throughout such substrates and cause slightly more water to remain in the pores after the free water has drained. We believe that this phenomenon is worthy of mycorrhizologists' attention and merits further investigation as to the role of AMF in soil hydraulic properties.

• Klíčová slova
• Arbuscular mycorrhizal fungi, Irrigation, Pot shape, Sand–zeolite–soil mixture, Tomato, Water holding capacity,
• MeSH
• Glomeromycota fyziologie   MeSH
• houby MeSH
• mykorhiza * fyziologie   MeSH
• půda * chemie   MeSH
• půdní mikrobiologie * MeSH
• Solanum lycopersicum mikrobiologie   fyziologie   MeSH
• voda * metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• půda * MeSH
• voda * MeSH

Arbuscular mycorrhizal fungi (AMF) colonize the roots of numerous aquatic and wetland plants, but the establishment and functioning of mycorrhizal symbiosis in submerged habitats have received only little attention. Three pot experiments were conducted to study the interaction of isoetid plants with native AMF. In the first experiment, arbuscular mycorrhizal (AM) symbiosis did not establish in roots of Isoëtes echinospora and I. lacustris, while Littorella uniflora roots were highly colonized. Shoot and root biomass of L. uniflora were, however, not affected by AMF inoculation, and only one of nine AMF isolates significantly increased shoot P concentration. In the second experiment, we compared colonization by three Glomus tetrastratosum isolates of different cultivation history and origin (aquatic versus terrestrial) and their effects on L. uniflora growth and phosphorus nutrition under submerged versus terrestrial conditions. The submerged cultivation considerably slowed, but did not inhibit mycorrhizal root colonization, regardless of isolate identity. Inoculation with any AMF isolate improved plant growth and P uptake under terrestrial, but not submerged conditions. In the final experiment, we compared the communities of AMF established in two cultivation regimes of trap cultures with lake sediments, either submerged on L. uniflora or terrestrial on Zea mays. After 2-year cultivation, we did not detect a significant effect of cultivation regime on AMF community composition. In summary, although submerged conditions do not preclude the development of functional AM symbiosis, the contribution of these symbiotic fungi to the fitness of their hosts seems to be considerably less than under terrestrial conditions.

• Klíčová slova
• Aquatic plants, Arbuscular mycorrhizal symbiosis, Isoetids, Isoëtes, Littorella uniflora, Submerged roots,
• MeSH
• biomasa MeSH
• Glomeromycota * MeSH
• houby MeSH
• kořeny rostlin MeSH
• mykorhiza * MeSH
• symbióza MeSH
• Publikační typ
• časopisecké články MeSH

The arbuscular mycorrhizal (AM) fungi are a globally distributed group of soil organisms that play critical roles in ecosystem function. However, the ecological niches of individual AM fungal taxa are poorly understood. We collected > 300 soil samples from natural ecosystems worldwide and modelled the realised niches of AM fungal virtual taxa (VT; approximately species-level phylogroups). We found that environmental and spatial variables jointly explained VT distribution worldwide, with temperature and pH being the most important abiotic drivers, and spatial effects generally occurring at local to regional scales. While dispersal limitation could explain some variation in VT distribution, VT relative abundance was almost exclusively driven by environmental variables. Several environmental and spatial effects on VT distribution and relative abundance were correlated with phylogeny, indicating that closely related VT exhibit similar niche optima and widths. Major clades within the Glomeraceae exhibited distinct niche optima, Acaulosporaceae generally had niche optima in low pH and low temperature conditions, and Gigasporaceae generally had niche optima in high precipitation conditions. Identification of the realised niche space occupied by individual and phylogenetic groups of soil microbial taxa provides a basis for building detailed hypotheses about how soil communities respond to gradients and manipulation in ecosystems worldwide.

• Klíčová slova
• arbuscular mycorrhizal fungi, ecological niche, molecular taxa, niche optimum, niche width, pH, phylogenetic correlation, temperature,
• MeSH
• ekosystém MeSH
• fylogeneze MeSH
• houby MeSH
• koncentrace vodíkových iontů MeSH
• mykorhiza * MeSH
• půda MeSH
• půdní mikrobiologie MeSH
• teplota MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• půda MeSH

Dispersal of mycorrhizal fungi via animals and the importance for the interacting partners' life history as well as for ecosystems is an understudied topic. In this review, we describe the available evidence and the most important knowledge gaps and finally suggest ways to gain the missing information. So far, 33 articles have been published proving a successful transfer of mycorrhizal propagules by animals. The vast majority of research on invertebrates was focused on arbuscular mycorrhizal (AM) fungi, whereas papers on vertebrates (mainly rodents and artiodactyls) equally addressed ectomycorrhizal (ECM) and AM fungi. Effective dispersal has been mostly shown by the successful inoculation of bait plants and less commonly by spore staining or germination tests. Based on the available data and general knowledge on animal lifestyles, collembolans and oribatid mites may be important in transporting ECM fungal propagules by ectozoochory, whereas earthworms, isopods, and millipedes could mainly transfer AM fungal spores in their gut systems. ECM fungal distribution may be affected by mycophagous dipterans and their hymenopteran parasitoids, while slugs, snails, and beetles could transport both mycorrhizal groups. Vertebrates feeding on fruit bodies were shown to disperse mainly ECM fungi, while AM fungi are transported mostly accidentally by herbivores. The important knowledge gaps include insufficient information on dispersal of fungal propagules other than spores, the role of invertebrates in the dispersal of mycorrhizal fungi, the way in which propagules pass through food webs, and the spatial distances reached by different dispersal mechanisms both horizontally and vertically.

• Klíčová slova
• Arbuscular mycorrhiza, Biodiversity, Dispersal, Ectomycorrhiza, Fungal traits, Zoochory,
• MeSH
• bezobratlí fyziologie   MeSH
• houby fyziologie   MeSH
• mykorhiza fyziologie   MeSH
• potravní řetězec * MeSH
• půdní mikrobiologie MeSH
• symbióza MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

Arbuscular mycorrhizal fungi (AMF) exhibit great potential in heavy-metal immobilization in semi-aquatic habitats. Under high heavy-metal stress, however, the role of AMF is limited, and the detoxification mechanism of AMF in heavy metals' stabilization remains unclear. This study investigated the effects of AMF on a wetland plant (Iris pseudacorus) and chromium (Cr) immobilization at different water depths in semi-aquatic habitats with biochar addition. Results showed that AMF increased the physiological and photosynthetic functions in I. pseudacorus under Cr exposures. Besides, AMF alleviated the accumulation of reactive oxygen species and lipid peroxidation by enhancing the antioxidant enzyme activities. AMF and biochar significantly decreased Cr concentrations in outlet water and increased Cr accumulation in I. pseudacorus. Besides, biochar also vastly improved Cr accumulation in the substrate under the fluctuating water depth. AMF reduced Cr bioavailability in the substrate, with Cr (Ⅵ) concentrations and acid-soluble forms of Cr decreased by 0.3-64.5% and 19.0-40.8%, respectively. Micro-proton-induced X-ray emission was used to determine element localization and revealed that AMF improved the nutrients uptake by wetland plants and inhibited Cr translocation from roots to shoots. Overall, this study demonstrated that the interaction between AMF and biochar could significantly enhance the immobilization of high Cr concentrations in semi-aquatic habitats.

• Klíčová slova
• Arbuscular mycorrhizal fungi, Biochar, Cr immobilization, Water depths, Wetland plants behaviour,
• MeSH
• chrom toxicita   MeSH
• dřevěné a živočišné uhlí MeSH
• ekosystém MeSH
• houby MeSH
• kořeny rostlin mikrobiologie   MeSH
• mykorhiza * MeSH
• rostliny MeSH
• těžké kovy * MeSH
• voda farmakologie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• biochar MeSH Prohlížeč
• chrom MeSH
• dřevěné a živočišné uhlí MeSH
• těžké kovy * MeSH
• voda MeSH

Belowground interactions of plants with other organisms in the rhizosphere rely on extensive small-molecule communication. Chemical signals released from host plant roots ensure the development of beneficial arbuscular mycorrhizal (AM) fungi which in turn modulate host plant growth and stress tolerance. However, parasitic plants have adopted the capacity to sense the same signaling molecules and to trigger their own seed germination in the immediate vicinity of host roots. The contribution of AM fungi and parasitic plants to the regulation of phytohormone levels in host plant roots and root exudates remains largely obscure. Here, we studied the hormonome in the model system comprising tobacco as a host plant, Phelipanche spp. as a holoparasitic plant, and the AM fungus Rhizophagus irregularis. Co-cultivation of tobacco with broomrape and AM fungi alone or in combination led to characteristic changes in the levels of endogenous and exuded abscisic acid, indole-3-acetic acid, cytokinins, salicylic acid, and orobanchol-type strigolactones. The hormonal content in exudates of broomrape-infested mycorrhizal roots resembled that in exudates of infested non-mycorrhizal roots and differed from that observed in exudates of non-infested mycorrhizal roots. Moreover, we observed a significant reduction in AM colonization of infested tobacco plants, pointing to a dominant role of the holoparasite within the tripartite system.

• Klíčová slova
• mycorrhizal fungi, parasitic plants, plant hormones, rhizosphere, root exudates, small-molecule communication, strigolactones,
• MeSH
• chromatografie kapalinová MeSH
• cytokininy metabolismus   MeSH
• heterocyklické sloučeniny tricyklické metabolismus   MeSH
• hmotnostní spektrometrie MeSH
• houby fyziologie   MeSH
• interakce hostitele a patogenu MeSH
• kořeny rostlin metabolismus   mikrobiologie   MeSH
• kyselina abscisová metabolismus   MeSH
• kyselina salicylová metabolismus   MeSH
• kyseliny indoloctové metabolismus   MeSH
• laktony metabolismus   MeSH
• mykorhiza fyziologie   MeSH
• Orobanche růst a vývoj   mikrobiologie   MeSH
• tabák růst a vývoj   mikrobiologie   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• cytokininy MeSH
• GR24 strigolactone MeSH Prohlížeč
• heterocyklické sloučeniny tricyklické MeSH
• indoleacetic acid MeSH Prohlížeč
• kyselina abscisová MeSH
• kyselina salicylová MeSH
• kyseliny indoloctové MeSH
• laktony MeSH

Specific biomarker molecules are increasingly being used for detection and quantification in plant and soil samples of arbuscular mycorrhizal (AM) fungi, an important and widespread microbial guild heavily implicated in transfers of nutrients and carbon between plants and soils and in the maintenance of soil physico-chemical properties. Yet, concerns have previously been raised as to the validity of a range of previously used approaches (e.g., microscopy, AM-specific fatty acids, sterols, glomalin-like molecules, ribosomal DNA sequences), justifying further research into novel biomarkers for AM fungal abundance and/or functioning. Here, we focused on complex polar lipids contained in pure biomass of Rhizophagus irregularis and in nonmycorrhizal and mycorrhizal roots of chicory (Cichorium intybus), leek (Allium porrum), and big bluestem (Andropogon gerardii). The lipids were analyzed by shotgun lipidomics using a high-resolution hybrid mass spectrometer. Size range between 1350 and 1550 Da was chosen for the detection of potential biomarkers among cardiolipins (1,3-bis(sn-3'-phosphatidyl)-sn-glycerols), a specific class of phospholipids. The analysis revealed a variety of molecular species, including cardiolipins containing one or two polyunsaturated fatty acids with 20 carbon atoms each, i.e., arachidonic and/or eicosapentaenoic acids, some of them apparently specific for the mycorrhizal samples. Although further verification using a greater variety of AM fungal species and samples from various soils/ecosystems/environmental conditions is needed, current results suggest the possibility to identify novel biochemical signatures specific for AM fungi within mycorrhizal roots. Whether they could be used for quantification of both root and soil colonization by the AM fungi merits further scrutiny.

• Klíčová slova
• Biomarker, Cardiolipins, Extraradical mycelium, Quantification, Root colonization, Shotgun lipidomics,
• MeSH
• česneky MeSH
• ekosystém MeSH
• houby MeSH
• kardiolipiny MeSH
• kořeny rostlin mikrobiologie   MeSH
• mykorhiza * MeSH
• půda chemie   MeSH
• rostliny MeSH
• uhlík MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• kardiolipiny MeSH
• půda MeSH
• uhlík MeSH

This study investigated the effects of arbuscular mycorrhizal fungi (AMF) colonization on the growth of wetland plants (Glyceria maxima), and treatment performance in constructed wetlands (CWs) under the stress of pharmaceuticals ibuprofen (IBU) and diclofenac (DCF). Results showed that the growth of G. maxima was significantly increased by AMF colonization. AMF significantly increased the activities of antioxidant enzymes (peroxidase and superoxide dismutase) and soluble protein content in wetland plants, but the contents of malondialdehyde and O2•- were reduced. The removal efficiencies of TOC, PO43--P, NH4+-N, and TN were increased in AMF+ treatments by 6%, 11%, 15% and 11%, respectively. AMF increased the removal efficiencies of IBU and DCF by 6-14% and 2-21%, respectively, and reduced the content of their metabolites (2-OH IBU, CA IBU and 4'-OH DCF) in the effluent. Besides, the presence of AMF increased the contents of IBU and DCF in plant roots, while decreased their transportation to shoots. AMF symbiosis decreased the contents of IBU metabolites (2-OH IBU and CA IBU) but increased the contents of DCF metabolite (4'-OH DCF) in the roots of the host plant. In conclusion, these results indicated that AMF plays a promising role in CWs for emerging pollutants removal.

• Klíčová slova
• Arbuscular mycorrhizal fungi, Constructed wetland, Diclofenac, Ibuprofen, Metabolites,
• MeSH
• diklofenak MeSH
• houby MeSH
• ibuprofen MeSH
• kořeny rostlin MeSH
• léčivé přípravky * MeSH
• mokřady MeSH
• mykorhiza * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• diklofenak MeSH
• ibuprofen MeSH
• léčivé přípravky * MeSH

Many orchid species are endangered due to anthropogenic pressures such as habitat destruction and overharvesting, meanwhile, all orchids rely on orchid mycorrhizal fungi (OMF) for seed germination and seedling growth. Therefore, a better understanding of this intimate association is crucial for orchid conservation. Isolation and identification of OMF remain challenging as many fungi are unculturable. In our study, we tested the efficiency of both culture-dependent and culture-independent methods to describe OMF diversity in multiple temperate orchids and assessed any phylogenetic patterns in cultivability. The culture-dependent method involved the cultivation and identification of single pelotons (intracellular hyphal coils), while the culture-independent method used next-generation sequencing (NGS) to identify root-associated fungal communities. We found that most orchid species were associated with multiple fungi, and the orchid host had a greater impact than locality on the variability in fungal communities. The culture-independent method revealed greater fungal diversity than the culture-dependent one, but despite the lower detection, the isolated fungal strains were the most abundant OMF in adult roots. Additionally, the abundance of NGS reads of cultured OTUs was correlated with the extent of mycorrhizal root colonization in orchid plants. Finally, this limited-scale study tentatively suggests that the cultivability character of OMF may be randomly distributed along the phylogenetic trees of the rhizoctonian families.

• Klíčová slova
• Ceratobasidiaceae, Orchidaceae, Serendipitaceae, Tulasnellaceae, culture-independent and -dependent methods, fungal phylogeny, metabarcoding, mycorrhizal fungi,
• Publikační typ
• časopisecké články MeSH

Arbuscular mycorrhizal fungi (AMF) are important symbionts for the majority of terrestrial vascular plants, yet the drivers of the compositional variation in AMF communities need to be better understood. What effects does the ontogenetic stage of host plants have and do these effects differ between plant functional groups? Are the AMF communities modified by the properties of surrounding vegetation, such as the proportion of different functional groups or nonmycorrhizal plants ? We addressed these questions in a temperate grassland and studied AMF communities using next-generation sequencing and light microscopy, evaluating their composition, taxonomic, phylogenetic and functional diversity, functional traits and root colonization levels. We found important differences between AMF communities and their diversity between seedlings and adults which are larger than the differences among host species or between functional groups. The proportion of nonmycorrhizal plants in the surrounding affected AMF community composition and increased its richness. Our results highlight the need for further investigating the existence of a common mycelial networks. The decision to use seedlings for experimental work can affect the results more than the chosen host species.

• Klíčová slova
• arbuscular mycorrhizal fungi (AMF), diversity, forbs, functional traits, grasses, microscopy, next-generation sequencing, nonmycorrhizal plants,
• MeSH
• fylogeneze MeSH
• houby MeSH
• kořeny rostlin MeSH
• mykobiom * MeSH
• mykorhiza * MeSH
• pastviny MeSH
• půda MeSH
• půdní mikrobiologie MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• půda MeSH