Phosphorus (P) for carbon (C) exchange is the pivotal function of arbuscular mycorrhiza (AM), but how this exchange varies with soil P availability and among co-occurring plants in complex communities is still largely unknown. We collected intact plant communities in two regions differing c. 10-fold in labile inorganic P. After a 2-month glasshouse incubation, we measured 32P transfer from AM fungi (AMF) to shoots and 13C transfer from shoots to AMF using an AMF-specific fatty acid. AMF communities were assessed using molecular methods. AMF delivered a larger proportion of total shoot P in communities from high-P soils despite similar 13C allocation to AMF in roots and soil. Within communities, 13C concentration in AMF was consistently higher in grass than in blanketflower (Gaillardia aristata Pursh) roots, that is P appeared more costly for grasses. This coincided with differences in AMF taxa composition and a trend of more vesicles (storage structures) but fewer arbuscules (exchange structures) in grass roots. Additionally, 32P-for-13C exchange ratios increased with soil P for blanketflower but not grasses. Contrary to predictions, AMF transferred proportionally more P to plants in communities from high-P soils. However, the 32P-for-13C exchange differed among co-occurring plants, suggesting differential regulation of the AM symbiosis.
- Klíčová slova
- P‐for‐C exchange ratio, arbuscular mycorrhiza, resource allocation, soil extractable P, symbiosis,
- MeSH
- fosfor * metabolismus MeSH
- izotopy uhlíku MeSH
- kořeny rostlin mikrobiologie metabolismus MeSH
- lipnicovité metabolismus MeSH
- mykorhiza * fyziologie metabolismus MeSH
- půda * chemie MeSH
- rostliny metabolismus mikrobiologie MeSH
- uhlík * metabolismus MeSH
- výhonky rostlin metabolismus MeSH
- životní prostředí MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- fosfor * MeSH
- izotopy uhlíku MeSH
- půda * MeSH
- uhlík * MeSH
It is well understood that agricultural management influences arbuscular mycorrhizal (AM) fungi, but there is controversy about whether farmers should manage for AM symbiosis. We assessed AM fungal communities colonizing wheat roots for three consecutive years in a long-term (> 14 yr) tillage and fertilization experiment. Relationships among mycorrhizas, crop performance, and soil ecosystem functions were quantified. Tillage, fertilizers and continuous monoculture all reduced AM fungal richness and shifted community composition toward dominance of a few ruderal taxa. Rhizophagus and Dominikia were depressed by tillage and/or fertilization, and their abundances as well as AM fungal richness correlated positively with soil aggregate stability and nutrient cycling functions across all or no-tilled samples. In the field, wheat yield was unrelated to AM fungal abundance and correlated negatively with AM fungal richness. In a complementary glasshouse study, wheat biomass was enhanced by soil inoculum from unfertilized, no-till plots while neutral to depressed growth was observed in wheat inoculated with soils from fertilized and conventionally tilled plots. This study demonstrates contrasting impacts of low-input and conventional agricultural practices on AM symbiosis and highlights the importance of considering both crop yield and soil ecosystem functions when managing mycorrhizas for more sustainable agroecosystems.
- Klíčová slova
- ecosystem services, fertilization, multifunctionality, mycorrhizal fungi, soil aggregation, sustainable agroecosystems, tillage,
- MeSH
- biodiverzita MeSH
- biomasa MeSH
- časové faktory MeSH
- ekosystém * MeSH
- kořeny rostlin mikrobiologie MeSH
- mykorhiza * fyziologie MeSH
- průmyslová hnojiva * MeSH
- pšenice * mikrobiologie růst a vývoj fyziologie MeSH
- půda * chemie MeSH
- půdní mikrobiologie * MeSH
- zemědělské plodiny * mikrobiologie růst a vývoj MeSH
- zemědělství metody MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- průmyslová hnojiva * MeSH
- půda * MeSH
CitCAT1 and CitCAT2 were cloned and highly expressed in mature leaves. High temperatures up-regulated CitCAT1 expression, while low temperatures and Diversispora versiformis up-regulated CitCAT2 expression, maintaining a low oxidative damage. Catalase (CAT), a tetrameric heme-containing enzyme, removes hydrogen peroxide (H2O2) to maintain low oxidative damage in plants exposed to environmental stress. This study aimed to clone CAT genes from Citrus sinensis cv. "Oita 4" and analyze their expression patterns in response to environmental stress, exogenous abscisic acid (ABA), and arbuscular mycorrhizal fungal inoculation. Two CAT genes, CitCAT1 (NCBI accession: PP067858) and CitCAT2 (NCBI accession: PP061394) were cloned, and the open reading frames of their proteins were 1479 bp and 1539 bp, respectively, each encoding 492 and 512 amino acids predicted to be localized in the peroxisome, with CitCAT1 being a stable hydrophilic protein and CitCAT2 being an unstable hydrophilic protein. The similarity of their amino acid sequences reached 83.24%, and the two genes were distantly related. Both genes were expressed in stems, leaves, flowers, and fruits, accompanied by the highest expression in mature leaves. In addition, CitCAT1 expression was mainly up-regulated by high temperatures (37 °C), exogenous ABA, and PEG stress within a short period of time, whereas CitCAT2 expression was up-regulated by exogenous ABA and low-temperature (4 °C) stress. Low temperatures (0 °C) for 12 h just up-regulated CitCAT2 expression in Diversispora versiformis-inoculated plants, and D. versiformis inoculation up-regulated CitCAT2 expression, along with lower hydrogen peroxide and malondialdehyde levels in mycorrhizal plants at low temperatures. It is concluded that CitCAT2 has an important role in resistance to low temperatures as well as mycorrhizal enhancement of host resistance to low temperatures.
- Klíčová slova
- Antioxidase, Catalase, Citrus, Hydrogen peroxide, Low temperatures, Mycorrhiza,
- MeSH
- fyziologický stres genetika MeSH
- houby * MeSH
- klonování DNA MeSH
- mykorhiza * fyziologie MeSH
- peroxid vodíku MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- peroxid vodíku MeSH
The ectomycorrhizal fungi Tuber melanosporum Vittad. and Tuber aestivum Vittad. produce highly valuable truffles, but little is known about the soil fungal communities associated with these truffle species in places where they co-occur. Here, we compared soil fungal communities present in wild and planted truffle sites, in which T. melanosporum and T. aestivum coexist, in Mediterranean and temperate regions over three sampling seasons spanning from 2018 to 2019. We showed that soil fungal community composition and ectomycorrhizal species composition are driven by habitat type rather than climate regions. Also, we observed the influence of soil pH, organic matter content and C:N ratio structuring total and ectomycorrhizal fungal assemblages. Soil fungal communities in wild sites revealed more compositional variability than those of plantations. Greater soil fungal diversity was found in temperate compared to Mediterranean sites when considering all fungal guilds. Ectomycorrhizal diversity was significantly higher in wild sites compared to plantations. Greater mould abundance at wild sites than those on plantation was observed while tree species and seasonal effects were not significant predictors in fungal community structure. Our results suggested a strong influence of both ecosystem age and management on the fungal taxa composition in truffle habitats.
- Klíčová slova
- Fungal diversity, Soil fungi, T. aestivum, T. melanosporum, Truffle ecology, Truffle plantation,
- MeSH
- ekosystém MeSH
- mykobiom * MeSH
- mykorhiza * MeSH
- půda MeSH
- půdní mikrobiologie MeSH
- stromy MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- půda MeSH
Arbuscular mycorrhizal fungi (AMF) can increase plant tolerance and/or resistance to pests such as the root-knot nematode Meloidogyne incognita. However, the ameliorative effects may depend on AMF species. The aim of this work was therefore to evaluate whether four AMF species differentially affect plant performance in response to M. incognita infection. Tomato plants grown in greenhouse conditions were inoculated with four different AMF isolates (Claroideoglomus claroideum, Funneliformis mosseae, Gigaspora margarita, and Rhizophagus intraradices) and infected with 100 second stage juveniles of M. incognita at two different times: simultaneously or 2 weeks after the inoculation with AMF. After 60 days, the number of galls, egg masses, and reproduction factor of the nematodes were assessed along with plant biomass, phosphorus (P), and nitrogen concentrations in roots and shoots and root colonization by AMF. Only the simultaneous nematode inoculation without AMF caused a large reduction in plant shoot biomass, while all AMF species were able to ameliorate this effect and improve plant P uptake. The AMF isolates responded differently to the interaction with nematodes, either increasing the frequency of vesicles (C. claroideum) or reducing the number of arbuscules (F. mosseae and Gi. margarita). AMF inoculation did not decrease galls; however, it reduced the number of egg masses per gall in nematode simultaneous inoculation, except for C. claroideum. This work shows the importance of biotic stress alleviation associated with an improvement in P uptake and mediated by four different AMF species, irrespective of their fungal root colonization levels and specific interactions with the parasite.
- Klíčová slova
- Arbuscular mycorrhizal fungi, Biological control, Plant nutrition, Root knot nematodes,
- MeSH
- Glomeromycota * fyziologie MeSH
- kořeny rostlin mikrobiologie MeSH
- mykorhiza * fyziologie MeSH
- rostliny MeSH
- Solanum lycopersicum * MeSH
- Tylenchoidea * MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
We have investigated whether mycobiont identity and environmental conditions affect morphology and physiology of the chlorophyllous orchid: Cremastra variabilis. This species grows in a broad range of environmental conditions and associates with saprotrophic rhizoctonias including Tulasnellaceae and saprotrophic non-rhizoctonian fungi from the family Psathyrellaceae. We cultured the orchid from seeds under aseptic culture conditions and subsequently inoculated the individuals with either a Tulasnellaceae or a Psathyrellaceae isolate. We observed underground organ development of the inoculated C. variabilis plants and estimated their nutritional dependency on fungi using stable isotope abundance. Coralloid rhizome development was observed in all individuals inoculated with the Psathyrellaceae isolate, and 1-5 shoots per seedling grew from the tip of the coralloid rhizome. In contrast, individuals associated with the Tulasnellaceae isolate did not develop coralloid rhizomes, and only one shoot emerged per plantlet. In darkness, δ13C enrichment was significantly higher with both fungal isolates, whereas δ15N values were only significantly higher in plants associated with the Psathyrellaceae isolate. We conclude that C. variabilis changes its nutritional dependency on fungal symbionts depending on light availability and secondly that the identity of fungal symbiont influences the morphology of underground organs.
- Klíčová slova
- Cremastra variabilis, Coralloid rhizome, Orchidaceae, Stable isotope, Symbiotic culture,
- MeSH
- Agaricales * MeSH
- Basidiomycota * MeSH
- lidé MeSH
- mykorhiza * fyziologie MeSH
- Orchidaceae * mikrobiologie MeSH
- semenáček mikrobiologie MeSH
- symbióza MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Arbuscular mycorrhizal fungi (AMF) and plant growth-promoting bacteria enhance plant tolerance to abiotic stress and promote plant growth in contaminated soil. However, the interaction mechanism between rhizosphere microbial communities under chromium (Cr) stress remains unclear. This study conducted a greenhouse pot experiment and metagenomics analysis to reveal the comprehensive effects of the interaction between AMF (Rhizophagus intraradices) and nitrogen-N metabolizing plant growth promoters on the growth of Iris tectorum. The results showed that AMF significantly increased the biomass and nutrient levels of I. tectorum in contaminated soil and decreased the content of Cr in the soil. Metagenomics analysis revealed that the structure and composition of the rhizosphere microbial community involved in nitrogen metabolism changed significantly after inoculation with AMF under Cr stress. Functional genes related to soil nitrogen mineralization (gltB, gltD, gdhA, ureC, and glnA), nitrate reduction to ammonium (nirB, nrfA, and nasA), and soil nitrogen assimilation (NRT, nrtA, and nrtC) were up-regulated in the N-metabolizing microbial community. In contrast, the abundance of functional genes involved in denitrification (nirK and narI) was down-regulated. In addition, the inoculation of AMF regulates the synergies between the N-metabolic rhizosphere microbial communities and enhances the complexity and stability of the rhizosphere ecological network. This study provides a basis for improving plant tolerance to heavy metal stress by regulating the functional abundance of N-metabolizing plant growth-promoting bacteria through AMF inoculation. It helps to understand the potential mechanism of wetland plant remediation of Cr-contaminated soil.
- Klíčová slova
- Cr stress, Functional gene, Iris tectorum, Metagenome, Nitrogen metabolism, Rhizophagus intraradices,
- MeSH
- Bacteria MeSH
- chrom metabolismus MeSH
- dusík metabolismus MeSH
- houby MeSH
- Iris (rostlina) * genetika MeSH
- kořeny rostlin MeSH
- mykorhiza * metabolismus MeSH
- půda chemie MeSH
- rostliny MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- chrom MeSH
- dusík MeSH
- půda MeSH
Arsenic (As) is a toxic metalloid that poses a potential risk to the environment and human health. In this study, drinking water treatment residue (DWTR) and ceramsite-based vertical flow constructed wetlands (VFCWs) were built to purify As-containing wastewater. As a method of bioaugmentation, arbuscular mycorrhizal fungi (AMF) was inoculated to Pteris vittata roots to enhance the As removal of the VFCWs. The results showed that the As removal rates reached 87.82-94.29% (DWTR) and 33.28-58.66% (ceramsite). DWTR and P. vittata contributed 64.33-72.07% and 7.57-29% to the removal of As, while AMF inoculation intensified the As accumulation effect of P. vittata. Proteobacteria, the main As3+ oxidizing bacteria in the aquatic systems, dominated the microbial community, occupying 72.41 ± 7.76%. AMF inoculation increased As-related functional genes abundance in DWTR-based wetlands and provided a reliable means of arsenic resistance in wetlands. These findings indicated that the DWTR-based VFCWs with AMF inoculated P. vittata had a great purification effect on As-containing wastewater, providing a theoretical basis for the application of DWTR and AMF for As removal in constructed wetlands.
- Klíčová slova
- Arbuscular mycorrhizal fungi, Arsenic functional gene, Arsenic pollution, Drinking water treatment residue, Vertical flow constructed wetlands,
- MeSH
- arsen * MeSH
- kořeny rostlin mikrobiologie MeSH
- lidé MeSH
- mokřady MeSH
- mykorhiza * MeSH
- odpadní voda MeSH
- pitná voda * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- arsen * MeSH
- odpadní voda MeSH
- pitná voda * MeSH
Mycorrhizae, a form of plant-fungal symbioses, mediate vegetation impacts on ecosystem functioning. Climatic effects on decomposition and soil quality are suggested to drive mycorrhizal distributions, with arbuscular mycorrhizal plants prevailing in low-latitude/high-soil-quality areas and ectomycorrhizal (EcM) plants in high-latitude/low-soil-quality areas. However, these generalizations, based on coarse-resolution data, obscure finer-scale variations and result in high uncertainties in the predicted distributions of mycorrhizal types and their drivers. Using data from 31 lowland tropical forests, both at a coarse scale (mean-plot-level data) and fine scale (20 × 20 metres from a subset of 16 sites), we demonstrate that the distribution and abundance of EcM-associated trees are independent of soil quality. Resource exchange differences among mycorrhizal partners, stemming from diverse evolutionary origins of mycorrhizal fungi, may decouple soil fertility from the advantage provided by mycorrhizal associations. Additionally, distinct historical biogeographies and diversification patterns have led to differences in forest composition and nutrient-acquisition strategies across three major tropical regions. Notably, Africa and Asia's lowland tropical forests have abundant EcM trees, whereas they are relatively scarce in lowland neotropical forests. A greater understanding of the functional biology of mycorrhizal symbiosis is required, especially in the lowland tropics, to overcome biases from assuming similarity to temperate and boreal regions.
Treatment of petroleum-contaminated soil to a less toxic medium via physical and chemical treatment is too costly and requires posttreatment. This review focuses on the employment of phytoremediation and mycoremediation technologies in cleaning hydrocarbon-contaminated soil which is currently rare. It is considered environmentally beneficial and possibly cost-effective as it implements the synergistic interaction between plants and biosurfactant producing mycorrhiza to degrade hydrocarbon contaminants. This review also covers possible sources of hydrocarbon pollution in water and soil, toxicity effects, and current technologies for hydrocarbon removal and degradation. In addition to these problems, this review also discusses the challenges and opportunities of transforming the resultant treated sludge and treating plants into potential by-products for a higher quality of life for future generations.
- Klíčová slova
- Biosurfactant, Mycorrhiza, Petroleum, Synergistic, Technology, Toxicity,
- MeSH
- biodegradace MeSH
- kvalita života MeSH
- látky znečišťující půdu * analýza MeSH
- mykorhiza * metabolismus MeSH
- půda MeSH
- půdní mikrobiologie MeSH
- ropa * metabolismus MeSH
- rostliny metabolismus MeSH
- uhlovodíky metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- Názvy látek
- látky znečišťující půdu * MeSH
- půda MeSH
- ropa * MeSH
- uhlovodíky MeSH
