Search Results (379)

Arbuscular mycorrhizal fungi (AMF) taxa, glomalin protein, and hyphal density are potential indicators of soil functionality of temperate grasslands in marginal environments subject to grazing over the years. This study evaluated how the AMF community composition, glomalin protein, and hyphal density vary in response to grazing intensity (low or high) and seasonality (spring and autumn) in sodic soils of Argentinian temperate grasslands. The AMF community was dominated by Glomeraceae species. Funneliformis geosporus and Glomus brohultii were the most abundant in both seasons and all grasslands. No AMF species were associated with a particular grazing intensity. However, Entrophospora etunicata, Glomus fuegianum, Septoglomus constrictum, and Acaulospora sp. occurred only in spring, and no species were exclusive to autumn. Hyphal density was highest in grasslands with low grazing intensity and can be considered an indicator of soil functionality. Glomalin protein was the highest in spring in all grasslands. The lower grazing intensity in grasslands with poor livestock control showed no changes in AMF diversity. The AMF community showed high adaptation to soil conditions, indicating high resilience. We concluded that longer periods of controlled grazing management are needed to improve soil conditions and, consequently, change the AMF species composition. Full article

Ericoid mycorrhizal fungi (EMF) enhance plant fitness and metabolic regulations in nutrient-poor soils, though the mechanisms diving these interactions require further elucidation. This study investigated the physiological and metabolic responses of blueberry seedlings following 2- and 3-weeks inoculation with Oidiodendron maius H14. The results indicated that EMF could significantly increases plant biomass, improve the accumulation of osmoregulatory substances in leaves. Additionally, the colonization rate of EMF are 26.18% and 30.22% after 2- and 3-weeks, respectively. The Metabolomics analysis identified 758 (593 up- and 165 down-regulated) and 805 (577 up- and 228 down-regulated) differential metabolites in roots at 2- and 3-weeks inoculation with O. maius H14, respectively. KEGG pathway annotation revealed that O. maius H14 triggered various amino acid metabolism pathways, including tryptophan metabolism and arginine and proline metabolism. These findings suggested that O. maius H14 stimulated root-specific biosynthesis of growth-promoting compounds and antimicrobial compounds. Concomitant downregulation of stress-associated genes and upregulation of glutamine synthetase suggest EMF modulates host defense responses to facilitate symbiosis. Thus, our results demonstrated that O. maius H14 orchestrates a metabolic reprogramming in blueberry roots, enhancing growth and stress tolerance through coordinated changes in primary and specialized metabolism, which could inform strategies for improving symbiosis and metabolic engineering in horticultural practices. Full article

Phosphorus (P) availability is a major constraint on plant growth in many forest ecosystems, yet the strategies by which different tree species acquire and utilize various forms of soil phosphorus remain poorly understood. This study investigated how coexisting tree species with contrasting mycorrhizal types, specifically arbuscular mycorrhizal (AM) and ectomycorrhizal (ECM) associations, respond to different phosphorus forms under field conditions. An in situ root bag experiment was conducted using four phosphorus treatments (control, inorganic, organic, and mixed phosphorus) across four subtropical tree species. A comprehensive set of fine root traits, including morphological, physiological, and mycorrhizal characteristics, was measured to evaluate species-specific phosphorus foraging strategies. The results showed that AM species were more responsive to phosphorus form variation than ECM species, particularly under inorganic and mixed phosphorus treatments. Significant changes in root diameter (RD), root tissue density (RTD), and acid phosphatase activity (RAP) were observed in AM species, often accompanied by higher phosphorus accumulation in fine roots. For example, RD in AM species significantly decreased under the Na₃PO₄ treatment (0.94 mm) compared to the control (1.18 mm), while ECM species showed no significant changes in RD across treatments (1.12–1.18 mm, p > 0.05). RTD in AM species significantly increased under Na₃PO₄ (0.030 g/cm³) and Mixture (0.021 g/cm³) compared to the control (0.012 g/cm³, p < 0.05), whereas ECM species exhibited consistently low RTD values across treatments (0.017–0.020 g/cm³, p > 0.05). RAP in AM species increased significantly under Na₃PO₄ (1812 nmol/g/h) and Mixture (1596 nmol/g/h) relative to the control (1348 nmol/g/h), while ECM species showed limited variation (1286–1550 nmol/g/h, p > 0.05). In contrast, ECM species displayed limited trait variation across treatments, reflecting a more conservative acquisition strategy. In addition, trait correlation analysis revealed stronger coordination among root traits in AM species. And AM species exhibited high variability across treatments, while ECM species maintained consistent trait distributions with limited plasticity. These findings suggest that AM and ECM species adopt fundamentally different phosphorus acquisition strategies. AM species rely on integrated morphological and physiological responses to variable phosphorus conditions, while ECM species maintain stable trait configurations, potentially supported by fungal symbiosis. Such divergence may contribute to functional complementarity and species coexistence in phosphorus-limited subtropical forests. Full article

Dual mycorrhizal symbiosis, i.e., the association with both arbuscular and ectomycorrhizal fungal symbionts, is an ambiguous phenomenon concurrently considered as common among various genetic lineages of trees and a result of bias in data analyses. Recent studies have shown that the ability to form dual mycorrhizal associations is a distinguishing factor for the continental-scale invasion of alien tree species. However, the phylogenetic mechanisms that drive it remain unclear. In this study, all the evidence on root-associated symbionts of Juglandaceae from South and North America, Asia, and Europe was combined and re-analysed following current knowledge and modern molecular-based identification methods. The Juglandaceae family was revealed to represent a specific pattern of symbiotic interactions that are rare among deciduous trees and absent among conifers. Closely related phylogenetic lineages of trees usually share the same type of symbiosis, but Juglandaceae contains several possible ones concurrently. The hyperdiversity of root symbionts of Juglandaceae, unlike other tree families, was concurrently found in Central and North America, Asia, and Europe, indicating its phylogenetic determinants, which endured geographical isolation. However, for many Juglandaceae, including the invasive Juglans and Pterocarya species, this was never studied or was studied only with outdated methods. Further molecular research on root symbionts of Juglandaceae, providing long sequences and high taxonomic resolutions, is required to explain their ecological roles. Full article

Arbuscular mycorrhizal (AM) fungi (AMF) form a symbiotic association with terrestrial plants and increase growth and productivity. The relationships between the growth of centipedegrass (CG) and AMF are not well understood. We monitored the growth and AM colonization of CG growing on the four slopes (north, east, south, and west) of a pasture, to obtain information on aspect differences in the soil chemical properties–grass–AMF association. Soil properties almost always varied between the slope aspects. The total soil N, C, EC, and moisture tended to be highest on the northern aspect, whereas the soil available P and pH tended to be highest on the western and southern aspects, respectively. Despite the aspect differences in the microclimate and soil properties, CG grew well in all aspects, showing similar dry matter weights (DMW) for the fouraspects. Furthermore, the AM colonization of CG, in any characteristic structures (internal hyphae, vesicles, and arbuscules), was not significantly different between the slope aspects on most measurement occasions, although the colonization usually varied between the seasons and years. There were no relationships between the DMW and AM characteristic structure colonization and between the DMW and soil chemical properties. However, the colonization of the arbuscules and vesicles of the CG had a correlation with some soil chemical properties. The results suggest that AM colonization on CG growing in a hill pasture did not differ between the slope aspects. This may be a factor contributing to the high adaptability of the grass to all slope aspects. Full article

The present research focused on the physiological alterations and antioxidant potential of Portulaca oleracea L. due to mycorrhizal symbiosis with diverse strains. Purslane belongs to the plants that form a symbiosis with mycorrhizal fungi and show tolerance to various strains. Inoculation with Funneliformis mosseae gave better mycorrhizal colonization results and positively affected biomass accumulation and the concentration of reducing sugars. The total accumulation of plastid pigments was higher in symbiotic plants, although this effect was not specific to any particular strain. Mycorrhizal fungi increased the levels of carotenes in the shoots, while xanthophylls decreased, with the highest values observed in non-inoculated plants. Both strains influenced the ratio of betalains: Funneliformis mosseae promoted the accumulation of β-cyanins, while Claroideoglomus claroideum increased β-xanthines. The association with Funneliformis mosseae also affected antioxidant capacity, as indicated by the FRAP test, by altering the concentrations of secondary metabolites, particularly phenols and flavonoids. Targeted inoculation with specific strains boosts both non-enzymatic (including water-soluble and lipid-soluble metabolites) and enzymatic antioxidant activity; however, it was not dependent on the strain. These findings underscore the benefits of mycorrhizal associations in purslane cultivation, promoting sustainable ecological practices and enhancing its quality as a food product. Full article

Although many plant families are predominantly mycorrhizal, few symbiotic relationships between plants and arbuscular mycorrhizal fungi (AMF) have been thoroughly studied. Mycorrhized plants tend to exhibit greater tolerance to soil-borne pathogens and enhanced plant defence. Legumes, including common bean (Phaseolus vulgaris L.), are essential sources of protein globally. To improve common bean productivity, identifying efficient native microsymbionts is crucial. This study aimed to identify native AMF associated with common bean roots that could act as biostimulants and protect against soil diseases under varying environmental conditions. Agronomic trials were conducted at MBG-CSIC (Pontevedra, Spain) in 2021 and 2022, testing combinations of nitrogen fertilization, Burkholderia alba, Trichoderma harzianum, and a control. Traits such as nodulation, biomass, plant vigor, disease severity, nutrient content, and yield were evaluated. Four AMF species across three genera were identified. No consistent pattern was observed in AMF influence on agronomic traits. However, reduced mycorrhization in 2022 was associated with decreased nodulation, likely due to higher temperatures. Surprisingly, yields were higher in 2022 despite lower colonization. These findings suggest that intelligent use of AMF could reduce pesticide use, enhance sustainability, and promote healthier food systems. Continued research and conservation efforts are essential to optimize their benefits in legume production. Full article

Arbuscular mycorrhizal fungi (AMF) exhibit diverse strategies for colonization and survival, yet the extent to which different propagule types—roots, extraradical hyphae, and spores—contribute to these processes remains unclear. In a pot experiment using Allium tuberosum and soils from three field sites, we characterized AMF communities in root, hyphal, and spore fractions through 18S rRNA gene sequencing. A total of 427 OTUs were identified, with Glomus and Paraglomus dominating. Root fractions contained significantly more OTUs than hyphal fractions, suggesting strong specialization for intraradical colonization. Only a small subset of taxa occurred across all propagule types. Indicator species analysis revealed 21 OTUs with significant associations, mainly in root and hyphal fractions, while spore-specific taxa were rare. PERMANOVA revealed that both propagule type and soil type shaped the community structure, with propagule identity being the stronger factor. These results highlight propagule-type specialization as a key ecological trait in AMF and underscore the importance of examining multiple fungal compartments to fully capture AMF diversity and function. Full article

Blueberry growth is closely tied to its rhizosphere’s microbial communities. Recent advancements in high-throughput sequencing and multi-omics technologies have enhanced the investigation of variations in rhizosphere microbial communities and their functional roles across different plant cultivars. In this study, high-throughput sequencing was utilized to assess the rhizosphere microbial diversity in highbush and rabbiteye blueberry groups, encompassing a total of eight cultivars. Notable variations were observed in both bacterial and fungal community diversity. Ten bacterial phyla, each with a relative abundance greater than 1%, constituted 92.32–97.08% of the total abundance across the eight cultivars, with Acidobacteriota, Actinobacteriota, and Pseudomonadota being predominant. Similarly, five major fungal phyla, each exceeding 1% in relative abundance, accounted for 88.18–97.20% of the total abundance, with Ascomycota and Basidiomycota being the most dominant. The results showed that the rhizospheres of blueberries host a variety of plant growth-promoting rhizobacteria (PGPR), including genera such as Burkholderia, Enterobacter, Streptomyces, Arthrobacter, and Pseudomonas. Rabbiteye blueberry cultivars exhibit a greater propensity for accumulating beneficial symbiotic microorganisms compared to highbush cultivars. Notably, the relative abundance of ericoid mycorrhizal fungi, specifically Oidiodendron, is significantly elevated in the cultivars Emerald, Premier, O’Neal, and Brightwell, with the most pronounced increase observed in Emerald. Furthermore, rabbiteye blueberries support a more diverse and abundant array of cultivar-specific fungal communities than their highbush counterparts. Understanding the interaction networks between blueberries and their associated microbes can provide a theoretical foundation for the targeted regulation of rhizosphere microbiomes and offer valuable insights for the management of rhizospheres in other acidophilic crops. Full article

Urban green spaces are integral components of city ecosystems, supporting essential belowground microbial communities such as arbuscular mycorrhizal fungi (AMF). Understanding how green space types influence AMF communities is key to promoting urban ecological function. This study examines AMF diversity, community assembly, and co-occurrence network structures in two urban green space types—park and roadside—in Kaifeng, Henan Province, China. Soil samples were collected from both sites, and AMF community composition was assessed using high-throughput sequencing. Environmental variables, including total nitrogen (TN), available phosphorus (AP), available potassium (AK), water content, and pH, were measured to evaluate their influence on AMF communities. The results indicate marked differences between the two green space types. Park soils support significantly greater AMF species richness and more complex co-occurrence networks than roadside soils. These differences are correlated with higher nutrient levels in park soils. By contrast, AMF communities in roadside soils are more strongly associated with soil water content and pH, resulting in reduced diversity and more homogeneous community structures. Stochastic processes predominantly govern community assembly in both green space types, with roadside green spaces being more influenced by stochastic processes than park green spaces. These findings highlight the influence of urban landscape type on AMF communities and provide guidance for enhancing urban biodiversity through targeted landscape planning and soil management. In future work, we will implement long-term AMF monitoring across different green-space types and evaluate specific management practices to optimize soil health and ecosystem resilience. Full article

Understanding species-specific mechanisms governing symbiotic fungal responses to plant traits and soil factors is critical for optimizing urban tree “plant-soil-fungus” systems under pollution stress. To address this gap, we combined δ¹³C/δ¹⁵N isotope analysis and ITS sequencing for three common street trees in Beijing: Sophora japonica, Ginkgo biloba, and Populus tomentosa. In S. japonica, symbiotic fungal abundance was positively associated with leaf δ¹⁵N, indicating root exudate-mediated “plant-microbe” interactions during atmospheric NO_x assimilation. G. biloba, with weak NO_x assimilation, exhibited a negative correlation between fungal abundance and soil available N/P, suggesting mycorrhizal nutrient compensation under low fertility. P. tomentosa showed decreased fungal abundance with increasing soil N/P ratios and specific leaf area, reflecting carbon allocation trade-offs that limit mycorrhizal investment. These results demonstrate that symbiotic fungi respond to atmospheric and edaphic drivers in a tree species-dependent manner. Urban greening strategies should prioritize S. japonica for its NO_x mitigation potential and optimize fertilization for G. biloba (nutrient-sensitive fungi) and P. tomentosa (nutrient balance sensitivity). Strategic mixed planting of P. tomentosa with S. japonica could synergistically enhance ecosystem services through complementary resource acquisition patterns. This study provides mechanism-based strategies for optimizing urban tree management under atmospheric pollution stress. Full article

Modern wheat breeding has largely emphasized aboveground traits, often at the expense of belowground characteristics such as root biomass, architecture, and beneficial microbial associations. This has narrowed genetic diversity, impacting traits essential for stress resilience and efficient nutrient and water acquisition—factors expected to become increasingly critical under climate change. In this study, we evaluated 36 primary synthetic (PS) hexaploid wheat lines developed by crossing Aegilops tauschii with the durum wheat cultivar Langdon (LNG) and compared them with LNG and the hexaploid variety Norin 61 (N61). We observed significant variation in root length, biomass, and associations with fungal endophytes, including beneficial Arbuscular Mycorrhizal Fungi (AMF) and Serendipita indica, and pathogenic Alternaria sp. Clustering analysis based on these traits identified three distinct PS groups: (1) lines with greater root length and biomass, high AMF and S. indica colonization, and low Alternaria infection; (2) lines with intermediate traits; and (3) lines with reduced root traits and high Alternaria susceptibility. Notably, these phenotypic patterns corresponded closely with the soil classification of the Ae. tauschii progenitors’ origin, such as Cambisols (supportive of root growth), and Gleysols and Calcisols (restrictive of root growth). This highlights the soil microenvironment as a key determinant of belowground trait expression. By comparing PS lines with domesticated tetraploid and hexaploid wheat, we identified and selected PS lines derived from diverse Ae. tauschii with enhanced root traits. Our study emphasizes the potential of wild D-genome diversity to restore critical root traits for breeding resilient wheat. Full article

The rhizospheric microbial community plays a crucial role in the growth and ecological adaptation of truffles. Although extensive research has been conducted on bacterial communities in truffle habitats, the spatial variation and functional implications across different regions and soil compartments remain poorly understood in the current literature. In this study, soil bacterial communities were analyzed using 16S rRNA high-throughput sequencing across truffle-producing (Tuber sinense) and non-producing sites in Quercus aliena forests in Panzhihua, China. To capture microhabitat-level variation, soils were classified into three compartments: rhizosphere soil tightly adhering to ectomycorrhizal roots (TRS), rhizoplane soil loosely attached to roots (TRE), and bulk soil from truffle zones without visible roots (TBS), with corresponding controls (RS, RE, BS) collected from truffle-free forests. An alpha diversity analysis revealed that truffle-producing soils harbored significantly higher bacterial richness than control soils, while beta diversity indicated more clustered community composition in truffle-associated soils. A taxonomic analysis showed that T. sinense occurrence was associated with enrichment of specific bacterial taxa, including Chloroflexi, Anaeromyxobacteraceae, and Bradyrhizobium, whereas widespread taxa such as Firmicutes and Bacteroidota were more abundant in control soils. To further identify microbial indicators closely associated with truffle presence, we employed random forest modeling, which highlighted Pseudomonas, Streptomyces, and Bradyrhizobium as key genera distinguishing truffle-associated rhizospheres. These findings suggest that T. sinense may influence the composition of rhizospheric microbial communities, thereby constructing a favorable rhizospheric microenvironment. This work provides new insights into the microbial ecology of T. sinense and lays a foundation for future truffle domestication and cultivation efforts. Full article

In Montenegro, coniferous forests play a key ecological role in maintaining ecosystem stability. Root-associated mycorrhizal fungi and saprotrophic fungi inhabiting forest soils are well known for their roles in nutrient cycling, organic matter decomposition, and supporting host tree health. In contrast, the fungal communities residing within conifer needles, despite potentially important ecological functions, remain largely underexplored, particularly in natural and marginal forest ecosystems such as those in the Balkans. This study aimed to investigate the diversity and community composition of needle-associated fungi in three native conifers: Picea abies and Abies alba (at the edge of their native range), and the endemic Pinus heldreichii, from different mountainous regions in Montenegro. High-throughput sequencing was conducted to assess fungal diversity and community composition. Dothideomycetes dominated fungal communities in all three tree species, followed by Leotiomycetes and Tremellomycetes. Multivariate analysis revealed distinct fungal communities in P. heldreichii, whereas fungal communities in A. alba and P. abies were partially overlapping. Functional classification showed a dominance of saprotrophic, pathogenic, and endophytic fungi, with P. heldreichii exhibiting the highest proportion of saprotrophs, while A. alba and P. abies showed a considerable proportion of pathogens. The findings highlight strong host specificity, biogeographical influences, and the ecological importance of fungal communities in coniferous forests. This study provides new insights into the diversity and functional roles of needle-associated fungi, emphasizing the need for conservation efforts to maintain microbial biodiversity in native forests of Montenegro. Full article

Arbuscular mycorrhizal (AM) fungi are root symbionts that play an important role in the growth of vascular plants. Four AM fungi, including three new species, Acaulospora citrusnsis, A. guangxiensis, A. jiangxiensis, and a new country record from China, Acaulospora herrerae, are reported based on morphological characteristics and molecular phylogenetic analysis. They were isolated and propagated from spores extracted from the rhizosphere soils of citrus. A. citrusnsis is characterized by forming hyaline to pale yellow globose to subglobose spores of (70.0–)85.0(−100.0) μm in diameter. Spores of A. guangxiensis are pale yellow to pale yellowish brown, with spherical to sub-spherical appearance and (103.1–)122.1(–147.1) μm in diameter. Young spores of A. jiangxiensis are hyaline, gradually turning pale yellow as they mature, with spherical to sub-spherical appearance and (78.7–)85.6(–90.0) μm in diameter. Spores of A. herrerae are hyaline and 86.3–127.2 μm in diameter. Four species have three spore wall layers, and spores form individually in the soil. The phylogenetic tree was constructed and inferred from sequences of 18S-ITS1-5.8S-ITS2-28S datasets by Bayesian inference and maximum likelihood analysis. Voucher specimens are deposited in the Center for Subtropical Arbuscular Mycorrhizal Fungi Culture Collection (CSMC). Full article