Arbuscular Mycorrhizal Research Articles

Indigenous Arbuscular Mycorrhizal Fungi Consortium Enhances Growth and Protects Boufeggous Gharas Date Palm Against Fusarium oxysporum f. sp. albedinis Infection in Figuig Oasis (Morocco)

An indigenous consortium of arbuscular mycorrhizal fungi (AMF) from the Figuig oasis in southern Morocco, comprising Rhizophagus sp., Funneliformis sp., Acaulospora sp., Sclerocystis sp., and Scutellospora sp., was evaluated for its effects on the growth and sensitivity of Phoenix dactylifera L. variety (cv. Boufeggous Gharas) to Fusarium oxysporum f. sp. Albedinis (Foa), the causal agent of Bayoud disease. Despite its high fruit quality and local appreciation, the Boufeggous Gharas variety is highly susceptible to Foa and is currently at risk of extinction, underscoring the urgent need for its sustainable management. The results demonstrated that Boufeggous Gharas seedlings inoculated with a consortium of indigenous AMF showed significantly improved shoot and root length, leaf number, and biomass as compared to non-mycorrhized seedlings. In contrast, Foa-infected seedlings showed significantly reduced growth, with a 46.6% decrease in shoot height and a 50.4% reduction in root length compared to non-infected seedlings. Interestingly, AMF inoculation mitigated this sensitivity to Foa, significantly restoring growth parameters. Seedlings treated with AMF + Foa showed a 51% increase in shoot height and a 61% improvement in root length, along with over 100% gains in shoot and root biomass compared to seedlings infected solely with Foa. This study provides the first evidence of integrating AMF into sustainable date palm cultivation practices to mitigate the impacts of biotic stresses, thereby promoting the preservation and valorization of vulnerable date palm varieties. The protective effects of AMF are attributed to improved nutrient uptake, enhanced root architecture, and systemic resistance induced by AMF colonization.

Co-inoculation of compost with arbuscular mycorrhizal fungi and endophytic bacteria to alleviate the adverse impact of drought stress in maize

Co-inoculation of compost with arbuscular mycorrhizal fungi and endophytic bacteria to alleviate the adverse impact of drought stress in maize

Labile Carbon Input Mitigates the Negative Legacy Effects of Nitrogen Addition on Arbuscular Mycorrhizal Symbiosis in a Temperate Grassland

Nitrogen (N) deposition and carbon (C) addition significantly influence the dynamics of plant–microbe interactions, particularly altering the symbiotic relationship between plants and arbuscular mycorrhizal fungi (AMF). However, the effects and underlying mechanisms of labile C input on the relationship between AMF and various plant species in a nitrogen-enriched environment remain a knowledge gap. A seven-year field experiment was conducted to examine how six levels of N and three levels of labile C addition impact AMF colonization in four key plant species: Leymus chinensis (Trin. ex Bunge) Tzvelev, Stipa baicalensis Roshev., Thermopsis lanceolata R. Br. and Potentilla bifurca Linn. Our results showed that N and C additions exert significantly different effects on the relationship between AMF and various plant species. Labile C addition mitigated historical N negative effects, particularly for S. baicalensis, enhancing AMF infection and promoting nutrient exchange under high-N and low-C conditions. The relationship between AMF and both L. chinensis and T. lanceolata changed to weak mutualism under low-N and high-C conditions, with significant decreases in vesicular and arbuscular abundance. Plant root stoichiometry plays a critical role in modulating AMF symbiosis, particularly under high-N and -C conditions, as reflected in the increased AMF infection observed in T. lanceolata and P. bifurca. Our findings emphasize the species-specific and nutrient-dependent AMF symbiosis, revealing that targeted C input can mitigate the legacy effects of N enrichment. Effective nutrient management is of crucial importance for ecological restoration efforts in temperate grasslands affected by long-term N enrichment.

Half-Century Scientometric Analysis: Unveiling the Excellence of Fungi as Biocontrol Agents and Biofertilisers

Reducing the use of chemical inputs is becoming a major challenge in developing sustainable agriculture. Fungi, known as biocontrol agents (BCAs) and biofertilisers, are crucial in scientific research and are celebrated for their efficacy, eco-friendliness, and multifaceted roles. In this study, a bibliometric analysis was conducted on 5349 articles related to fungi as BCAs and biofertilisers over the past half-century using the Web of Science Core Collection (WoSCC) database. The publications on fungi, such as BCAs and biofertilisers, have increased significantly over the last 20 years, with a maximum growth rate of 33.7%. The USA and China lead in this field. Keyword clustering analysis revealed that entomopathogenic fungi, including Hemiptera, Coleoptera, and Lepidoptera, can be used to manage plant pests. It also showed that fungi can be used as biofertilisers to promote plant growth. The analysis of research trends shows that Beauveria bassiana in biological control is highly significant. This study also showed that entomopathogenic fungi control plant pests by infiltrating the insect cuticles. Trichoderma spp. exert biocontrol effects by producing antibiotics. Arbuscular mycorrhizal fungi can trigger plant defence mechanisms by modulating secondary metabolite synthesis. This study contributes to the current knowledge of fungi as BCAs and biofertilisers and can guide future research.

Digging deeper into the impacts of different soil water systems on the date palm root architecture and associated fungal communities

Abstract In arid regions, excessive water use threatens agricultural sustainability and overall livelihoods. It is essential to minimize water consumption to address these issues. Date palm (Phoenix dactylifera L.) is an emblematic crop of arid regions and a major water consumer. Adapting current irrigation systems to be more water-efficient systems could help cope with the water consumption of this crop. Microbial communities associated with plants are essential for agricultural sustainability and could improve the water use efficiency in regions threatened by water scarcity. These communities should thus be seriously taken into account when adapting agrosystems to the current global change setting. However, no information is presently available on the effects of the different soil water systems on date palm microbial communities. This study highlights the impact of different soil water systems (flooding and drip irrigation, natural conditions and abandoned farms) on date palm root fungal communities at different soil depths (40, 80 and 140 cm deep). The findings revealed that the soil water systems had a marked impact on fungal communities and that drip irrigation reduced the fungal diversity but increased the abundance of arbuscular mycorrhizal fungi. We showed that these effects were similar at all sampling depths. Finally, as the root architecture is a major determinant of water uptake, we reveal different behaviors of the root architecture under these different soil water systems to 160 cm depth. The findings of this study give new insights into the date palm root architecture and associated fungal communities, particularly in the context of the water availability crisis, which drives the adaptation of agricultural systems.

Isolation and molecular identification of arbuscular mycorrhizal fungi at two sites of perennial rice fields in Yunnan

Isolation and molecular identification of arbuscular mycorrhizal fungi at two sites of perennial rice fields in Yunnan

Terroir and farming practices drive arbuscular mycorrhizal fungal communities in French vineyards

BackgroundNature-based management of vineyards is at the heart of a sustainable development for the next decades. Although much is known about grapevine benefits from Arbuscular Mycorrhizal Fungi (AMF), little is known about the influence of vineyard terroir and farming practices on AMF communities.MethodsWe examined the relative effect of wine terroir and agricultural practices (organic, conversion, and conventional) on AMF abundance and diversity across 75 vineyards distributed over 14 wine terroirs in 6 winegrowing regions in France. We estimate AMF abundance by measuring spore density and root mycorrhization rates, and characterize AMF communities composition using metabarcoding by sampling both root and spore compartments for each vineyard.ResultsOrganic farming slightly increases AMF abundance (spore density and mycorrhization rate). Vineyards under conversion and using organic practices display a higher AMF diversity than conventional ones. Terroirs vary widely in terms of AMF abundance and diversity, with the median of OTUs count per sample ranging from 9 (Côte des Blancs) to 35 (Gigondas). The composition of AMF communities is structured mainly by terroir and in a lesser extent by practice. The effect of terroir on AMF communities is partially explained by distance decay and soil properties, but the majority of variation is still explained only by the terroir identity. Organic practices improve both abundance and diversity of AMF in vineyards, possibly leading to more productivity and resilience of grapevines.ConclusionThis large-scale study highlights the importance of terroir in our understanding of vineyard microbiome and paves the way to incorporation of AMF in microbial terroir studies and applications.

Effect of AM fungi on the growth and powdery mildew development of Astragalus sinicus L. under water stress.

Arbuscular mycorrhizal (AM) fungi are widely existing soil microorganisms that form symbiotic relationships with most terrestrial plants. They are important for enhancing adversity resistance, including resistance to disease and water stresses. Nevertheless, it is not clear whether the benefits can be maintained in regulating the occurrence of plant diseases under drought, flooding stress and during water restoration. In this study, we investigated the effect of AM fungus (Glomus versiforme) on the development of powdery mildew in Chinese milk vetch (Astragalus sinicus) under drought, flooding, and water recovery. The results showed that AM fungal symbiosis promoted the growth of Chinese milk vetch under water stress conditions. It increased the accumulation of ethylene (ET) and jasmonic acid (JA), enhanced the activities of antioxidant enzymes, and decreased the accumulation of salicylic acid (SA) and abscisic acid (ABA). The differentially expressed genes (DEGs) obtained from transcriptome sequencing under each stress were subjected to weighted gene co-expression network analysis (WGCNA), and a total of 12 gene co-expression modules were obtained. The analysis of the relationship between the co-expressed genes in the 12 modules and plant physiological traits showed that the magent, grey60 and darkturquoise modules were significantly associated with ET, SA, JA, ABA, plant defence enzyme activities, malondialdehyde (MDA) and H2O2 content. Water stress and disease were related with the up-regulated expression of genes in the flavonoid biosynthesis and oxidative phosphorylation, plant hormone signal transduction and plant-pathogen interaction pathways. Importantly, inoculation with AM fungus reduced the incidence of powdery mildew under drought stress by 16.54%. In summary, the results of this study showed that inoculation with AM had a positive effect on powdery mildew development tolerance in Chinese milk vetch under drought and flooding stresses and stress recovery. This provides a good basis for field management and sustainable growth of green manure crop Chinese milk vetch.

NO3--N pulse supply caused by biodegradable plastics exacerbates Trifolium repens L. invasion.

The exacerbation of plant invasion by microplastics attracted widespread attention. Pulse resource hypothesis is popular theory to elucidate plant invasion. Our previous work demonstrated biodegradable microplastics (BMPs) could increase the arbuscular mycorrhizal fungi (AMF) colonization rate. Reportedly, AMF can enhance rhizobia colonization. Therefore, we infer the coexistence of BMPs with legumes may lead to an increased colonization of rhizobia with negative feedback regulation of N fixation. This could result in NO3--N pulse supply, thereby exacerbating plant invasion. Subsequently, a 60-day pot experiment was conducted using Trifolium repens L. as invasive plant and Oxalis corniculata L. as native plant, with 1% or 5% wt BMPs. AMF colonization, BMPs degradation, NO3--N content and pulse supply, rhizobia colonization, relative competitive intensity, replacement diagrams and NO3--N utilization were determined. The mechanism was clarified through heat map and structural equation model. The results reveal the greater the NO3--N consumption by BMPs, the more AMF promoted rhizobia colonization in T. repens, thereby the larger the pulse amplitude of NO3--N supply, then, the higher the NO3--N utilization rate of T. repens. It exacerbates T. repens invasion. This study clarifies effects of BMPs on rhizobia's N fixation, and enriches the evidence on mechanism of BMPs exacerbating plant invasion.

Arbuscular mycorrhizal fungi enhance drought resistance and alter microbial communities in maize rhizosphere soil

Although the benefits of inoculation with arbuscular mycorrhizal fungi (AMF) for mitigating drought stress and enhancing plant growth of host are well‐studied, our understanding of their interactions with soil attributes and rhizosphere microbial communities remains limited. In the present study, we conducted a pot experiment to explore how AMF affects maize growth, antioxidant activity, soil properties, and the rhizosphere microbial communities under drought stress. The results showed that AMF inoculation during drought stress resulted in improved maize seedling growth, significantly increasing plant biomass (42.7%), chlorophyll content (13.4%), and antioxidant capacity. It also enhanced soil nutrient availability and microbial biomass. We observed significant shifts in the structure and composition of the rhizosphere microbial community with AMF inoculation under drought conditions when compared to those under well-watered conditions. Significantly, bacterial diversity and composition showed greater sensitivity to drought stress than fungal communities. This was attributed to plants preferentially reducing the supply of carbon sources to bacterial rather than to fungal communities under drought conditions. AMF inoculation also enhanced the complexity (e.g., degree) and stability of the rhizosphere microbial ecological network, suggesting closer ecological interactions within the soil microbial community. Furthermore, bacterial diversity and richness played a more important role in soil function than those of fungal communities under drought stress, particularly with AMF inoculation. Overall, our findings suggest that AMF inoculation alters soil microbial diversity and interactions, highlighting their key roles in enhancing plant stress tolerance and mitigating the negative effects of drought on agricultural ecosystems.

Field inoculation with a local arbuscular mycorrhizal (AM) fungal consortium promotes sunflower agronomic traits without changing the composition of AM fungi coexisting inside the crop roots

Field inoculation with a local arbuscular mycorrhizal (AM) fungal consortium promotes sunflower agronomic traits without changing the composition of AM fungi coexisting inside the crop roots

Plant-microbiome interactions for enhanced crop production under cadmium stress: A review.

Cadmium (Cd) is a toxic heavy metal that has detrimental effects on agriculture crops and human health. Both natural and anthropogenic processes release Cd into the environment, elevating its contents in soils. Under Cd stress, strong plant-microbiome interactions are important in improving crop production, but a systematic review is still missing. This review demonstrates the importance of microbiomes and their interactions with plants in mitigating Cd toxicity and promoting crop growth. Endogenous and exogenous microbiomes play a role to enhance plant's ability to respond to Cd stress. Specifically, the rhizosphere microbiome, which includes plant growth-promoting rhizobacteria and arbuscular mycorrhizal fungi, endosphere microbiome, and phyllosphere microbiome, are involved in Cd accumulation, immobilization, and translocation, and Cd-induced stress management. The mechanisms underlying these plant-microbiome interactions vary depending on the species and varieties of crops, composition and diversity of the microbiome, and level of Cd stress. Among the microbiome-mediated approaches, biosorption, bioprecipitation, and bioaccumulation are promising for Cd remediation in soil. Additionally, the endosphere microbiome, particularly Cd resistant endophytes, reduces Cd toxicity, increases the expression of Cd efflux genes, and enhances crop growth through regulating crops' antioxidant machinery and endogenous hormones. Furthermore, improved agricultural practices modulate the soil and plant microbiomes, thereby reducing Cd stress and increasing crop productivity.

Interactions of silicon and arbuscular mycorrhizal fungi on phosphorus uptake during rice vegetative growth

Interactions of silicon and arbuscular mycorrhizal fungi on phosphorus uptake during rice vegetative growth

Common mycorrhizal networks improve survival and mediate facilitative plant interactions among Andropogon gerardii seedlings under drought stress

Under drought conditions, arbuscular mycorrhizal (AM) fungi may improve plant performance by facilitating the movement of water through extensive hyphal networks. When these networks interconnect neighboring plants in common mycorrhizal networks (CMNs), CMNs are likely to partition water among many individuals. The consequences of CMN-mediated water movement for plant interactions, however, are largely unknown. We set out to examine CMN-mediated interactions among Andropogon gerardii seedlings in a target-plant pot experiment, with watering (watered or long-term drought) and CMN status (intact or severed) as treatments. Intact CMNs improved the survival of seedlings under drought stress and mediated positive, facilitative plant interactions in both watering treatments. Watering increased mycorrhizal colonization rates and improved P uptake, particularly for large individuals. Under drought conditions, improved access to water most likely benefited neighboring plants interacting across CMNs. CMNs appear to have provided the most limiting resource within each treatment, whether P, water, or both, thereby improving survival and growth. Neighbors near large, photosynthate-fixing target plants likely benefited from their establishment of extensive hyphal networks that could access water and dissolved P within soil micropores. In plant communities, CMNs may be vital during drought, which is expected to increase in frequency, intensity, and length with climate change.

Enhancement of alfalfa growth resistance by arbuscular mycorrhiza and earthworm in molybdenum-contaminated soils: From the perspective of soil nutrient turnover.

Molybdenum (Mo) acts as a crucial nutrient for plant development, yet excessive soil exposure can cause detrimental effects. Molybdenosis symptoms remain subtle in many plants, largely due to the safeguarding functions of soil organisms, the fundamental biological mechanisms lack clarity. In this study, we explored the potential mechanisms for amending Mo-exposed soils with soil microbe-arbuscular mycorrhizal fungi (AMF) and soil fauna, specifically earthworms, to enhance model plant-alfalfa growth resistance through soil nutrient turnover perspectives. Our findings illustrated that excessive Mo exposure disrupted soil nutrient turnover, manifesting as exacerbated microbial C and N metabolic limitations. Consequently, this interference intensified nutrient competition between alfalfa and soil microbes, thereby impeding alfalfa nutrient uptake and growth resistance. The synergistic application of AMF and earthworms alleviated microbial C (8.55% ∼ 28.23%) and N (11.14% ∼ 37.55%) metabolic limitations by modulating soil enzyme activities, particularly P-acquiring enzyme. This co-approach facilitated enhanced C and N accumulation in alfalfa, thus improving its growth resistance (24.15% ∼ 123.74%) under Mo exposure. Furthermore, in contrast to singular treatments, the combination of AMF and earthworms bolstered mutual Mo tolerance, amplifying biological benefits for alfalfa growth. Earthworms promoted AMF colonization and the secretion of glomalin-related soil proteins (GRSP), while AMF alleviated Mo accumulation and oxidative stress in earthworms. Additionally, the AMF-induced regulation of gut metabolism reduced earthworm mortality and minimized weight loss. Our study underscores the necessity of maintaining soil biodiversity when utilizing Mo fertilizers to mitigate the potential risks of Mo over-exposure affecting soil nutrient turnover and plant growth.

Response of root- and soil-associated AM fungi to nitrogen addition and simulated drought in a Chinese fir plantation

Response of root- and soil-associated AM fungi to nitrogen addition and simulated drought in a Chinese fir plantation

Higher temperatures decreased the abundance of arbuscular mycorrhizal fungi and the complexity of their networks by reducing tree diversity

Higher temperatures decreased the abundance of arbuscular mycorrhizal fungi and the complexity of their networks by reducing tree diversity

Metabolomics analysis reveals crucial effects of arbuscular mycorrhizal fungi on the metabolism of quality compounds in shoots and roots of Camellia sinensis L

Metabolomics analysis reveals crucial effects of arbuscular mycorrhizal fungi on the metabolism of quality compounds in shoots and roots of Camellia sinensis L

Synergistic effect of arbuscular mycorrhizal fungi, biochar and seaweed extract for improving the copper tolerance in hemp

Synergistic effect of arbuscular mycorrhizal fungi, biochar and seaweed extract for improving the copper tolerance in hemp

Nurturing with nature: the efficacy of arbuscular mycorrhizal fungi microbe for cocoa sector environmental management

Despite the proven effectiveness of fertility-promoting microbes such as Arbuscular Mycorrhizal fungi (AMF) to minimize the adverse effects of environmental deterioration and climate change, there is limited understanding on its efficacy to improve cocoa resilience. Cocoa mortality (70%) caused by climate change induced drought within two years of transplanting to the field is a major constrain to farmers’ productivity. This study assessed the effect of AMF and Potassium (K) nutrition on the biochemical characteristics of cocoa and its field survival from 2019 to 2022. A split-plot factorial design was used. The treatments were cocoa varieties (CRG8914 × PA150 [V1], AMAZ15-15 × EQX78 [V2], PA150 × CRG 0314 [V3]), potassium (0 g, 2 g, 4 g plant−1), AMF (AMF, Non-AMF) and watering regimes (water-stressed and supplementary irrigation). Soil samples (0–20 cm) from cocoa rhizosphere were examined for native AMF spores and structures using the Wet Sieving and Decantation methodology and Sucrose Centrifugation. The AMF inoculum was prepared using the trap-culture technique. Under drought conditions, V1, V2 and V3 without K had leaf chlorophyll of 19.4 μmol/m2, 20.5 μmol/m2, 19.9 μmol/m2 respectively, but with 2 g KxAMF, chlorophyll increased to 21.6 μmol/m2, 26.4 μmol/m2, 26.8 μmol/m2 respectively. Phosphorus uptake and relative water content had similar pattern. Rhizophagus irregularis was morphologically identified as the AMF in soils under the cocoa trees. Multivariate Adaptive Regression Splines predicted leaf chlorophyll and phosphorus uptake as the key factor influencing cocoa survival and resilience. Considering the threat of drought caused by climate change on cocoa production in West Africa, the results have implications for farmers livelihood, cocoa survival and the sustainability of cocoa soils.