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This article is a Commentary on Giovannetti et al., 241: 1393–1400. [ABSTRACT FROM AUTHOR]

Summary: Arbuscular mycorrhizal fungi (AMF) transport substantial plant carbon (C) that serves as a substrate for soil organisms, a precursor of soil organic matter (SOM), and a driver of soil microbial dynamics. Using two‐chamber microcosms where an air gap isolated AMF from roots, we 13CO2‐labeled Avena barbata for 6 wk and measured the C Rhizophagus intraradices transferred to SOM and hyphosphere microorganisms.NanoSIMS imaging revealed hyphae and roots had similar 13C enrichment. SOM density fractionation, 13C NMR, and IRMS showed AMF transferred 0.77 mg C g−1 of soil (increasing total C by 2% relative to non‐mycorrhizal controls); 33% was found in occluded or mineral‐associated pools.In the AMF hyphosphere, there was no overall change in community diversity but 36 bacterial ASVs significantly changed in relative abundance. With stable isotope probing (SIP)‐enabled shotgun sequencing, we found taxa from the Solibacterales, Sphingobacteriales, Myxococcales, and Nitrososphaerales (ammonium oxidizing archaea) were highly enriched in AMF‐imported 13C (> 20 atom%). Mapping sequences from 13C‐SIP metagenomes to total ASVs showed at least 92 bacteria and archaea were significantly 13C‐enriched.Our results illustrate the quantitative and ecological impact of hyphal C transport on the formation of potentially protective SOM pools and microbial roles in the AMF hyphosphere soil food web. [ABSTRACT FROM AUTHOR]

Summary: 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. [ABSTRACT FROM AUTHOR]

Summary: Arbuscular (AM) and orchid (OrM) mycorrhiza are the most widespread mycorrhizal symbioses among flowering plants, formed by distinct fungal and plant species. They are both endosymbioses because the fungal hyphae can enter inside the plant cell to develop intracellular fungal structures that are surrounded by the plant membrane. The symbiotic plant–fungus interface is considered to be the major site of nutrient transfer to the host plant. We summarize recent data on nutrient transfer in OrM and compare the development and function of the arbuscules formed in AM and the pelotons formed in OrM in order to outline differences and conserved traits. We further describe the unexpected similarities in the form and function of the intracellular mycorrhizal fungal structures observed in orchids and in the roots of mycoheterotrophic plants forming AM. We speculate that these similarities may be the result of convergent evolution of mycorrhizal types in mycoheterotrophic plants and highlight knowledge gaps and new research directions to explore this scenario. [ABSTRACT FROM AUTHOR]

Summary: Rhizophagus irregularis is the model species for arbuscular mycorrhizal fungi (AMF) research and the most widely propagated species for commercial plant biostimulants.Using asymbiotic and symbiotic cultivation systems initiated from single spores, advanced microscopy, Sanger sequencing of the glomalin gene, and PacBio sequencing of the partial 45S rRNA gene, we show that four strains of R. irregularis produce spores of two distinct morphotypes, one corresponding to the morphotype described in the R. irregularis protologue and the other having the phenotype of R. fasciculatus.The two spore morphs are easily distinguished by spore colour, thickness of the subtending hypha, thickness of the second wall layer, lamination of the innermost layer, and the dextrinoid reaction of the two outer spore wall layers to Melzer's reagent. The glomalin gene of the two spore morphs is identical and that of the PacBio sequences of the partial SSU‐ITS‐LSU region (2780 bp) obtained from single spores of the R. cf fasciculatus morphotype has a median pairwise similarity of 99.8% (SD = 0.005%) to the rDNA ribotypes of R. irregularis DAOM 197198.Based on these results, we conclude that the model AMF species R. irregularis is dimorphic, which has caused taxonomic confusion in culture collections and possibly in AMF research. [ABSTRACT FROM AUTHOR]

The use of mycorrhiza and seaweed are becoming significant and complementary applications in different production systems because organisms increased quality of seedlings and crop yield. This study has been conducted under growth chamber conditions to determine some of the seedling growth parameters (length (cm), stem diameter (mm), fresh weight (g plant −1), dry weight (g plant −1), root fresh weight (g plant −1), root dry weight (g plant −1), leaf area (cm2 plant−1), SPAD, photosynthesis rate (%) and color parameters). As a plant material, Cuma F1 and Mert F1 genotype seeds were sown. Endo Roots Soluble (Mycorrhiza (ERS)) and MC-Extra (Seaweed) were applied in different doses (0, 250 and 500 mg kg−1) to seedling growing vessels at a rate of 10 ml per plant. Treatment effects in tomato were found statistically significant (p ≤.01**) on stem diameter, fresh weight, dry weight. Seedling length, leaf area and SPAD results were also statistically significant (p ≤.01**), and the results of these parameters were higher in ERS. ERS increases the leaf area and SPAD measurements in tomato seedlings. The results of pepper measurements were found to be statistically significant at p ≤.05* on root fresh weight, SPAD and photosynthesis rate. The highest values of root fresh weight, SPAD were obtained from 250 mg kg−1 doses of ERS; the highest value of photosynthesis rate was measured from 500 mg kg−1 doses of ERS on pepper. The effect of 500 mg kg−1 ERS on seedling growth was found statistically significant in pepper. [ABSTRACT FROM AUTHOR]

The hydrological regime is considered to be the major factor that affects the distribution of arbuscular mycorrhiza (AM) fungi in wetlands. We aimed to investigate the responses of AM fungal community to different hydrological gradients. Illumina Miseq sequencing technology was used to study the AM fungal community structure in roots and rhizosphere soils of Phragmites australis in different moisture areas (dry area, alternating wet and dry area, and flooded area) in Mengjin Yellow River wetland. The rhizosphere soils and roots hosted different AM fungal communities. In roots, the AM fungal colonization and Chao1 richness in dry area were significantly higher than that in alternating wet and dry area and flooded area, but the community composition did not vary clearly under different water conditions. In rhizosphere soils, the Chao1 richness of AM fungi in flooded area was significantly higher than that in alternating wet and dry area and dry area, and the AM fungal community structure obviously differed across different areas. The redundancy analyses indicated that changes in the AM fungal community in soils were associated with altered soil properties, and the abundance of the dominant genus Glomus was mostly positively correlated with alkali‐hydrolyzable nitrogen in soils. This study helps us to understand the responses of AM fungal community to hydrological gradients in wetlands. [ABSTRACT FROM AUTHOR]

Arbuscular mycorrhizal (AM) fungi frequently colonise plant roots and can affect plant morphology and physiology through their contribution to plant nutrition. However, the functional role of AM fungi in the presence of other microbial symbionts, including widespread Mucoromycotina 'fine root endophytes' (MFRE) fungi, remains largely unknown.While both AM fungi and MFRE transfer nutrients, including nitrogen, from inorganic and organic sources to host plants, their combined effects on co‐colonised plants have only been investigated in liverworts. Here, we compare the morphology and physiology of the grass Holcus lanatus grown with an AM fungal community versus a more diverse symbiotic fungal community containing both AM fungi and MFRE.Holcus lanatus plants were grown in the presence of either a diverse MFRE+AM fungi soil inoculum or a multi‐species AM fungal inoculum. Plant traits associated with growth were quantified, along with fungal transfer of 15N tracer to plants from a variety of sources (ammonium chloride, alanine, glycine and algal necromass).Holcus lanatus grown with the AM fungal community had greater root and shoot growth during early development and prior to the addition of 15N‐labelled sources, compared with plants grown with the more diverse symbiotic fungal community. When nitrogen sources were made available to the fungal symbionts in the pot microcosms, plants growing with the MFRE+AM fungi soil inoculum had a faster growth rate than plants growing with the AM fungal community. At harvest, H. lanatus grown with the AM fungal community had a larger biomass, and there were no differences in 15N tracer assimilation in plants across the two fungal community treatments.Our results demonstrate that the diversity of fungal inocula in conjunction with soil nutrient availability determine the benefits derived by plants from diverse fungal symbionts. Our research contributes to understanding host plant outcomes in diverse multi‐symbiont scenarios. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Ferns are known to have a lower incidence of mycorrhization than angiosperms. It has been suggested that this results from carbon being more limiting to fern growth than nutrient availability, but this assertion has not been tested yet. In the present study, we took advantage of a fertilization experiment with nitrogen and phosphorus on cloud forest plots of the Ecuadorean Andes for 15 years. A previous analysis revealed changes in the abundances of fern species in the fertilized plots compared to the control plots and hypothesized that this might be related to the responses of the mycorrhizal relationships to nutrient availability. We revisited the plots to assess the root‐associated fungal communities of two epiphytic and two terrestrial fern species that showed shifts in abundance. We sampled and analyzed the roots of 125 individuals following a metabarcoding approach. We recovered 1382 fungal ASVs, with a dominance of members of Tremellales (Basidiomycota) and Heliotales (Ascomycota). The fungal diversity was highly partitioned with little overlap between individuals. We found marked differences between terrestrial and epiphytic species, with the latter fundamentally missing arbuscular mycorrhizal fungi (AMF). We found no effect of fertilization on the diversity or relative abundance of the fungal assemblages. Still, we observed a direct impact of phosphorus fertilization on its concentration in the fern leaves. We conclude that fern–fungi relationships in the study site are not restricted by nutrient availability and suggest the existence of little specificity on the fungal partners relative to the host fern species. [ABSTRACT FROM AUTHOR]

Due to the increasing presence of industrial hemp (Cannabis sativa L.) and its multiple possibilities of use, the influence of different light and several biopreparations based on beneficial fungi and bacteria on hemp's morphological and physiological properties were examined. Different biopreparations and their combinations were inoculated on hemp seed and/or substrate and grown under blue and white light. A completely randomized block design was conducted in four replications within 30 days. For biopreparation treatment, vesicular arbuscular mycorrhiza (VAM) in combination with Azotobacter chroococum and Trichoderma spp. were inoculated only on seed or both on seed and in the substrate. Generally, the highest morphological parameters (stem, root and plant length) were recorded on plants in white light and on treatment with applied Trichoderma spp., both on seed and substrate. Blue light negatively affected biopreparation treatments, resulting in lower values of all morphological parameters compared to control. Leaves pigments were higher under blue light, as compared to the white light. At the same time, 1-diphenyl-2-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), flavonoids, total flavanol content and phenolic acids were not influenced by light type. Biopreparation treatments did not significantly influence the leaves' pigments content (Chl a, Chl b and Car), nor the phenolic and flavanol content. [ABSTRACT FROM AUTHOR]

In the quest for sustainable agricultural practices, there arises an urgent need for alternative solutions to mineral fertilizers and pesticides, aiming to diminish the environmental footprint of farming. Arbuscular mycorrhizal fungi (AMF) emerge as a promising avenue, bestowing plants with heightened nutrient absorption capabilities while alleviating plant stress. Cereal and oilseed crops benefit from this association in a number of ways, including improved growth fitness, nutrient uptake, and tolerance to environmental stresses. Understanding the molecular mechanisms shaping the impact of AMF on these crops offers encouraging prospects for a more efficient use of these beneficial microorganisms to mitigate climate change-related stressors on plant functioning and productivity. An increased number of studies highlighted the boosting effect of AMF on grain and oil crops' tolerance to (a)biotic stresses while limited ones investigated the molecular aspects orchestrating the different involved mechanisms. This review gives an extensive overview of the different strategies initiated by mycorrhizal cereal and oilseed plants to manage the deleterious effects of environmental stress. We also discuss the molecular drivers and mechanistic concepts to unveil the molecular machinery triggered by AMF to alleviate the tolerance of these crops to stressors. [ABSTRACT FROM AUTHOR]

Saline–alkali stress seriously endangers the normal growth of cotton (Gossypium hirsutum). Arbuscular mycorrhizal fungi (AMF) could enhance salt tolerance by establishing symbiotic relationships with plants. Based on it, a pot experiment was conducted to simulate a salt environment in which cotton was inoculated with Paraglomus occultum to explore its effects on the saline–alkali tolerance of cotton. Our results showed that salt stress noticeably decreased cotton seedling growth parameters (such as plant height, number of leaves, dry weight, root system architecture, etc.), while AMF exhibited a remarkable effect on promoting growth. It was noteworthy that AMF significantly mitigated the inhibitory effect of salt on cotton seedlings. However, AMF colonization in root and soil hyphal length were collectively descended via salt stress. With regard to osmotic regulating substances, Pro and MDA values in roots were significantly increased when seedlings were exposed to salt stress, while AMF only partially mitigated these reactions. Salt stress increased ROS levels in the roots of cotton seedlings and enhanced antioxidant enzyme activity (SOD, POD, and CAT), while AMF mitigated the increases in ROS levels but further strengthened antioxidant enzyme activity. AMF inoculation increased the photosynthesis parameters of cotton seedling leaves to varying degrees, while salt stress decreased them dramatically. When inoculated with AMF under a salt stress environment, only partial mitigation of these photosynthesis values was observed. Under saline–alkali stress, AMF improved the leaf fluorescence parameters (φPSII, Fv′/Fm′, and qP) of cotton seedlings, leaf chlorophyll levels, and root endogenous hormones (IAA and BR); promoted the absorption of water; and maintained nitrogen balance, thus alleviating the damage from salt stress on the growth of cotton plants to some extent. In summary, mycorrhizal cotton seedlings may exhibit mechanisms involving root system architecture, the antioxidant system, photosynthesis, leaf fluorescence, endogenous hormones, water content, and nitrogen balance that increase their resistance to saline–alkali environments. This study provide a theoretical basis for further exploring the application of AMF to enhance the salt tolerance of cotton. [ABSTRACT FROM AUTHOR]

To investigate the effect of soil additives in reducing the effect of water deficit stress on sugar beet, an experiment was performed as a combined analysis in two regions based on randomized complete block design with four replications. Experimental treatments were location factor at two levels of Miandoab and Malekan, water deficit stress factor at three levels of 50 mm (lack of stress), 110 mm (moderate stress) and 170 mm (severe stress) evaporation from class A evaporation pan and soil additive factor at four levels of control (no soil additives), superabsorbent, mycorrhiza and livestock manure. In the present study, the use of soil additive treatments in both regions were able to improve the yield of pure sugar compared to control. In irrigation treatment after 170 mm of evaporation, the highest leaf area index (3.28), relative leaf water content (65.96%), shoot dry weight (3.45 t ha-1 ), root yield (49.48 t ha-1 ), gross sugar yield (9.73 t ha-1 ) and pure sugar yield (8.32 t ha-1 ) were obtained by mycorrhiza application and sugar content (20.48%) and pure sugar percent (17.11%) were obtained in control and superabsorbent application, respectively. In water deficit stress, application of mycorrhiza and superabsorbent were able to significantly increase the yield of pure sugar compared to the control. Due to the fact that sugar beet is exposed to different periods of water deficit stress in the tested areas, the use of mycorrhiza and superabsorbent can be a suitable method to reduce the effect of water deficit stress in sugar beet. [ABSTRACT FROM AUTHOR]

Meeting the ever-increasing food demands of a growing global population while ensuring resource and environmental sustainability presents significant challenges for agriculture worldwide. Arbuscular mycorrhizal symbiosis (AMS) has emerged as a potential solution by increasing the surface area of a plant's root system and enhancing the absorption of phosphorus, nitrogen nutrients, and water. Consequently, there is a longstanding hypothesis that rice varieties exhibiting more efficient AMS could yield higher outputs at reduced input costs, paving the way for the development of Green Super Rice (GSR). Our prior research study identified a variant, OsCERK1DY, derived from Dongxiang wild-type rice, which notably enhanced AMS efficiency in the rice cultivar "ZZ35." This variant represents a promising gene for enhancing yield and nutrient use efficiency in rice breeding. In this study, we conducted a comparative analysis of biomass, crop growth characteristics, yield attributes, and nutrient absorption at varying soil nitrogen levels in the rice cultivar "ZZ35" and its chromosome single-segment substitution line, "GJDN1." In the field, GJDN1 exhibited a higher AM colonization level in its roots compared with ZZ35. Notably, GJDN1 displayed significantly higher effective panicle numbers and seed-setting rates than ZZ35. Moreover, the yield of GJDN1 with 75% nitrogen was 14.27% greater than the maximum yield achieved using ZZ35. At equivalent nitrogen levels, GJDN1 consistently outperformed ZZ35 in chlorophyll (Chl) content, dry matter accumulation, major nutrient element accumulation, N agronomic efficiency (NAE), N recovery efficiency (NRE), and N partial factor productivity (NPFP). The performance of OsCERK1DY overexpression lines corroborated these findings. These results support a model wherein the heightened level of AMS mediated by OsCERK1DY contributes to increased nitrogen, phosphorus, and potassium accumulation. This enhancement in nutrient utilization promotes higher fertilizer efficiency, dry matter accumulation, and ultimately, rice yield. Consequently, the OsCERK1DY gene emerges as a robust candidate for improving yield, reducing fertilizer usage, and facilitating a transition towards greener, lower-carbon agriculture. [ABSTRACT FROM AUTHOR]

In this study, the effect of mycorrhiza (Glomus intraradices N.C. Schenck & G.S. Sm.) inoculation on the micronutrient and macroelement uptakes in different organs of daffodil (Narcissus tazetta L.) grown under saline conditions is examined. For this purpose, Narcissus tazetta plant grown in the climate chamber was treated with sodium chloride (NaCl) at three different concentrations such as salt-free (S0), 34 mmol (S1) and 68 mmol (S2) in mediums with mycorrhiza (M+) and without mycorrhiza (M-). At the end of the experiment, the uptakes of sodium (Na), iron (Fe), manganese (Mn), zinc (Zn) and copper (Cu) uptakes in the bulb, root and leaves of the plant were analyzed. The effects of salt and mycorrhiza interactions on the N uptakes were statistically significant at the 5% level in bulbs. The effects of salt applications were found significant at 1% level for all nutrients uptakes of roots except Cu uptake (5%). The effects of interactions among salt and mycorrhiza were found significant at 5% level for P, Ca and Mn uptakes and at 1% level for Mg, Fe and Cu uptakes of leaves statistically. Increasing doses of sodium chloride had statistically negative effects on nutrient uptakes of different organs except Na and K uptakes of bulbs. Mycorrhiza applications generally increased nutrient uptakes of daffodil's roots and leaves under salinity conditions. The interactions between salt and mycorrhiza were significant for N in bulbs, for N, P and Fe in roots and for P, Ca, Mg, Fe, Mn and Cu in leaves. The decreases in these nutrients uptakes by 68 mmol NaCl applications were lower in mycorrhiza applications than those in non mycorrhiza applications. [ABSTRACT FROM AUTHOR]

To evaluate the effect of using mycorrhizae and rhizobium at different levels of nitrogen starter fertilizer on some important growth indices of a common bean cultivar, a factorial experiment was conducted in a randomized complete block design with three replications in 2016 at Bu-Ali Sina University research farm. The factors included two bio-fertilizers of mycorrhizae (Glomus mosseae) and rhizobium (Rhizobium phaseoli) each one with two levels (used and non-used) and nitrogen starter fertilizer with three levels (0, 30, 60 kg ha−1) from urea as the third factor. The studied factors caused significant changes in growth indices. The maximums of leaf area index (5.9), total dry weight (860 g m−2) and crop growth rate (44 g m−2 day−1) were observed in the simultaneous application of both bio-fertilizers plus use of 60 kg ha−1 N. This superior treatment compared with no bio-fertilizer + 60 kg ha−1 N treatment increased maximums of LAI, TDM and CGR, 115, 68 and 60%, respectively. Also in superior treatment, the two indices of net assimilation rate (NAR) and relative growth rate (RGR) on 60th day after planting were 25 g m−2 day−1 and 0.046 g g−1day−1, that were respectively 116 and 17% higher than no bio-fertilizer + 60 kg ha−1 N treatment. Therefore application of mycorrhiza and rhizobium simultaneously in addition to 60 kg ha−1 N as starter fertilizer is an appropriate treatment in common bean to maximize the growth indices. [ABSTRACT FROM AUTHOR]

Heavy metals like cadmium (Cd), mercury (Hg), bismuth (Bi), and arsenic (As) are potent and harmful poisonous sources that cause havoc on health conditions for the population of the world. However, the response of our crop species to these potent heavy metalsrelated toxicity is still left to be fully understood. It is a matter of great concern, as we are heavily dependent on crop species like rice, wheat, peas, etc. Our study here aims to learn about the defensive mechanism of Pisum sativum L. aided with putrescine and mycorrhiza against the stress created by Cd-related toxicity. We quantified physiological parameters such as the membrane-related injury and stability index. We further measured the total free proline content, lipid peroxidation content, and SOD activity. We executed our quantitative experiments on the stressed pea plants due to the exogenously applied Cd-toxicity in the presence and absence of mycorrhiza and putrescine. Insights of our significant results will improve the understanding of readers of the role of mycorrhiza and putrescine in improvising the tolerance level of a pea plant over Cd-related toxicity. [ABSTRACT FROM AUTHOR]

Soil biotic and abiotic factors can affect the interaction between invasive and native species. However, it is not yet clear how arbuscular mycorrhizal (AM) symbiosis affects the interaction between adult invasive plants and neighboring seedlings. We used an invasive weed (Bidens frondosa) to test the hypothesis that adult invasive plants facilitate the growth of neighboring seedlings through AM symbiosis, and this facilitation can be inhibited by the biological stress of root‐knot nematode infection. The results showed that the height and total biomass of seedlings near the adult plant increased, indicating that the belowground effects mediated by AM symbiosis played a facilitative role. The positive growth response to resource allocation between adult plant and neighboring seedlings through mycorrhizal connection was inhibited when adult plants were infected by root‐knot nematode. Only the total biomass and root–shoot ratio of adult plants were increased, while seedling growth performance did not change. Our results supported the hypothesis that adult invasive plants can facilitate their neighboring seedlings growth through AM symbiosis and the benefits vary with biotic stress on adult plant. These findings provided important evidence to explain the role of AM symbiosis in plant invasion. [ABSTRACT FROM AUTHOR]

This study aims to evaluate whether a selected arbuscular mycorrhizal fungus, Diversispora spurca, improves growth in drought-stressed walnut (Juglans regia L. cv. Qingxiang) plants and whether this improvement is associated with changes in osmolyte (fructose, glucose, sucrose, soluble protein, proline, and betaine) levels. After 60 days of soil drought treatment (50% of maximum field water-holding capacity), root D. spurca colonization rate and soil mycelium length decreased by 13.57% and 64.03%, respectively. Soil drought also inhibited the growth performance of aboveground (stem diameter, leaf number, leaf biomass, and stem biomass) and underground (root projected area, surface area, and average diameter) parts, with uninoculated plants showing a stronger inhibition than D. spurca-inoculated plants. D. spurca significantly increased these growth variables, along with aboveground part variables and root areas being more prominent under drought stress versus non-stress conditions. Although drought treatment suppressed the chlorophyll index and nitrogen balance index in leaves, mycorrhizal inoculation significantly increased these indices. Walnut plants were able to actively increase leaf fructose, glucose, sucrose, betaine, and proline levels under such drought stress. Inoculation of D. spurca also significantly increased leaf fructose, glucose, sucrose, betaine, proline, and soluble protein levels under drought stress and non-stress, with the increasing trend in betaine and soluble protein being higher under drought stress versus non-stress. Drought stress dramatically raised leaf hydrogen peroxide (H2O2) levels in both inoculated and uninoculated plants, while mycorrhizal plants presented significantly lower H2O2 levels, with the decreasing trend higher under drought stress versus non-stress. In conclusion, D. spurca symbiosis can increase the growth of drought-stressed walnut plants, associated with increased osmolyte levels and decreased H2O2 levels. [ABSTRACT FROM AUTHOR]

This field experiment aimed to assess the effects of algal biostimulants (NPK + TE) and mycorrhiza on the vegetative and productive parameters of a blueberry orchard, as well as the shelf life of fruits at three different stages of harvest. Kosovo benefits from favorable agro-climatic conditions that support high-quality agricultural production. In response to the impact of climate change, the blueberry industry in Kosovo has increasingly adopted Algae biostimulants (NPK + TE) to adapt to changing climate conditions, enhance yields, and improve blueberry resilience against environmental stressors. The experiment was conducted in the Vushtria region on a 6-hectare blueberry orchard using a nested experimental design. The plants were planted at a distance of 1×3 meters, with a density of 3333 plants per hectare in 35-liter pots. The irrigation system used is spaghetti-shaped (4 spaghetti per pot), and the orchard is covered with an anti-hail system. ANOVA analysis revealed significant differences in the number of flowers, number of open flowers, leaf surface, number of fruit, total yield, and canopy volume. The obtained results indicate that the use of mycorrhiza positively affected the number of flowers, number of open flowers, and number of leaves, ultimately increasing yield and canopy volume compared to the use of algal biostimulants (NPK + TE). Additionally, treatment with chitosan at the beginning of the harvest extended the shelf life of fruits to 25 days, significantly longer than fruits treated with algal biostimulants (20 days) and in the control six days. [ABSTRACT FROM AUTHOR]

This article explores the recruitment of arbuscular mycorrhizal (AM) conserved genes for ectomycorrhizal (ECM) symbiosis. ECM symbiosis, which is a more recent form of symbiosis than AM symbiosis, involves the formation of a mantle around the root and an intercellular Hartig net. The study found that ECM host species from the Fagales order maintained the majority of AM-conserved genes, unlike other non-AM hosts. Transcriptome analysis revealed that several of these maintained genes were induced in ECM symbiosis, suggesting that ECM formation recruits AM-derived mechanisms. The study focuses on ECM-only hosts, which are plant species that exclusively engage in ECM symbiosis and have lost the ability to form AM symbiosis. The researchers discovered that ECM-only hosts maintain 64% of the AM-conserved orthologous groups (OGs), highlighting the importance of these genes in ECM symbiosis. They also identified specific genes, such as RAM2, involved in lipid biosynthesis and arbuscule formation in ECM roots. The study suggests that the preservation of AM-conserved genes in ECM-only hosts supports their role in ECM symbiosis. [Extracted from the article]

In the latest literature, climate models show that the conditions for pines, spruces, larches, and birches will deteriorate significantly. In Poland, as well as in other European countries, there are already signs of the decline of these species. This review article deals with the symbiotic relationships between fungi and plants, which can hardly be overestimated, using the example of pine trees. These are the oldest known symbiotic relationships, which are of great benefit to both components and can help plants, in particular, survive periods of severe drought and the attack of pathogens on the roots. This article describes symbioses and their causal conditions, as well as the mycorrhizal components of pine trees and their properties; characterizes ectomycorrhizal fungi and their mushroom-forming properties; and provides examples of the cultivation of pure fungal cultures, with particular attention to the specificity of the mycorrhizal structure and its effects on the growth and development of Pinus species. Finally, the role of mycorrhiza in plant protection and pathogen control is described. [ABSTRACT FROM AUTHOR]

Background: Water is one of the factors limiting rice cultivation on raindrop land. The provision of mycorrhizae can help the absorption of water in the soil solum deeper. Besides, it can also save the use of nitrogen and phosphor fertilizers in water-choked conditions. This research aimed to optimize dosage of nitrogen and phosphorus fertilizers on growth in rainfed lowland rice applied mycorrhizae. Methods: This research was carried out from April to July 2019 in rainfed lowland rice with entisol in Demangan, Sambi, Boyolali, Center Java, Indonesia The research method was a randomized complete block design (RCBD) with three replications. The first factor was the dosage of nitrogen fertilizer, which consisted of four levels, i.e., 0, 45, 90 and 135 kg ha-1. The second factor was the dosage of phosphorus fertilizer, which consisted of four levels, i.e., 0, 25, 50 and 75 kg ha-1. Result: The results showed that fertilizer dosage of nitrogen of 90 kg ha-1 and phosphorus of 50 kg ha-1 increased the leaf area index (LAI), leaf area duration (LAD), net assimilation rate (NAR), and crop growth rate (CGR). The application of nitrogen and phosphorus fertilizer can improve the Situ Bagendit variety's physiological character better than without fertilizer. Rice cultivation in rainfed lowland rice applied mycorrhizae should use nitrogen of 90 kg ha-1 and phosphorus of 50 kg ha-1. [ABSTRACT FROM AUTHOR]

Copyright of Forest Research is the property of Forest Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Forest Research is the property of Forest Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Anadolu Tarım Bilimleri Dergisi is the property of Ondokuz Mayis Universitesi, Ziraat Fakultesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Plant microbiomes play crucial roles in nutrient cycling and plant growth, and are shaped by a complex interplay between plants, microbes, and the environment. The role of bacteria as mediators of the 400-million-year-old partnership between the majority of land plants and, arbuscular mycorrhizal (AM) fungi is still poorly understood. Here, we test whether AM hyphae-associated bacteria influence the success of the AM symbiosis. Results: Using partitioned microcosms containing field soil, we discovered that AM hyphae and roots selectively assemble their own microbiome from the surrounding soil. In two independent experiments, we identified several bacterial genera, including Devosia, that are consistently enriched on AM hyphae. Subsequently, we isolated 144 pure bacterial isolates from a mycorrhiza-rich sample of extraradical hyphae and isolated Devosia sp. ZB163 as root and hyphal colonizer. We show that this AM-associated bacterium synergistically acts with mycorrhiza on the plant root to strongly promote plant growth, nitrogen uptake, and mycorrhization. Conclusions: Our results highlight that AM fungi do not function in isolation and that the plant-mycorrhiza symbiont can recruit beneficial bacteria that support the symbiosis. Aik4iJYbzAos1E2c5U4cFF Video Abstract [ABSTRACT FROM AUTHOR]

This study aimed to determine the effectiveness of the use of host plants in an effort to multiply mycorrhizal propagules indigenous to Gunung Ciremai National Park. The experimental method used a factorial complete randomized design with 2 factors. The first factor was the location of the source of inoculum by 3 levels: mixed forests, shrubs, and pine stands. The second factor was 4 types of host plant many as 4 levels: corn (Zea mays), sorghum (Sorghum bicolor. (L.) Moench), centro beans (Centrosema pubescens), and ruji beans (Pueraria javanica). Each treatment was repeated five times, so there were 60 experimental units. The spores were isolated by wet filtration and decantation methods adapted from Gerdemann and Nicolson (1963), followed by the modified sugar centrifugation method from Jenkins (1964). The observed parameter was the number of mycorrhizal spores. The data obtained were analyzed by a variance test (F test). To evaluate the treatment's effect and compare the selected treatments, Duncan's follow-up test was used at the level of 5%. The combination of the location of the shrub inoculum and the centro bean host plant showed the largest spore population, which was 222.60 per 50 g soil sample. Trapping techniques using host plants of corn, sorghum, centro beans, and ruji beans showed suboptimal results. The most common genera were Glomus (80%; 4 species), Gigaspora (10%, 1 species), and Acaulospora (10%, 1 species). Glomus was evenly found in all trapping results. [ABSTRACT FROM AUTHOR]

The coming century in agriculture will be marked by increasing exposure of crops to abiotic stress and disease due to climate change. The plant traits with the strongest potential to mitigate these stresses are complex, and are increasingly recognized to involve interaction with the microbiome. Through symbiosis with soil fungi, plants form arbuscular mycorrhizae (AM) that can alleviate nutrient, water, and temperature stress, and can confer pathogen resistance and increased yield. The portfolio of advantages offered by AM overlaps with the benefits of agriculturally useful plant traits that have been the subject of decades of intensive biotechnological efforts, such as C4 photosynthesis and rhizobial nitrogen fixation. In this article we illustrate the prospective benefits of genetic engineering to produce AM in nonmycorrhizal plants and modify AM in already-mycorrhizal crops. We highlight recent advances which have clarified the key genetic and metabolic components of AM symbiosis, and show that many of these components are involved in other plant biological processes and have already been subject to extensive genetic engineering in nonsymbiotic contexts. We provide a theoretical research roadmap to accomplish engineering of AM into the nonmycorrhizal model Arabidopsis including specific molecular genetic approaches. We conclude that AM is potentially more tractable than other complex plant traits, and that a concerted research initiative for biotechnological manipulation of AM could fill unique needs for agricultural resilience. Finally, we note that engineering of AM provides a potential back door into manipulation of other essential plant traits, including carbon storage, and beneficial microbiome assembly. [ABSTRACT FROM AUTHOR]

SUMMARY: Tree growth and survival are dependent on their ability to perceive signals, integrate them, and trigger timely and fitted molecular and growth responses. While ectomycorrhizal symbiosis is a predominant tree‐microbe interaction in forest ecosystems, little is known about how and to what extent it helps trees cope with environmental changes. We hypothesized that the presence of Laccaria bicolor influences abiotic cue perception by Populus trichocarpa and the ensuing signaling cascade. We submitted ectomycorrhizal or non‐ectomycorrhizal P. trichocarpa cuttings to short‐term cessation of watering or ozone fumigation to focus on signaling networks before the onset of any physiological damage. Poplar gene expression, metabolite levels, and hormone levels were measured in several organs (roots, leaves, mycorrhizas) and integrated into networks. We discriminated the signal responses modified or maintained by ectomycorrhization. Ectomycorrhizas buffered hormonal changes in response to short‐term environmental variations systemically prepared the root system for further fungal colonization and alleviated part of the root abscisic acid (ABA) signaling. The presence of ectomycorrhizas in the roots also modified the leaf multi‐omics landscape and ozone responses, most likely through rewiring of the molecular drivers of photosynthesis and the calcium signaling pathway. In conclusion, P. trichocarpa‐L. bicolor symbiosis results in a systemic remodeling of the host's signaling networks in response to abiotic changes. In addition, ectomycorrhizal, hormonal, metabolic, and transcriptomic blueprints are maintained in response to abiotic cues, suggesting that ectomycorrhizas are less responsive than non‐mycorrhizal roots to abiotic challenges. Significance Statement: Current research on tree physiology primarily focuses on tree responses to abiotic stress, with little emphasis on root‐associated mutualistic fungi. Our results provide insights into how and to what extent the presence of ectomycorrhizas modifies host responses to abiotic changes: symbiosis has local and systemic impacts on host signaling pathways. A better understanding of the molecular mechanisms underpinning root‐microbe mutualistic interactions under abiotic stress will allow for robust modeling of tree adaptation to environmental challenges. [ABSTRACT FROM AUTHOR]

In sustainable agricultural ecosystem management, a key focus is on minimizing chemical fertilizer use and maximizing the use of non-chemical alternatives. Our study was designed to explore the impact of mycorrhizal fungi and humic acid (HA) on the quantitative and qualitative characteristics of faba beans under varying chemical fertilizer levels. The experiment involved different treatments, which included HA and mycorrhiza in four variations (control, HA, HA+ mycorrhiza, and mycorrhiza alone), and nitrogen, phosphorus, and potassium (NPK) fertilizers at three different dosages (50%, 75%, and 100% of the recommended amount). The findings revealed that combining HA with mycorrhiza significantly influenced root colonization, with the highest chlorophyll a concentration (1.58 mg g-1) observed in the HA+ mycorrhiza treatment at 75% NPK. This treatment also led to the highest counts in seeds per pod, number of pods, and weight of 100 seeds. Between the 100% and 75% NPK levels in the HA+ mycorrhiza treatment, no significant differences were noted in terms of grain and biological yield. The greatest grain yields were measured at 4356 kg ha-1 and 4322 kg ha-1 for the HA+ mycorrhiza treatment at 100% and 75% NPK, respectively. Additionally, the highest concentrations of Fe, N, P, K, and Zn were observed with the HA+ mycorrhiza application at the 100% NPK level. [ABSTRACT FROM AUTHOR]

Millet is a cereal plant that's potential for rice substitution. This plant is adaptive to be cultivated in dry land but has a tolerance limit to drought stress. Mycorrhiza and phospate (P) fertilizer treatments help plants adapt to this condition. This study aimed to determine the effects of phosphate fertilizer and mycorrhiza as well as their interaction effects on the growth and yield of foxtail millet (Setaria italica L.) under drought stress. The experiment was carried out from January to June 2020 in the experimental farm, Faculty of Agriculture, University of Jenderal Soedirman. The research was arranged in a factorial randomized complete block design consisting of two factors. The first factor was the dose of SP-36 fertilizer per polybag, namely P0 = 0 g, P1 = 37,5 kg.ha-1 (25%), P2 = 75 kg.ha-1 = 0.88 g/polybag (50%), and P3 = 150 kg.ha-1. The second factor was the dose of mycorrhiza biofertilizer, namely M0 = 0 g.polibag-1, M1 = 33.3 g. polibag-1 and M2 = 66.6 g.polybag-1. The treatment was replicated three times. The data observed were analyzed using the F test, continued with DMRT test at p=0.05. The results showed that SP-36 fertilizer application at half of the recommended dose (0.88 g/polybag) could increase growth variables, such as leaf area, panicle length, and seed weight. Mycorrhizae application 33.3 g/polybag could improve variables such as plant height, leaf area, panicle length, and seed weight. It also accelerated the initiation of panicle emergence compared to control. [ABSTRACT FROM AUTHOR]

Orchid mycorrhizal fungi (OMF) are vital biocontrol agents, especially for Odontoglossum ringspot virus (ORSV). The promising study helped identify the mycorrhiza isolate from native tropical orchids and determine its potential as a biocontrol. Sample collection of healthy roots of Phalaenopsis amabilis emanated in Yogyakarta, Indonesia, carrying out molecular identification with rDNA-ITS amplification using a set of universal primers ITS1 and ITS4. In vivo, antagonist tests began by inoculating viruses and mycorrhiza to determine the effect of growth and induction of secondary metabolites. The result showed one isolate of Trichoderma sp. associated with the molecular analysis has amplified the ITS1-5.8S-ITS4 section by 600-750 bp DNA. The sequenced products revealed insertion and substitution occurrences, which may have caused the variance by strain diversity and potential severity. Indonesian isolates have undergone speciation and separation from other isolates by a substantial distance. The considerable effects were the increase in leaf length, leaf width, root length, leaf count, the number of roots, fresh weight, and a lowering of the virus content. The analysis of the plant growth parameters and virus concentrations provided significant differences among the treatments inoculated with orchid mycorrhiza (Mycorrhiza [M], Mycorrhiza + Virus [MV], and Virus + Mycorrhiza [VM]) and those without orchid mycorrhiza inoculation (Control [C] and Virus [V]). The orchid resistance suggested that the virus infecting plant leaves contain more phenolic chemicals. This study is the first-ever report of the Trichoderma sp. isolated from native tropical orchids in Indonesia. [ABSTRACT FROM AUTHOR]

Pearl millet, Pennisetum glacum treated with Mycorrhiza, Rhizobium, and Trichoderma microbes, could grow in highly contaminated mercury soil. Microbe-mediated tolerance of this plant and the mechanism involved was studied after growing pearl millet in 100 ppm of mercury-contaminated soil for 120 days. The different parameters analyzed were associated with photosynthesis and the stability of the cell membrane. Mercury contamination led to the inhibition of growth in the leaves and reduced photosynthesis and membrane stability. The defensive mechanism of P. glacum under mercury stress was aided by Mycorrhiza, Rhizobium, and Trichoderma and Hg-related toxicity in the soil was averted. Photosynthetic parameters such as chlorophyll a b, carotenoids, and anthocyanin were quantified. The stability and injury of the cell membrane were measured. The results showed a significant role of microbes in improving the tolerance of P. glacum against metal stress in the soil. [ABSTRACT FROM AUTHOR]

Copyright of Iraqi Journal of Desert Studies is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Forests in the northeastern US are experiencing shifts in community composition due to the northward migration of warm-adapted tree species and certain species' declines (for example, white ash and eastern hemlock) due to invasive insects. Changes in belowground fungal communities and associated functions will inevitably follow. Therefore, we sought to investigate the relative importance of two important tree characteristics—mycorrhizal type [ectomycorrhizal (EcM) or arbuscular mycorrhizal (AM)] and leaf habit (deciduous or evergreen) on soil fungal community composition and organic matter cycling. We sampled soil in the organic and mineral horizons beneath two AM-associated (Fraxinus americana and Thuja occidentalis) and two ECM-associated tree species (Betula alleghaniensis and Tsuga canadensis), with an evergreen and deciduous species in each mycorrhizal group. To characterize fungal communities and organic matter decomposition beneath each tree species, we sequenced the ITS1 region of fungal DNA and measured the potential activity of carbon- and nitrogen-targeting extracellular enzymes. Each tree species harbored distinct fungal communities, supporting the need to consider both mycorrhizal type and leaf habit. However, between tree characteristics, mycorrhizal type better predicted fungal communities. Across fungal guilds, saprotrophic fungi were the most important group in shaping fungal community differences in soils beneath all tree species. The effect of leaf habit on carbon- and nitrogen-targeting hydrolytic enzymes depended on tree mycorrhizal association in the organic horizon, while oxidative enzyme activities were higher beneath EcM-associated trees across both soil horizons and leaf habits. [ABSTRACT FROM AUTHOR]

The existing literature on symbioses involving microorganisms is biased towards describing the larger of the partners, even though it is often the microbial partner that determines fitness. It is possible to address size asymmetries between mutualistic partners through the scale-independent parameters, z and c, of species–area relationships (SARs). Some general questions and gaps in understanding which can be addressed with SARs are the spatial scales where spatial aggregation is observed whether SAR parameters are determined by environmental settings, and formulating null expectations for global diversity of endosymbionts. We highlight how SARs can be used to address key questions in arbuscular mycorrhizal symbioses, such as the relationship between fine-scale diversity of fungal symbionts on roots and plant fitness. Symbioses involving microorganisms prevail in nature and are key to regulating numerous ecosystem processes and in driving evolution. A major concern in understanding the ecology of symbioses involving microorganisms arises in the effectiveness of sampling strategies to capture the contrasting size of organisms involved. In many mutualisms, including mycorrhizas and gut systems, hosts interact simultaneously with multiple smaller sized mutualists, the identity of which determines success for the host. This complicates quantifying the diversity of mutualisms because sampling techniques fail to capture effectively the diversity of each partner. Here we propose the use of species–area relationships (SARs) to explicitly consider the spatial scale of microbial partners in symbioses, which we propose will improve our understanding of the ecology of mutualisms. [ABSTRACT FROM AUTHOR]

Species interactions exhibit varying degrees of specialization, ranging from generalist to specialist interactions. For many interactions (e.g., plantmicrobiome) we lack standardized metrics of specialization, hindering our ability to apply comparative frameworks of specificity across niche axes and organismal groups. Here, we discuss the concept of plant host specificity of arbuscular mycorrhizal (AM) fungi and ectomycorrhizal (EM) fungi, including the predominant theories for their interactions: Passenger, Driver, and Habitat Hypotheses. We focus on five major areas of interest in advancing the field of plant-mycorrhizal fungal host specificity: phylogenetic specificity, host physiology specificity, functional specificity, habitat specificity, and mycorrhizal fungal-mediated plant rarity. Considering the need to elucidate foundational concepts of specificity in this globally important symbiosis, we propose standardized metrics and comparative studies to enhance our understanding. We also emphasize the importance of analyzing global mycorrhizal data holistically to draw meaningful conclusions and suggest a shift toward singlespecies analyses to unravel the complexities underlying these associations. [ABSTRACT FROM AUTHOR]

This experiment aimed to investigate the effects of Pseudomonas growth-promoting bacteria, mycorrhizal fungi, and living mulch on morphological and physiological traits of a medicinal herb, Pimpinella anisum. The study was carried out using a factorial design in a randomized complete block design arrangement with three replications during the crop year of 2019-2020. The first factor includes the use of biological fertilizers (fungi and bacteria) at four levels: 1) control (without the use of biological fertilizers), 2) mycorrhizal fungi, 3) growth-promoting bacteria, 4) combined use of growth-promoting bacteria and fungi. The second factor includes mulch (plant residues) at four levels: 1) control, 2) wheat straw (3 t/ha), 3) berseem clover mulch (2 t/ha), 4) living berseem clover mulch, cultivated among the rows of anise. Cultivation of clover and anise was done simultaneously. Results showed that the combined use of biological fertilizers (Glomus intraradices and Pseudomonas putida) along with living clover mulch led to a significant increase in seed yield, harvest index, and the essential oil yield of anise. Moreover, under such conditions, the highest seed yield (930.8 kg/ha) and the highest essential oil yield (18.15 kg/ha) increased by 48% and 51% compared to the control, respectively. We found that the use of living clover mulch led to a significant increase in biological yield, seed yield, and the number of umbels and umbellets of anise. Accordingly, the highest biological yield of 5332 kg/ha was obtained, which was 55% higher than the control. The extraction of essential oil components showed that α-pinene and para-cymene showed the highest amount and significant components of essential oil. Moreover, the maximum amount of α-pinene (2.277%) observed upon fungi and living clover application along with inter-row clover cultivation (increased by 60% compared to the control), and the maximum value of para-cymene (0.2300%) was obtained upon bacteria and living clover inoculation along with inter-row clover cultivation (increased by 59% compared to the control). Finally, according to the perspectives of sustainable and organic agriculture in medicinal plant cultivation, the use of ecologically compatible inputs such as bacteria and fungi that stabilize food elements, as well as the use of living and non-living plant mulches, can be used as a tool to increase the quantitative and qualitative performance of the anise plant. [ABSTRACT FROM AUTHOR]

The effect of inoculating arbuscular mycorrhizal fungi (Glomus caledonium) on the growth, chlorophyll content, photosynthetic gas exchange parameters, and chlorophyll fluorescence characteristics of Malus royalty in the lead (Pb) contaminated soil was studied. The results showed that in Pb contaminated soil, the root activity of Malus royalty's decreased significantly. Moreover, as the Pb amount increased, the chlorophyll content, particularly the chlorophyll a content, fell dramatically. The PSII activity, especially Malus royalty leaves' the receptor side function (PSII receptor side), and photosynthetic carbon assimilation ability were significantly inhibited under Pb stress. The interaction rate of the root system of Malus royalty by G. caledonium was high. On inoculation, G. caledonium showed an increased mycorrhizal infection rate of 50-70%. The mycorrhizal interaction led to increased root activity in Malus royalty, which alleviated chlorophyll degradation in its leaves in Pb contaminated soil. G. caledonium infection showed improvement in the stomatal limitation of Malus royalty leaves in Pb contaminated soil, along with a rise in the tolerance of photosynthetic apparatus' to Pb and other nonstomatal factors to improve photosynthetic capacity. During Pb stress, the interaction improved the capacity of PSII for photosynthetic electron transport in Malus royalty leaves. It has been demonstrated that it somewhat increases the PSII receptor side OEC activity and QA to QB electron transfer ability in Malus royalty. Thus, it ensured relatively high activity of PS II in the inoculated leaves under Pb stress. Therefore, inoculation with G. caledonium can improve Malus royalty leaves' Pb tolerance and reduce the toxicity effect on photosynthetic function and morphological characteristics. [ABSTRACT FROM AUTHOR]

Soil organic carbon (C) is the largest active C pool of Earth's surface and is thus vital in sustaining terrestrial productivity and climate stability. Arbuscular mycorrhizal fungi (AMF) form symbioses with most terrestrial plants and critically modulate soil C dynamics. Yet, it remains unclear whether and how AMF–root associations (i.e., mycorrhizae) interact with soil minerals to affect soil C cycling. Here we showed that the presence of both roots and AMF increased soil dissolved organic C and reactive Fe minerals, as well as litter decomposition and soil CO2 emissions. However, it reduced mineral‐associated C. Also, high‐resolution nanoscale secondary ion mass spectrometry images showed the existence of a thin coating (0.5–1.0 μm thick) of 56Fe16O− (Fe minerals) on the surface of 12C14N− (fungal biomass), illustrating the close physical association between fungal hyphae and soil Fe minerals. In addition, AMF genera were divergently related to reactive Fe minerals, with Glomus being positively but Paraglomus and Acaulospora negatively correlated with reactive Fe minerals. Moreover, the presence of roots and AMF, particularly when combined with litter addition, enhanced the abundances of several critical soil bacterial genera that are associated with the formation of reactive minerals in soils. A conceptual framework was further proposed to illustrate how AMF–root associations impact soil C cycling in the rhizosphere. Briefly, root exudates and the inoculated AMF not only stimulated the decomposition of litter and SOC and promoted the production of CO2 emission, but also drove soil C persistence by unlocking mineral elements and promoting the formation of reactive minerals. Together, these findings provide new insights into the mechanisms that underlie the formation of reactive minerals and have significant implications for understanding and managing soil C persistence. [ABSTRACT FROM AUTHOR]

The aim of the study was to determine the effect of magnetically treated water (ATM) with a stationary magnetic field on the yield of tomato (Solanum lycopersicum L.) inoculated with three strains of arbuscular mycorrhizal fungi (AMF) infested with the nematode Meloidogyne incognita (Kofoid and White) Chitwood. The investigation began in a soft brown soil without carbonate, in the "Campo Antena" Protected Cultivation Unit, belonging to "América Libre" Socialist State Enterprise; between November 2018 and February 2019. The inoculation of the microorganisms was carried out at the time of the transplant, in a proportion of 10% with respect to the volume of the root ball. The experimental design was completely randomized blocks, with 8 treatments and four replicas, with a control without AMF inoculation, a treatment without AMF inoculation and irrigation with magnetically treated water, 3 treatments with inoculation with Glomus cubense, Rhizophagus irregularis, Fummeliformis mosseae, and 3 treatments with the inoculation of these 3 AMF species combined with irrigation with magnetically treated water with an induction of 0.07 T. The data obtained were processed in the statistical package R Commander by means of a simple analysis of variance, applying Duncan's Test of mean multiple comparison for p= 5. The results obtained showed the efficiency of the treatments applied in tomato yield, highlighting the treatment with G. cubense and ATM, which yielded 112.9 t·ha-1 and provided greater protection to the plant against the nematode attack by reducing the galling index to 1. [ABSTRACT FROM AUTHOR]

Açaí (Euterpe oleracea Mart., Arecaceae), a palm tree native to the Amazon basin, faces problems associated with its initial development, such as uneven germination and slow growth. The objective of this study was to evaluate the initial biometric development of açaí palm seedlings as a function of inoculation, or co-inoculation, with plant growth-promoting microorganisms. The experiment was carried out in a nursery and the treatments consisted of inoculation, or co-inoculation, of seedlings with arbuscular mycorrhizal fungi (Glomus sp. and Gigaspora sp.), diazotrophic bacteria (Azospirillum brasilense) and beneficial microorganisms©, applied in the rhizosphere of the seedlings. At 90 days after sowing, there were no statistical differences between treatments for any of the individual variables. However, hierarchical cluster analysis revealed the existence of four clusters. Shoot height (25.0 cm), leaf insertion height (12.0 cm) and root length (12.1 cm) tended to be slightly lower in non-inoculated seedlings (cluster 1). Inoculation of mycorrhizal fungi tended to promote the best development of seedlings, especially verified through root length (18.3 cm), but forming a cluster with diazotrophic bacteria (cluster 4). On the other hand, co-inoculation of mycorrhizae and diazotrophic bacteria tended to result in the lowest means, especially for shoot dry mass (0.20 mg) (cluster 3). The mix of beneficial microorganisms©, alone or co-inoculated, always formed a single cluster (cluster 2). Inoculation of açaí palm seedlings affects their initial development, but does not promote significant growth and development in a period of 90 days. [ABSTRACT FROM AUTHOR]

Background: In rice belts, cultivation of rice under aerobic conditions provides an alternative way to reduce the enormous amounts of water usage, by using 50 percent of the water when compared to traditional cultivation. However, micronutrient deficiencies are more common in aerobic rice during its early stages of growth. Mycorrhizal fungi were found to be efficient in mobilizing the nutrients under aerobic situations. Methods: The field experiment was conducted in Department of Agronomy, Tamil Nadu Agricultural University, Coimbatore. The experiment consisted of thirteen treatments which includes different recommended doses of VAM 50, 62.5 and 75kg ha-1 along with different combinations of foliar application of 0.5% urea, 0.5% ZnSO4 and 1% FeSO4. Result: The study revealed that combined application of 150 % of recommended dose of VAM and foliar application of 0.5% urea + 0.5% ZnSO4 + 1% FeSO4 at 25 and 45 DAS significantly increased the VAM colonization area, photosynthetic pigments and growth parameters such as plant height, shoot and root weight, root growth, leaf area index and yield attributes and it was found to be a better optionin rice cultivation to overcome the micronutrient deficiencies in its earlier stages under aerobic conditions. [ABSTRACT FROM AUTHOR]