Efficiency Of Arbuscular Mycorrhizal Fungi Research Articles

Co-inoculation of arbuscular mycorrhizal fungi and plant growth-promoting rhizobacteria can mitigate the effects of drought in wheat plants (Triticum durum)

Drought stress (DS) is one of the severe abiotic stresses that cause reductions in agricultural production. This study was conducted to examine the efficiency of arbuscular mycorrhizal fungi (M: consortium) and plant growth-promoting rhizobacteria (R: Z2 and Z4 strains, B: CHIN14, AAP22, AAP2, and CHIN15 strains), individually or in combination, as an appropriate strategy to improve durum wheat productivity under two water regimes: well-watered (75% FC) and DS (25% FC). DS exhibition reduced biomass, stomatal conductance, stem water potential, and increased malondialdehyde and hydrogen peroxide content. Under DS, AMF or B promoted plant growth, such as shoot height by 49 and 17%, respectively; by activating the photosynthetic mechanism and increasing the synthesis of proline content by 369% in plants treated with AMF, and antioxidant enzyme activities, such as polyphenoloxydase (PPO), in leaves by 36% in plant inoculated with B. After the experiment, total organic matter and carbon of the soil were improved by single application of B by 99 and 317%, respectively. This finding implies that the combination of mycorrhiza and PGPR regulates the physiological and biochemical processes utilized by wheat to cope with drought and improves the comprehension of the soil-plant relationship.

Single inoculation with arbuscular mycorrhizal fungi promotes superior or similar effects on cowpea growth compared to co-inoculation with Bradyrhizobium

• The single inoculation of R. clarus and C. etunicatum promoted the accumulation of nitrogen in the aerial part of both cultivars. • Inoculation with C. etunicatum resulted in higher phosphorus content in the shoot of the BRS Guariba cultivar. • Plants inoculated with C. etunicatum had similar or superior performance to plants fertilized with NPK or P. This study evaluated the efficiency of arbuscular mycorrhizal fungi (AMF) and the effect of co-inoculation with Bradyrhizobium on mineral accumulation and growth of two cowpea cultivars. The experimental design was a 12 × 2 factorial arranged in a completely randomized design, with four replications. The first factor consisted of 12 nutrient treatments: one control, four with AMF ( Rhizophagus clarus and Claroideoglomus etunicatum , inoculated individually and as a mixture, and AMF-based commercial inoculum) and four with AMF + rhizobia ( Bradyrhizobium sp. BR 3262); the second factor included two cowpea cultivars (BRS Novaera and Guariba), totaling 96 plots. Morphophysiological traits of plants, nitrogen and phosphorus accumulation in the aerial part, and symbiotic efficiency of microorganisms were evaluated. Double inoculation with C. etunicatum and R. clarus and the co-inoculation with Bradyrhizobium had no effect on height, shoot dry mass and N contents in the shoot of cowpea when compared to single inoculation with AMF. Positive effects of co-inoculation with Bradyrhizobium were verified for root dry mass in the treatments CE+B.BR 3262 and RC+CE+B.BR 3262, and for chlorophyll index and phosphorus content of the cultivar BRS Novaera in the nutrient treatment RC+CE+B .BR 3262. The nutrient treatment with single inoculation of R. clarus and C. etunicatum promoted the accumulation of nitrogen in the shoot for both cultivars. For the BRS Guariba cultivar, inoculation with C. etunicatum also resulted in higher phosphorus content. Overall, plants inoculated with C. etunicatum had a performance similar or superior to plants fertilized with NPK or P, resulting in greater mycorrhizal efficiency, which may be an alternative to conventional fertilization for cowpea cultivars BRS Novaera and BRS Guariba.

Enhancement of growth and Cannabinoids content of hemp (Cannabis sativa) using arbuscular mycorrhizal fungi.

This study aimed to investigate the efficiency of arbuscular mycorrhizal fungi (AMF) to promote growth and cannabinoid yield of Cannabis sativa KKU05. A completely randomized design (CRD) was conducted with six replications for 60 days. Two different species of AMF, Rhizophagus prolifer PC2-2 and R. aggregatus BM-3 g3 were selected as inocula and compared with two non-mycorrhizal controls, one without synthetic fertilizer and one with synthetic NPK fertilizer. The unfertilized non-mycorrhizal plants had the lowest performance, whereas plants inoculated with R. aggregatus BM-3 g3 performed best, both in terms of plant biomass and concentrations of CBD and THC. There were no significant differences in plant biomass and cannabinoid concentrations between non-mycorrhizal plants that received synthetic fertilizer and mycorrhizal plants with inoculum of R. prolifer PC2-2. Our data demonstrate the great potential for cannabis cultivation without risking deterioration of soil structure, such as soil hardening and increased acidity, which might be induced by long-term use of synthetic fertilizer.

Efficiency of Mycorrhiza Associated with Piper mullesua Plantlets under Acidic Soil Condition

The investigation was carried out to study the efficiency of arbuscular mycorrhizal fungi in up taking plant nutrients for the Piper mullesua Piper mullesua plantlets grown in acidic soil condition. In the present study, seedlings were infected with ten different strains of AM fungi and one without inoculation of AM fungi under controlled soil pH (4.5). Growth parameters and plant nutrients of AM infected plants were higher than those of non-mycorrhizal controls, which confirm the contribution of AM fungi. The two mycorrhizal fungal species G. macrocarpum and were most efficient in pH 4.5 and encouraged the growth of the plantlets . The correlation coefficient between plant G. hoi P. mullesua biomass and phosphatase activity was highly significant in case of associated with plantelts under acidic soil G. macrocarpum P. mullesuacondition which confirms potentiality of the fungal inoculums in acidic soil.

Efficiency of Arbuscular Mycorrhizal Fungi for the Growth Promotion of Sugarcane Under Pot Conditions

Efficiency of Arbuscular Mycorrhizal Fungi for the Growth Promotion of Sugarcane Under Pot Conditions

Integration Between Arbuscular Mycorrhizal Fungi, Bacterial and Fungal Bioagents for Controlling Rice Brown Spot Disease

The main purpose of this work was to test the efficiency of Arbuscular mycorrhizal fungi (AMF) in inducing systemic acquired resistance against rice brown spot disease alone or in combinations with the bioagents, Pseudomonas fluorescens (Pf) and Trichoderma viride (T.v.). In vitro test showed inhibition of 52.85% and 57.14%, respectively for the two selected bioagents with deformation and lysis for the pathogen spores. Under greenhouse conditions, the mixture of AMF + Tv and AMF + Pf + Tv, showed the highest efficiency in reducing the disease incidence after the fungicide treatment, whereas they achieved 65.60 and 48.40%, respectively. Field trials at two locations showed potentiality of AMF combined with the other bioagents in decreasing the percentages of disease incidence and severity. Also, the applied treatment increased the plant growth parameters, i.e., chlorophyll content, plant height and yield. Microscopic examination for rice plant roots showed colonization structures of AMF. Also, Pathogenesis related proteins had been defined.

Foraging speed and precision of arbuscular mycorrhizal fungi under field conditions: An experimental approach.

To better understand the ecology of arbuscular mycorrhizal (AM) symbiosis, we need to measure functional traits of individual fungal virtual taxa under field conditions. The efficiency of AM fungi in locating nutrient-rich patches in soil space is one of their central traits in this symbiotic relationship. We used plots of a long-term field experiment in grassland with manipulated functional group composition of host plant community to establish ingrowth patches with substrate free of roots and fungi and with varying nutrient availability. Comparison of the original AM fungal community before patch creation with that present 9weeks after patch establishment enabled us to estimate relative hyphal foraging speed for 41 fungal taxa, and a comparison of the fungal community in neighbouring patches differing in nutrient availability provided estimates of hyphal foraging precision for 22 taxa. Members of two dominant fungal families, Glomeraceae and Claroideoglomeraceae, differed in their foraging speed and precision. Glomeraceae taxa responded more slowly, but with a higher focus on enriched patches. We further demonstrated the usefulness of the obtained fungal functional traits by testing the differences between grass and dicotyledonous plant hosts using a data set obtained in another experiment at the same plots. Grass species hosted AM fungal communities with higher foraging speed, but lower foraging precision than the dicotyledonous species. Our study results support the use of field experiments for measuring comparative characteristics of AM fungi, which are highly elusive (or misrepresented) under controlled conditions.

Organic farming practices in a desert habitat increased the abundance, richness, and diversity of arbuscular mycorrhizal fungi ♣

Agricultural practices are known to affect the diversity and efficiency of arbuscular mycorrhizal fungi (AMF) in improving overall plant performance. In the present study we aimed to compare the abundance, richness, and diversity of AMF communities under organic farming of a desert ecosystem in the Arabian Peninsula with those of an adjacent conventional farming system and native vegetation. In total, 12 sites, including six plant species, were sampled from both farming systems and the native site. Spore morphotyping revealed 24 AMF species, with 21 species in the organic farming system, compared to 14 species in the conventional site and none from rhizosphere soil of a native plant (Tetraena qatarensis). The AMF spore abundance, species richness, and Shannon–Weaver diversity index were high under organic farming. In both systems, the AMF community composition and abundance associated with different crops followed similar trends, with pomegranates having the highest values followed by limes, grapes, mangoes, and lemons. Our results show that organic farming in such a desert ecosystem promotes AMF diversity. These data imply that AMF might play an important role in the sustainable production of food in resource-limited desert habitats.

Potential of arbuscular mycorrhizae and tall fescue in remediation of soils polluted with zinc

ABSTRACTA greenhouse experiment was carried out to investigate efficiency of tall fescue (Festuca arundinacea Schreb.) inoculated with arbuscular mycorrhizal fungi (AMF) to remediate soils polluted with zinc (Zn). Treatments consisted of four AMFs (control, Rhizophagus intraradices, Funneliformis mosseae and Glomus versiforme) and five levels of Zn (Z0: control, Z1: 10 mg kg−1, Z2: 50 mg kg−1, Z3: 100 mg kg−1 and Z4: 500 mg kg−1). The inoculation of tall fescue with F. mosseae and G. versiforme resulted in an increase in dry weight of shoots and uptake and concentration of shoot phosphorus) phosphorus (P) and Zn, while use of R. intraradices increased root dry weight and uptake of root Zn and P. The highest concentration of Zn in shoots was obtained in plants inoculated with F. mosseae. Root Zn concentration at all levels of Zn was significantly higher in plants inoculated with R. intraradices than other treatments. At 500 mg Zn kg−1, Zn translocation efficiency was higher in plants inoculated with F. mosseae, followed by G. versiforme, while most effective accumulation of Zn in roots was in plants inoculated with R. intraradices. Generally, efficiency of AMF in phytoremediation of Zn by plants mainly depends on fungal isolates and levels of Zn.

EFFICIENCY OF ARBUSCULAR MYCORRHIZAL FUNGI AND SOME SPECIES OF PLANT GROWTH PROMOTING RHIZOBACTERIA TO CONTROL FUNGI Fusarium chlamydosporum CAUSING AGENT OF DECLINE DATE PALM OFF SHOOTS

The objective of this study was to evaluation the efficiency of Arbuscular mycorrhizal fungi and some species of Plant growth promoting rhizobacteria (PGPR) to control Fusarium chlamydosporum fungus causing agent of decline date palm off-shoots. The isolation and identification results showed presence of F. chlamydosporum fungus from infected roots of infected palm trees and its major causing agent of diseases. The results appeared Pseudomonas fluorescens , Azotobacter chroococcum and Azosperillium sp. have high antagonism of pathogen under laboratory conditions. The evaluation results of biocontrol factors Glomus intraradices, G. mosseae, Gigaspora, P. fluorescens, A. chroococcum and Azospirillum sp. indicated that all treatments caused significant reduction in disease severity of death palm off-shoots disease into13.3-60.0%. compared to control (pathogen only) 86.7%. The interaction between G. intraradices and P. flourescens caused significant reduction in disease severity to 13.3% and enhanced the growth of foliage and root of offshoots length to 39.0 and 36.3cm respectively and increased the fresh and dry weight of foliage and root, 1.7750, 0.4977, 1.764 and 0.339g this result was closed to Beltanol fungicide effect. Also all biocontrol agents which used in this study alone (without pathogen) enhancement of plant growth compared with control treatment. The results of the current study showed for the first time that Arbuscular mycorrhizal fungi and Azospirillum sp. Bactrium to control and have good inhibition of Fusarium chlamydosporum fungus causing agent of decline date palm off-shoots and increasing plant growth in Iraq.

The Efficiency of Arbuscular Mycorrhizal Fungi in Promoting Alfalfa Growth in Acid Soils

High concentrations of soil Al3+ in acid soil severely influence the growth of Medicago sativa (alfalfa). The objective of the current study was to analyze whether Arbuscular Mycorrhizal Fungi (AMF) inoculation could improve alfalfa growth in acid soils. A two-way completely randomized factorial design was employed for M. sativa and M. lupulina (black medick) with two inoculations (rhizobia and AMF) and three Al3+ levels, and replicated four times. The soil Al3+ levels were adjusted to 900 mg/kg, 1000 mg/kg and 1100 mg/kg. Spores of AMF were isolated directly from rhizosphere soils of black medick. The rhizobia were isolated from root nodules in fields separately from two plant species. At each Al3+ level, there were four inoculations, non-inoculation, AMF solely, rhizobia solely and dual-inoculation with AMF and rhizobia. Soil Al3+ concentration significantly limited above- and below-ground growth of both alfalfa and black medick, reducing plant height, branching number, shoot and root weight, and root length, surface area and volume. Compared to rhizobia, AMF showed a higher tolerance to soil Al3+. AMF inoculation increased the shoot and root weight of both plant species under most circumstances. Overall, AMF colonization had a trend in increasing the contents of phosphorus in both plant species at all Al3+ concentrations but not nitrogen and potassium. Dual inoculation significantly increased nodulation ability, enabling both plant species to form nodules at 900 and 1000 mg/kg Al3+. Though the soil Al3+ concentration influenced the efficiency of AMF inoculation, AMF inoculation improved nodulation, increased plant growth and nutrient uptake, suggesting that it was an alternative way in improving alfalfa growth in acid soils.

Growth and nutrient accumulation in mycorrhized papaya seedlings cultivated in a phosphorus-fertilized substrate

ABSTRACT The indiscriminate use of mineral fertilizers in papaya orchards has increased production costs, and the use of arbuscular mycorrhizal fungi is a promising alternative to reduce such expenses. Therefore, the present research aimed at studying the efficiency of arbuscular mycorrhizal fungi (AMF) on dry matter and nutrient accumulation in Sunrise Solo papaya seedlings, by applying doses of P2O5 (triple superphosphate) that are harmful to the symbiosis. The experiment was carried out in a protected environment and was set up in a randomized block design with four replications, and consisted of four P2O5 doses (0, 672, 1386 and 2100 mg dm-3), three mycorrhizal fungi species (Gigaspora margarita, Entrophospora colombiana and Scutellospora heterogama) and the control treatment (mycorrhiza-free). Shoot and root dry matter as well as nitrogen, phosphorus and potassium contents in leaf and root tissues were assessed. Mycorrhizal inoculation promoted a 30% increase in shoot dry matter in relation to the control treatment. Mycorrhizal fungi promoted increases in leaf and root nitrogen content up to 672 mg dm-3 P2O5. Inoculation of E. colombiana favored the highest gains in root and shoot dry matter. P2O5 fertilization increased foliar and root phosphorus content.

Effects of Mycorrhizal Symbiosis on Growth Behavior and Carbohydrate Metabolism of Trifoliate Orange Under Different Substrate P Levels

The carbohydrate regulatory function of arbuscular mycorrhizal fungi (AMF), associated changes in root morphology, and substrate P level are important in the efficiency of AMF. A pot experiment was carried out to study the effects of AMF (Funneliformis mosseae) on growth response, root morphology, and sucrose metabolism of trifoliate orange [Poncirus trifoliata (L.) Raf.] seedlings under varying P substrate levels (0, 3, and 30 mM). Mycorrhizal inoculation stimulated growth performance, biomass production (root and shoot fresh weight), and various root morphological traits, regardless of substrate P level. AMF-induced sucrose accumulation in leaves was more highly positively correlated with leaf sucrose synthase (synthesis direction) activity in AMF than in non-AMF seedlings. Root glucose and fructose concentrations were significantly increased by AMF inoculation, independent of P level. Root colonization was more highly correlated with root glucose than with root fructose. AMF inoculation represented varied effects on activity of acid invertase and neutral invertase in leaves and roots at all the three P levels. These results indicated that AMF-accelerated better growth response and root morphological traits were independent of substrate P level, and AMF-induced sucrose cleavage was dependent on substrate P levels, plant tissue types, and sucrose-cleaving enzyme types.

Protozoa enhance foraging efficiency of arbuscular mycorrhizal fungi for mineral nitrogen from organic matter in soil to the benefit of host plants

Dead organic matter (OM) is a major source of nitrogen (N) for plants. The majority of plants support N uptake by symbiosis with arbuscular mycorrhizal (AM) fungi. Mineralization of N is regulated by microfauna, in particular, protozoa grazing on bacteria. We hypothesized that AM fungi and protozoa interactively facilitate plant N nutrition from OM. In soil systems consisting of an OM patch and a root compartment, plant N uptake and consequences for plant carbon (C) allocation were investigated using stable isotopes. Protozoa mobilized N by consuming bacteria, and the mobilized N was translocated via AM fungi to the host plant. The presence of protozoa in both the OM and root compartment stimulated photosynthesis and the translocation of C from the host plant via AM fungi into the OM patch. This stimulated microbial activity in the OM patch, plant N uptake from OM and doubled plant growth. The results indicate that protozoa increase plant growth by both mobilization of N from OM and by protozoa-root interactions, resulting in increased C allocation to roots and into the rhizosphere, thereby increasing plant nutrient exploitation. Hence, mycorrhizal plants need to interact with protozoa to fully exploit N resources from OM.

Diversity and efficiency of arbuscular mycorrhizal fungi in soils from organic chili (Capsicum frutescens) farms

No previous studies have been conducted on the diversity and population of arbuscular mycorrhizal fungi (AMF) in relation to organically grown chili (Capsicum frutescens L.) in Thailand. This study was carried out to investigate the diversity and status of AMF populations at four organically managed farms in Ubon Ratchathani and Sisaket provinces. The effects of each AMF species on the growth and nutrient uptake of chili grown in sterile, organically managed soil were determined. Fourteen AM fungal taxa belonging to the genera Acaulospora (4 spp.), Entrophospora (1 sp.), Glomus (7 spp.) and Scutellospora (2 spp.) were found. Among these, Glomus was the dominant genus found at all sites, followed by Acaulospora. The spore density and root colonization of AMF on chili did not vary significantly among the sites. The effects of ten selected AMF species on the growth of chili showed that Gl. clarum RA0305 increased the growth, flowering, and fruit production of chili, and also increased the P uptake significantly, compared to non-mycorrhizal plants. This fungus showed the highest potential as a promoter of growth, flowering and yield in organically managed chili production.

Effects of Soil Disturbance and Organic P on Mycorrhiza Development and Symbiotic Efficiency of Arbuscular Mycorrhizal Fungi

ABSTRACT Two experiments were designed to investigate the effects of soil disturbance and organic P (Na- phytate and lecithin) on mycorrhiza formation and symbiotic efficiency of AMF associated with maize in greenhouse. The results showed that P forms did not affect the root colonization of BEG167 and Glomus versifome (G.v) with maize. G.v produced more extraradical fungal biomass than BEG167 when KH2PO4 and lecithin were applied. The treatments with lecithin and KH2PO4 had higher maize biomass than those supplied with Na-phytate. BEG 167 and G.v differed in maize biomass contribution when Na-phytate was applied. Soil disturbance reduced significantly root colonization, and significantly or slightly decreased shoot biomass and P uptake of maize colonized by BEG141. However, mycorrhiza development and symbiotic efficiency of G.v were not influenced by soil disturbance. On cellulose acetate membrane, numerous regeneration hyphae with anastomosis structure and dichotomous structure were observed. The results suggested that rapid recovery of extraradical hyphae of AMF might compensate the P contribution loss caused by soil disturbance and buffer the decrease of propagule reserve in soil ecosystem.

Impairment of NtAQP1 gene expression in tobacco plants does not affect root colonisation pattern by arbuscular mycorrhizal fungi but decreases their symbiotic efficiency under drought

We investigated in two tobacco (Nicotiana tabacum) plant lines (wildtype or antisense mutant) whether impairment in expression of the plasma membrane aquaporin gene (NtAQP1) affects the arbuscular mycorrhizal (AM) fungal colonisation pattern or the symbiotic efficiency of AM fungi. These two objectives were investigated under well-watered and drought stress conditions. Both plant lines had a similar pattern of root colonisation under well-watered and drought stress conditions. In contrast, under drought stress, AM wildtype plants grew faster than mycorrhizal antisense plants. Plant gas exchange also appeared to depend on the expression of NtAQP1 and parallelled the determined growth increments. The implications of enhanced symplastic water transport via NtAQP1 for the efficiency of the AM symbiosis under drought stress conditions are further discussed.

Efeito de diferentes isolados fúngicos da mesma comunidade micorrízica no crescimento e absorção de fósforo em soja e trevo vermelho

Experimentos que testam a eficiência de fungos micorrízicos arbusculares (FMAs) provenientes de uma mesma amostra de solo complementam os estudos de diversidade taxonômica por promover relações funcionais dentro das comunidades micorrízicas. Neste estudo, isolados fúngicos de três comunidades distintas foram avaliados quanto a sua eficiência em aumentar a produção de biomassa e teor de P em dois hospedeiros micotróficos. No primeiro experimento, avaliou-se o efeito de 13 isolados de FMA pertencentes às comunidades JA205, MN414 e VA105, para testar a hipótese de que pelo menos um isolado de cada comunidade micorrízica seria eficiente para a soja. Todos os três isolados da comunidade JA205 e Glomus clarum da comunidade VA105 aumentaram a produção de biomassa seca em relação às plantas não micorrizadas. Os isolados da comunidade MN414 não influíram na produção de biomassa seca. A concentração de P, no entanto, foi significativamente aumentada por 7 dos 13 isolados em relação às plantas-controle. No segundo experimento, avaliou-se o efeito da inoculação separada e da co-inoculação de isolados das comunidades VA105 e MN414 em trevo. A colonização pelos cinco isolados de ambas as comunidades aumentou significativamente a produção de biomassa seca e conteúdo de P no trevo, com exceção de Scutellospora calospora MN414C que teve efeito apenas no conteúdo de P. A co-inoculação de isolados nem sempre produziu maior benefício do que a inoculação com isolados em separado. Plantas colonizadas com S. verrucosa VA105B + Glomus clarum VA105D produziram quantidade significativamente maior de biomassa do que plantas inoculadas com S. verrucosa apenas, mas não diferiram daquelas inoculadas com G. clarum. No outro extremo, a produção de biomassa seca e conteúdo de P não foram significativamente diferentes em plantas inoculadas com Glomus sp. MN414B + Gigaspora gigantea MN414D daquelas inoculadas com cada isolado separadamente. O teste da eficiência relativa de isolados fúngicos originados de uma mesma comunidade representa um primeiro passo para a adoção das estratégias de manejo de fungos nativos versus inoculação com isolados exóticos, visando aumentar a produtividade em ecosistemas naturais ou agrícolas.