Effects of arbuscular mycorrhizal fungi on maize (Zea mays L.) and sorghum (Sorghum bicolor L. Moench) grown in rare earth elements of mine tailings

Rare earth elements (REE) of mine tailings have caused various ecological and environmental problems. Revegetation is one of the most cost-effective ways to overcome these problems, but it is difficult for plants to survive in polluted tailings. Arbuscular mycorrhizal fungi (AMF) can provide biotic and abiotic stress tolerance to its host plant and has widely adopted for the revegetation of degraded ecosystems. However, little is known about whether AMF plays role in facilitating the revegetation of REE of mine tailings. The objective was to investigate the uptake of nutrients and REE when plants are inoculated with AMF. A greenhouse pot experiment was conducted on the effects of Glomus mosseae and Glomus versiforme for the growth, nutritional status, and uptake of REE and heavy metals by maize (Zea mays L.) or sorghum (Sorghum bicolor L. Moench) grown in REE of mine tailings. The results indicated that symbiotic associations were successfully established between AMF and the two plant species. G. versiforme was more effective than G. mosseae at promoting plant growth by significantly increasing the uptake of nitrogen (N), phosphorus (P), and potassium (K) and decreasing carbon:nitrogen:phosphorus (C:N:P) stoichiometry. The shoot and root dry weights of the two plant species were increased by 211–387% with G. versiforme inoculation. Maize and sorghum exhibited significant differences in the REE concentrations in response to the colonization by AMF. The shoot and root lanthanum (La), cerium (Ce), praseodymium (Pr), and neodymium (Nd) concentrations of the maize inoculated with G. versiforme were decreased by approximately 70%, whereas those in the roots of sorghum were increased by approximately 70%. G. mosseae only significantly decreased the La, Ce, Pr, and Nd concentrations in the maize shoots. Inoculation with AMF also significantly decreased the concentration of certain heavy metals in the shoots and roots of maize and sorghum. These findings indicate that AMF can alleviate the effects of REE and heavy metal toxicity on plants and enhance the ability of plants to adapt to the composite adversity of REE in mine tailings.     

Effects of Arbuscular Mycorrhizal Fungi on Growth and Yield of Cucumber Plants

Abstract

In two pot experiments, cucumber (Cucumis sativus L. cv. Jinlu No. 3) seedlings were each inoculated with one of three arbuscular mycorrhizal fungi (AMF), Glomus mosseae, Glomus intraradices, or Glomus versiforme, or uninoculated. Seedling growth and weight of single fruit were investigated. The results indicated that growth of seedlings was significantly enhanced by G. mosseae, inhibited by G. versiforme, and not significantly influenced by G. intraradices. The dry weight of seedlings inoculated with G. mosseae was 1.2 times its counterparts. The concentrations of nitrogen (N) and phosphorus (P) in roots and magnesium (Mg), copper (Cu), and zinc (Zn) concentration in shoots were increased by inoculating the three AMF, and potassium (K) and iron (Fe) concentrations in shoots decreased significantly. The weights of single fruit of plants preinoculated with G. mosseae and G. versiforme were about 1.4 and 1.3 times higher than those from the uninoculated treatment, respectively.     

Interactive effects of co-inoculation of Bradyrhizobium japonicum strains and mycorrhiza species on soybean growth and nutrient contents in plant

The main objective of this study was to investigate the effects of co-inoculation with different strains of Bradyrhizobium japonicum (i.e. Helinitro, Rizoking, and Nitragin) and arbuscular mycorrhizal fungi (AMF) species (i.e. Glomus fasciculatum, Glomus versiforme, Glomus intraradices, Glomus mosseae, and Glomus etunicatum) on soybean growth, fungal root colonization, and nutrient uptake of nitrogen (N), phosphorus (P), zinc (Zn), iron (Fe), and copper (Cu). Co-inoculation with various AMF species and rhizobia significantly (p<0.01) increased the soybean biomass production as compared to the non-inoculated controls. Furthermore, AMF colonization of roots of soybean plants increased by 79, 70.1, 67, 63, 57.5, and 50.1% in the presence of G. fasciculatum (GF), G. versiforme (GV), G. intraradices (GI), G. mosseae (GM), and G. etunicatum (GE), and Gmix (a mixed culture of fungi), respectively. Higher nutrient contents were observed in plants co-inoculated with Helinitro and GF. More insight into these results will enable optimization of the effective use of AM fungi in combination with their bacterial partners as a tool for increasing soybean yields in Iran; however, its general analytical framework could be applied to other parts of the world.     

Protecting Cucumber from Fusarium Wilt with Arbuscular Mycorrhizal Fungi

A pot experiment was conducted to investigate the biocontrol effects of arbuscular mycorrhizal fungi (AMF) Glomus mosseae and Glomus versiforme on Fusarium oxysporum wilt disease of cucumber (Cucumis sativus L.). The results indicated that both AMF improved the growth of cucumber seedlings and reduced disease severity, but G. versiforme was more efficient. Compared with nonmycorrhizal plants infected by F. oxysporum, shoots and roots dry weights increased by 100% and 80% in G. versiforme–inoculated plants, and the qualities of seedlings were significantly improved; meanwhile, nitrogen, phosphorus, and potassium contents in shoots of G. versiforme–inoculated plants were significantly greater than those of G. mosseae–inoculated plants and nonmycorrhizal plants. Moreover, for mycorrhizal plants, soluble sugar and free proline contents in mycorrhizal roots were significantly greater than those of nonmycorrhizal treatment; however, malonaldehyde content in roots and the quantity of fungi in rhizosphere decreased when the plants were attacked by F. oxysporum.     

Impact of Mycorrhizae Formation on the Phosphorus and Heavy-Metal Uptake of Alfalfa

Three pot experiments were set up to determine how efficiently mycorrhizal fungi affect the uptake, translocation, and distribution of labeled phosphorus (³²P), phosphorus (P), and heavy metals in alfalfa (Medicago sativa L.). In experiments 1 and 2, the efficiencies of different arbuscular mycorrhizal fungi (AMF) species including Glomus mosseae, G. etunicatum, G. intraradices and a mixed strain (G. mosseae, Gigaspora hartiga, and G. fasciculatum) on uptake, translocation, and distribution of ³²P and P in alfalfa were investigated, respectively. In a third experiment, the efficiency of G. mosseae on uptake and distribution of heavy metals [cadmium (Cd), cobalt (Co), lead (Pb), and combinations] was tested. Results of experiments 1 and 2 suggest that G. mosseae was the most effective at increasing the uptake of ³²P and P. Experiment 3 result showed that in the triple-metal-contaminated soil, inoculated plants had greater Co (32.56 mg kg^?1) and Pb (289.50 mg kg^?1) concentration and G. mosseae enhanced the translocation of heavy metals to shoot. Hence, mycorrhizal alfalfa in symbiosis with G. mosseae can be used for remediation of heavy metals polluted soils with high efficiency.     

Interactions between the arbuscular mycorrhizal fungus Glomus mosseae and plant growth-promoting fungi and their significance for enhancing plant growth and suppressing damping-off of cucumber (Cucumis sativus L.)

This study investigated the interactions between the arbuscular mycorrhizal fungus (AMF) Glomus mosseae and the plant growth-promoting fungi (PGPF) Penicillium simplicissimum GP17-2 and Trichoderma harzianum GT3-2 in relation to their colonization of roots and the rhizosphere of cucumber (Cucumis sativus L.), and their effect on plant growth and suppression of the damping-off pathogen Rhizoctonia solani. Combined inoculation of T. harzianum with G. mosseae increased the percentage of AMF root colonization, but the presence of P. simplicissimum had no significant effect on mycorrhizal formation. The existence of G. mosseae decreased the population development of T. harzianum in and/or around the roots, however, growth of P. simplicissimum was not affected. Both PGPF isolates were effective in increasing the plant shoot and root dry weight, G. mosseae, however, was not. Nevertheless, co-inoculation of G. mosseae with T. harzianum synergistically enhanced plant growth. A comparable additive effect on plant growth was not observed when P. simplicissimum was combined with G. mosseae. Treating plants with the PGPF either simultaneously with the pathogen or prior to pathogen infection suppressed damping-off disease. G. mosseae was significantly effective in reducing disease severity when inoculated prior to the pathogen but not when inoculated simultaneously with the pathogen. Interestingly, the levels of disease protection achieved by the single inoculation of P. simplicissimum, T. harzianum or G. mosseae were significantly increased by combined inoculation of each PGPF with G. mosseae.     

Pre-inoculation with arbuscular mycorrhizal fungi suppresses root knot nematode (<Emphasis Type="Italic">Meloidogyne incognita</Emphasis>) on cucumber (<Emphasis Type="Italic">Cucumis sativus</Emphasis>)

A pot experiment was conducted to evaluate the influence of pre-inoculation of cucumber plants with each of the three arbuscular mycorrhizal (AM) fungi Glomus intraradices, Glomus mosseae, and Glomus versiforme on reproduction of the root knot nematode Meloidogyne incognita. All three AM fungi tested significantly reduced the root galling index, which is the percentage of total roots forming galls. Numbers of galls per root system were significantly reduced only in the G. intraradices + M. incognita treatment. The number of eggs per root system was significantly decreased by AM fungus inoculation, no significant difference among the three AM fungal isolates. AM inoculation substantially decreased the number of females, the number of eggs g⁻¹ root and of the number of eggs per egg mass. The number of egg masses g⁻¹ root was greatly reduced by inoculation with G. mosseae or G. versiforme. By considering plant growth, nutrient uptake, and the suppression of M. incognita together, G. mosseae and G. versiforme were more effective than G. intraradices.     

The effects of simultaneous root colonisation by three Glomus species on soil pore characteristics

The spatial and temporal nature of the precise interactions between soil fungi and roots and their subsequent role in developing soil structure is still a subject where our understanding is limited. This research examines the relationship between three species of arbuscular mycorrhizal fungus (AMF) and soil structural characteristics. Plantago lanceolata was inoculated with one of: Glomus geosporum, Glomus mosseae or Glomus intraradices, and every combination of the fungal species. Infectivity was similar for each individual species, but G. mosseae and G. intraradices together resulted in the lowest per cent root length colonised. Despite the lower percentage colonisation, this combination induced the greatest mycorrhizal growth response. Aggregate stability and aggregate size distribution were unaffected by AMF but were increased by the presence of roots. Microbial biomass-C was also enhanced by roots. Pore size, pore size distribution and nearest neighbour distance were all reduced by G. mosseae and increased by G. intraradices. All AMF inocula containing G. intraradices resulted in greater distances between pores within the experimental soils. Porosity (%) was increased by G. mosseae suggesting that more, smaller pores with less distance between them enhanced overall porosity.     

Influence of Three Arbuscular Mycorrhizal Fungi and Phosphorus on Growth and Nutrient Status of Taro

Abstract

Glasshouse and field experiments were conducted with micropropagated (tissue culture) taro plants and germinated corms to determine the arbuscular mycorrhizal dependency of taro. The micropropagated plants (cultivar Laiyu 3) were transplanted in plastic pots (3‐L) containing a mixture of vermiculite:perlite:peat:sand (2:1:1:1) with 0 or 8000 units of inoculum potential (UIP) of Glomus mosseae (Nicol & Gerd) Gerdemann and Trappe, Glomus versiforme (Karsten) Berch or Gigaspora rosea Nicolson & Schenck. Budded corms were planted in clay pots (8.5‐L) containing sterilized sandy loam mixed with 0 or 12,000 UIP of G. mosseae or G. versiforme, and 0 or 5 g Ca₃(PO₄)₂ were added. In a field experiment, budded corms were placed in paper pots (0.5‐L) with sterilized sandy loam mixed with 0 or 4000 UIP of G. mosseae or G. versiforme and then planted directly in the field. Inoculation with AM fungi significantly increased survival rate and growth of tissue culture taro plants, and the contents of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), copper (Cu), and zinc (Zn), enhanced the formation of corms, numbers of second and third branch corms and corm yield, and enhanced the contents of crude protein, starch, and amino acids in the corms. Phosphorus fertilizer slightly increased plant yield but reduced plant absorption of Cu and Zn and root colonization by the AM fungi. Relative mycorrhizal dependence (RMD) of micropropagated plants was greater than that of corms.     

Effects of Arbuscular Mycorrhizal Fungi and Ammonium: Nitrate Ratios on Growth and Pungency of Onion Seedlings

ABSTRACT

A pot experiment was conducted to study the growth and pungency of Allium cepa L. grown in Perlite as affected by colonization by the arbuscular mycorrhizal (AM) fungi Glomus versiforme and Glomus intraradices BEG141 and by ammonium:nitrate (NH₄ ⁺:NO₃ ^?) ratios of 3:1, 1:1, and 1:3 in 4 mM solutions. Plants were harvested when bulb formation commenced. In general, mycorrhizal colonization resulted in increased shoot dry weight, shoot length, sheath diameter, root nitrogen (N) and phosphorus (P) content (except with G. intraradices and a NH₄ ⁺:NO₃ ^? ratio of 1:3), shoot N and P concentrations (except with G. versiforme and a NH₄ ⁺:NO₃= ratio of 3:1) and content. Plants inoculated with G. versiforme had higher growth parameters and N and P content than those with G. intraradices, whereas N and P concentrations showed the opposite trends. Growth parameters and N and P content of non-mycorrhizal plants were highest at a NH₄ ⁺:NO₃= ratio of 1:3, while those of plants inoculated with G. versiforme or G. intraradices were highest at a ratio of NH₄ ⁺:NO₃ ^? 3:1 or 1:1. Neither mycorrhizal colonization nor proportion of inorganic N species significantly affected bulb enzyme-produced pyruvate or total or organic sulfur (S) concentrations in plant shoots. Colonization by AM fungi made a substantial contribution to onion growth and may not have been directly related to bulb pungency at early stages of plant growth. However, the influence of AM fungi on plant N and P metabolism may have implications for onion flavor at later stages of plant growth.     

Arbuscular Mycorrhizal Fungi Contribute to Resistance of Upland Rice to Combined Metal Contamination of Soil

A greenhouse pot experiment was conducted to investigate heavy metal [copper (Cu), zinc (Zn), lead (Pb), and cadmium (Cd)] uptake by two upland rice cultivars, ‘91B3’ and ‘277’, grown in a sterilized field soil contaminated by a mixture of Cu, Zn, Pb, and Cd. Rice plants were inoculated with each of three arbuscular mycorrhizal fungi (AMF), Glomus versiforme (GV), Glomus mosseae (GM), and Glomus diaphanum (GD), or remained noninoculated (NM). Both rice cultivars could be colonized by the three AMF used in this experiment. The percentage of mycorrhizal colonization by the three AMFs on the two rice cultivars ranged from 30% to 70%. Mycorrhizal colonization of both upland rice cultivars had a large influence on plant growth by increasing the shoot and root biomass compared with non-inoculated (NM) plants. The results indicate that mycorrhiza exert some protective effects against the combined toxicity of Cu, Zn, Pb, and Cd in the contaminated soil. This conclusion is supported by the partitioning of heavy metals (HMs) in the two cultivars. In the two cultivars, colonization by AMF reduced the translocation of HMs from root to shoot (except that the colonization of AMF increased the Cu translocation of HMs in cultivar ‘277’). Immobilization of the HMs in roots can alleviate the potential toxicity to shoots induced by the mixture of Cu, Zn, Pb, and Cd. The two rice cultivars showed significant differences in uptake of Cu, Zn, Pb, and Cd when uninoculated. GM inoculation gave the most protective effects on the two cultivars under the combined soil contamination.     

Physiological characteristics (SDH and ALP activities) of arbuscular mycorrhizal colonization as affected by Bacillus thuringiensis inoculation under two phosphorus levels

The effect of Bacillus thuringiensis (B.t.) inoculation on plant growth and on the intra- and extraradical mycorrhizal development of lettuce roots colonized by Glomus mosseae or Glomus intraradices was examined in an inert, soil-less substrate. Histochemical determination of succinate dehydrogenase (SDH) and alkaline phosphatase (ALP) activities which indicate active fungal metabolism was carried out at two phosphorus (P) levels. The presence of B.t. increased extra- and intraradical colonization [measured as frequency (%F), intensity (%I) and percentage of arbuscules (%A)] for both arbuscular mycorrhizal fungi (AMF) rather than plant growth or nutrition regardless P level. Under the lowest level of P fertilization, B.t. enhanced to a similar extent the extra- and intraradical development of both endophytes, but the proportion of fungal tissue showing SDH or ALP was increased in G. intraradices-colonized plants. [SDH: 458% (M) and 512% (A); ALP: 358% (M) and 300% (A)]. P supply decreased G. intraradices colonization to a higher extent than G. mosseae. Nevertheless, the totality of G. intraradices structures developed in P-amended medium showed intraradical o extraradical activity, while in G. mosseae-colonized roots, SDH and ALP activities highly decreased relative to fungal tissue determined by TB staining as affected by P. Our results show that bacterial inoculation compensates the negative effect of P on the intraradical fungal growth and vitality. P amendment reduced in a higher extent G. intraradices infection intensity (non-vital and vital staining) and G. mosseae activity (ALP staining). Thus, big differences in the proportion of SDH-active infection showing ALP activity in mycelium developed by each endophyte were noted at the highest P level. Physiological plant parameters such as photosynthetic activity did not explain specific changes on each arbuscular-mycorrhizal fungus as affected by P or B.t. inoculation. The increased extraradical mycelium development and metabolic fungal activity as a result of B.t. inoculation positively affected N and P plant content and photosynthetic rate in G. intraradices-colonized plants under the lowest P conditions. In general, the increased metabolically active fungal biomass in co-inoculated plants was irrespective of P level and was not related to the P plant uptake from the inert soil-less substrate. These results show the bacterial effect increasing the physiological and metabolic status of AM endophytes, which not only confirms but also extends previous findings on arbuscular mycorrhizae-bacteria interactions. The present study emphasizes the ecological and practical importance of rhizosphere free-living bacteria as mycorrhizae-helper microorganisms.     

Beneficial effects of earthworms and arbuscular mycorrhizal fungi on establishment of leguminous trees on Pb/Zn mine tailings

Planting trees to stabilize metalliferous mine tailings is a widely used form of land reclamation although substantial soil amendment is invariably required, both to improve the physico-chemical status of the tailings and to ameliorate toxicity prior to planting. Here, we report a glasshouse study of the combined effects of burrowing earthworms (Pheretima guillelmi) and arbuscular mycorrhizal fungi (Glomus spp., AMF) on establishment of a naturally invasive, woody, nitrogen-fixing legume, Leucaena leucocephala, on topsoil-amended Pb/Zn mine tailings. AMF provided the most effective preliminary inoculant, improving N, P and K uptake, but earthworms had more influence improving N nutrition. In most cases, the combined effects of AMF and earthworms were additive and proved to be beneficial to plant growth, plant nutrition and for protection against uptake of toxic metals. AMF influenced metal uptake more than earthworms, but together they reduced mobility of Pb and Zn in soil by as much as 25%. Some minor but significant negative interactions were also evident; for example, earthworms enhanced soil microbial activity but inhibited the beneficial effects of AMF on N₂-fixation. We argue that increased attention to ecological interactions in soil could reduce costs and improve the efficacy of restoring a vegetation cover to land impacted by contaminated spoils.     

Cyamopsis tetragonoloba L Taub inoculated with arbuscular mycorrhiza and Pseudomonas fluorescens and treated with mustard oil cake overcome Macrophomina root-rot losses

The effects of inoculation of three arbuscular mycorrhizal (AM) fungi namely, Glomus mosseae, Glomus sinuosum, and Scutellospora erythropa in addition to Pseudomonas fluorescens and treatment with mustard oil cake on root-rot disease of Cyamopsis tetragonoloba L plants caused by Macrophomina phaseolina were evaluated under polyhouse conditions for 2 years. Inoculations of an arbuscular mycorrhizal fungi (AMF) in combination with P. fluorescens and mustard oil cake showed best supporting biocontrol system against the root-rot disease besides increasing the plant height, weight, and yield. The biocontrolling efficiency of dual inoculation (AMF + P. fluorescens) was the second best combination followed by AM plus mustard oil cake. Among the three AM fungi, G. mosseae inoculations showed the best results. Different combined AMF inoculations also altered the concentrations of total soluble sugars, orthodihydric phenols, flavonols, and epicuticular wax contents in host plants.     

Effect of indigenous arbuscular mycorrhizal fungi combined with manure on the change in concentration some mineral elements in cotton (Gossypium hirsutum L.)

A pot experiment was conducted to evaluate the effect of indigenous arbuscular mycorrhizal fungi (AMF) and the synergy of indigenous AMF and sheep manure (SM) on potassium (K), calcium (Ca) and some micronutrient concentrations in cotton plant. Indigenous AMF were a mixture of Glomus viscosum, Glomus mosseae and Glomus intraradices initially isolated from a cotton field. Cotton was grown for 12 weeks and the elements of shoot were determined at three stages of plant growth. Inoculated cotton plants with AMF had higher concentrations of K, Ca, manganese (Mn), iron (Fe), copper (Cu) and zinc (Zn) than non-mycorrhizal plants. Shoot concentrations of these elements increased significantly when SM was added to mycorrhizal plants. Maximum plant micronutrient uptake was found in the treatment of AMF inoculation with SM. Mn, Fe, Cu and Zn uptake increased significantly by 457%, 282%, 272% and 295%, respectively, over control. Indigenous AMF combined with SM resulted in better plant growth and micronutrient uptake.     

The combined effects of earthworms and arbuscular mycorrhizal fungi on microbial biomass and enzyme activities in a calcareous soil spiked with cadmium

Earthworms and arbuscular mycorrhizal fungi (AMF) are known to independently affect soil microbial and biochemical properties, in particular soil microbial biomass (SMB) and enzymes. However, less information is available about their interactive effects, particularly in soils contaminated with heavy metals such as cadmium (Cd). The amount of soil microbial biomass C (MBC), the rate of soil respiration (SRR) and the activities of urease and alkaline phosphatase (ALP) were measured in a calcareous soil artificially spiked with Cd (10 and 20 mg Cd kg⁻¹), inoculated with earthworm (Lumbricus rubellus L.), and AMF (Glomus intraradices and Glomus mosseae species) under maize (Zea mays L.) crop for 60 days. Results showed that the quantity of MBC, SRR and enzyme activities decreased with increasing Cd levels as a result of the elevated exchangeable Cd concentration. Earthworm addition increased soil exchangeable Cd levels, while AMF and their interaction with earthworms had no influence on this fraction of Cd. Earthworm activity resulted in no change in soil MBC, while inoculation with both AMF species significantly enhanced soil MBC contents. However, the presence of earthworms lowered soil MBC when inoculated with G. mosseae fungi, showing an interaction between the two organisms. Soil enzyme activities and SRR values tended to increase considerably with the inoculation of both earthworms and AMF. Nevertheless, earthworm activity did not affect ALP activity when inoculated with G. mosseae fungi, while the presence of earthworm enhanced urease activity only with G. intraradices species. The increases in enzyme activities and SRR were better ascribed to changes in soil organic carbon (OC), MBC and dissolved organic carbon (DOC) contents. In summary, results demonstrated that the influence of earthworms alone on Cd availability is more important than that of AMF in Cd-polluted soils; and that the interaction effects between these organisms on soil microorganism are much more important than on Cd availability. Thus, the presence of both earthworms and AMF could alleviate Cd effects on soil microbial life.     

Enhancement of Lead Uptake by Fenugreek Using EDTA and Glomus mosseae

The influence of Glomus mosseae supplemented with ethylenediaminetetraacetic acid (EDTA) on lead (Pb) uptake by Fenugreek (Trigonella foenum-graecum) was studied under pot conditions in a 2?×?2?×?5 factorial design with two AM treatments (G. mosseae inoculated and uninoculated), two EDTA concentrations (without and with 2.5 mmol EDTA kg^?1), and five lead concentrations (0, 50, 100, 400, and 800 mg kg^?1). A negative interaction was found between increasing lead concentration and G. mosseae. The plant dry matter and chlorophyll content was enhanced by G. mosseae whereas G. mosseae with EDTA showed the greatest root and shoot phosphorus (P) content. Ethylenediaminetetraacetic acid significantly enhanced lead concentration in the plant; however, at the same time it resulted in a slight decrease in the dry matter. However, when EDTA was applied along with G. mosseae, the deleterious effect of EDTA was overcome by the G. mosseae by promoting mineral uptake and plant growth, and hence metal accumulation also increased.     

Effects of mycorrhizal inoculation of upland rice on uptake kinetics of arsenate and arsenite

We assessed the effect of mycorrhizal inoculation on short‐term uptake kinetics of arsenate and arsenite by excised roots of upland rice (Oryza sativa L. cv. Zhonghan 221). A concentration of 0.01–0.05 mM arsenic (As) differentially affected the influx rates of both arsenate and arsenite into rice roots non‐inoculated or inoculated with Glomus mosseae and G. versiforme. While V_max for arsenate uptake by non‐mycorrhizal roots was 1.02 µmol g^?1 fresh weight h^?1, it was reduced by a factor of 2.4 for mycorrhizal roots (about 0.42 µmol g^?1 fresh weight h^?1) in the high‐affinity uptake system. However, at high concentrations of 0.5–2.5 mM As only G. versiforme was able to reduce As influx. The results show that mycorrhizal effects on As uptake of upland rice are both concentration and species‐specific.     

Growth Response and Nutrient Uptake of Eriobotrya japonica Plants Inoculated with Three Isolates of Arbuscular Mycorrhizal Fungi Under Water Stress Condition

Mycorrhizal technique is a promising biotechnology in horticultural industry, benefiting plants exposed to diverse abiotic stresses. In this study, the effects of three arbuscular mycorrhizal fungi (AMF), Acaulospora laevis, Glomus mosseae, and Glomus caledonium on plant growth and nutrient uptake of loquat (Eriobotrya japonica Lindl.) seedlings under three water regimes (well watered, water stressed-slight, water stressed-heavy) were investigated. Results showed that inoculated seedlings had higher dry biomass, plant height, and total leaf areas than those un-inoculated ones. AMF effect was the greatest for water stressed-heavy seedlings, followed by water stressed-slight seedlings and well watered seedlings. All AMF species increased the uptake of nitrogen (N) potassium (K), phosphorus (P), calcium (Ca), magnesium (Mg), zinc (Zn), copper (Cu), and the mycorrhizal contributions to the nutrient uptake were positively related to that to the biomass. Data suggest that AMF inoculation increases the tolerance of loquat seedlings to drought stress, and the improved nutrient uptake by AMF contributes greatly to the tolerance.     

Growth and Fruit Chemical Characteristics of Blackberry (Rubus Fruticosus) Cultivated with Vermicompost,Glomus Mosseae and Phosphate Rock

Abstract

The aim of this investigation was to determine the effect of vermicompost (V) and phosphate rock (PR) on blackberry (Rubus fruticosus L. agg.) plants inoculated with Glomus mosseae (Nicol. & Gerd.) Gerdemann & Trappe (AMF). Plant growth parameters, total phenol compounds and total flavonoids were evaluated on leaves. Anthocyanin contents, soluble solids (SS), pH, titratable acidity (TA) and SS/TA ratio was evaluated in blackberries fruits. Blackberry plants were obtained from cuttings from field plants, which were distributed in soil according to a randomized complete block design with three repetitions. Treatments were vermicompost (10?g plant^?1), phosphate rock (1?g plant^?1), Glomus mosseae (AMF), (1?g plant^?1), PR + AMF, V + PR, V +AMF, V + PR+ AMF and control without any amended. Plant height and stem diameter were measured five months after treatments, while total phenols and total flavonoids in leaves were evaluated eight months later. Anthocyanins, SS, pH, and TA were determined in blackberry fruits ten months after. Plant height was not statistically affected (p≤0.05), although total phenol compounds were higher (21.1?mg g^?1 dry plant) in the V+PR+AMF treatment, whereas the V + AMF treatment produced more dry plant total flavonoids (1.4?mg g^?1), compared with control plants. Blackberries produced with the vermicompost treatment had more anthocyanins (9.54?mg g^?1) than control plants. Soluble solids, pH and titratable acidity were not statistically (p≤0.05) affected by any treatment.