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Sample records for vesicular-arbuscular mycorrhizae vam

  1. Influence of vesicular arbuscular mycorrhiza (VAM) and phosphate ...

    African Journals Online (AJOL)

    A field experiment was carried out to find out the effect of biofertilizers, vesicular arbuscular mycorrhiza (VAM), and phosphate solubilising bacteria (PSB) individually and in combination on growth and physiological attributing properties of Marsdenia volubilis plant under nursery conditions. The plant seedlings were ...

  2. APPARENT LACK OF VESICULAR-ARBUSCULAR MYCORRHIZA (VAM) IN SEAGRASSES ZOSTERA MARINA L. AND THALASSIA TESTUDIUM BANKS EX KONIG

    Science.gov (United States)

    We examined two populations of Zostera marina L. and one of Thalassia testudinum Banks ex Konig for presence of vesicular-arbuscular mycorrhiza (VAM). None of these plants showed any VAM colonization. In addition, we were unable to find any literature references on the presence o...

  3. Vesicular-Arbuscular Mycorrhiza in Field-Grown Crops

    DEFF Research Database (Denmark)

    Jakobsen, Iver

    1986-01-01

    The importance of vesicular-arbuscular mycorrhiza (VAM) and P fertilizer for P nutrition and dry matter production in field peas (Pisum sativum L.) was studied in moderately P-deficient soil. Half of the experimental plots were fumigated to reduce the level of VAM infection. Shoots and 0 to 30 cm...... in fumigated plots, although both it and P uptake were increased by adding P fertilizer. The possible reasons for this discrepancy are discussed. A supplementary survey on infection development at five other field sites showed that peas are extensively colonized by VAM fungi, even in soils where a standard...

  4. The development and significance of vesicular-arbuscular mycorrhizas as influenced by agricultural practices

    NARCIS (Netherlands)

    Ruissen, M.A.

    1982-01-01

    The development and significance of vesicular- arbuscular mycorrhizas (VAM) in wheat and potatoes have been studied in relation to various farming systems and agricultural practices. The effects of farming systems on VAM have been observed on three neighbouring experimental farms in the vicinity of

  5. Vesicular-Arbuscular Mycorrhiza in Field-Grown Crops. I. Mycorrhizal Infection in Cereals and Peas at Various Times and Soil Depths

    DEFF Research Database (Denmark)

    Jakobsen, Iver; Nielsen, N.E.

    1983-01-01

    Development of infection by vesicular-arbuscular mycorrhiza (VAM) was studied in some field-grown crops. An infection plateau was reached within the first month after seedling emergence of spring barley, oats and peas. During the rest of the growth period the proportion of root length infected...

  6. Survey of vesicular-arbuscular mycorrhizae in lettuce production in relation to management and soil factors

    Science.gov (United States)

    Miller, R.L.; Jackson, L.E.

    1998-01-01

    The occurrence of vesicular-arbuscular mycorrhizae (VAM) root colonization and spore number in soil was assessed for 18 fields under intensive lettuce (Lactuca sativa L.) production in California during July and August of 1995. Data on management practices and soil characteristics were compiled for each field, and included a wide range of conditions. The relationship between these factors and the occurrence of VAM in these fields was explored with multivariate statistical analysis. VAM colonization of lettuce tended to decrease with the use of chemical inputs, such as pesticides and high amounts of P and N fertilizers. Addition of soil organic matter amendments, the occurrence of other host crops in the rotation, and soil carbon:phosphorus and carbon:nitrogen ratios, were positively associated with VAM colonization of lettuce roots. The number of VAM spores in soil was strongly correlated with the number of other host crops in the rotation, the occurrence of weed hosts and sampling date, but was more affected by general soil conditions than by management inputs. Higher total soil N, C and P, as well as CEC, were inversely related to soil spore number. A glasshouse study of the two primary lettuce types sampled in the field showed no significant differences in the extent of root colonization under similar growing conditions. The results of this study are compared with other studies on the effects of management and soil conditions on mycorrhizal occurrence in agriculture.

  7. The beneficial effect of dual inoculation of vesicular-arbuscular mycorrhizae + rhizobium on growth of white clover

    Directory of Open Access Journals (Sweden)

    Lin, XG.

    1993-01-01

    Full Text Available Investigation on the effect of phosphorus on vesicular-arbuscular mycorrhizal infection, and dual inoculation of vesicular-arbuscular mycorrhizae + rhizobium on growth of white clover under field microplots and pot experiments was conducted on fluvo-aquic soils of semi-arid region in north China. The results showed that 60 kg P205 ha in form of superphosphate was the most favorable phosphorus level for vesicular-arbuscular mycorrhizal infection ; mycorrhizal infection, nodulation, dry weight of shoots and roots, total uptake of nitrogen, phosphorus and other elements, the final yields and recovery of phosphorus of white clover were significantly increased by vesicular-arbuscular mycorrhizal inoculation and dual inoculation with vesicular-arbuscular mycorrhizal fungi and rhizobium. The highest response of inoculation was obtained by adding fertilizer phosphorus at the level of 60 kg P205 ha in form of superphosphate.

  8. The influence of vesicular-arbuscular mycorrhizas on production ...

    African Journals Online (AJOL)

    arbuscular mycorrhizas produced slight increases in dry mater production in unsterilized field plots at Cedara, Natal. Phosphorus levels in plant tops showed no increases due to mycorrhizas but crude protein content of all mycorrhizal plants were ...

  9. The Effects of Vesicular-Arbuscular Mycorrhizae on the Plant Growth and Nutrient Uptake of Cucumber

    OpenAIRE

    ÇIĞŞAR, Sibel; Sari, Nebahat

    2014-01-01

    This study was conducted to investigate the effect of vesicular-arbuscular (VA) mycorrhizae on plant growth of cucumber. Yayla F 1 seeds were sown in sterile and non-sterile growing medium (organic manure:soil:mix of sand; v:v:v 1:1:1). The mix inoculum of Glomus mosseaand Glomus fasciculatumspores (10 g/plant) was placed 5 cm below the cucumber seed before sowing. In order to investigate the effects of VA mycorrhizae on plant growth, plant height, diameter, number of nodes were measured ...

  10. Seasonality of vesicular-arbuscular mycorrhizae in sedges in a semi-arid tropical grassland

    Science.gov (United States)

    Muthukumar, T.; Udaiyan, K.

    2002-10-01

    Vesicular-arbuscular mycorrhizal (VAM) colonization and spore numbers in the rhizosphere of Cyperus iria L. and C. rotundus L., growing in a semi-arid tropical grassland, was studied during the 1993 and 1994 monsoons. In addition, climatic and chemical properties of the soils were determined in order to investigate their influence on mycorrhizal variables. VAM fungal association in the sedges was confirmed by plant- and root-trap culture techniques. The soil nutrients exhibited seasonal variations, but were highly variable between years. Intercellular hyphae and vesicles with occasional intraradical spores characterized mycorrhizal association in sedges. Dark septate fungi also colonized roots of sedges. Temporal variations in mycorrhizal colonization and spore numbers occurred, indicating seasonality. However, the patterns of mycorrhizal colonization and spore numbers were different during both the years. The VAM fungal structures observed were intercellular hyphae and vesicles. Changes in the proportion of root length with VAM structures, total colonization levels and spore numbers were related to climatic and edaphic factors. However, the intensity of influence of climatic and soil factors on VAM tended to vary with sedge species.

  11. Vesicular-arbuscular mycorrhiza response to crossed carbon and phosphorus resource gradients

    Energy Technology Data Exchange (ETDEWEB)

    Whitbeck, J.L. (Pennyslvania State Univ., University Park, PA (United States))

    1994-06-01

    Employing the annual herb Hemizonia luzulaefolia, native to nutrient limited grassland ecosystem in California, and a community of indigenous vesicular-arbuscular mycorrhizal (VAM) fungi, this study examined mycorrhizal response to interacting plant- and fungus-acquired resources. Plant carbon supply was manipulated through atmospheric carbon dioxide (CO[sub 2]) concentration, and substrate phosphorus (P) supply was varied in the nutrient solution. H. luzulaefolia responded strongly to VAM association, showing increased root and shoot biomass, greater leaf area, higher shoot P content and lower specific root length relative to non-mycorrhizal plants. Elevated (700 ppm) CO[sub 2] plants had lower mass, lower root:shoot ratios and slightly greater specific root length than ambient pCO[sub 2]-grown plants. VAM colonization of roots was stimulated by elevated CO[sub 2] early in the experiment. Low P plants showed greater leaf mass per area and lower shoot P concentration than plus-P plants. P effects on measures of VAM changed over time. While ambient pCO[sub 2]-grown plants responsed to added P with increased biomass, plants grown at elevated CO[sub 2] showed equivalent or lower biomass in plus-P treatments than in those with no added P. At the same time, ambient pCO[sub 2]-grown plants developed greater VAM colonization of roots in low P treatments, while at 700 ppm CO[sub 2]. VAM colonization was higher in plus-P treatments. It appears that atmospheric pCO[sub 2] affects the patterns of belowground allocation in H. luzulaefolia: ambient pCO[sub 2] plants direct carbon resources to VAM when P is low and to roots when P is available, while elevated CO[sub 2] plants maintain VAM colonization regardless of P environment and allocate to roots when P is low.

  12. Laboratory bioassay for assessing the effects of sludge supernatant on plant growth and vesicular-arbuscular mycorrhiza formation

    Energy Technology Data Exchange (ETDEWEB)

    Bohn, K.S.; Liberta, A.E.

    1982-12-01

    A laboratory bioassay is described for assessing the effects of sludge supernatant on juvenile corn growth and the ability of vesicular-arbuscular (VA) mycorrhizal fungi, indigenous to coal spoil, to form mycorrhizae. The bioassay demonstrated that application rates can be identified that have the potential to promote increased plant dry weight without suppressing the formation of VA mycorrhizae in a plant's root system.

  13. Influence of vesicular arbuscular mycorrhiza (VAM) and phosphate ...

    African Journals Online (AJOL)

    User

    2013-09-18

    Sep 18, 2013 ... Organic wastes and biofertilizers are alternate sour- ... consequence of regular application of chemical fertilizers. However, a large proportion of soluble inorganic phos- phate added to soil is rapidly fixed as insoluble forms.

  14. Factors influencing survival of vesicular-arbuscular mycorrhiza propagules during topsoil storage

    Energy Technology Data Exchange (ETDEWEB)

    Miller, R.M.; Carnes, B.A.; Moorman, T.B.

    1985-01-01

    The survival dynamics of vesicular-arbuscular mycorrhizal fungi were determined, (using a bioassay procedure) for soils stored from 0.5 to 6.0 years in topsoil stockpiles associated with a coal surface-mine in the western United States. Propagule mortality could best be related to in situ soil moisture potential using a piecewise regression model (R/sup 2/ = 0.57; P less than or equal to 0.001) with the breaking point occurring at -2 MPa. The addition of length of storage time was found to contribute significantly to the accuracy of the model (R/sup 2/ = 0.70; P less than or equal to 0.001). In addition, the piece-wise nature of the data suggested two separate populations of VAM fungi - those propagules found in soils with moisture potentials less than -2 MPa and those occurring in soils with moisture potentials greater than -2 MPa. Soil moisture and length of storage time had differing effects on each of these populations. When water potential was less than -2 MPa, moisture was an important predictor of inoculum (P < 0.001), while length of storage had little predictive capability (P = 0.17). However, when water potentials were greater than -2 MPa, the predictive importance of soil moisture (P = 0.86) and length of storage (P = 0.04) were reversed. The significance of these findings to topsoil replacement and subsequent plant community development are discussed. 28 references, 2 figures, 2 tables.

  15. Vesicular-arbuscular-/ecto-mycorrhiza succession in seedlings of. Eucalyptus spp.

    Directory of Open Access Journals (Sweden)

    Santos Vera Lúcia dos

    2001-01-01

    Full Text Available The occurrence of vesicular-arbuscular mycorrhizae (AM and ectomycorrhizae (ECM in the same root system was observed when species of Eucalyptus urophylla S.T. Blake, E. citriodora Hook f., E. grandis W. Hill ex Maiden, E. cloeziana F. Muell. and E. camaldulensis Dehnh were simultaneously inoculated with Glomus etunicatum Becker & Gederman and Pisolithus tinctorius (Per. Cocker & Couch, isolate Pt 90A. The succession between the two fungi was observed. In general ectomycorrhizal colonization increased followed by a decrease in AM. Pisolithus tinctorius was favored in simultaneous inoculation with G. etunicatum, and the positive effect of the simultaneous inoculation of both fungi in the percent colonization by the AM fungus occurred up to 60 days after inoculation. After 120 days, colonization of roots by G. etunicatum decreased in the presence of P. tinctorius. When inoculated simultaneously, the proportion of AM and ECM varied with evaluation time, while the combined percentage of mycorrhizal roots approached the maximum and remained more or less constant after 60 days, suggesting that there could be competition between the fungi for limiting substrate. The maximum percent mycorrhizal colonization varied with Eucalyptus species and the highest value was observed for E. camaldulensis, followed in order by E. citriodora, E. urophylla, E. grandis and E. cloeziana.

  16. Comparison of vesicular-arbuscular mycorrhizae in plants from disturbed and adjacent undisturbed regions of a coastal salt marsh in Clinton, Connecticut, USA

    Science.gov (United States)

    Cooke, John C.; Lefor, Michael W.

    1990-01-01

    Roots of salt marsh plant species Spartina alterniflora, S. patens, Distichlis spicata, and others were examined for the presence of vesicular-arbuscular mycorrhizal (VAM) fungi. Samples were taken from introduced planted material in a salt marsh restoration project and from native material in adjacent marsh areas along the Indian River, Clinton, Connecticut, USA. After ten years the replanted area still has sites devoid of vegetation. The salt marsh plants introduced there were devoid of VAM fungi, while high marsh species from the adjacent undisturbed region showed consistent infection, leading the authors to suggest that VAM fungal infection of planting stocks may be a factor in the success of marsh restoration.

  17. The Role of Teak Leaves (Tectona grandis), Rhizobium, and Vesicular-Arbuscular Mycorrhizae on Improving Soil Structure and Soil Nutrition

    Science.gov (United States)

    Yuliani; Rahayu, Y. S.

    2018-01-01

    Calcium is the largest mineral in calcareous soils. High levels of calcium carbonate lead to phosphate deposition. Nutrient deficiencies in calcareous soil (mainly Phosphate and Nitrogen) resulted only certain crops with a wide range of tolerances that can grow. Meanwhile, dynamics nutrient in calcareous soils also depend on the topography and decomposition of the litter in the growing vegetation. The purpose of this study was to describe the pattern of nutrient enhancement and soil-texture structures on calcareous soils after littering the teak leaves, Rhizobium and Vesicular Arbuscular Mycorrhiza. The research parameters were the concentration of N, P, K; C/N ratio, humid acid content, and soil structure, which measured at days 30, 60, and 85 of soil decomposition process. The results showed that at days 30, the texture and structure of the soil tend to be stable (porosity 31.2, DMR 1.93, moisture content 0.36, sandy clay) while at days 85 has been very stable (porosity 49.8; Water content 0.28, sandy clay). While C and N organic, N and K concentration at days 30 showed low value (C organic 1.03, N 0.12, K 0.49, C / N ratio 9). This condition is almost unchanged at days 85. While the P value shows very high value (60.53) at days 30 although after 60 days the P content showed a decrease.

  18. Interspecific plant association effects on vesicular-arbuscular mycorrhiza occurrence in Atriplex confertifolia

    Energy Technology Data Exchange (ETDEWEB)

    Miller, R.M.; Moorman, T.B.; Schmidt, S.K.

    1983-01-01

    Earlier studies with the shrub Atriplex confertifolia (Chenopodiaceae) suggested that the occurrence of mycotrophy was related to the community from which root samples were obtained; plants in disturbed areas were non-mycotrophic, while those growing in native areas possessed infection. Upon closer examination when neighbouring plants were studied, the level of mycorrhizal infection of Atriplex confertifolia was found to be related to its interspecific plant associations. When Atriplex confertifolia occurred solitarily, or in the presence of non-mycorrhizal A. gardneri, it was non-mycotrophic. However, when occurring near grasses or Artemisia spinescens, it possessed mycorrhiza infection. What appeared to be a community effect for the occurrence of mycorrhiza is nothing more than an association effect in which level of infection is related to the degree of mycorrhizal host plant cover. In disturbed communities little chance occurs for encountering a neighbouring mycorrhizal plant, while native plant communities are composed primarily of mycorrhizal counterparts. 22 references, 1 figure, 3 tables.

  19. Growth and Nutrient Uptake Responses of Kinnow to Vesicular Arbuscular Mycorrhizae

    OpenAIRE

    M.H. Shamshiri; K Usha; Bhupinder Singh

    2012-01-01

    In a field experiment, three-year-old Kinnow trees budded on Jatti Katti (C. jambhiri) rootstock were inoculated by three different arbuscular mycorrhiza (AM), Glomus manihotis (T1), Glomus mosseae (T2), and Gigaspora gigantia (T3), separately or in combination (T4). Microscopic assessment of AM colonization on Kinnow roots showed a relatively lower level of infection by different species when inoculated separately than when inoculaed together. Application of AM improved growth parameters lik...

  20. Vesicular-Arbuscular Mycorrhiza and Growth in Barley - Effects of Irradiation and Heating of Soil

    DEFF Research Database (Denmark)

    Jakobsen, Iver; Andersen, A. J.

    1982-01-01

    propagules. Mycorrhiza developed more slowly after inoculation in irradiated soils than in untreated soils. This could have been due to the small amounts of inoculum used, but the high concentrations of nutrients released by irradiation of the soil were probably of greater significance particularly......The influence of soil irradiation (0.25–4.0 Mrad) and soil heating on mycorrhizal survival, establishment and development after reinoculation, and on plant growth, was investigated. The lowest radiation dose applied, completely eliminated the infectivity of a soil with a high number of mycorrhizal...

  1. NUTRIENT TRANSFER IN VESICULAR-ARBUSCULAR MYCORRHIZAS: A NEW MODEL BASED ON THE DISTRIBUTION OF ATPases ON FUNGAL AND PLANT MEMBRANES

    Directory of Open Access Journals (Sweden)

    S.E. SMITH

    1995-01-01

    Full Text Available In this paper we review the membrane transport processes that are involved in the transfer of mineral nutrients and organic carbon between the symbiotic partners in mycorrhizas. In particular, we reassess the prevailing hypothesis that transfer in vesicular-arbuscular (VA mycorrhizas occurs simultaneously and bidirectionally across the same interface and that arbuscules are the main sites of transfer. Using cytochemical techniques, we and our collaborators have reexamined the distribution of ATPases in the arbuscular and intercellular hyphal interfaces in VA mycorrhizas formed between roots ofAllium cepa (onion and the fungus Glomus intraradices. The results showed that H +-ATPases have different localisation on plant and fungal membranes in arbuscular and hyphal interfaces (Gianinazzi-Pearson et al. 1991. While some arbuscular interfaces had H+-ATPase activity on both fungal and plant membranes, in most cases the fungal membrane lacked this activity. In contrast, the plasma membranes of intercellular hyphae always had H + -ATPase and the adjacent root cells did not. This suggests that the different interfaces in a VA mycorrhiza may have different functions. We propose that passive loss of P from the arbuscules is associated with active uptake by the energised (ATPase-bearing plant membrane and that passive loss of carbohydrate from the root cells is followed by active uptake by the intercellular hyphae. If this model is correct, then variations in "mycorrhizal efficiency" (i.e. the extent to which mycorrhizal plants grow better than non-mycorrhizal controls might be determined by differences in the numbers of active arbuscules as a proportion of the total fungal biomass within the root. As a first step towards investigating this possibility, we have developed methods for measuring the surface areas of arbuscular and hyphal interfaces in different fungus-host combinations, Glomus spp./ Allium porrum (leek. We have also measured fluxes of P from

  2. Effect of vesicular arbuscular mycorrhizal fungus on the ...

    African Journals Online (AJOL)

    The symbiotic association between certain plants and microorganisms plays an important role in soil fertilization, and improves their growth and mineral nutrition. The symbiotic association between vesicular arbuscular mycorrhizal (VAM) fungi and roots provides a significant contribution to plant nutrition and growth.

  3. The vesicular-arbuscular mycorrhizal symbiosis | Quilambo | African ...

    African Journals Online (AJOL)

    Vesicular-arbuscular mycorrhiza fungi are associated with the majority ot the terrestrial plants. Their function ranges from stress alleviation to bioremediation in soils polluted with heavy metals. However, our knowledge about this symbiosis is still limited. For the semi-arid tropics, where some african countries are located, ...

  4. Reduction of bacterial growth by a vesicular-arbuscular mycorrhizal fungus in the rhizosphere of cucumber (Cucumis sativus L.)

    DEFF Research Database (Denmark)

    Christensen, H.; Jakobsen, I.

    1993-01-01

    Cucumber was grown in a partially sterilized sand-soil mixture with the vesicular-arbuscular mycorrhizal (VAM) fungus Glomus fasciculatum or left uninoculated. Fresh soil extract was places in polyvinyl chloride tubes without propagules of mycorrhizal fungi. Root tips and root segments...

  5. Vesicular-arbuscular mycorrhiza in guayule

    Energy Technology Data Exchange (ETDEWEB)

    Bloss, H.E.

    1980-01-01

    There is renewed interest in the cultivation of guayule (Parthenium argentatum A. Gray) as a domestic source of natural rubber. Guayule roots from Texas were observed for the presence of mycorrihizae. A symbiont identified as Glomus fasciculatus has been isolated. (ACR)

  6. Soil lime level (pH) and VA-Mycorrhiza effects on growth responses of sweetgum seedlings

    Energy Technology Data Exchange (ETDEWEB)

    Davis, E.A.; Young, J.L.; Linderman, R.G.

    1983-01-01

    Sequential greenhouse experiments limed a strongly acid surface and subsurface horizons of phosphorus-deficient Jory clay loam with increments of calcium carbonate to attain a range in soil pH from 5.0 to 8.1. In the absence of vesicular-arbuscular mycorrhizae (VAM), neither the organic matter-rich surface nor the organic matter-poor subsurface horizon supported growth of sweetgum seedlings at any pH despite regular nutrient supplements. The effects of pH, VAM, and soil horizon on nutrient accumulation and plant nutrient concentrations were variable. Nitrogen and phosphorus concentrations were generally higher in the VAM than in control seedlings, which suggests that host plant should be matched with VAM species adapted to particular soil and climate conditions to obtain maximum benefit from a mycorrhizal association. 18 references, 2 figures, 3 tables.

  7. (VAM) and phosphate solubilizing bacteria (PSB)

    African Journals Online (AJOL)

    User

    2013-09-18

    Sep 18, 2013 ... potash mobilizing and plant promoting microorganisms. Vesicular arbuscular mycorrhizal (VAM) fungi improve plant growth through phosphorous nutrition. In addition to phosphorous, they also help in the uptake of other nutri- ent elements. Nutrient absorption by fungal symbionts is due to external hyphae ...

  8. Effect of fly ash on VAM formation and growth response of pulse crops infested with Glomus aggregatum in sterile soil

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, C.N.; Garampalli, H.R. [Gulbarga University, Gulbarga (India). Dept. of P.G. Studies and Research in Botany

    2002-07-01

    The effect of flyash amendment at 3 concentrations (10%, 20% and 30%) on the infectivity and efficacy of Glomus aggregatum was studied by conducting a pot culture experiment with sterile low fertile soil using pigeon pea (Cajanus cagan (L.) Millsp.) Cv. Maruti and Chick pea (Cicer ariteinum L.) Cv. Annigeri, the two pulse crop cultivars of this region. It is evident from the present investigation that the percent vesicular arbuscular mycorrhiza, VAM colonization in both the crops significantly decreased with the increase of flyash content in the soil. The formation of VAM fungal structures (vesicles and arbuscules) inside the host root was also found completely suppressed at higher concentrations of flyash. The effectiveness of G. aggregatum under the influence of flyash was found significantly affected as compared to control, when judged by the growth response of pigeon pea. However in chickpea VAM association could slightly increase the growth over its control. Flyash amendment alone also has shown positive influence on the growth of both the crops over their controls (without VAM association). This influence of flyash amendment together with the usefulness of VAM fungi, as bioremediation agents can be exploited suitably in reclamation of waste lands and soils overburdened with flyash. 40 refs., 3 tabs.

  9. The Physiological Response of Soybean Genotypes to VAM Inoculation on Selected Drought Stress Levels

    Directory of Open Access Journals (Sweden)

    HAPSOH

    2006-06-01

    Full Text Available Present research was aimed to study physiological changes of soybean which were inoculated with vesicular arbuscular mycorrhizal fungi (VAM. Glomus etunicatum was exposed to moderate and severe drought condition. Symbiotic association with VAM improved adaptability as it was shown by the increasing leaf proline content. The MLG 3474 and Sindoro are the more tolerant genotypes while the responses of plant to VAM on improving the adaptability to drought were larger on Lokon.

  10. Arbuscules of vesicular-arbuscular mycorrhizal fungi inhabit an acidic compartment within plant roots.

    Science.gov (United States)

    Guttenberger, M

    2000-08-01

    The most widespread type of mycorrhiza is the so-called vesicular-arbuscular mycorrhiza. In this endomycorrhiza, fungal hyphae penetrate plant cell walls in the root cortex. There they form densely branched arbuscules. Fungus and plant plasma membrane are separated by a common interfacial apoplast. The pH of the compartment between the symbionts is of pivotal importance for nutrient transfer. Histochemical experiments were conducted to check for an acidic nature of the interface in the model system Glomus versiforme (Karst.) Berch-Allium porrum L. Two chemically different acidotropic dyes (neutral red and LysoSensor Green DND-189) stained the arbuscules intensely. The staining of arbuscules could be eliminated by addition of the protonophore carbonylcyanide m-chlorophenylhydrazone (CCCP) or treatments leading to membrane rupture. Therefore, the staining of the arbuscules was based on the ion-trap mechanism, which indicates acidic, membrane-bound compartments. Microscopic examination of stained arbuscules at high optical resolution revealed a peripheral accumulation of the dye. Since plasmolysis rapidly destained the arbuscules, it is concluded that the dyes accumulate in the arbuscular interface, indicating the highly acidic nature of this compartment. The findings are discussed with respect to their relevance for the nutrient transfer in mycorrhizas. In addition, evidence for a discontinuity in the arbuscular interface between the stem and the branches of the arbuscule is given.

  11. Vesicular-Arbuscular Mycorrhiza in Field-Grown Crops

    DEFF Research Database (Denmark)

    Jakobsen, Iver

    1983-01-01

    The effect of inoculation with vesicular–arbuscular mycorrhizal fungi on the growth of barley in the field was studied at two levels of soil P on plots fumigated with methyl bromide. During the vegetative phase, growth and P uptake was influenced only by soil P; P uptake in the period from earing...

  12. Mycorrhiza and crop production

    Energy Technology Data Exchange (ETDEWEB)

    Hayman, D.S.

    1980-10-09

    This article describes recent research with vesicular-arbuscular mycorrhiza, a symbiotic fungus-root association. The suggestion that the symbiotic association may be harnessed to achieve more economical use of phosphate fertilizers is discussed and the results from various test crops are given.

  13. Effect of solarization and vesicular arbuscular mychorrizal on weed ...

    African Journals Online (AJOL)

    USER

    2010-06-14

    Jun 14, 2010 ... To determine VAM before testing in laboratory, VAM dutied like a bridge from donor lettuce to receiver wild mustard (Sinapsis arvensis L.) as observed in the experiment because mustrad has no symbiosis life with this fungus. Also the laboratory findings supported this; the number of spores, number of VAM.

  14. Effect of solarization and vesicular arbuscular mychorrizal on weed ...

    African Journals Online (AJOL)

    USER

    2010-06-14

    Jun 14, 2010 ... determine VAM before testing in laboratory, VAM dutied like a bridge from donor lettuce to receiver wild mustard (Sinapsis ... Also the laboratory findings supported this; the number of spores, number of VAM infected and infection rate ..... Technics and usages of Mycorrhizal spor in agricultura. Cukurova.

  15. Occurrence and succession of mycorrhizas in Alnus incana

    Energy Technology Data Exchange (ETDEWEB)

    Arveby, A.S. [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Section of Forest Ecophysiology; Granhall, U. [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Microbiology

    1998-12-31

    The occurrence of different mycorrhizas of the grey alder, Alnus incana (L.) Moench., in Sweden was investigated. Root sampling was carried out in planted and natural grey alder stands, representing different soil types, geographical sites, and plant ages. Mycorrhizal infection of roots was found to be frequent at all investigated sites, except for some planted peat bogs, where alders do not occur naturally. At the latter sites, mycorrhizal infection was less frequent and consisted only of ectomycorrhizas. Young trees here were non-mycorrhizal. At all other sites vesicular-arbuscular mycorrhiza (VAM) was found to be the almost exclusive type of mycorrhiza in first-year seedlings. In trees older than one year ectomycorrhiza was the dominating type. In the planted stands up to five years of age no fruitbodies of ectomycorrhizal fungi were found. In such stands the ectomycorrhizas generally had thin, translucent mantles and could be observed only by microscopic examination. In one old plantation (27 years) and in the natural stands sporocarps of several specific `alder fungi` were found. Here, the mycorrhizal root tips had thick, mostly whitish mantles. The Hartig net was in all cases confined to penetration between epidermal cells. Soil collected from one alder site and two non-alder biotopes readily infected grey alder seedlings with Frankia and VAM fungi whereas a peat soil failed to infect seedlings with any symbiont. In vitro inoculation of nodulated seedlings with Glomus mossae (Nicol. and Gerd.) Gerdemann and Trappe resulted in VAM-infection. Simultaneous syntheses with isolates of alder-specific, and other, ectomycorrhizal fungi, using three different methods, failed. On the basis of these results an endomycorrhizal-ectomycorrhizal succession after the first growth season in Alnus incana is concluded. A subsequent succession of ectomycorrhizal species from early-stage to late-stage ones is discussed 58 refs, 3 figs, 2 tabs

  16. Effect of solarization and vesicular arbuscular mychorrizal on weed ...

    African Journals Online (AJOL)

    mustard (Sinapsis arvensis L.) as observed in the experiment because mustrad has no symbiosis life with this fungus. Also the laboratory findings supported this; the number of spores, number of VAM infected and infection rate were higher both in main parcel of solarized and in the subplot parcel planted with VAM ...

  17. Role of VAM on growth and phosphorus nutrition of maize with low soluble phosphate fertilization

    OpenAIRE

    Amitava Rakshit; Pratapbhanu S Bhadoria

    2010-01-01

    The effect of vesicular arbuscular mycorrhizal (VAM) infection on growth and P nutrition in Maize (Zea mays, cv.DDH hybrid) were assessed in Oxisol pot experiment. Maize was grown inoculated with spores of VAM fungi Glomus mosseae or non-inoculated. Low soluble ferrous phosphate (FePO4.4H2O) was added to the mycorrhized and non-micrrohized maized. The dry weight of mycorrhized plants with added phosphate (P) were higher than in mycorrhized plants without added P or non-mycorrhized plants with...

  18. Influence of Al and the heavy metals Fe, Mn, Zn, Cu, Pb, and Cd on development and efficacy of vesicular-arbuscular mycorrhiza in tropical and subtropical plants. Einfluss von Al und den Schwermetallen Fe, Mn, Zn, Cu, Pb und Cd auf die Effizienz der VA-Mykorrhiza bei tropischen und subtropischen Pflanzen

    Energy Technology Data Exchange (ETDEWEB)

    Fabig, B.

    1982-07-08

    In greenhouse experiments the influence of Al and the heavy metals Fe, Mn, Zn, Cu, Pb, and Cd on the efficacy of VA-mycorrhizal fungi was tested with special regard to several soil pH levels and soil water regimes in different combinations. The most important results were: The inoculation led to a significantly better growth of all test plants in the presence of Al, Fe, Mn, Zn, Cu, Pb, and Cd up to a specific amount of the soil-applied element; beyond this specific limit the efficacy of the mycorrhiza was more or less inhibited depending on the element. In correlation with the growth, the nearly always better P uptake of the inoculated plants was impaired only by the highest toxic amounts of the elements. In comparison with the uninoculated plants, all the inoculated plants showed higher P and Pb concentrations. The mycorrhizal plants generally had significantly higher concentrations of the elements Al, Mn, Zn, Cu, and Cd in the roots than the uninoculated plants. Generally even toxic levels of Fe in the soil did not lead to higher Fe concentrations in the plants. Even the highest amounts of Al, Fe, Mn, Zn, and Cu did not cause microscopically visible injuries to the development of the mycorrhiza and did not impede the infection. Only the toxic levels of Pb led to a decrease of the infection rate of about 50%. Pb and Cd were the reason for morphological changes of the different developmental phases of the fungus. High amounts of Pb induced an increased formation of vesicles. The highest amounts of Cd were accompanied by the crowded occurrence of arbuscules.

  19. Vesicular-arbuscular mycorrhizae established with Glomus fasciculatus spores isolated from the feces of cricetine mice

    Science.gov (United States)

    Frederick M. Rothwell; Coleman Holt

    1978-01-01

    Cricetine mice were trapped on two revegetated surface-mined areas - one with a freshly seeded grass-legume cover and one with an early successional grass-forb cover. Chlamydospores of Glomus fasciculatus isolated from the feces of these animals produced representative endomycorrhizae with corn under greenhouse conditions.

  20. EFFECTS OF CORN CULTIVAR-TILLAGE SYSTEM COMBINATION ON VESICULAR ARBUSCULAR MYCORRHIZAE

    Directory of Open Access Journals (Sweden)

    Joko Prasetyo .

    2011-10-01

    Full Text Available Pengaruh kombinasi  varietas jagung dan sistem olah tanah terhadap mikorisa vesikular arbuskular.  Penelitian telah dilakukan untuk mengevaluasi pengaruh kombinasi sistem olah tanah dan varietas terhadap  populasi mikorisa vesikular arbuskular. Penelitian juga ditujukan untuk mengetahui pengaruh kombinasi varietas jagung dan sistem olah tanah terhadap infeksi mikorisa vesicular arbuskular. Penelitian terdiri atas enam perlakuan yang disusun dalam rancangan acak kelompok. Perlakuan tersebut adalah varietas RR yang ditanam pada sistem olah tanah konservasi  (RRCT, varietas C7 yang ditanam pada sistem olah tanah konservasi (C7CT, varietas Bisma ditanam pada sistem olah tanah konservasi (BCT, varietas RR ditanam pada sistem olah tanah sempurna (RRFT, varietas C7 yang ditanam pada sistem olah tanah sempurna (C7FT, dan varietas Bisma ditanam pada sistem olah tanah sempurna (BFT. Hasil penelitian pada sistem olah tanah konservasi  menunjukkan bahwa varietas RR dan C7 secara nyata dapat menurunkan infeksi mikorisa dibandingkan dengan varietas Bisma. Hasil penelitian juga menunjukkan bahwa pada varietas RR dan C7, olah tanah konservasi secara nyata menurunkan infeksi mikorisa dibandingkan dengan sistem olah tanah sempurna.

  1. Increasing Growth and Yield of Upland Rice by Application of Vesicular Arbuscular Mycorrhizae and Potassium Fertilizer

    Directory of Open Access Journals (Sweden)

    Dedi Natawijaya

    2012-01-01

    Full Text Available Field experiment with a split plot design has been carried out in order to assess the growth characteristics andyields, and effectiveness of MVA upland rice which were given potassium fertilizer in two growing seasons. MVAinoculation consisted of three treatments (without MVA, Glomus sp. and Gigaspora sp. while potassium fertilizerconsisted of five levels (0, 12.5, 25, 37.5, and 50 kg ha-1 K. The results showed that plant growth variable which wasinoculated by MVA at any levels of K fertilizer was higher in the dry season than that in the wet season, whereas theopposite occurred for net assimilation rate. Potassium content of leaf tissue, shoot/root ratio, and grain weight perhill was determined and mutually dependent on genus MVA, dosages of K fertilizer, and growing season. Harvestindex and grain dry weight per hill were influenced by the growing season and the genus MVA but the effect did notdepend on each other. At all dosages of K fertilizer and any MVA genera, Gigaspora sp. inoculation was better thanthat of Glomus sp. Dry weight of grains per hill was affected by the contribution of grain content per hill, weight of1000 grains and number of productive seedlings per hill. The optimum dosage of K fertilizer in the dry season was32.4 kg ha-1 K with grain yield 3.12 Mg ha-1 for inoculation of Gigaspora sp., whereas the optimum dosage in the wetseason was 34.2 kg ha-1 K for the treatment Glomus sp. inoculation with Gigaspora sp. in the wet season did notreach dosages of optimum K fertilizer.

  2. Effects of vesicular-arbuscular mycorrhizae and seed source on nursery-grown black walnut seedlings

    Science.gov (United States)

    B. L. Brookshire; H. E. Garrett; T. L. Robison

    2003-01-01

    A nursery study was established in Missouri to evaluate the effects of endomycorrhizal inoculation and seed source on the growth of black walnut seedlings. Inoculation, in general, resulted in seedlings with significantly larger sturdiness quotients. Glomus intraradicies was found to produce larger seedlings than Glomus etunicatus...

  3. Mycorrhizae

    Science.gov (United States)

    Martin Jurgensen; Dana Richter; Carl C. Trettin; Mary Davis

    2000-01-01

    Mycorrhizae, a mutual partnership between certain soil fungi and fine root tips, contribute to tree growth and vigor by increasing both water and nutrient uptake, especially nitrogen (N) and phosphorus (P). The fungal hyphae increase root surface contact with the soil, while the fungi are supplied with a reliable source of carbon (Allen 1991, George and Marschner 1995...

  4. Role of VAM on growth and phosphorus nutrition of maize with low soluble phosphate fertilization

    Directory of Open Access Journals (Sweden)

    Rakshit Amitava

    2010-03-01

    Full Text Available The effect of vesicular arbuscular mycorrhizal (VAM infection on growth and P nutrition in Maize (Zea mays, cv.DDH hybrid were assessed in Oxisol pot experiment. Maize was grown inoculated with spores of VAM fungi Glomus mosseae or non-inoculated. Low soluble ferrous phosphate (FePO4.4H2O was added to the mycorrhized and non-micrrohized maized. The dry weight of mycorrhized plants with added phosphate (P were higher than in mycorrhized plants without added P or non-mycorrhized plants with added P. The amount of P in the soil samples from pots with mycorrhizal plants fertilized with P was evidently smaller than those in samples also fertilized non-mycorrhizal plants. The percentage of P was higher in tissues of fertilized mycorrhial plants than in those mycorrihzed plants without or nonmycorrhized plants with added low-soluble P. These results indicated that plants in VAM symbiosis mobilize P better from low-soluble P than non-mycorrhized plants.

  5. Role of VAM on growth and phosphorus nutrition of maize with low soluble phosphate fertilization

    Directory of Open Access Journals (Sweden)

    Amitava Rakshit

    2010-01-01

    Full Text Available The effect of vesicular arbuscular mycorrhizal (VAM infection on growth and P nutrition in Maize (Zea mays, cv.DDH hybrid were assessed in Oxisol pot experiment. Maize was grown inoculated with spores of VAM fungi Glomus mosseae or non-inoculated. Low soluble ferrous phosphate (FePO4.4H2O was added to the mycorrhized and non-micrrohized maized. The dry weight of mycorrhized plants with added phosphate (P were higher than in mycorrhized plants without added P or non-mycorrhized plants with added P. The amount of P in the soil samples from pots with mycorrhizal plants fertilized with P was evidently smaller than those in samples also fertilized non-mycorrhizal plants. The percentage of P was higher in tissues of fertilized mycorrhial plants than in those mycorrihzed plants without or nonmycorrhized plants with added low-soluble P. These results indicated that plants in VAM symbiosis mobilize P better from low-soluble P than non-mycorrhized plants.

  6. Verification Account Management System (VAMS)

    Data.gov (United States)

    Social Security Administration — The Verification Account Management System (VAMS) is the centralized location for maintaining SSA's verification and data exchange accounts. VAMS account management...

  7. Role of VAM on growth and phosphorus nutrition of maize with low soluble phosphate fertilization Efecto de la infestación con micorrizas vesiculo arbusculares (VAM en plantas de Zea mays fertilizadas con dosis bajas de fósforo

    Directory of Open Access Journals (Sweden)

    Amitava Rakshit

    2010-01-01

    Full Text Available The effect of vesicular arbuscular mycorrhizal (VAM infection on growth and P nutrition in Maize (Zea mays, cv.DDH hybrid were assessed in Oxisol pot experiment. Maize was grown inoculated with spores of VAM fungi Glomus mosseae or non-inoculated. Low soluble ferrous phosphate (FePO4.4H2O was added to the mycorrhized and non-micrrohized maized. The dry weight of mycorrhized plants with added phosphate (P were higher than in mycorrhized plants without added P or non-mycorrhized plants with added P. The amount of P in the soil samples from pots with mycorrhizal plants fertilized with P was evidently smaller than those in samples also fertilized non-mycorrhizal plants. The percentage of P was higher in tissues of fertilized mycorrhial plants than in those mycorrihzed plants without or nonmycorrhized plants with added low-soluble P. These results indicated that plants in VAM symbiosis mobilize P better from low-soluble P than non-mycorrhized plants.En condiciones de casa de malla se evaluó el efecto de la infestación con micorrizas vesículo arbusculares (VAM en la asimilación de P por plantas de maíz (Zea mays, cv.DDH hybrid cultivadas en un Oxisol. Como micorriza se utilizó el hongo Glomus mosseae. En ambos tratamientos (con micorriza y sin ella se aplicó fosfato ferroso (FePO4.4H2O. La producción de MS de maíz fue mayor cuando se aplicaron el hongo + la fuente de P. La cantidad de P en el suelo con este tratamiento fue menor que en el suelo fertilizado pero sin aplicación del hongo. En las hojas de las plantas las mayores concentraciones de P se observaron igualmente en el tratamiento micorriza + aplicación de fertilizante.

  8. Fungos micorrízicos-arbusculares no desenvolvimento de mudas de helicônia e gérbera micropropagadas Application of arbuscular mycorrhiza to micropropagated heliconia and gerbera plants during acclimatization period

    Directory of Open Access Journals (Sweden)

    Aurora Yoshiko Sato

    1999-03-01

    Full Text Available Plântulas micropropagadas de helicônia (Heliconia sp gérbera (Gerbera sp de vaso, foram aclimatadas em substrato (torta de filtro 50%, solo 30% e areia 20%, inoculado com três espécies de fungo micorrízico (Glomus clarum Nicolson. & Schenck, Glomus etunicatum Becker & Gerdemann e Gigaspora margarita Becker & Hall e uma mistura destas espécies (inóculo múltiplo. As avaliações quanto ao desenvolvimento da parte aérea e do sistema radicular e porcentagem de colonização, foram feitas aos 60 dias para gérbera e aos 90 dias para helicônia, após transplante. As duas espécies comportaram-se de modo diferente em resposta à micorrização. Glomus etunicatum não colonizou bem nenhuma das duas espécies estudadas. Apesar da elevada colonização, a helicônia não se beneficiou da inoculação, enquanto que a gérbera beneficiou-se da inoculação com G. clarum, G. etunicatum e do inóculo misto.Heliconia (Heliconia sp. and pot gerbera plantlets (Gerbera sp. obtained by in vitro micropropagation on Murashige and Skoog (MS medium were inoculated with 3 vesicular arbuscular mycorrhiza (VAM species and a mixture of three species. A control treatment without inoculation was also included. The plantlets were acclimated in a mixture of soil 30%, sand 20% and "torta de filtro" 50%. The fungal species were Glomus clarum, Glomus etunicatum and Gigaspora margarita. At 60 days for gerbera and 90 days for heliconia after the inoculation, fresh and dry matter of the aerial and root parts were determined, and the percentage of mycorrhizal colonization of the roots was obtained. Both species behaved different to mycorrhization. Glomus etunicatum did not show to be effective in colonization of heliconia and gerbera. Colonization was high, but heliconia did not benefit from this inoculation, however Gerbera was benefited by G. clarum, G. etunicatum and mixture inoculation.

  9. Stomatal Conductance, Plant Species Distribution, and an Exploration of Rhizosphere Microbes and Mycorrhizae at a Deliberately Leakimg Experimental Carbon Sequestration Field (ZERT)

    Science.gov (United States)

    Sharma, B.; Apple, M. E.; Morales, S.; Zhou, X.; Holben, B.; Olson, J.; Prince, J.; Dobeck, L.; Cunningham, A. B.; Spangler, L.

    2010-12-01

    One measure to reduce atmospheric CO2 is to sequester it in deep geological formations. Rapid surface detection of any CO2 leakage is crucial. CO2 leakage rapidly affects vegetation above sequestration fields. Plant responses to high CO2 are valuable tools in surface detection of leaking CO2. The Zero Emission Research Technology (ZERT) site in Bozeman, MT is an experimental field for surface detection of CO2 where 0.15 ton/day of CO2 was released (7/19- 8/15/2010) from a 100m horizontal injection well, HIW, 1.5 m underground with deliberate leaks of CO2 at intervals, and from a vertical injector, VI, (6/3-6/24/2010). The vegetation includes Taraxacum officinale (Dandelion), Dactylis glomerata (Orchard Grass), and other herbaceous plants. We collected soil and roots 1, 3 and 5 m from the VI to determine the responses of mycorrhizal fungi and rhizosphere microbes to high CO2. Mycorrhizal fungi obtain C from root exudates, increase N and P availability, and reduce desiccation, while prokaryotic rhizosphere microbes fix atmospheric N and will be examined for abundance and expression of carbon and nitrogen cycling genes. We are quantifying mycorrhizal colonization and the proportion of spores, hyphae, and arbuscules in vesicular-arbuscular mycorrhizae (VAM) in cleared and stained roots. Stomatal conductance is an important measure of CO2 uptake and water loss via transpiration. We used a porometer (5-40°C, 0-90% RH, Decagon) to measure stomatal conductivity in dandelion and orchard grass at 1, 3, and 5 m from the VI and along a transect perpendicular to the HIW. Dandelion conductance was highest close to the VI and almost consistently higher close to hot spots (circular regions with maximum CO2 and leaf dieback) at the HIW, with 23.2 mmol/m2/s proximal to the hot spot, and 10.8 mmol/m2/s distally. Average conductance in grass (50.3 mmol/m2/s) was higher than in dandelion, but grass did not have high conductance near hot spots. Stomata generally close at elevated CO2

  10. Fungsi Bangunan Dokwi Vam dan Kembu Vam Bagi Suku Yali dalam Novel Penguasa-penguasa Bumi Karya Don Richardson

    Directory of Open Access Journals (Sweden)

    Ummu Fatimah Ria Lestari

    2016-04-01

    Full Text Available This study discusses the function of the building of Dokwi Vam and Kembu Vam contained in the novel-Sovereign Ruler of the Earth works Don Richardson. In general, this novel tells the story of the life of Stan Dale and Yali tribe. Stan Dale is a missionary who served in Papua. He struggled to introduce Christianity to the Yali tribe. This study uses the description of the technical literature. This research resulted in a description of the function of the building of Dokwi Vam and Kembu Vam contained in the novel Lord of-Ruler of the Earth works Don Richardson. Dokwi Vam used as a museum (where the old stuff to worship as they still follow animism, while the Kembu Vam serves as a temple / animism worship in Yali tribe. Penelitian ini membahas tentang fungsi bangunan Dokwi Vam dan Kembu Vam yang terdapat dalam novel Penguasa-Penguasa Bumi karya Don Richardson. Secara umum, novel ini bercerita tentang kehidupan Stan Dale dan suku Yali. Stan Dale adalah seorang missionaris yang melayani di Tanah Papua. Ia berjuang untuk memperkenalkan agama Nasrani kepada suku Yali. Penelitian ini menggunakan metode deskripsi dengan teknik studi pustaka. Penelitian ini menghasilkan deskripsi tentang fungsi bangunan Dokwi Vam dan Kembu Vam yang terdapat dalam novel Penguasa-Penguasa Bumi karya Don Richardson. Dokwi Vam digunakan sebagai museum (tempat barang-barang kuno untuk penyembahan karena mereka masih menganut kepercayaan animisme, sedangkan Kembu Vam berfungsi sebagai rumah peribadatan/penyembahan dalam kepercayaan animisme suku Yali.

  11. Geurproblematiek VAM Wijster : Beoordeling geuraspecten vergunningaanvraag voor gesloten GFT compostering en biologische slibdroging VAM-Wijster

    NARCIS (Netherlands)

    Posthumus, Willem; Mulder, Henk

    1998-01-01

    Dit rapport behandelt de geuremissie van het VAM-complex in Wijster. Het gaat vooral in op de geuraspecten in de uitbreidingsvergunning voor de gesloten compostering (GECO 400) en de vergunning voor de geplande biologische slibdroger (1). Tevens wordt aandacht besteed aan het algemene stankbeleid in

  12. Aquatic Plant Control Research Program: The Rhizosphere Microbiology of Rooted Aquatic Plants.

    Science.gov (United States)

    1988-04-01

    540-553. Bagyaraj, C. J., A. Manjunath, and R. B. Patil. 1979. Occurrence of vesicular- arbuscular mycorrhizas in some tropical aquatic plants...39-45. Chaubal, R., G. D. Charma, and R. R. Mishra. 1982. Vesicular- arbuscular mycorrhiza in subtropical aquatic and marshy plant communities...11A:29-35. Clayton, J. S. and D. J. Bagyaraj. 1984. Vesicular- arbuscular mycorrhizas in submerged aquatic plants of New Zealand. Aquatic Botany. 19:251

  13. Soil microbial-legume interacts in heavy metal contaminated at Palmerton, PA

    Energy Technology Data Exchange (ETDEWEB)

    Angle, J.S.; Spiro, M.A.; Heggo, A.M.; El-Kherbawy, M.; Chaney, R.L.

    1988-01-01

    The interaction between soil pH, vesicular-arbuscular mycorrhiza (VAM) and heavy metal uptake into soybeans (Glycine max) and alfalfa (Medicago sativa) was studied in the heavy metal stressed soils of Palmerton, PA. The dry weight of soybeans grown in soil with an available Zn concentration of 132 ug/g soil was 2.0 g/plant as compared to 0.13 g/plant for soybeans grown in soil containing 862 ug Zn/g soil. In the same soils, the foliar uptake of Zn was increased from 186 to 1020 ug Zn/g tissue. When VAM were inoculated into the soil with a high Zn content, the foliar Zn content was reduced from 968 to 780 ug/g tissue. Similar observations were noted for Cd and Mn. When, however, the soil metal concentration was low, VAM significantly increased heavy metal uptake. Vesicular-arbuscular mycorrhiza increased Zn uptake from 201 to 251 ug/g. Similar results were observed when the pH of a single soil was altered. Metal uptake, as affected by VAM, was generally decreased from soils with a low pH (6.0). At a soil pH of 6.7 and 7.2, VAM increased foliar heavy metal uptake. Both VAM colonization and plant growth were also increased by increasing soil pH. At a pH of 6.0, VAM colonization and plant growth were 15.5% and 0.37 g/10 alfalfa plants, respectively. At a pH of 7.2, VAM colonization was rated at 32.0% while plant growth of 0.76 g/10 plants was noted.

  14. Dipterocarpaceae : Mycorrhizae and regeneration

    NARCIS (Netherlands)

    Smits, W.T.M.

    1994-01-01

    Research on mycorrhizae of Dipterocarpaccae is described, involving inventories of both mycorrhizae and sporocarps in natural forest and experimental work in nurseries, green houses, laboratories and gnotobiotic systems. An assessment is made of dipterocarp mycorrhizal specificity and a

  15. An Introduction to Mycorrhizae.

    Science.gov (United States)

    Janerette, Carol A.

    1991-01-01

    The author describes relationships between the fungi called mycorrhizae and plants. Describes the classes of mycorrhizae and the importance of such fungi in plant growth. Presents clear micrographs of the fungi and their interactions with plant root cells. Provides technological applications of mycorrhizae in agriculture and discusses problems…

  16. Effets de l'inoculation de cinq espèces de Glomus sur la croissance et la nodulation en pépinière de Racosperma auriculiforme en République Démocratique du Congo

    Directory of Open Access Journals (Sweden)

    Bulakali, B.

    2000-01-01

    Full Text Available Effects of Inoculation with Five Glomus Species on Racosperma auriculiforme Growth and Nodulation in a Nursery in the Democratie Republic of the Congo. Racosperma auriculiforme has been inoculated in a nursery with five exotic vesicular - arbuscular mycorrhiza (VAM species. Among them, Glomus clarum revealed to be performant. Compared to the uninoculated control and others endomycorhizal species, it has stimulated significantly (P <0, 05 the plant height and the plant dry weight of shoot, root and total just as the plant stem diameter. Its utilization in the mycorhizogene replanting of the Kinzono grassy savanna is to be envisaged.

  17. United States Air Force Graduate Student Research Program for 1990. Program Management Report

    Science.gov (United States)

    1992-06-05

    Vesicular- Arbuscular Mycorrhizae 114 Volume IV 145 Mathematical Modeling and Decision-Making Dr. Miguel Medina for Air Force Contaminant Migration...HEALTH LABORATORY ABSTRACTS 273 An Assay to Determine the Phytotoxic Effects of Jet Fuel: Effects on Vesicular- Arbuscular Mycorrhizae by David W. Buckalew...aboveground parameters (i.e., shoot length and shoot wet and dry weights), belowground measures of total root length and percent vesicular- arbuscular

  18. United States Air Force Summer Faculty Research Program for 1990. Program Management Report

    Science.gov (United States)

    1991-06-05

    Laboratory 144 An Assay to Determine the Phytotoxic Effects Dr. David Buckalew of Jet Fuel: Effects on Vesicular- Arbuscular Mycorrhizae 114 Volume IV...Fuel: Effects on Vesicular- Arbuscular Mycorrhizae by David W. Buckalew ABSTRACT A new protocol is presented for using plants as analytical tools to...measures of total root length and percent vesicular- arbuscular mycorrhizal colonization are recorded within a common test grass. A brief discussion of

  19. Mycorrhizae of poplars

    Science.gov (United States)

    R. C. Schultz; J. G. Isebrands; P. P. Kormanik

    1983-01-01

    Poplar hybrids, being screened for short-rotation intensive culture, can form ecto-, endo-, or ectendo-mycorrhizae or may be autotrophic. Different sections of the genus Populus tend to be selective in the type of mycorrhizae formed. Knowledge of which types are formed influences the kinds of propagule production, site preparation, and herbicide...

  20. SIMULACIJE ZAPLETOV ANESTEZIJSKEGA APARATA V OKOLJU VAM (VIRTUAL ANESTHESIA MACHINE)

    OpenAIRE

    Jordan, Mirko

    2012-01-01

    Simulacija je postala sestavni del tako dodiplomskega, podiplomskega študija ter nadaljevanja izobraževanja v zdravstvu. V zadnjih letih so bile uvedene zlasti računalniško podprte simulacije, ki se zdaj že na široko uporabljajo. Ena od teh simulacij na spletu je simulacija anestezijskega aparata, medicinskih procesov in opreme, imenovana VAM simulacija. V tem diplomskem delu smo preučili navodila za VAM simulacije in nekaj osnov o delovanju anestezijskega aparata. Opisali smo tri simulacije...

  1. Validation and testing of the VAM2D computer code

    Energy Technology Data Exchange (ETDEWEB)

    Kool, J.B.; Wu, Y.S. (HydroGeoLogic, Inc., Herndon, VA (United States))

    1991-10-01

    This document describes two modeling studies conducted by HydroGeoLogic, Inc. for the US NRC under contract no. NRC-04089-090, entitled, Validation and Testing of the VAM2D Computer Code.'' VAM2D is a two-dimensional, variably saturated flow and transport code, with applications for performance assessment of nuclear waste disposal. The computer code itself is documented in a separate NUREG document (NUREG/CR-5352, 1989). The studies presented in this report involve application of the VAM2D code to two diverse subsurface modeling problems. The first one involves modeling of infiltration and redistribution of water and solutes in an initially dry, heterogeneous field soil. This application involves detailed modeling over a relatively short, 9-month time period. The second problem pertains to the application of VAM2D to the modeling of a waste disposal facility in a fractured clay, over much larger space and time scales and with particular emphasis on the applicability and reliability of using equivalent porous medium approach for simulating flow and transport in fractured geologic media. Reflecting the separate and distinct nature of the two problems studied, this report is organized in two separate parts. 61 refs., 31 figs., 9 tabs.

  2. Combustion of refuse-derived fuels in the GAVI-VAM system at Wijster; Verbrennung von RDF - Ersterfahrungen aus der GAVI-VAM (Wijster)

    Energy Technology Data Exchange (ETDEWEB)

    Wandschneider, J.; Warnek, J.; Klitzbe, H.J.

    1997-12-31

    The GAVI-VAM system consists of a sorting stage followed by a RDF combustion plant. The two parts are directly connected by an RDF bunker (24 h). The contribution presents a detailed description of the plant. (orig./AKF)

  3. Evolution of mycorrhiza systems

    Science.gov (United States)

    Cairney, J. W. G.

    Most terrestrial plants live in mutualistic symbiosis with root-infecting mycorrhizal fungi. Fossil records and molecular clock dating suggest that all extant land plants have arisen from an ancestral arbuscular mycorrhizal condition. Arbuscular mycorrhizas evolved concurrently with the first colonisation of land by plants some 450-500 million years ago and persist in most extant plant taxa. Ectomycorrhizas (about 200million years ago) and ericoid mycorrhizas (about 100million years ago) evolved subsequently as the organic matter content of some ancient soils increased and sclerophyllous vegetation arose as a response to nutrient-poor soils respectively. Mycorrhizal associations appear to be the result of relatively diffuse coevolutionary processes. While early events in the evolution of mycorrhizal symbioses may have involved reciprocal genetic changes in ancestral plants and free-living fungi, available evidence points largely to ongoing parallel evolution of the partners in response to environmental change.

  4. Combustion of high-rank light fraction. First experiences with GAVI/VAM; Verbrennung von heizwertreicher Leichtfraktion. Erste Erfahrungen aus der GAVI-VAM (Wijster)

    Energy Technology Data Exchange (ETDEWEB)

    Wandschneider, J. [Goepfert, Reimer und Partner Ingenieurgesellschaft mbH, Hamburg (Germany)

    1998-09-01

    GAVI/VAM consists of a sorting plant which is topped by an RDF combustion plant. These two plant components are directly linked with each other via an RDF bunker (24 h). The present contribution addresses the main components of the combustion plant individually and points out its special features as compared with crude waste combustion. [Deutsch] Die GAVI/VAM besteht aus einer Sortieranlage mit nachgeschalteter RDF-Verbrennungsanlage, beide Anlagenteile sind durch einen RDF-Bunker (24 h) unmittelbar miteinander verbunden. Nachfolgend werden die wesentlichen Komponenten der Verbrennungsanlage einzeln angesprochen und die Besonderheiten im Vergleich zur Rohmuellverbrennung dargestellt. (orig./SR)

  5. Does ozone exposure alter growth and carbon allocation of mycorrhizal plants

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, L.C.; Gamon, J.A. (California State Univ., Los Angeles, CA (United States)); Andersen, C.P. (Environmental Protection Agency, Corvallis, OR (United States))

    1994-06-01

    Ozone is known to adversely affect plant growth. However, it is less clear how ozone affects belowground processes. This study tests the hypothesis that ozone alters growth and carbon allocation of vesicular arbuscular mycorrhizal (VAM) plants. Two ecotypes of Elymus glaucus (blue wild rye) were exposed to mycorrhizal inoculation and episodic ozone exposures simulating atmospheric conditions in the Los Angeles Basin. Preliminary results show that effects of ozone on growth were subtle. In both ecotypes, growth of aboveground biomass was not affected by ozone while root growth was decreased. In most treatments, mycorrhizal inoculation decreased growth of leaves and stems, but had no significant effect on root growth. Three-way ANOVA tests indicated interactive effects between ecotype, mycorrhiza and ozone. Further experimental work is needed to reveal the biological processes governing these responses.

  6. The vesicular-arbuscular mycorrhizal symbiosis | Quilambo | African ...

    African Journals Online (AJOL)

    African Journal of Biotechnology. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 2, No 12 (2003) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

  7. Effect of vesicular arbuscular mycorrhizal fungus on the ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-10-06

    Oct 6, 2008 ... were estimated following the method of Dubois et al. (1956). The amount of nitrate formed was measured by the method of Cataldo et al. (1975). Estimation of praline was done according to Bates. (1973). The dried plant materials were ground in porcelain mortar with porcelain pestle and the N content was ...

  8. Mycorrhiza helper bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Deveau, Aurelie [French National Insitute for Agricultural Research (INRA); Labbe, Jessy [ORNL

    2016-10-01

    This chapter focuses on the Mycorrhiza Helper Bacteria (MHB), a generic name given to bacteria which stimulate the formation of mycorrhizal symbiosis. By extension, some bacterial strains that positively impact the functioning of mycorrhizal symbiosis are also called MHB. These bacteria have applicative interests, as they indirectly improve the health and growth of tree seedlings. MHB are not restricted to a specific type of ecosystem, but are rather generalist in the way that they associate with both herbaceous and woody mycorrhizal plants from boreal, temperate, arid and tropical ecosystems. However, understanding the molecular mechanisms and their specificities will help us to know more about the ecology of the MHB. The process of acquisition varies between fungal species; while ectomycorrhizal fungi most probably recurrently acquire them from the environment, the association between bacterial endosymbionts and Glomeromycota probably dates back to very ancient times, and has since been vertically transmitted.

  9. A Combined Experimental and Computational Study of Vam3, a Derivative of Resveratrol, and Syk Interaction

    Directory of Open Access Journals (Sweden)

    Ming Jiang

    2014-09-01

    Full Text Available Spleen tyrosine kinase (Syk plays an indispensable role through preliminary extracellular antigen-induced crosslinking of Fc receptor (FcR in the pathogenesis of autoimmune disorders, such as rheumatoid arthritis. In this study, we identify Vam3, a dimeric derivative of resveratrol isolated from grapes, as an ATP-competitive inhibitor of Syk with an IC50 of 62.95 nM in an in vitro kinase assay. Moreover, docking and molecular dynamics simulation approaches were performed to get more detailed information about the binding mode of Vam3 and Syk. The results show that 11b-OH on ring-C and 4b-OH on ring-D could form two hydrogen bonds with Glu449 and Phe382 of Syk, respectively. In addition, arene-cation interaction between ring-D of Vam3 and Lys402 of Syk was also observed. These results indicate that ring-C and D play an essential role in Vam3–Syk interaction. Our studies may be helpful in the structural optimization of Vam3, and also aid the design of novel Syk inhibitors in the future.

  10. Mycorrhizae in forest tree nurseries

    Science.gov (United States)

    Michelle M. Cram; R. Kasten Dumroese

    2012-01-01

    Mycorrhizae are symbiotic fungus-root associations. The colonization of roots by mycorrhizal fungi can benefit the host by improving nutrient and water uptake. In exchange, the host plant provides the mycorrhizal fungi carbohydrates (carbon) from photosynthesis. A substantial portion of this carbon is ultimately transferred to the rhizosphere and is estimated to...

  11. Value Adding Management (VAM) of buildings and facility services in four steps

    NARCIS (Netherlands)

    van der Voordt, Theo; Jensen, Per Anker; Hoendervanger, Jan Gerard; Bergsma, Feike

    2016-01-01

    This paper presents a new Value Adding Management (VAM) model that aims to support decision makers in identifying appropriate interventions in buildings, other facilities and services that add value to the organisation, to manage its implementation, and to measure the output and outcomes. The paper

  12. Application of the EDYS Model to Evaluate Control Methods for Invasive Plants at Yakima Training Center, Washington

    Science.gov (United States)

    2004-12-01

    Anderson. 1987. Effects of soil moisture and soil sterilization on vesicular- arbuscular mycorrhizal colonization and growth of little bluestem...potassium, and in the density of mycorrhiza , in biennial and matrix-forming perennial species of closed chalkland turf. Journal of Ecology 70:571-593...nitrogen between pasture plants infected with vesicular- arbuscular mycorrhizal fungi. New Phytologist 108:417-423. Heil, G.W. and W.H. Diemont. 1983

  13. Utilization of arbuscular mycorrhiza by system management

    OpenAIRE

    Kahiluoto, Helena; Vestberg, Mauritz

    2000-01-01

    Mycorrhiza is an ecosystem service which can be relied on and favoured, but also impaired or irreversibly lost depending on the production system. Arbuscular mycorrhiza (AM) deserves to be considered in development of sustainable farming systems as well as in breeding and soil quality assessment programmes serving sustainable agriculture. AM effectiveness in field soils can be assessed using a standardized bioassay.

  14. The mycorrhiza helper bacteria revisited.

    Science.gov (United States)

    Frey-Klett, P; Garbaye, J; Tarkka, M

    2007-01-01

    In natural conditions, mycorrhizal fungi are surrounded by complex microbial communities, which modulate the mycorrhizal symbiosis. Here, the focus is on the so-called mycorrhiza helper bacteria (MHB). This concept is revisited, and the distinction is made between the helper bacteria, which assist mycorrhiza formation, and those that interact positively with the functioning of the symbiosis. After considering some examples of MHB from the literature, the ecological and evolutionary implications of the relationships of MHB with mycorrhizal fungi are discussed. The question of the specificity of the MHB effect is addressed, and an assessment is made of progress in understanding the mechanisms of the MHB effect, which has been made possible through the development of genomics. Finally, clear evidence is presented suggesting that some MHB promote the functioning of the mycorrhizal symbiosis. This is illustrated for three critical functions of practical significance: nutrient mobilization from soil minerals, fixation of atmospheric nitrogen, and protection of plants against root pathogens. The review concludes with discussion of future research priorities regarding the potentially very fruitful concept of MHB.

  15. Mycorrhiza: A Common Form of Mutualism.

    Science.gov (United States)

    Medve, Richard J.

    1978-01-01

    Mycorrhizae are among the most common examples of mutualism. This article discusses their structure, symbolic relationship, factors affecting formation and applying research. Questions are posed and answers suggested. (MA)

  16. Mycorrhizae in Agroforestry: a Case-study

    OpenAIRE

    NUHAMARA, S.T

    1987-01-01

    Census of mycorrhizae in Shorea javanica agroforests has been made periodically in the district of Krui, Lampung, Sumatra. Amanita hemibapha (Amanitaceae), Cantharellus cibarius (Cantharella-ceae), Lactarius spp., Russula spp. (Russulaceae) and Scleroderma sp. (Sclerodermataceae) were commonly encountered on the agroforest floor. These mycorrhizal fungi are naturally associated with the planted trees. The significance of mycorrhizae for the maximization of growth and sustained productivity o...

  17. Root hydraulic conductivity and xylem sap levels of zeatin riboside and abscisic acid in ectomycorrhizal Douglas fir seedlings

    Science.gov (United States)

    Mark D. Coleman; Caroline S. Bledsoe; Barbara A. Smit

    1990-01-01

    Mechanistic hypotheses to explain mycorrhizal enhancement of root hydraulic conductivity (Lp) suggest that phosphorus (P) nutrition, plant growth substances and/or altered morphology may be responsible. Such ideas are based on work with VA (vesicular-arbuscular) mycorrhizas. Since VA mycorrhizas and ectomycorrhizas differ in many respects, they...

  18. Mycorrhiza

    Indian Academy of Sciences (India)

    The symbiotic association between plant and fungi (mycor- rhizal association) is an amazing phenomenon observed in nature. The mycorrhizal association is one of nature's boons for sustainable agriculture. In today's changing environment, indiscriminate use of pesticides and chemicals pose a great threat to the existence ...

  19. Effects of Moisture and Mycorrhiza on Stomatal Conductance and ...

    African Journals Online (AJOL)

    acer

    Both the ecto and endo mycorrhizae significantly (P<0.05)affected the Stomatal Conductance and Xylem Pressure Potential of the plant even under stressed conditions. The use of mycorrhiza is thus recommended as a strategy for efficient water utilization and water conservation. KEYWORDS: Faidherbia albida, mycorrhiza, ...

  20. Diversity and Plant Growth Promoting Properties of Rhizobacteria ...

    African Journals Online (AJOL)

    characteristics of plant growth promoting rhizobacteria (PGPR) and hence selected for further study. The sixty six isolates were further ... microorganisms as inoculum to boost production of the crop could be one of the potential ... vesicular arbuscular mycorrhizal (VAM) fungi (Glomus fasiculatum) on mineral content of tef.

  1. Effect of manganese on endomycorrhizal sugar maple seedlings

    Science.gov (United States)

    George A. Schier; Carolyn J. McQuattie

    2002-01-01

    Manganese (Mn) toxicity may play an important role in the poor survival of seedlings in declining sugar maple (Acer saccharum Marsh.) stands in northern Pennsylvania. To determine the effect of Mn on the growth of sugar maple seedlings, 1-year-old seedlings inoculated with vesicular-arbuscular mycorrhizal (VAM) fungi and growing in sand-vermiculite-...

  2. Full-scale demonstration of treatment of mechanically separated organic residue in a bioreactor at VAM in Wijster

    NARCIS (Netherlands)

    Oonk, H.; Woelders, H.

    1999-01-01

    At the VAM waste treatment company in Wijster a demonstration is in progress of bioreactor technology for the treatment of mechanically separated organic residue (MSOR) of a waste separation plant. This bioreactor is an in situ fermentation cell in which physical, chemical and biological processes

  3. Hesiod and Hávamál: Transitions and the Transmission of Wisdom

    Directory of Open Access Journals (Sweden)

    Lilah Grace Canevaro

    2014-03-01

    Full Text Available This article offers fresh insights into Hesiod’s Works and Days by comparing it with the Eddic Hávamál, a didactic poem far removed in terms of geography and date, but compellingly close in subject matter, construction, and transmission. It finds parallels between the poems in the methods of teaching and in what is being taught, focusing on the shared theme of self-sufficiency (both intellectual and practical. It finds parallels in structure, as Hávamál is, like the Works and Days, made up not only of precepts and maxims but also of elaborate mythological sections, and is associated with catalogic elements which may be original or later accretions, just like Hesiod’s Days, or the Catalogue of Women, or the Ornithomanteia. This article also traces parallel scholarly trajectories, exploring the strikingly similar histories of scholarship on the two poems. Finally, this paper finds parallels in the transmission of the poems, as both are rooted in the oral tradition but poised at a crucial juncture: the advent of writing. Despite the striking similarities between the poems, this paper refrains from any suggestion of a straight channel of reception but rather interprets the parallels as a reflection of comparable societies, or at least societies at comparable points in their developments. Archaic Greece and Viking Scandinavia might not be exactly parallel cultures, but they evidently share certain cultural concerns: as agrarian societies with strong family and household structures, polytheistic religions and honor codes, they offer similar advice in similar formulations through similar didactic strategies. Such similarities may encourage us to think in terms of the shared characteristics of transitional products. If we exclude direct reception we are left with a cultural constant: the transmission of wisdom. And with recurring elements such as gnomic language, myth and catalogue, we are also left with constant expressions of that wisdom.

  4. Comparative Nitrogen fixation, native arbuscular mycorrhiza ...

    African Journals Online (AJOL)

    bean produced approximately 5 and 6 t/ha biomass whereas Mucuna and Canavalia yielded about 2 t/ha biomass each. Although cowpea had the least number of arbuscular mycorrhiza fungal (AMF) spores in its rhizosphere, its roots were the ...

  5. The application of mycorrhiza in horticulture

    Directory of Open Access Journals (Sweden)

    Marija ZRNIC

    2017-09-01

    Full Text Available This article gives a review of scientific and professional literature regarding the application of mycorrhizas in horticulture. It defines the phenomenon of mycorrhizal symbiosis and describes some of the basic features of symbiotic relationships between plants and fungi. It specifies most common types of mycorrhizas appearing in nature, their characteristics and differences considering diverse hosts, symbiotic fungi and nature of their relationship. The main objective of the article is to demonstrate the effects of mycorrhizal colonization on various agricultural, physiological and biochemical properties of horticultural crops. It also proposes an important influence of mycorrhization on plant nutrition, nutrient uptake and crop yields. Researches show that plants with mycorrhiza are more tolerant to nutrients and water stress, soil salinity and high heavy metals concentrations. Also, it has been shown that mycorrhizal symbiosis positively affects plants during attacks of foliar pathogens and plant-parasitic nematodes. These effects propose the possibility of use of mycorrhizas in sustainable agroecosystems, but the relationship between plants, mycorrhizal fungi and soil type is yet to be elucidated.

  6. Inzet van mycorrhiza's in de bollenteelt

    NARCIS (Netherlands)

    Boer, de M.; Breeuwsma, S.J.; Baar, J.; Hiddink, G.A.

    2005-01-01

    In samenwerking met PPO-paddestoelen is door PPO-bloembollen in Lisse een proef met hyacinten opgezet waarin het effect van mycorrhiza-preparaten op gewasgroei en bestrijding van Pythium-wortelrot werd getest. Uit de eerste resultaten in het voorjaar bleek dat er nauwelijks kolonisatie van de

  7. Arbuscular mycorrhiza in soil quality assessment

    DEFF Research Database (Denmark)

    Kling, M.; Jakobsen, I.

    1998-01-01

    Arbuscular mycorrhizal (AM) fungi constitute a living bridge for the transport of nutrients from soil to plant roots, and are considered as the group of soil microorganisms that is of most direct importance to nutrient uptake by herbaceous plants. AM fungi also contribute to the formation of soil...... aggregates and to the protection of plants against drought and root pathogens. Assessment of soil quality, defined as the capacity of a soil to function within ecosystem boundaries to sustain biological productivity, maintain environmental quality, and promote plant health, should therefore include both...... quantitative and qualitative measurements of this important biological resource. Various methods for the assessment of the potential for mycorrhiza formation and function are presented. Examples are given of the application of these methods to assess the impact of pesticides on the mycorrhiza....

  8. Mycorrhiza in sedges--an overview.

    Science.gov (United States)

    Muthukumar, T; Udaiyan, K; Shanmughavel, P

    2004-04-01

    Most terrestrial plants associate with root-colonising mycorrhizal fungi, which improve the fitness of both the fungal and plant associates. However, exceptions exist both between and within plant families failing to associate with mycorrhizal fungi or in the incidence and the extent of mycotrophy, which may vary greatly. Sedges are important pioneers of disturbed habitats and often dominate vegetations like wetlands, and arctic and alpine vegetations, in which the mycorrhizal inoculum in the soil is often low or absent. In the past, sedges were often designated as non-mycorrhizal, though limited reports indicated the presence of mycorrhiza in certain species. However, studies since 1987 indicate widespread occurrence of mycorrhiza in sedges. Based on these studies, the family Cyperaceae is no longer a non-mycorrhizal family, but the mycorrhizal status of its members is greatly influenced by environmental conditions. Further, sedges appear to have several morphological adaptations to thrive in the absence of mycorrhizal association. Though mycorrhizal associations have been noted in many sedge species, the ecological role of this association is not well documented and no clear generalisation can be drawn. Similarly, the role of mycorrhizal fungi on sedge growth and nutrient uptake or non-nutritional benefits has yet to be fully ascertained. This paper reviews the current information available on the incidence of mycorrhiza in sedges and the possible reasons for low mycotrophy observed in this family.

  9. EVALUASI PEMBAGIAN RASKIN DI KABUPATEN BANTUL TAHUN 2007 DENGAN PENDEKATAN VULNERABILITY ANALYSIS AND MAPPING (VAM

    Directory of Open Access Journals (Sweden)

    K Karsinah

    2015-12-01

    Full Text Available The goal of raskin program is to give the protection to the poor and vulnerability families by given the subsidized rice although they meet the nutrition need and reduce the poor families expenditure. Targeting the poor families eligible often not efficient. Bad targeting give the impact to the raskin program, some of program benefit leaked to non needy families. The research attempted to determine the area or region in Bantul the could be categorized into food vulnerability using VAM methods so they would be the targer of raskin program. The data used in the research were secondary data consist of classification and leveling family data in all area in Bantul in the year 2006 and raskin allocation data in Bantul in the year 2007. The finding of this research indicated that 17 areas observed, only 3 areas could be categorized in highest vulnerability, 7 areas categorized in high vulnerability, 2 areas categorized in medium vulnerability, 1 areas categorized in low vulnerability, 4 areas categorized in lowest vulnerability.

  10. Occurrence of mycorrhizae after logging and slash burning in the Douglas-fir forest type.

    Science.gov (United States)

    Ernest Wright; Robert F. Tarrant

    1958-01-01

    The association of certain fungi with plant roots results in formation of an organ called a mycorrhiza. There are two principal types of mycorrhizae: those with the fungus confined internally in the root, or endotrophic mycorrhizae, and those with both internal fungus development and an external fungal mantle enveloping the root tips, or ectotrophic mycorrhizae....

  11. The Central Polybasic Region of the Soluble SNARE (Soluble N-Ethylmaleimide-sensitive Factor Attachment Protein Receptor) Vam7 Affects Binding to Phosphatidylinositol 3-Phosphate by the PX (Phox Homology) Domain.

    Science.gov (United States)

    Miner, Gregory E; Starr, Matthew L; Hurst, Logan R; Sparks, Robert P; Padolina, Mark; Fratti, Rutilio A

    2016-08-19

    The yeast vacuole requires four SNAREs to trigger membrane fusion including the soluble Qc-SNARE Vam7. The N-terminal PX domain of Vam7 binds to the lipid phosphatidylinositol 3-phosphate (PI3P) and the tethering complex HOPS (homotypic fusion and vacuole protein sorting complex), whereas the C-terminal SNARE motif forms SNARE complexes. Vam7 also contains an uncharacterized middle domain that is predicted to be a coiled-coil domain with multiple helices. One helix contains a polybasic region (PBR) composed of Arg-164, Arg-168, Lys-172, Lys-175, Arg-179, and Lys-186. Polybasic regions are often associated with nonspecific binding to acidic phospholipids including phosphoinositides. Although the PX (phox homology) domain alone binds PI3P, we theorized that the Vam7 PBR could bind to additional acidic phospholipids enriched at fusion sites. Mutating each of the basic residues in the PBR to an alanine (Vam7-6A) led to attenuated vacuole fusion. The defective fusion of Vam7-6A was due in part to inefficient association with its cognate SNAREs and HOPS, yet the overall vacuole association of Vam7-6A was similar to wild type. Experiments testing the binding of Vam7 to specific signaling lipids showed that mutating the PBR to alanines augmented binding to PI3P. The increased binding to PI3P by Vam7-6A likely contributed to the observed wild type levels of vacuole association, whereas protein-protein interactions were diminished. PI3P binding was inhibited when the PX domain mutant Y42A was introduced into Vam7-6A to make Vam7-7A. Thus the Vam7 PBR affects PI3P binding by the PX domain and in turn affects binding to SNAREs and HOPS to support efficient fusion. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  12. Arbuscular mycorrhiza contribution to the growth performance and ...

    African Journals Online (AJOL)

    Arbuscular mycorrhiza contribution to the growth performance and heavy metal uptake of Helianthus annuus LINN in pot culture. ... Results showed that arbuscular mycorrhiza (AM) fungi significantly (p ≤ 0.05) influenced the number of leaves, plant height and stem girth of sunflower plants only at 80 mg Cd kg-1 ...

  13. Effect of mycorrhiza and pruning regimes on seasonality of ...

    African Journals Online (AJOL)

    GRACE

    2006-07-16

    Jul 16, 2006 ... Effect of mycorrhiza and pruning regimes on seasonality of hedgerow tree mulch contribution to .... Mycorrhizae are symbiotic association between plant roots and certain soil fungi (Sieverding, 1991). ..... inoculum was put under the seeds in the polythene bags for inoculated hedgerow tree seedlings and ...

  14. Mycorrhizas on nursery and field seedlings of Quercus garryana

    Science.gov (United States)

    Dariene Southworth; Elizabeth M. Carrington; Jonathan L. Frank; Peter Gould; Connie A. Harrington; Warren D. Devine

    2009-01-01

    Oak woodland regeneration and restoration requires that seedlings develop mycorrhizas, yet the need for this mutualistic association is often overlooked. In this study, we asked whether Quercus garryana seedlings in nursery beds acquire mycorrhizas without artificial inoculation or access to a mycorrhizal network of other ectomycorrhizal hosts. We...

  15. Arbuscular, ecto-related, orchid mycorrhizas--three independent structural lineages towards mycoheterotrophy: implications for classification?

    Science.gov (United States)

    Imhof, Stephan

    2009-08-01

    The classification of mycorrhizas in seven equally ranked types glosses over differences and similarities and, in particular, does not acknowledge the structural diversity of arbuscular mycorrhizas. This article emphasizes the parallel continua of ecto-related mycorrhizas and arbuscular mycorrhizas, exemplified within Ericaceae and Gentianales, respectively, as well as the proprietary development of orchid mycorrhizas, all three of which have independently developed mycoheterotrophic plants. A hierarchical classification according to structural similarities is suggested.

  16. Efecto de algunos fungicidas sobre la interacción Rhizoctonia solani Kuhn-Micorriza vesículo arbuscular en soya, Glycine max Merril

    Directory of Open Access Journals (Sweden)

    Sánchez de Prager Marina

    1987-09-01

    Full Text Available En el campo se dispuso de dos preparaciones de suelo: natural y desinfectado químicamente (Ditrapex-CE y en el invernadero de suelo esterilizado con vapor. Se utilizaron los fungicidas Propamocarb, SN-84364, PCNB y Vitavax-300. Se contó con la flora micorrizógena natural y una cepa introducida, Glomus manihotis. R. solani disminuyó en un 50 % la emergencia de la soya, comportándose más agresivo en suelo desinfectado. En los primeros 15 días su ataque se incrementó y redujo el desarrollo de MVA en suelo natural. Al avanzar la edad de la planta decreció su infección. Con relación a la MVA la tendencia es contraria. La presencia de la MVA, incluyendo G. manihotis no incrementó significativamente la materia seca y el rendimiento de la soya. Al desinfectar el suelo los fungicidas afectaron negativamente la infección micorrizógena, mientras que en suelo natural no sucedió este fenómeno, al contrario SN-84364 incrementó su presencia. Este producto es el que menos afecta la simbiosis en el suelo desinfectado. Los fungicidas SN-84364 y PCNB mostraron gran especificidad contra R. solani y Vitavax-300 mayor espectro de acción.With the object to evaluate in the soybeans crop behavior in the interaction of Rhizoctonia solani, vesicular-arbuscular mycorrhizae (VAM and fungicides used to treatment of seed, two different soil preparations were used in the field trials: natural and chemically disinfected (Ditrapex-CE and under greenhouse: using vapor- sterilized. Was utilized the fungicides Propamocarb, SN-84364, PCNB y Vitavax- 300. Be had into account the natural mycorrhizal flora and a source of Glomus manihotis introduced. R. solani reduced the emergence of soybean by 50%, the above-metioned pathogen was more agressive in disinfected soil. In the 15 days first the attack increased and reduced the VAM development in the natural soil. With the age of the plant the pathogen infection decreased. With relation by VAM is contrary the tendency

  17. Cloning arbuscule-related genes from mycorrhizas

    DEFF Research Database (Denmark)

    Burleigh, Stephen

    2000-01-01

    Until recently little was known about the identity of the genes expressed in the arbuscules of mycorrhizas, due in part to problems associated with cloning genes from the tissues of an obligate symbiont. However, the combination of advanced molecular techniques, innovative use of the materials...... available and fortuitous cloning has resulted in the recent identification of a number of arbuscule-related genes. This article provides a brief summary of the genes involved in arbuscule development, function and regulation, and the techniques used to study them. Molecular techniques include differential...

  18. Shifts in soil fungal communities in Tuber melanosporum plantations over a 20-year transition from agriculture fields to oak woodlands

    Directory of Open Access Journals (Sweden)

    Liu Bing

    2016-04-01

    Full Text Available Aim of study: To explore the diversity of soil fungi found in black truffle (Tuber melanosporum plantations following the introduction of the mycorrhizal-colonized host tree, (Quercus ilex, through the development of the brûlé and production of mature sporocarps.Area of study: This research was carried out province of Teruel, Aragon (central eastern Spain.Material and Methods: Soil samples from 6 plantations were collected beneath Q. ilex trees inoculated with T. melanosporum, of 3, 5, 7, 10, 14 and 20 years after out planting in truffle plantations. Soil DNA was extracted, PCR-amplified and sequenced to compare soil fungi present at different ages.Main results: As tree age increased, we observed an increased frequency of T. melanosporum (from 8% to 71% of sequenced colonies and concomitant decrease in the combined frequency of Fusarium spp. and Phoma spp. (from 64% to 3%.Research highlights: There are important shifts in species richness and in functional groups in the soil fungal communities in maturing black truffle-oak woodland plantations. The observed inverse relationship between the frequency of soil endophytic and/or pathogenic fungi and that of the mycorrhizal mutualist T. melanosporum provides support to continue a deeper analysis of shifts in fungal communities and functional groups where there is a transition from agriculture fields to woodlands.Abbreviations used: Ectomycorrhiza (ECM fungus; Vesicular arbuscular mycorrhiza (VAM; Operational taxonomic unit (OTU.

  19. Mycorrhizas and dark septate root endophytes in polar regions

    OpenAIRE

    Newsham, K.K.; Upson, R.; Read, D J

    2009-01-01

    We review the distributions and functions of mycorrhizas and dark septate root endophytes in polar regions. Arbuscular mycorrhizas (AM) are present in the Arctic and Antarctic to 82 ºN and 63 ºS, respectively, with fine endophyte being the dominant form of AM in roots at higher latitudes. Ecto- (ECM) and ericoid (ERM) mycorrhizas both occur in the Arctic to 79 ºN, owing to the presence of species of Salix, Dryas, Vaccinium and Cassiope to this latitude. ECM and ERM are not present in Antarcti...

  20. A history of research on arbuscular mycorrhiza.

    Science.gov (United States)

    Koide, Roger T; Mosse, Barbara

    2004-07-01

    This is not a review paper in the traditional sense, of which there are many. Three of the most influential reviews that summarized well some of the "older" literature include those by Nicolson (1967), Gerdemann (1968) and Mosse (1973). Instead, in this brief and incomplete work, we attempt to show the historical development of research on arbuscular mycorrhizas. We owe much to those who have written other historical accounts, including Rayner (1926-1927), Trappe and Berch (1985), Mosse (1985), Schenck (1985), Harley (1991) and Allen (1996), but the contents of this work naturally reflect our own ignorance, interests and biases. It was often difficult to distinguish between the historical and the contemporary, and we did not use any specific cutoff date in making this distinction. The degree to which we include "contemporary" literature was determined by our own assessment of its connectedness to older literature. In any case, we hope this will be of some interest to those of you who study the arbuscular mycorrhiza, and that it will serve the purpose of providing what we consider to be an important historical context for current researchers. We wish you good fortune in your research.

  1. Analysis of Arbuscular Mycorrhizas Using Symbiosis-Defective Plant Mutants

    National Research Council Canada - National Science Library

    John F. Marsh; Michael Schultze

    2001-01-01

    Arbuscular mycorrhizas (AM), mutualistic plant-fungus symbioses formed on the majority of land plants, appear to play an important role in plant mineral nutrition, plant health, and might influence the structure of plant communities...

  2. Mycorrhizae Applications in Horticultural Production on Plant growth

    OpenAIRE

    Ortas, Ibrahim

    2009-01-01

    Mycorrhizae Applications in Horticultural Production on Plant growth and Nutrient Uptake Under Field Conditions Ibrahim ORTAS Department of Soil Science, University of Çukurova, Faculty of Agriculture, Adana, Turkey Mycorrhiza application in horticultural production in East Mediterranean region was tested under field conditions for several years. At field conditions, effect of several mycorrhizal species inoculation on seedling survive and plant growth along has be...

  3. The Effects of Arbuscular Mycorrhiza Fungi on Dry Matter and Concentrations of Nitrogen, Phosphorus and Potassium in Berseem Clover, by Cadmium stress

    Directory of Open Access Journals (Sweden)

    hashem aram

    2016-02-01

    Full Text Available Introduction: Soil contaminations with heavy metals represent a potential risk to the biosphere and leads to increased concentration in ground and surface water. Therefore metals mobility in soil has been extensively studied in the last decades. Use of agrochemicals such as synthetic fertilizers and pesticides has resulted in soil and water pollution, and loss of biodiversity. Cadmium is a heavy metal with a strong effect on crop quality. Moreover, it is a very mobile element in the environment. Plants can easily uptake cadmium and transfer it to other organs. Experiments on the effects of cadmium on the contents of macro elements in plants are scarce and therefore the mechanism of its effect has not yet been fully explained. Contaminated soil can be remediated by chemical, physical or biological techniques. Mycorrhiza is the mutualistic symbiosis (non-pathogenic association between soil-borne fungi with the roots of higher plants. Arbuscular mycorrhizal fungi (AMF are obligate biotrophs, which can form mutualistic symbioses with the roots of around 80% of plant species. Arbuscular mycorrhiza have been observed to play a vital role in metal tolerance and accumulation. Many workers have reported enhancement of phosphate uptake and growth of leguminous plants by vesicular arbuscular mycorhizal fungi (AMF. Materials and Methods: One study performed the factorial experiment based on completely randomized design (CRD with three replications in the greenhouse of Agriculture Faculty of Zanjan University. The examined factors include different levels of arbuscular mycorrhizal fungi inoculation (Glomus mosseae (with and without inoculation, and different levels of soil contamination by cadmium (0, 5, 10, 20, 40 and 80 ppm. In this study, arbuscular mycorrhizal fungi Glomus mosseae species were used. These fungi were prepared by the Plant Protection Clinic in Iran – Hamedan. The soil was prepared of arable land of depth of 0-20 cm at the University of

  4. The Atg17-Atg31-Atg29 Complex Coordinates with Atg11 to Recruit the Vam7 SNARE and Mediate Autophagosome-Vacuole Fusion.

    Science.gov (United States)

    Liu, Xu; Mao, Kai; Yu, Angela Y H; Omairi-Nasser, Amin; Austin, Jotham; Glick, Benjamin S; Yip, Calvin K; Klionsky, Daniel J

    2016-01-25

    Macroautophagy (hereafter autophagy) is an evolutionarily conserved process in which portions of the cytoplasm are engulfed, degraded, and subsequently recycled. The Atg17-Atg31-Atg29 complex translocates to the phagophore assembly site (PAS), where an autophagosome forms, at a very early stage of autophagy, playing a vital role in autophagy induction. Here, we identified a novel role of this complex in a late stage of autophagy where it coordinates with Atg11 to regulate autophagy-specific fusion with the vacuole. Atg17 and Atg11 interact with the vacuolar SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein receptor) Vam7 independently of each other. Several hydrophobic residues in helix 1 and helix 4 of Atg17 and the SNARE domain of Vam7 mediate the Atg17-Vam7 interaction. An F317D mutation of Atg17, which diminishes its interaction with Vam7 without affecting its interaction with Atg13 or Atg31, leads to a defect in the fusion of autophagosomes with the vacuole and decreased autophagy activity. These results provide the first demonstration that the Atg17-Atg31-Atg29 complex functions in both early and late stages of autophagy and also provide a mechanistic explanation for the coordination of autophagosome completion and fusion with the vacuole. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Comparación de las velocidades alcanzadas entre dos test de campo de similares características: VAM-EVAL y UMTT

    Directory of Open Access Journals (Sweden)

    G.C. García

    2014-06-01

    Conclusión: En estudiantes de educación física no se encontraron diferencias estadísticamente significativas en las VFA entre el UMTT y VAM-EVAL. De igual manera, no se encontraron diferencias en las distancias alcanzadas, la duración de los test y en el VO2máx estimado.

  6. Growth response of Grevillea robusta A. Cunn. seedlings to phosphorus fertilization in acid soils from Kenya

    Directory of Open Access Journals (Sweden)

    Karanja N.K.

    1999-01-01

    Full Text Available Three experiments were conducted to assess the response of Grevillea robusta to phosphorus fertilization using acid soils showing low P levels from Eastern (Gituamba-Andosols and Western (Kakamega-Acrisols Kenya. In the first experiment P was applied as Minjingu phosphate rock (MPR- 13/P at 0, 52 and 77 kg P per ha into 5 kg of soil. In the second experiment 2 g vesicular arbuscular mycorrhizae (VAM soil + root inoculum per 5 kg soil was included in addition to the same MPR rates using Kakamega soil only. In the third experiment, MPR and triple superphosphate (TSP were added to 5 kg Kakamega soil at a rate of 25.8 mg P per kg soil, and 32P isotope dilution techniques were used to assess P uptake in the shoot harvested at 3 and 6 MAT (months after transplanting. Application of MPR to the Andosol reduced height and root collar diameter of G. robusta significantly (p < .05 as compared to the control. Significant increases (p < .05 in height and root collar diameter where P was added compared to control were recorded with the Acrisol. Soil interaction with P fertilizer rates was highly significant (p < .001 for both height and root collar diameter growth. The roots were not infected with VAM upon harvesting at 12 months. At 3 MAT the percentage P derived from the MPR and TSP was 3/ and 6/ respectively. P uptake decreased significantly (p < .05 between 3 and 6 months. The results indicated that addition of P fertilizer in the Acrisols was probably required at the early stages of G. robusta growth but further research and particularly root studies are required to ascertain the above observations.

  7. Validación de un test de natación, evaluando la velocidad aeróbica máxima (VAM) para calcular los ritmos de entrenamiento para triatletas y nadadores

    OpenAIRE

    González Haro, Carlos; Galilea Ballarini, Pedro-Alberto; Drobnic Martínez, Franchec; Padullés i Riu, Josep Maria

    2005-01-01

    El objetivo del presente estudio es validar un test de natación evaluando la Velocidad Aeróbica Máxima (VAM) para prescribir ritmos de entrenamiento. Siete atletas y nadadores nadaron 400 m a la máxima intensidad posible, después realizaron una prueba triangular para evaluar la VAM. Una semana más tarde se midió el tiempo y la distancia límite de la VAM, así como el umbral láctico individual mediante un test progresivo compuesto por seis repeticiones de 200 m a diferentes velocidades. Una sem...

  8. Radiocaesium in fruitbodies and mycorrhizae in ectomycorrhizal fungi

    Energy Technology Data Exchange (ETDEWEB)

    Nikolova, Ivanka [N. Pouskharov Inst. of Soil Sciences and Agroecology, Sofia (Bulgaria); Johanson, K.J. [Swedish Univ. of Agricultural Sciences, Radioecology Dept., Uppsala (Sweden); Dahlberg, Anders [Swedish Univ. of Agricultural Sciences, Forest Mycology and Pathology Dept., Uppsala (Sweden)

    1997-12-31

    Fruitbodies of Suillus variegatus and Lactarius rufus and, at a maximum distance of 50 cm, the corresponding mycorrhizae, were collected on a rocky area in a coniferous forest. The tuberculate mycorrhizae collected close to S. variegatus fruitbodies were identified by the RFLP pattern to be S. variegatus mycorrhizae. In contrast the smooth brown mycorrhizae collected close to fruitbodies of L. rufus were found to be of various species - L. rufus, but also Russula sp. The {sup 137}Cs activity concentrations in fruitbodies and the fungal part of the tuburculate mycorrhizae of S. variegatus were about the same. A local enrichment of {sup 137}Cs within fruitbodies was studied by collecting fruitbodies growing in clusters. Between 13 and 64% of the mean ground {sup 137}Cs deposition of the cluster area (400 or 625 cm{sup 2}) was found in the fruitbodies. This indicates that there might be an important fungal redistribution of {sup 137}Cs in the forest floor during the production of fruitbodies. The distribution of {sup 137}Cs within the fruitbodies was heterogenous. For example in Cortinarious armillatus, the {sup 137}Cs level in the cap was 2.7 times higher compared to in the stripe. (Author).

  9. Plant-mediated 'apparent effects' between mycorrhiza and insect herbivores.

    Science.gov (United States)

    Gilbert, Lucy; Johnson, David

    2015-08-01

    Plants mediate indirect 'apparent' effects between above-ground herbivores and below-ground mutualistic mycorrhizal fungi. The herbivore-plant-mycorrhiza continuum is further complicated because signals produced by plants in response to herbivores can be transmitted to other plants via shared fungal networks below ground. Insect herbivores, such as aphids, probably affect the functioning of mycorrhizal fungi by changing the supply of recent photosynthate from plants to mycorrhizas, whereas there is evidence that mycorrhizas affect aphid fitness by changing plant signalling pathways, rather than only through improved nutrition. New knowledge of the transfer of signals through fungal networks between plant species means we now need a better understanding of how this process occurs in relation to the feeding preferences of herbivores to shape plant community composition and herbivore behaviour in nature. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Isolasi dan karakterisasi mikoriza vesikular-arbuskular di lahan kering masam, Lampung Tengah

    Directory of Open Access Journals (Sweden)

    Prihastuti Prihastuti

    2012-02-01

    Full Text Available This research aimed to determine spore of vesicular-arbuscular mycorrhizae collected from acid dry land of Central Lampung. The character of research was descriptive-explorative. Soil samples were collected by stratified random sampling method. The results indicated that amount of spore at rizospher area reached 33-311 spores/g of soil. There were 8 forms of mycorrhizae spores. The species of mycorrhizae found were Gigaspora margarita, Glomus moseae, Glomus versiforme, Acaulospora sp., Endogone pisiformis, Smilacina racemosa, Entrophospora sp. and Scutellospora sp. Further research is needed for the exploitation land improvement of the effectiveness of natural mycorrhizae on acid dry land at Central Lampung.

  11. III. MYCORRHIZAE IN AGROFORESTRY: A CASE-STUDY

    Directory of Open Access Journals (Sweden)

    S.T. NUHAMARA

    1987-01-01

    Full Text Available Census of mycorrhizae in Shorea javanica agroforests has been made periodically in the district of Krui, Lampung, Sumatra. Amanita hemibapha (Amanitaceae, Cantharellus cibarius (Cantharella-ceae, Lactarius spp., Russula spp. (Russulaceae and Scleroderma sp. (Sclerodermataceae were commonly encountered on the agroforest floor. These mycorrhizal fungi are naturally associated with the planted trees. The significance of mycorrhizae for the maximization of growth and sustained productivity of resin is discussed as well as the need to design well defined agroforestry systems to facilitate growth and to improve production management techniques. INTRODU

  12. Vam3, a compound derived from Vitis amurensis Rupr., attenuated colitis-related tumorigenesis by inhibiting NF-κB signaling pathway

    Directory of Open Access Journals (Sweden)

    Lingling Xuan

    2016-09-01

    Full Text Available Background: Chronic inflammation is one of the important mediators of colitis-related colon cancer (CRC. Abundant mast cells (MCs were observed in the tumor microenvironment and mediators released upon MC activation play an important role in the process of chronic inflammation. Previously, we found that activation of intestine mucosal MCs recruited and modulated the inflammatory CD11b+Gr1+ cells to promote the CRC development. In the current study we investigated the effects of Vam3, a resveratrol dimer with potent anti-inflammatory effects, on CRC development. Methods: RBL-2H3 cells, a basophilic leukemia cell line, were pretreated with 2.5 or 5 μΜ Vam3 and then stimulated with dinitrophenol-conjugated bovine serum albumin (DNP-BSA plus lipopolysaccharide (LPS. The MC degranulation was determined by measuring β-hexosaminidase release. Generation of TNF-α and IL-6 in RBL-2H3 cells or in peritoneal macrophages was determined by ELISA and real-time qPCR. NF-κB p65 and phospho-NF-κB p65 expression was determined by Western blotting. NF-κB activity in RAW264.7 cells was determined by luciferase reporter assay. CRC was induced in C57BL/6 mice by intraperitoneal injection of azoxymethane (AOM, followed by oral exposure to dextran sodium sulfate (DSS. Vam3 at 50 mg/kg, or disodium cromoglycate (DSCG, MC stabilizer at 100 mg/kg, or vehicle were administrated to the mice 4 weeks after DSS withdrawal. Levels of TNF-α, IL-6, and mouse MC protease-1 were determined by ELISA. Infiltration of CD11b+Gr1+ cells was determined by flow cytometry analysis. One-way ANOVA was used to compare difference between groups.Results: Pretreatment with Vam3 significantly inhibited RBL-2H3 cell degranulation and inflammatory cytokine production from RBL-2H3 cells and from peritoneal macrophages. After Vam3 treatment, NF-κB activity in RAW264.7 cells, and expressions of phospho-NF-κB p65 in RBL-2H3 cells and in peritoneal macrophages were significantly down

  13. The yeast ATP-binding cassette (ABC) transporter Ycf1p enhances the recruitment of the soluble SNARE Vam7p to vacuoles for efficient membrane fusion.

    Science.gov (United States)

    Sasser, Terry L; Lawrence, Gus; Karunakaran, Surya; Brown, Christopher; Fratti, Rutilio A

    2013-06-21

    The Saccharomyces cerevisiae vacuole contains five ATP-binding cassette class C (ABCC) transporters, including Ycf1p, a family member that was originally characterized as a Cd(2+) transporter. Ycf1p has also been found to physically interact with a wide array of proteins, including factors that regulate vacuole homeostasis. In this study, we examined the role of Ycf1p and other ABCC transporters in the regulation of vacuole homotypic fusion. We found that deletion of YCF1 attenuated in vitro vacuole fusion by up to 40% relative to wild-type vacuoles. Plasmid-expressed wild-type Ycf1p rescued the deletion phenotype; however, Ycf1p containing a mutation of the conserved Lys-669 to Met in the Walker A box of the first nucleotide-binding domain (Ycf1p(K669M)) was unable to complement the fusion defect of ycf1Δ vacuoles. This indicates that the ATPase activity of Ycf1p is required for its function in regulating fusion. In addition, we found that deleting YCF1 caused a striking decrease in vacuolar levels of the soluble SNARE Vam7p, whereas total cellular levels were not altered. The attenuated fusion of ycf1Δ vacuoles was rescued by the addition of recombinant Vam7p to in vitro experiments. Thus, Ycf1p contributes in the recruitment of Vam7p to the vacuole for efficient membrane fusion.

  14. The Yeast ATP-binding Cassette (ABC) Transporter Ycf1p Enhances the Recruitment of the Soluble SNARE Vam7p to Vacuoles for Efficient Membrane Fusion*

    Science.gov (United States)

    Sasser, Terry L.; Lawrence, Gus; Karunakaran, Surya; Brown, Christopher; Fratti, Rutilio A.

    2013-01-01

    The Saccharomyces cerevisiae vacuole contains five ATP-binding cassette class C (ABCC) transporters, including Ycf1p, a family member that was originally characterized as a Cd2+ transporter. Ycf1p has also been found to physically interact with a wide array of proteins, including factors that regulate vacuole homeostasis. In this study, we examined the role of Ycf1p and other ABCC transporters in the regulation of vacuole homotypic fusion. We found that deletion of YCF1 attenuated in vitro vacuole fusion by up to 40% relative to wild-type vacuoles. Plasmid-expressed wild-type Ycf1p rescued the deletion phenotype; however, Ycf1p containing a mutation of the conserved Lys-669 to Met in the Walker A box of the first nucleotide-binding domain (Ycf1pK669M) was unable to complement the fusion defect of ycf1Δ vacuoles. This indicates that the ATPase activity of Ycf1p is required for its function in regulating fusion. In addition, we found that deleting YCF1 caused a striking decrease in vacuolar levels of the soluble SNARE Vam7p, whereas total cellular levels were not altered. The attenuated fusion of ycf1Δ vacuoles was rescued by the addition of recombinant Vam7p to in vitro experiments. Thus, Ycf1p contributes in the recruitment of Vam7p to the vacuole for efficient membrane fusion. PMID:23658021

  15. On mycorrhiza development of spruces and firs in damaged stands

    Energy Technology Data Exchange (ETDEWEB)

    Ritter, T.; Weber, G.; Kottke, I.; Oberwinkler, F.

    1989-02-01

    The authors studied the very fine roots of sick spruces and firs and established the following: 1. a surprising stability of mycorrhiza development, 2. differences in the dynamism of development and 3. modifications in the composition of the accompanying microfungi. The results suggest connections in the chain of causes of forest disease which have received little attention so far.

  16. Effects of arbuscular mycorrhiza and composted market waste on ...

    African Journals Online (AJOL)

    This study determined effects of composted market waste and Arbuscular Mycorrhiza (AM) on Root Colonization (RC) and fibre yield of kenaf. The experimental design was 2 x 12 factorial in a Completely Randomized Design replicated three times. The treatments were with AM (AM+) and without (AM-) and twelve levels of ...

  17. Effect of mycorrhiza and pruning regimes on seasonality of ...

    African Journals Online (AJOL)

    Effect of mycorrhiza and pruning regimes on seasonality of hedgerow tree mulch contribution to alley-cropped cassava in Ibadan, Nigeria. ... promoted dry season pruning production which was masked in Leucaena at 3 months by biomass diversion into flowering and in Gliricidia with both flowering and mite infestation.

  18. Ecto- or arbuscular mycorrhizas ± which are best?

    Science.gov (United States)

    D. J. Lodge

    2000-01-01

    Few topics in ecology are as intriguing or bedeviling as comparative studies of different types of mycorrhizas formed in the same plant species. Attempts to determine the relative bene®ts from each fungal type to the host plant are fraught with difficulties (Jones et al., 1998), and for this reason plants that form tripartite associations with arbuscular and...

  19. Effects of Mycorrhiza on the Growth and Productivity of Faidherbia ...

    African Journals Online (AJOL)

    The effects of mycorrhiza on growth and growth components of Faidherbia albida (Del.) A. Chev. was investigated in the semi arid environment of Sokoto State, Nigeria. A complete randomized block design with five replications and factorial combination of three watering regimes (daily for unstressed plant, twice weekly for ...

  20. Effects of Mycorrhiza on the Growth and Productivity of Faidherbia ...

    African Journals Online (AJOL)

    acer

    benefit of mycorrhiza to forest trees is that they are highly efficient accumulators of nutrient ions and water in their rhizosphere. The nutrients and water become available to the host plant and to the fungus thereby enhancing nutrition, growth, dry matter production as well as ability to withstand drought (Luyindula and Haque, ...

  1. Glomalin as an indicator of mycorrhizae in tropical agroecosystems

    Science.gov (United States)

    Arbuscular mycorrhizae (AM) are symbiotic mutualistic associations established between the roots of most plants and certain soil fungi. This symbiosis has positive effects on the development and nutrition of plants as it provides them with low mobility soil elements such as P, Zn and Cu. It also imp...

  2. Response of meloidogyne hapla to mycorrhiza fungi inoculation on ...

    African Journals Online (AJOL)

    Five arbuscular mycorrhiza fungi (AMF) isolated from pyrethrum were screened in the greenhouse for efficacy in improving pyrethrum growth and in suppressing a root-knot nematode, Meloidogyne hapla. The fungi screened were Glomus spp. (isolates LM61, ML34 and ML35), Scutellospora sp. (isolate KS74) and ...

  3. Leotia cf. lubrica forms arbutoid mycorrhiza with Comarostaphylis arbutoides (Ericaceae).

    Science.gov (United States)

    Kühdorf, Katja; Münzenberger, B; Begerow, D; Gómez-Laurito, J; Hüttl, R F

    2015-02-01

    Arbutoid mycorrhizal plants are commonly found as understory vegetation in forests worldwide where ectomycorrhiza-forming trees occur. Comarostaphylis arbutoides (Ericaceae) is a tropical woody plant and common in tropical Central America. This plant forms arbutoid mycorrhiza, whereas only associations with Leccinum monticola as well as Sebacina sp. are described so far. We collected arbutoid mycorrhizas of C. arbutoides from the Cerro de la Muerte (Cordillera de Talamanca), Costa Rica, where this plant species grows together with Quercus costaricensis. We provide here the first evidence of mycorrhizal status for the Ascomycete Leotia cf. lubrica (Helotiales) that was so far under discussion as saprophyte or mycorrhizal. This fungus formed arbutoid mycorrhiza with C. arbutoides. The morphotype was described morphologically and anatomically. Leotia cf. lubrica was identified using molecular methods, such as sequencing the internal-transcribed spacer (ITS) and the large subunit (LSU) ribosomal DNA regions, as well as phylogenetic analyses. Specific plant primers were used to confirm C. arbutoides as the host plant of the leotioid mycorrhiza.

  4. Nitrate transport processes in Fagus-Laccaria-mycorrhizae

    NARCIS (Netherlands)

    Kreuzwieser, J; Stulen, [No Value; Wiersema, P; Vaalburg, W; Rennenberg, H

    2000-01-01

    The contribution of influx and efflux of NO3- on NO3- net uptake has been studied in excised mycorrhizae of 18-20 week old beech (Fagus sylvatica L.) trees. Net uptake rates of NO3- followed uniphasic Michaelis-Menten kinetics in the concentration range between 10 mu M and 1.0 mM external NO3-, with

  5. Effect of endomycorrhizae on interactions between mycorrhizal and nonmycorrhizal plants. [Glomus monosporum/mosseae; Atriplex canescens; Sitanion hystrix

    Energy Technology Data Exchange (ETDEWEB)

    Franson, R.; Miller, R.M.

    1984-01-01

    An investigation on how infection with vesicular-arbuscular mycorrhizal fungi (VAM) changes interactions between plants was initiated. Specifically addressed were how does the presence or absence of VAM affect: (1) a species that typically shows little or no infection; and (2) a species that typically possesses moderate levels of infection. Results show: roots for inoculated species were higher than uninoculated treatments; the above ground dry weight gain were significantly higher with inoculation. The growth response of both species suggests a fungus-to-plant interaction even though infection, as measured by arbuscules a vesicles, was not always present. 2 figures. (MF)

  6. Using mycorrhiza-defective mutant genotypes of non-legume plant species to study the formation and functioning of arbuscular mycorrhiza: a review.

    Science.gov (United States)

    Watts-Williams, Stephanie J; Cavagnaro, Timothy R

    2015-11-01

    A significant challenge facing the study of arbuscular mycorrhiza is the establishment of suitable non-mycorrhizal treatments that can be compared with mycorrhizal treatments. A number of options are available, including soil disinfection or sterilisation, comparison of constitutively mycorrhizal and non-mycorrhizal plant species, comparison of plants grown in soils with different inoculum potential and the comparison of mycorrhiza-defective mutant genotypes with their mycorrhizal wild-type progenitors. Each option has its inherent advantages and limitations. Here, the potential to use mycorrhiza-defective mutant and wild-type genotype plant pairs as tools to study the functioning of mycorrhiza is reviewed. The emphasis of this review is placed on non-legume plant species, as mycorrhiza-defective plant genotypes in legumes have recently been extensively reviewed. It is concluded that non-legume mycorrhiza-defective mutant and wild-type pairs are useful tools in the study of mycorrhiza. However, the mutant genotypes should be well characterised and, ideally, meet a number of key criteria. The generation of more mycorrhiza-defective mutant genotypes in agronomically important plant species would be of benefit, as would be more research using these genotype pairs, especially under field conditions.

  7. Arbuscular fungi and mycorrhizae of agricultural soils of the Western Pomerania. Part I. Occurrence of arbuscular fungi and mycorrhizae

    OpenAIRE

    Anna Iwaniuk; Janusz Błaszkowski

    2014-01-01

    This paper presents results of three-year investigations on the occurrence of arbuscular mycorrhizal fungi and arbuscular mycorrhizae of the phylum Glomeromycota in agricultural soils of the Western Pomerania, north-western Poland. The occurrence of these fungi was determined basing on soil-root mixtures collected from both the field and trap cultures.

  8. Effects of Arbuscular Mycorrhiza Inoculation on Growth and Yield of Tomato (Lycopersicum Esculentum Mill.) Under Salinity Stress

    OpenAIRE

    Damaiyanti, D R R; Aini, N; Soelistyono, R

    2015-01-01

    Objective of the research was to study the effect mycorrhiza on growth and yield of tomato. The experiment was conducted in screen house 14 m x 10.5 m, in Pasuruan on November 2013 until March 2014, The experiment was conducted as a factorial randomized complete design. The first factor was dose of mycorrhiza (without mycorrhiza, 5 g mycorrhiza, 10 g mycorrhiza, and 20 g mycorrhiza). The second factor was the salinity stress level (without NaCl, 2500 ppm NaCl, 5000 ppm NaCl, and 7500 ppm NaCl...

  9. Molecular and morphological characterization of Tuber magnatum mycorrhizas in a long-term survey.

    Science.gov (United States)

    Mello, A; Fontana, A; Meotto, F; Comandini, O; Bonfante, P

    2001-03-01

    Tuber magnatum Pico is an ectomycorrhizal fungus whose mycorrhizas can be barely distinguished morphologically from those of other related white truffles. Here we describe the use of specific primers based on the T. magnatum ITS sequence for screening mycorrhizas from a large number of growth chambers, greenhouse and nursery samples taken in a long-term survey. This molecular identification technique enabled a new morphological characterization to be set up for T. magnatum mycorrhizas.

  10. Biochemical Defenses Induced by Mycorrhizae Fungi Glomus Mosseae in Controlling Strawberry Fusarium Wilt.

    Science.gov (United States)

    Yanan, Wang; Xusheng, Zhao; Baozhong, Yin; Wenchao, Zhen; Jintang, Guo

    2015-01-01

    The effect of VAM on reducing wilt caused by Fusarium oxysporum Schlecht. f.sp. fragariae Winks et Williams (FO) infection in strawberry and the possible mechanisms involved were investigated. Two key substance involved in disease defenses, lignin and hydroxyproline-rich glycoprotein were induced and formed in the cell wall of strawberry root, and the peak content of lignin and hydroxyproline-rich glycoprotein occurred on the 25(th) day (149.52mg/g) and on the 15(th) day (10.08 mg/g). The activity of protective enzymes SOD, POD and CAT inoculation with VAM significantly increased when compared with the control under both CK (natural growth) and inoculated with FO. The conductivity of VAM plus FO treatment was higher than the CK treatment, but significantly was lower than the FO treatment.

  11. Environment and Host Affects Arbuscular Mycorrhiza Fungi (AMF) Population.

    Science.gov (United States)

    Rahim, Norahizah Abd; Jais, Hasnah Md; Hassan, Hasnuri Mat

    2016-11-01

    The association of arbuscular mycorrhiza fungi (AMF) and roots undoubtedly gives positive advantages to the host plant. However, heavily fertilised soil such as in oil palm plantation, inhibit the growth of mycorrhiza. Thus, the aim of this research is to distinguish and quantify the availability of AMF population and propagules at different sites of an oil palm plantation by Most Probable Number (MPN) assay. In addition, root infection method was employed to observe host compatibility through the propagation of AMF using two different types of hosts, monocotyledon (Echinochloa cruss-galli) and dicotyledon (Vigna radiata). Three different locations at an oil palm plantation were chosen for sampling. Each location was represented by a distinctive soil series, and were further divided into two sites, that is canopy and midway area. Midway site had a greater population of AMF compared to canopy. The result showed that different environments affect the availability of AMF in the soil. Higher number of AMF infection observed in monocotyledon host suggests that the fibrous root system provide a better association with mycorrhiza.

  12. [Ecological significance of arbuscular mycorrhiza biotechnology in modern agricultural system].

    Science.gov (United States)

    Zhang, Yong; Zeng, Ming; Xiong, Bingquan; Yang, Xiaohong

    2003-04-01

    Mycorrhiza plays a key role in nutrient cycling in ecosystem, and protects host plant against environmental stress. Under natural condition, plant's mycorrhizal structure is a normal phenomenon, and arbuscular mycorrhiza (AM) association is the commonest mycorrhizal type. If well mycorrhizal structure can be formed during plant root system developing process, the quantity and quality of plant production will be improved in large. Because of its effects on plant growth and health, it is accepted that AM symbiosis can reduce chemical fertilizer and pesticide inputs. Consequently, this will lead to a reduction in harmful chemical substance impact on environment. The key effects of AM symbiosis can be summarized as follows: (1) improving rooting and plant establishment; (2) improving uptake of low mobile ions; (3) improving nutrient cycling; (4) enhancing plant tolerance to (biotic and abiotic) stress; (5) improving quality of soil structure; and (6) enhancing plant community diversity. In this paper, the ecological characteristic of arbuscular mycorrhiza fungi (AMF), effects of AM on host plant, and ecologic significance of AM biotechnology in agricultural system were reviewed.

  13. Genetic evidence for auxin involvement in arbuscular mycorrhiza initiation.

    Science.gov (United States)

    Hanlon, Meredith T; Coenen, Catharina

    2011-02-01

    • Formation of arbuscular mycorrhiza (AM) is controlled by a host of small, diffusible signaling molecules, including phytohormones. To test the hypothesis that the plant hormone auxin controls mycorrhiza development, we assessed mycorrhiza formation in two mutants of tomato (Solanum lycopersicum): diageotropica (dgt), an auxin-resistant mutant, and polycotyledon (pct), a mutant with hyperactive polar auxin transport. • Mutant and wild-type (WT) roots were inoculated with spores of the AM fungus Glomus intraradices. Presymbiotic root-fungus interactions were observed in root organ culture (ROC) and internal fungal colonization was quantified both in ROC and in intact seedlings. • In ROC, G. intraradices stimulated presymbiotic root branching in pct but not in dgt roots. pct roots stimulated production of hyphal fans indicative of appressorium formation and were colonized more rapidly than WT roots. By contrast, approaching hyphae reversed direction to grow away from cultured dgt roots and failed to colonize them. In intact seedlings, pct and dgt roots were colonized poorly, but development of hyphae, arbuscules, and vesicles was morphologically normal within roots of both mutants. • We conclude that auxin signaling within host roots is required for the early stages of AM formation, including during presymbiotic signal exchange. © 2010 The Authors. New Phytologist © 2010 New Phytologist Trust.

  14. New Technologies to Reclaim Arid Lands User’s Manual

    Science.gov (United States)

    2002-10-01

    survival of vesicular- arbuscular mycorrhiza propagules during topsoil storage. The Journal of Applied Ecology 22:259-266. Morgan, W. C., A. Wallace, and G...per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing...and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information

  15. United States Air Force Summer Faculty Research Program. Program Technical Report. 1990. Volume 3

    Science.gov (United States)

    1991-06-05

    of Jet Fuel: Effects on Vesicular- Arbuscular Mycorrhizae lii Volume IV 145 Mathematical Modeling and Decision-Making Dr. Miguel Medina for Air Force...transfer. Many special features and algorithms of recent advent in the CFD community are also included in the procedure. With an extensive review and...exchange devices. An excellent review of the application of heat pipes in the aerospace field is offered by Chang and llager[l]. Another important advantage

  16. Comparación de las velocidades alcanzadas entre dos test de campo de similares características: VAM-EVAL y UMTT

    OpenAIRE

    G.C. García; Secchi, J.D.; C.R. Arcuri

    2014-01-01

    Objetivo: El principal objetivo de nuestro estudio fue establecer comparaciones en la velocidad final alcanzada (VFA) en dos test incrementales continuos y máximos; Test de Pista de la Universidad de Montreal (UMTT) y el Test VAM-EVAL. Como objetivo secundario fue comparar el consumo máximo de oxígeno predicho, las distancias recorridas y la duración entre los test. Método: Cuarenta y cinco sujetos (26 hombres), estudiantes de educación física participaron voluntariamente. Fueron evaluados...

  17. Role of phosphate solubilizing Burkholderia spp. for successful colonization and growth promotion of Lycopodium cernuum L. (Lycopodiaceae) in lateritic belt of Birbhum district of West Bengal, India.

    Science.gov (United States)

    Ghosh, Ranjan; Barman, Soma; Mukherjee, Rajib; Mandal, Narayan C

    2016-02-01

    Profuse growth of Lycpodium cernuum L. was found in phosphate deficient red lateritic soil of West Bengal, India. Interaction of vesicular-arbuscular mycorrhiza (VAM) with Lycopodium rhizoids were described earlier but association of PGPR with their rhizoids were not studied. Three potent phosphate solubilizing bacterial strains (P4, P9 and P10) associated with L. cernuum rhizoids were isolated and identified by 16S rDNA homologies on Ez-Taxon database as Burkholderia tropica, Burkholderia unamae and Burkholderia cepacia respectively. Day wise kinetics of phosphate solubilization against Ca3(PO4)2 suggested P4 (580.56±13.38 μg ml(-1)) as maximum mineral phosphate solubilizer followed by P9 (517.12±17.15 μg ml(-1)) and P10 (485.18±14.23 μg ml(-1)) at 28 °C. Release of bound phosphates by isolated strains from ferric phosphate (FePO4), aluminum phosphate (AlPO4) and four different complex rock phosphates indicated their very good phosphate solubilizng efficacy. Nitrogen independent solubilizition also supports their nitrogen fixing capabilities. Inhibition of P solubilization by calcium salts and induction by EDTA suggested pH dependent chelation of metal cations by all of the isolates. Rhizoidal colonization potentials of Burkholderia spp. were confirmed by in planta experiment and also using scanning electron microscope (SEM). Increases of total phosphate content in Lycopodium plants upon soil treatment with these isolates were also recorded. In addition siderophore production on CAS agar medium, tryptophan dependent IAA production and antifungal activities against pathogenic fungi by rhizospheric isolates deep-rooted that they have definite role in nutrient mobilization for successful colonization of L. cernuum in nutrient deficient lateritic soil. Copyright © 2015 Elsevier GmbH. All rights reserved.

  18. The Vam6 and Gtr1–Gtr2 pathway activates TORC1 in response to amino acids in fission yeast

    Science.gov (United States)

    Valbuena, Noelia; Guan, Kun-Liang; Moreno, Sergio

    2012-01-01

    The Rag family of GTPases has been implicated in the TORC1 activation in Drosophila and in mammalian cells in response to amino acids. We have investigated the role of the Rag GTPases Gtr1 and Gtr2 in TORC1 regulation in Schizosaccharomyces pombe. Fission yeast Gtr1 and Gtr2 are non-essential proteins that enhance cell growth in the presence of amino acids in the medium. The function of Gtr1 and Gtr2 in nutrient signaling is further supported by the observation that even in rich medium the deletion of either gene results in the promotion of mating, meiosis and sporulation, consistent with the downregulation of TORC1. We show that Gtr1 and Gtr2 colocalize with TORC1 in vacuoles, where TORC1 is presumably activated. Epistasis analyses indicated that Gtr1 and Gtr2 function downstream of Vam6 and upstream of TORC1 in response to amino acid signals. Our data demonstrate the existence of an evolutionarily conserved pathway with the Vam6 and Gtr1–Gtr2 pathway activating TORC1, which in turns stimulates cell growth and inhibits sexual differentiation. PMID:22344254

  19. Hyphal N transport by a vesicular-arbuscular mycorrhizal fungus associated with cucumber grown at three nitrogen levels

    DEFF Research Database (Denmark)

    Johansen, A.; Jakobsen, I.; Jensen, E.S.

    1994-01-01

    Cucumis sativus L. cv. Aminex (F1 hybrid) was grown alone or in symbiosis with Glomus intraradices Schenck and Smith in containers with two hyphal compartments (HC(A) and HC(B)) on either side of a root compartment (RC) separated by fine nylon mesh. Plants received a total of either 100, 200 or 400...

  20. Hyphal transport by a vesicular-arbuscular mycorrhizal fungus of N applied to the soil as ammonium or nitrate

    DEFF Research Database (Denmark)

    Johansen, A.; Jakobsen, I.; Jensen, E.S.

    1993-01-01

    with a hyphal compartment separated from the root compartment by a fine nylon mesh. Mineral N was then applied to the hyphal compartment as (NH4+)-N-15 or (NO3-)-N-15 at 5 cm distance from the root compartment. Soil samples were taken from the hyphal compartment at 1, 3 and 5 cm distance from the root...

  1. I budet vam stshastje

    Index Scriptorium Estoniae

    2004-01-01

    Viru Keskuses demonstreeritakse Kristiine Kasiino 10. aastapäevale pühendatud Raoul Kurvitza taiest "Õnn kuubis" Hiigelsuur audio-, foto ja videoinstallatsioonidega roosa täring demonstreerib kunstniku nägemust õnnest

  2. Activation Effects of Polysaccharides of Flammulina velutipes Mycorrhizae on the T Lymphocyte Immune Function

    Directory of Open Access Journals (Sweden)

    Zheng-Fei Yan

    2014-01-01

    Full Text Available Flammulina velutipes mycorrhizae have increasingly been produced with increasing of F. velutipes production. A mouse model was thus used to examine potential effect of F. velutipes mycorrhizae on the immune function. Fifty female Wistar mice (5-weeks-old weighed 15–20 g were randomly allocated into five groups. Polysaccharide of F. velutipes mycorrhizae were treated with mice and mice spleen lymphocytes. The levels of CD3+, CD4+, and CD8+ T lymphocyte, interleukin-2 (IL-2, and tumor necrosis factor-a (TNF-α were determined. The results showed that the proportions of CD3+, and CD4+ T lymphocyte, the ratio of CD4+/CD8+, and the levels of IL-2 and TNF-a were significantly increased in polysaccharide of F. velutipes mycorrhizae, while the proportion of CD8+ T lymphocyte was decreased in polysaccharide of F. velutipes mycorrhizae-dose dependent manner. Our findings indicated that a long term exposure of polysaccharide of F. velutipes mycorrhizae could activate the T lymphocyte immune function. Polysaccharide of F. velutipes mycorrhizae was expected to develop into the immune health products.

  3. Activation effects of polysaccharides of Flammulina velutipes mycorrhizae on the T lymphocyte immune function.

    Science.gov (United States)

    Yan, Zheng-Fei; Liu, Nai-Xu; Mao, Xin-Xin; Li, Yu; Li, Chang-Tian

    2014-01-01

    Flammulina velutipes mycorrhizae have increasingly been produced with increasing of F. velutipes production. A mouse model was thus used to examine potential effect of F. velutipes mycorrhizae on the immune function. Fifty female Wistar mice (5-weeks-old) weighed 15-20 g were randomly allocated into five groups. Polysaccharide of F. velutipes mycorrhizae were treated with mice and mice spleen lymphocytes. The levels of CD3(+), CD4(+), and CD8(+) T lymphocyte, interleukin-2 (IL-2), and tumor necrosis factor-a (TNF-α) were determined. The results showed that the proportions of CD3(+), and CD4(+) T lymphocyte, the ratio of CD4(+)/CD8(+), and the levels of IL-2 and TNF-a were significantly increased in polysaccharide of F. velutipes mycorrhizae, while the proportion of CD8(+) T lymphocyte was decreased in polysaccharide of F. velutipes mycorrhizae-dose dependent manner. Our findings indicated that a long term exposure of polysaccharide of F. velutipes mycorrhizae could activate the T lymphocyte immune function. Polysaccharide of F. velutipes mycorrhizae was expected to develop into the immune health products.

  4. Activation Effects of Polysaccharides of Flammulina velutipes Mycorrhizae on the T Lymphocyte Immune Function

    OpenAIRE

    Yan, Zheng-Fei; Liu, Nai-Xu; Mao, Xin-Xin; Li, Yu; Li, Chang-Tian

    2014-01-01

    Flammulina velutipes mycorrhizae have increasingly been produced with increasing of F. velutipes production. A mouse model was thus used to examine potential effect of F. velutipes mycorrhizae on the immune function. Fifty female Wistar mice (5-weeks-old) weighed 15–20 g were randomly allocated into five groups. Polysaccharide of F. velutipes mycorrhizae were treated with mice and mice spleen lymphocytes. The levels of CD3+, CD4+, and CD8+ T lymphocyte, interleukin-2 (IL-2), and tumor necros...

  5. [Influence of elevated atmospheric CO2 on rhizosphere microbes and arbuscular mycorrhizae].

    Science.gov (United States)

    Chen, Jing; Chen, Xin; Tang, Jianjun

    2004-12-01

    The changes of microbial communities in rhizosphere and the formation of mycorrhizae play an important role in affecting the dynamics of plant communities and terrestrial ecosystems. This paper summarized and discussed the effects of elevated atmospheric CO2 on them. Under elevated atmospheric CO2, the carbohydrates accumulated in root systems increased, and the rhizospheric environment and its microbial communities as well as the formation of mycorrhizae changed. It is suggested that the researches in the future should be focused on the effects of rhizosphere microbes and arbuscular mycorrhizae on regulating the carbon dynamics of plant communities and terrestrial ecosystems under elevated atmospheric CO2.

  6. The role of bacteria and mycorrhiza in plant sulfur supply

    Directory of Open Access Journals (Sweden)

    Jacinta Mariea Gahan

    2014-12-01

    Full Text Available Plant growth is highly dependent on bacteria, saprophytic and mycorrhizal fungi which facilitate the cycling and mobilization of nutrients. Over 95% of the sulfur (S in soil is present in an organic form. Sulfate-esters and sulfonates, the major forms of organo-S in soils, arise through deposition of biological material and are transformed through subsequent humification. Fungi and bacteria release S from sulfate-esters using sulfatases, however, release of S from sulfonates is catalyzed by a bacterial multi-component mono-oxygenase system. The asfA gene is used as a key marker in this desulfonation process to study sulfonatase activity in soil bacteria identified as Variovorax, Polaromonas, Acidovorax and Rhodococcus. The rhizosphere is regarded as a hot spot for microbial activity and recent studies indicate that this is also the case for the mycorrhizosphere where bacteria may attach to the fungal hyphae capable of mobilizing organo-S. While current evidence is not showing sulfatase and sulfonatase activity in arbuscular mycorrhiza, their effect on the expression of plant host sulfate transporters is documented. A revision of the role of bacteria, fungi and the interactions between soil bacteria and mycorrhiza in plant S supply was conducted.

  7. [Arbuscular mycorrhiza of cultivated and wild Pinellia ternata].

    Science.gov (United States)

    Cheng, Litao; Guo, Qiaosheng; Liu, Zuoyi

    2010-02-01

    To study the arbuscular mycorrhiza and arbuscular mycorrhizal fungi associated with cultivated and wild Pinellia ternata in Guizhou province. Wild and cultivated P. ternata roots were observed through staining and microscopic examination, the arbuscular mycorrhizal fungi spores were isolated through wet thieving according to Gerdemann & Nicolson (1963), the spores were identified following the description of Schenck & Pérez (1988), and some previous publications. The typical arbuscular mycorrhiza (AM) structure was showed according to a research of wild and cultivated P. ternata. In the survey of AM fungi species in the rhizosphere of wild and cultivated P. ternata, 3 genera and 21 species were found, 3 genera and 7 species were identified. 5 species of them belong to Glomus, 1 species belongs to Scutellospora, 1 species belongs to Gigaspora, including Glomus mosseae, G. intraradices, G. melanosporum, G. deserticola, G. aggregatum, Scutellospora castanea, Gigaspora albida, and one of them was a new record, i.e., Scutellospora castanea which was the dominant species in Bijie. The diversity of AM fungi between wild and cultivated Pinellia ternata was showed on this survey, the fungi associated with wild ones are different form the cultivated ones, such as Gigaspora albida only occurs in cultivated ones, Glomus melanosporum only occurs in wild ones, while Glomus mosseae and Glomus intraradices occur in both wild and cultivated ones, and there were specialization species in Bijie, all these can provide new though for solving degradation problem of cultivated Pinellia ternata.

  8. Giving and Receiving: Measuring the Carbon Cost of Mycorrhizas in the Green Orchid, Goodyera Repens

    National Research Council Canada - National Science Library

    Duncan D. Cameron; Irene Johnson; David J. Read; Jonathan R. Leake

    2008-01-01

    Direct measurement of the carbon (C) 'cost' of mycorrhizas is problematic. Although estimates have been made for arbuscular and ectomycorrhizal symbioses, these are based on incomplete budgets or indirect measurements...

  9. Multiple exocytotic markers accumulate at the sites of perifungal membrane biogenesis in arbuscular mycorrhizas

    NARCIS (Netherlands)

    Genre, A.; Ivanov, S.; Fendrych, M.; Faccio, A.; Zársky, V.; Bisseling, T.; Bonfante, P.

    2012-01-01

    Arbuscular mycorrhizas (AMs) are symbiotic interactions established within the roots of most plants by soil fungi belonging to the Glomeromycota. The extensive accommodation of the fungus in the root tissues largely takes place intracellularly, within a specialized interface compartment surrounded

  10. Arbuscular mycorrhiza reduces phytoextraction of uranium, thorium and other elements from phosphate rock

    Energy Technology Data Exchange (ETDEWEB)

    Roos, Per [Radiation Research Department, Riso National Laboratory, Technical University of Denmark, DK-4000 Roskilde (Denmark); Jakobsen, Iver [Biosystems Department, Riso National Laboratory, Technical University of Denmark, DK-4000 Roskilde (Denmark)], E-mail: iver.jakobsen@risoe.dk

    2008-05-15

    Uptake of metals from uranium-rich phosphate rock was studied in Medicago truncatula plants grown in symbiosis with the arbuscular mycorrhizal fungus Glomus intraradices or in the absence of mycorrhizas. Shoot concentrations of uranium and thorium were lower in mycorrhizal than in non-mycorrhizal plants and root-to-shoot ratio of most metals was increased by mycorrhizas. This protective role of mycorrhizas was observed even at very high supplies of phosphate rock. In contrast, phosphorus uptake was similar at all levels of phosphate rock, suggesting that the P was unavailable to the plant-fungus uptake systems. The results support the role of arbuscular mycorrhiza as being an important component in phytostabilization of uranium. This is the first study to report on mycorrhizal effect and the uptake and root-to-shoot transfer of thorium from phosphate rock.

  11. Arbuscular mycorrhizas in the anthracite and bituminous coal wastes of Pennsylvania

    Energy Technology Data Exchange (ETDEWEB)

    Daft, M.J.; Hacskaylo, E.

    1976-08-01

    The extent of endomycorrhizal infection in herbaceous plants growing on the anthracite and bituminous areas in Pennsylvania was investigated and the possible role of these in plant colonization of coal spoil material assessed. Plants were collected from six sites on three different spoil areas. Most of the herbaceous plants sampled were infected with arbuscular mycorrhizas. Five of the plant species that grew naturally on both types of waste material were both nodulated and mycorrhizal. Gigaspora gigantea and maize infected with mycorrhiza grew on anthracite waste after adjustment of the pH from 4.1 to 6.4, but did not grow on bituminous waste even after the pH was raised. Lucerne that was nodulated and infected with mycorrhiza also grew well on the anthracite waste after the pH was raised. A discussion of the potential importance of arbuscular mycorrhizas in revegetation of coal wastes is included.

  12. The Effect of Mycorrhizae on Plant Growth and Reproduction Varies with Soil Phosphorus and Developmental Stage

    National Research Council Canada - National Science Library

    Margaret L. Ronsheim

    2012-01-01

    .... This study examines the effect of phosphorus level on the response of Allium vineale to mycorrhizae across all plant life stages, including plant fecundity and the relative allocation of resources...

  13. Mycorrhizal diversity in Apostasia (Orchidaceae) indicates the origin and evolution of orchid mycorrhiza

    National Research Council Canada - National Science Library

    Yukawa, Tomohisa; Ogura-Tsujita, Yuki; Shefferson, Richard P; Yokoyama, Jun

    2009-01-01

    ... University, Yamagata 990-8560 Japan ABSTRACT We demonstrated that "orchid mycorrhiza," a specialized mycorrhizal type, appeared in the common ancestor of the largest plant family Orchidaceae and that the...

  14. Metal content in fruit-bodies and mycorrhizas of Pisolithus arrhizus from zinc wastes in Poland

    Directory of Open Access Journals (Sweden)

    Katarzyna Turnau

    2014-08-01

    Full Text Available Pisolithus arrhizus has been selected for investigation as one of the ectomycorrhizal species most resistant to stress factors. Metal content in fruit-bodies and mycorrhizas was estimated to evaluate their role as bioindicators and to check whether mycorrhizas have any special properties for heavy metal accumulation. Fruit-bodies and mycorrhizas were collected from zinc wastes in Katowice-Wełnowiec and analyzed using conventional atomic absorption spectroscopy and energy dispersive spectroscopy accompanying scanning electron microscopy. Differences in tendencies to accumulate metals within sporophores and mycorrhizas were found. The fruit-bodies accumulated Al (up to 640 µg g-1, while high concentrations of Al, Zn, Fe, Ca and Si were noted in the outer mantle of the mycorrhizas. in the material secreted and in the mycelium wali. The content of elements varied depending on the agę of mycorrhizas. The ability of extramatrical mycelium and hyphae forming mycorrhizal mantle to immobilize potentially toxic elements might indicate biofiltering properties though thc next step should include investigations on ability of the fungus to prevent element uptake by the plant.

  15. Successful joint ventures of plants: arbuscular mycorrhiza and beyond.

    Science.gov (United States)

    Ercolin, Flavia; Reinhardt, Didier

    2011-07-01

    Among the oldest symbiotic associations of plants are arbuscular mycorrhiza (AM) with fungi of the phylum Glomeromycota. Although many of the symbiotic signaling components have been identified on the side of the plant, AM fungi have long evaded genetic analysis owing to their strict biotrophy and their exceptional genetics. Recently, the identification of the fungal symbiosis signal (Myc factor) and of a corresponding Myc factor receptor, and new insights into AM fungal genetics, have opened new avenues to address early communication and functional aspects of AM symbiosis. These advances will pave the way for breeding programs towards adapted AM fungi for crop production, and will shed light on the ecology and evolution of this remarkably successful symbiosis. Copyright © 2011. Published by Elsevier Ltd.

  16. [Effects of environmental pollutants on arbuscular mycorrhiza formation and function].

    Science.gov (United States)

    Wang, Shuguang; Feng, Zhaozhong; Wang, Xiaoke

    2006-07-01

    Arbuscular mycorrhiza (AM) possesses the characteristics of both microbe and plant. Considerable attention has been focused on the use of AM in the remediation of polluted soil, but AM could be poisoned by pollutants when exposed to polluted soil, and thus, the significance of its application might be reduced. Therefore, how to reduce the negative effects of pollutants on AM is an issue to be considered in remedying polluted soil by AM. This paper briefly reviewed the effects of different organic and inorganic pollutants on AM structure, formation and function, and discussed the possible mechanisms. Both organic and inorganic pollutants could have detrimental effects on AM structure, formation and function, such as low spore germination, colonization rate, and hyphal growth. Organic pollutants indirectly affect the activity of AM fungi through affecting the carbohydrates allocation from plant to the fungi, while heavy metals directly inhibited the activity of AM fungi.

  17. The role of arbuscular mycorrhizas in reducing soil nutrient loss.

    Science.gov (United States)

    Cavagnaro, Timothy R; Bender, S Franz; Asghari, Hamid R; Heijden, Marcel G A van der

    2015-05-01

    Substantial amounts of nutrients are lost from soils via leaching and as gaseous emissions. These losses can be environmentally damaging and expensive in terms of lost agricultural production. Plants have evolved many traits to optimize nutrient acquisition, including the formation of arbuscular mycorrhizas (AM), associations of plant roots with fungi that acquire soil nutrients. There is emerging evidence that AM have the ability to reduce nutrient loss from soils by enlarging the nutrient interception zone and preventing nutrient loss after rain-induced leaching events. Until recently, this important ecosystem service of AM had been largely overlooked. Here we review the role of AM in reducing nutrient loss and conclude that this role cannot be ignored if we are to increase global food production in an environmentally sustainable manner. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Morphological and molecular characterization of selected Ramaria mycorrhizae.

    Science.gov (United States)

    Nouhra, Eduardo R; Horton, Thomas R; Cazares, Efren; Castellano, Michael

    2005-01-01

    Ramaria species are conspicuous mycorrhizal symbionts of conifers in the Pacific Northwest. Here we collected and identified sporocarps and associated ectomycorrhizae of Ramaria acrisiccescens Marr & Stuntz, R. cyaneigranosa Marr & Stuntz, R. sandaracina Marr & Stuntz, R. celerivirescens Marr & Stuntz, and R. flavobrunnescens var. aromatica Marr & Stuntz. An internal transcribed spacer (ITS)- restriction fragment length polymorphism pattern was observed for each of the Ramaria species and used as a diagnostic tool to support the identification of mycorrhizae occurring in mats below the sporocarps. We provide a description of ectomycorrhizae of Ramaria, which exhibit similar macro- and microscopic characteristics such as ramification pattern, coloration, abundance of mycelial strands and emanating hyphae, mantle morphology and chemical reactions of mantle and mycelial strands with KOH, FeSO4 and Melzer's reagent. Sequences of the ITS region for each of the species are deposited in the GenBank.

  19. Investigation of dryland wheat (Triticum aestivum L. cv. Azar 2 plants response to symbiosis with arbuscular mycorrhiza and mycorrhiza like fungi under different levels of drought stress

    Directory of Open Access Journals (Sweden)

    Y. Yaghoubian

    2016-05-01

    Full Text Available In order to evaluate arbuscular mycorrhiza (Glomuss mossea and mycorrhiza-like (Piriformospora indica effects on yield, yield components and some morphological (cv. Azar 2 traits of wheat (Triticum aestivum L. under water deficit stress, a pot experiment was conducted as factorial experiment based on completely randomized design with four replications. Treatments were drought stress at three levels (FC, -5 and -10 bar and fungi inoculation at four levels (mycorrhiza (AM, mycorrhiza-like (MLF and co-inoculation of AM+MLF and control. Results showed that the water stress significantly decreased 1000-grain weight, spike harvest index, fertility percent of spike, plant height, peduncle and extrusion length and colonization percent while grain density per spike markedly increased. Fungi inoculation significantly improved all studied traits except harvest index, 1000-grain weight and root colonization. Co-inoculation of AM and MLF had the best performance in terms of all mentioned parameters. Interaction effects of fungi and water stress was significant on grain and biological yield, spike and grain number and positively affected by fungi inoculation. Among fungi treatments, however, co-inoculation of AM+MLF had the best performance and recommended for both stress and non stress conditions.

  20. Effect of mycorrhiza on growth criteria and phosphorus nutrition of lettuce (Lactuca sativa L. under different phosphorus application rates

    Directory of Open Access Journals (Sweden)

    S. Fatih Ergin

    2016-10-01

    Full Text Available In this study, effect of mycorrhiza on growth criteria and phosphorus nutrition of lettuce (Lactuca sativa L. under different phosphorus fertilization rates were investigated. Phosphorus were added into growing media as 0, 50, 100 and 200 mg P2O5/kg with and without mycorrhiza applications. Phosphorus applications significantly increased yield criteria of lettuce according to the control treatment statistically. Mycorrhiza application also significantly increased plant diameter, plant dry weight and phosphor uptake by plant. The highest phosphorus uptakes by plants were determined in 200 mg P2O5/kg treatments as 88.8 mg P/pot with mycorrhiza and 83.1 mg P/pot without mycorrhiza application. In the control at 0 doses of phosphorus with mycorrhiza treatment, phosphorus uptake (69.9 mg P/pot, edible weight (84.36 g, dry weight (8.64 g and leaf number (28 of lettuce were higher than that (47.7 mg P/pot, 59.33 g, 6.75 g and 20, respectively in the control without mycorrhiza application. It was determined that mycorrhiza had positive effect on growth criteria and phosphorus nutrition by lettuce plant, and this effect decreased at higher phosphorus application rates.

  1. Effects of arbuscular mycorrhiza inoculation on growth and yield of tomato (Lycopersicum esculentum Mill. under salinity stress

    Directory of Open Access Journals (Sweden)

    D.R.R. Damaiyanti

    2015-10-01

    Full Text Available Objective of the research was to study the effect mycorrhiza on growth and yield of tomato. The experiment was conducted in screen house 14 m x 10.5 m, in Pasuruan on November 2013 until March 2014, The experiment was conducted as a factorial randomized complete design. The first factor was dose of mycorrhiza (without mycorrhiza, 5 g mycorrhiza, 10 g mycorrhiza, and 20 g mycorrhiza. The second factor was the salinity stress level (without NaCl, 2500 ppm NaCl, 5000 ppm NaCl, and 7500 ppm NaCl. The results showed that salinity stress at the level 7500 ppm decreased the amount of fruit by 30.84% and fresh weight per hectare decreased by 51.72%. Mycorrhizal application was not able to increase the growth and yield in saline stress conditions; it was shown by the level of infection and the number of spores on the roots of tomato plants lower the salinity level 5000 ppm and 7500 ppm. But separately, application of 20 g mycorrhiza enhanced plant growth, such as plant height, leaf area, leaf number and proline. Application of 20 g mycorrhiza increased the yield by 35.99%.

  2. Morphological characterization of the mycorrhiza formed by Helianthemum almeriense Pau with Terfezia claveryi Chatin and Picoa lefebvrei (Pat.) Maire.

    Science.gov (United States)

    Gutiérrez, A; Morte, A; Honrubia, M

    2003-12-01

    This work presents the first anatomical description of the mycorrhizal systems of Helianthemum almeriense, and of the structure and ultrastructure of the mycorrhizae formed by this plant species with the ascomycetes Terfezia claveryi and Picoa lefebvrei. Four different mycorrhizal systems are described, the club-shaped mycorrhiza being the most abundant. The type of mycorrhiza formed depended on the mycorrhiza culture conditions, but not on the fungal species. For both fungal species, H. almeriense formed an endomycorrhiza in natural field conditions, an ecto- and ectendomycorrhiza without a sheath in pot cultures, and an ectomycorrhiza with a characteristic sheath and Hartig net in in vitro cultures. This is the first report of a typical sheath in Helianthemum-desert truffle mycorrhizal associations. The results support the idea that culture conditions can induce changes in mycorrhiza morphology and that there is no clear barrier between the two main types of mycorrhiza organization in Helianthemum species. The ultrastructural study confirmed the regular presence of T. claveryi intracellular hyphae in direct contact with the host wall, a localization which seems to be a characteristic of the T. claveryi mycorrhiza organization. The P. lefebvrei mycorrhiza organization was characterized by intracellular hyphae with large amounts of electron-dense globules, probably with a lipidic content, and a warty ornamentation on the wall of the root external hyphae.

  3. Production of fungal and bacterial growth modulating secondary metabolites is widespread among mycorrhiza-associated streptomycetes

    Science.gov (United States)

    2012-01-01

    Background Studies on mycorrhiza associated bacteria suggest that bacterial-fungal interactions play important roles during mycorrhiza formation and affect plant health. We surveyed Streptomyces Actinobacteria, known as antibiotic producers and antagonists of fungi, from Norway spruce mycorrhizas with predominantly Piloderma species as the fungal partner. Results Fifteen Streptomyces isolates exhibited substantial variation in inhibition of tested mycorrhizal and plant pathogenic fungi (Amanita muscaria, Fusarium oxysporum, Hebeloma cylindrosporum, Heterobasidion abietinum, Heterobasidion annosum, Laccaria bicolor, Piloderma croceum). The growth of the mycorrhiza-forming fungus Laccaria bicolor was stimulated by some of the streptomycetes, and Piloderma croceum was only moderately affected. Bacteria responded to the streptomycetes differently than the fungi. For instance the strain Streptomyces sp. AcM11, which inhibited most tested fungi, was less inhibitory to bacteria than other tested streptomycetes. The determined patterns of Streptomyces-microbe interactions were associated with distinct patterns of secondary metabolite production. Notably, potentially novel metabolites were produced by strains that were less antagonistic to fungi. Most of the identified metabolites were antibiotics (e.g. cycloheximide, actiphenol) and siderophores (e.g. ferulic acid, desferroxiamines). Plant disease resistance was activated by a single streptomycete strain only. Conclusions Mycorrhiza associated streptomycetes appear to have an important role in inhibiting the growth of fungi and bacteria. Additionally, our study indicates that the Streptomyces strains, which are not general antagonists of fungi, may produce still un-described metabolites. PMID:22852578

  4. Production of fungal and bacterial growth modulating secondary metabolites is widespread among mycorrhiza-associated streptomycetes

    Directory of Open Access Journals (Sweden)

    Schrey Silvia D

    2012-08-01

    Full Text Available Abstract Background Studies on mycorrhiza associated bacteria suggest that bacterial-fungal interactions play important roles during mycorrhiza formation and affect plant health. We surveyed Streptomyces Actinobacteria, known as antibiotic producers and antagonists of fungi, from Norway spruce mycorrhizas with predominantly Piloderma species as the fungal partner. Results Fifteen Streptomyces isolates exhibited substantial variation in inhibition of tested mycorrhizal and plant pathogenic fungi (Amanita muscaria, Fusarium oxysporum, Hebeloma cylindrosporum, Heterobasidion abietinum, Heterobasidion annosum, Laccaria bicolor, Piloderma croceum. The growth of the mycorrhiza-forming fungus Laccaria bicolor was stimulated by some of the streptomycetes, and Piloderma croceum was only moderately affected. Bacteria responded to the streptomycetes differently than the fungi. For instance the strain Streptomyces sp. AcM11, which inhibited most tested fungi, was less inhibitory to bacteria than other tested streptomycetes. The determined patterns of Streptomyces-microbe interactions were associated with distinct patterns of secondary metabolite production. Notably, potentially novel metabolites were produced by strains that were less antagonistic to fungi. Most of the identified metabolites were antibiotics (e.g. cycloheximide, actiphenol and siderophores (e.g. ferulic acid, desferroxiamines. Plant disease resistance was activated by a single streptomycete strain only. Conclusions Mycorrhiza associated streptomycetes appear to have an important role in inhibiting the growth of fungi and bacteria. Additionally, our study indicates that the Streptomyces strains, which are not general antagonists of fungi, may produce still un-described metabolites.

  5. Effect of mycorrhizas application on plant growth and nutrient uptake in cucumber production under field conditions

    Energy Technology Data Exchange (ETDEWEB)

    Ortas, I.

    2010-07-01

    Mycorrhizas application in horticultural production in the Eastern Mediterranean region of Turkey has been studied under field conditions for several years. The effects of different arbuscular mycorrhizal fungi (AMF) have been evaluated under field conditions for cucumber production. The parameters measured were seedling survival, plant growth and yield, and root colonization. In 1998 and 1999, Glomus mosseae and Glomus etunicatum inoculated cucumber seedlings were treated with and without P (100 kg P2O5 ha-1) application. A second experiment was set up to evaluate the response of cucumber to the inoculation with a consortia of indigenous mycorrhizae, G. mosseae, G. etunicatum, Glomus clarum, Glomus caledonium and a mixture of these four species. Inoculated and control non inoculated cucumber seedlings were established under field conditions in 1998, 2001, 2002 and 2004. Seedling quality, seedling survival under field conditions and yield response to mycorrhiza were tested. Fruits were harvested periodically; at blossom, plant leaves and root samples were taken for nutrient content and mycorrhizal colonization analysis respectively. The field experiment results showed that mycorrhiza inoculation significantly increased cucumber seedling survival, fruit yield, P and Zn shoot concentrations. Indigenous mycorrhiza inoculum was successful in colonizing plant roots and resulted in better plant growth and yield. The relative effectiveness of each of the inocula tested was not consistent in the different experiments, although inoculated plants always grew better than control no inoculated. The most relevant result for growers was the increased survival of seedlings. (Author) 20 refs.

  6. Arbuscular mycorrhiza reduces phytoextraction of uranium, thorium and other elements from phosphate rock

    DEFF Research Database (Denmark)

    Roos, Per; Jakobsen, Iver

    2008-01-01

    Uptake of metals from uranium-rich phosphate rock was studied in Medicago truncatula plants grown in symbiosis with the arbuscular mycorrhizal fungus Glomus intraradices or in the absence of mycorrhizas. Shoot concentrations of uranium and thorium were lower in mycorrhizal than in non-mycorrhizal......Uptake of metals from uranium-rich phosphate rock was studied in Medicago truncatula plants grown in symbiosis with the arbuscular mycorrhizal fungus Glomus intraradices or in the absence of mycorrhizas. Shoot concentrations of uranium and thorium were lower in mycorrhizal than in non......-mycorrhizal plants and root-to-shoot ratio of most metals was increased by mycorrhizas. This protective role of mycorrhizas was observed even at very high supplies of phosphate rock. In contrast, phosphorus uptake was similar at all levels of phosphate rock, suggesting that the P was unavailable to the plant......-fungus uptake systems. The results support the role of arbuscular mycorrhiza as being an important component in phytostabilization of uranium. This is the first study to report on mycorrhizal effect and the uptake and root-to-shoot transfer of thorium from phosphate rock. (c) 2007 Elsevier Ltd. All rights...

  7. Production of fungal and bacterial growth modulating secondary metabolites is widespread among mycorrhiza-associated streptomycetes.

    Science.gov (United States)

    Schrey, Silvia D; Erkenbrack, Eric; Früh, Elisabeth; Fengler, Svenja; Hommel, Kerstin; Horlacher, Nadine; Schulz, Dirk; Ecke, Margret; Kulik, Andreas; Fiedler, Hans-Peter; Hampp, Rüdiger; Tarkka, Mika T

    2012-08-02

    Studies on mycorrhiza associated bacteria suggest that bacterial-fungal interactions play important roles during mycorrhiza formation and affect plant health. We surveyed Streptomyces Actinobacteria, known as antibiotic producers and antagonists of fungi, from Norway spruce mycorrhizas with predominantly Piloderma species as the fungal partner. Fifteen Streptomyces isolates exhibited substantial variation in inhibition of tested mycorrhizal and plant pathogenic fungi (Amanita muscaria, Fusarium oxysporum, Hebeloma cylindrosporum, Heterobasidion abietinum, Heterobasidion annosum, Laccaria bicolor, Piloderma croceum). The growth of the mycorrhiza-forming fungus Laccaria bicolor was stimulated by some of the streptomycetes, and Piloderma croceum was only moderately affected. Bacteria responded to the streptomycetes differently than the fungi. For instance the strain Streptomyces sp. AcM11, which inhibited most tested fungi, was less inhibitory to bacteria than other tested streptomycetes. The determined patterns of Streptomyces-microbe interactions were associated with distinct patterns of secondary metabolite production. Notably, potentially novel metabolites were produced by strains that were less antagonistic to fungi. Most of the identified metabolites were antibiotics (e.g. cycloheximide, actiphenol) and siderophores (e.g. ferulic acid, desferroxiamines). Plant disease resistance was activated by a single streptomycete strain only. Mycorrhiza associated streptomycetes appear to have an important role in inhibiting the growth of fungi and bacteria. Additionally, our study indicates that the Streptomyces strains, which are not general antagonists of fungi, may produce still un-described metabolites.

  8. Mycorrhizal diversity in Apostasia (Orchidaceae) indicates the origin and evolution of orchid mycorrhiza.

    Science.gov (United States)

    Yukawa, Tomohisa; Ogura-Tsujita, Yuki; Shefferson, Richard P; Yokoyama, Jun

    2009-11-01

    We demonstrated that "orchid mycorrhiza," a specialized mycorrhizal type, appeared in the common ancestor of the largest plant family Orchidaceae and that the fungal partner shifted from Glomeromycota to a particular clade of Basidiomycota in association with this character evolution. Several unique mycorrhizal characteristics may have contributed to the diversification of the family. However, the origin of orchid mycorrhiza and the diversity of mycobionts across orchid lineages still remain obscure. In this study, we investigated the mycorrhizae of five Apostasia taxa, members of the earliest-diverging clade of Orchidaceae. The results of molecular identification using nrDNA ITS and LSU regions showed that Apostasia mycorrhizal fungi belong to families Botryobasidiaceae and Ceratobasidiaceae, which fall within the order Cantharellales of Basidiomycota. Most major clades in Orchidaceae also form mycorrhizae with members of Cantharellales, while the sister group and other closely related groups to Orchidaceae (i.e., Asparagales except for orchids and the "commelinid" families) ubiquitously form symbioses with Glomeromycota to form arbuscular mycorrhizae. This pattern of symbiosis indicates that a major shift in fungal partner occurred in the common ancestor of the Orchidaceae.

  9. Mycorrhizas alter nitrogen acquisition by the terrestrial orchid Cymbidium goeringii.

    Science.gov (United States)

    Wu, Jianrong; Ma, Huancheng; Xu, Xingliang; Qiao, Na; Guo, Shitan; Liu, Fang; Zhang, Donghua; Zhou, Liping

    2013-06-01

    Orchid mycorrhizas exhibit a unique type of mycorrhizal symbiosis that occurs between fungi and plants of the family Orchidaceae. In general, the roots of orchids are typically coarse compared with those of other plant species, leading to a considerably low surface area to volume ratio. As a result, orchids are often ill-adapted for direct nutrient acquisition from the soil and so mycorrhizal associations are important. However, the role of the fungal partners in the acquisition of inorganic and organic N by terrestrial orchids has yet to be clarified. Inorganic and amino acid N uptake by non-mycorrhizal and mycorrhizal Cymbidium goeringii seedlings, which were grown in pots in a greenhouse, was investigated using a (15)N-labelling technique in which the tracer was injected at two different soil depths, 2·5 cm or 7·5 cm. Mycorrhizal C. goeringii seedlings were obtained by inoculation with three different mycorrhizal strains isolated from the roots of wild terrestrial orchids (two C. goeringii and one C. sinense). Non-mycorrhizal C. goeringii primarily took up NO3(-) from tracers injected at 2·5-cm soil depth, whereas C. goeringii inoculated with all three mycorrhiza primarily took up NH4(+) injected at the same depth. Inoculation of the mycorrhizal strain MLX102 (isolated from adult C. sinense) on C. goeringii roots only significantly increased the below-ground biomass of the C. goeringii; however, it enhanced (15)NH4(+) uptake by C. goeringii at 2·5-cm soil depth. Compared to the uptake of tracers injected at 2·5-cm soil depth, the MLX102 fungal strain strongly enhanced glycine-N uptake by C. goeringii from tracers injected at 7·5-cm soil depth. Cymbidium goeringii inoculated with CLB113 and MLX102 fungal strains demonstrated a similar N uptake pattern to tracers injected at 2·5-cm soil depth. These findings demonstrate that mycorrhizal fungi are able to switch the primary N source uptake of a terrestrial orchid, in this case C. goeringii, from NO3(-) to NH

  10. Changes in mycorrhiza development in maize induced by crop management practices

    DEFF Research Database (Denmark)

    Gavito, M.E.; Miller, M.H.

    1998-01-01

    mays L.) or a non-host (canola, Brassica napus L.) crop, and all of them with maize for the second year. Tillage and P fertilization treatments were applied to the plots in the second year. Mycorrhiza development in maize was measured in pot culture bioassays conducted before planting and after harvest...... of the previous and the subsequent crops, and in the field during the second crop season. Previous cropping of a soil with canola (Brassica napus L.), a non-host plant species, delayed mycorrhiza development of maize in a bioassay conducted with that soil in comparison with a previous cropping cycle with maize...... (Zea mays L.) or with the original plant species in the field site, bromegrass (Bromus inermis Leys.) and alfalfa (Medicago sativa L.). The delay in mycorrhiza development after cropping with canola was also observed in samples taken from the field and in a bioassay, both conducted at the beginning...

  11. Heavy metal distribution in Suillus luteus mycorrhizas - as revealed by micro-PIXE analysis

    Science.gov (United States)

    Turnau, K.; Przybyłowicz, W. J.; Mesjasz-Przybyłowicz, J.

    2001-07-01

    Suillus luteus/Pinus sylvestris mycorrhizas, collected from zinc wastes in Southern Poland, were selected as potential biofilters on the basis of earlier studies carried out with energy dispersive spectrometry (EDS) microanalytical system coupled to scanning electron microscope (SEM) and transmission electron microscope (TEM). Using the National Accelerator Centre (NAC) nuclear microprobe, elemental concentrations in the ectomycorrhiza parts were for the first time estimated quantitatively. Micro-proton-induced X-ray emission (PIXE) true elemental maps from freeze-dried and chemically fixed mycorrhizas revealed strong accumulation of Ca, Fe, Zn and Pb within the fungal mantle and in the rhizomorph. Vascular tissue was enriched with P, S and K, while high concentrations of Si and Cl were present in the endodermis. Cu was the only element showing elevated concentrations in the cortex region. Elemental losses and redistributions were found in mycorrhizas prepared by chemical fixation. Some problems related to elemental imaging are discussed.

  12. Sex-specific responses to mycorrhiza in a dioecious species.

    Science.gov (United States)

    Varga, Sandra; Kytöviita, Minna-Maarit

    2008-10-01

    In most studies about dioecious plants, the role of arbuscular mycorrhizae (AM) and the potential sex-specific differences between the plant hosts have been overlooked. Because plant sexes frequently differ in drought tolerance and AM fungal colonization provides higher resistance to drought, we investigated whether the relation of mycorrhizal fungi with either male or female Antennaria dioica plants differs using a factorial experiment. We hypothesized that because AM usually increase growth rate and male plants usually grow larger than females, males should gain more benefit from the mycorrhizal symbiosis in terms of mineral nutrition and water supply. Because of higher demands of carbohydrates (C) in males, we expected males to allocate less C resources to the mycorrhizal fungus so that the associated fungi should benefit less of the association with males. In contrast to our initial hypothesis, the male plants, although faster growing under drought, did not gain more symbiosis-mediated benefits than did the females, and both sexes seemed to provide resources equally to their fungal symbiont. Therefore, we conclude that the two plant sexual morphs provide equal amounts of C to their fungal root symbionts and that they can gain specific benefits from the symbiosis, which, however, depend on soil water availability.

  13. [Structure and function of arbuscular mycorrhiza: a review].

    Science.gov (United States)

    Tian, Mi; Chen, Ying-long; Li, Min; Liu, Run-jin

    2013-08-01

    Arbuscular mycorrhiza (AM) is one of the most widely distributed and the most important mutualistic symbionts in terrestrial ecosystems, playing a significant role in enhancing plant resistance to stresses, remediating polluted environments, and maintaining ecosystem stabilization and sustainable productivity. The structural characteristics of AM are the main indicators determining the mycorrhizal formation in root system, and have close relations to the mycorrhizal functions. This paper summarized the structural characteristics of arbuscules, vesicles, mycelia and invasion points of AM, and analyzed the relationships between the Arum (A) type arbuscules, Paris (P) type arbuscules, vesicles, and external mycelia and their functions in improving plant nutrient acquisition and growth, enhancing plant resistance to drought, waterlogging, salinity, high temperature, diseases, heavy metals toxicity, and promoting toxic organic substances decomposition and polluted and degraded soil remediation. The factors affecting the AM structure and functions as well as the action mechanisms of mycorrhizal functions were also discussed. This review would provide a basis for the systemic study of AM structural characteristics and functional mechanisms and for evaluating and screening efficient AM fungal species.

  14. Arbuscular mycorrhiza effects on plant performance under osmotic stress.

    Science.gov (United States)

    Santander, Christian; Aroca, Ricardo; Ruiz-Lozano, Juan Manuel; Olave, Jorge; Cartes, Paula; Borie, Fernando; Cornejo, Pablo

    2017-06-25

    At present, drought and soil salinity are among the most severe environmental stresses that affect the growth of plants through marked reduction of water uptake which lowers water potential, leading to osmotic stress. In general, osmotic stress causes a series of morphological, physiological, biochemical, and molecular changes that affect plant performance. Several studies have found that diverse types of soil microorganisms improve plant growth, especially when plants are under stressful conditions. Most important are the arbuscular mycorrhizal fungi (AMF) which form arbuscular mycorrhizas (AM) with approximately 80% of plant species and are present in almost all terrestrial ecosystems. Beyond the well-known role of AM in improving plant nutrient uptake, the contributions of AM to plants coping with osmotic stress merit analysis. With this review, we describe the principal direct and indirect mechanisms by which AM modify plant responses to osmotic stress, highlighting the role of AM in photosynthetic activity, water use efficiency, osmoprotectant production, antioxidant activities, and gene expression. We also discuss the potential for using AMF to improve plant performance under osmotic stress conditions and the lines of research needed to optimize AM use in plant production.

  15. Cell and developmental biology of arbuscular mycorrhiza symbiosis.

    Science.gov (United States)

    Gutjahr, Caroline; Parniske, Martin

    2013-01-01

    The default mineral nutrient acquisition strategy of land plants is the symbiosis with arbuscular mycorrhiza (AM) fungi. Research into the cell and developmental biology of AM revealed fascinating insights into the plasticity of plant cell development and of interorganismic communication. It is driven by the prospect of increased exploitation of AM benefits for sustainable agriculture. The plant cell developmental program for intracellular accommodation of AM fungi is activated by a genetically defined signaling pathway involving calcium spiking in the nucleus as second messenger. Calcium spiking is triggered by chitooligosaccharides released by AM fungi that are probably perceived via LysM domain receptor kinases. Fungal infection and calcium spiking are spatiotemporally coordinated, and only cells committed to accommodating the fungus undergo high-frequency spiking. Delivery of mineral nutrients by AM fungi occurs at tree-shaped hyphal structures, the arbuscules, in plant cortical cells. Nutrients are taken up at a plant-derived periarbuscular membrane, which surrounds fungal hyphae and carries a specific transporter composition that is of direct importance for symbiotic efficiency. An elegant study has unveiled a new and unexpected mechanism for specific protein localization to the periarbuscular membrane, which relies on the timing of gene expression to synchronize protein biosynthesis with a redirection of secretion. The control of AM development by phytohormones is currently subject to active investigation and has led to the rediscovery of strigolactones. Nearly all tested phytohormones regulate AM development, and major insights into the mechanisms of this regulation are expected in the near future.

  16. Arbuscular mycorrhiza: the mother of plant root endosymbioses.

    Science.gov (United States)

    Parniske, Martin

    2008-10-01

    Arbuscular mycorrhiza (AM), a symbiosis between plants and members of an ancient phylum of fungi, the Glomeromycota, improves the supply of water and nutrients, such as phosphate and nitrogen, to the host plant. In return, up to 20% of plant-fixed carbon is transferred to the fungus. Nutrient transport occurs through symbiotic structures inside plant root cells known as arbuscules. AM development is accompanied by an exchange of signalling molecules between the symbionts. A novel class of plant hormones known as strigolactones are exuded by the plant roots. On the one hand, strigolactones stimulate fungal metabolism and branching. On the other hand, they also trigger seed germination of parasitic plants. Fungi release signalling molecules, in the form of 'Myc factors' that trigger symbiotic root responses. Plant genes required for AM development have been characterized. During evolution, the genetic programme for AM has been recruited for other plant root symbioses: functional adaptation of a plant receptor kinase that is essential for AM symbiosis paved the way for nitrogen-fixing bacteria to form intracellular symbioses with plant cells.

  17. Lipid transfer from plants to arbuscular mycorrhiza fungi

    Science.gov (United States)

    Keymer, Andreas; Pimprikar, Priya; Wewer, Vera; Huber, Claudia; Brands, Mathias; Bucerius, Simone L; Delaux, Pierre-Marc; Klingl, Verena; von Röpenack-Lahaye, Edda; Wang, Trevor L; Eisenreich, Wolfgang; Dörmann, Peter; Parniske, Martin; Gutjahr, Caroline

    2017-01-01

    Arbuscular mycorrhiza (AM) symbioses contribute to global carbon cycles as plant hosts divert up to 20% of photosynthate to the obligate biotrophic fungi. Previous studies suggested carbohydrates as the only form of carbon transferred to the fungi. However, de novo fatty acid (FA) synthesis has not been observed in AM fungi in absence of the plant. In a forward genetic approach, we identified two Lotus japonicus mutants defective in AM-specific paralogs of lipid biosynthesis genes (KASI and GPAT6). These mutants perturb fungal development and accumulation of emblematic fungal 16:1ω5 FAs. Using isotopolog profiling we demonstrate that 13C patterns of fungal FAs recapitulate those of wild-type hosts, indicating cross-kingdom lipid transfer from plants to fungi. This transfer of labelled FAs was not observed for the AM-specific lipid biosynthesis mutants. Thus, growth and development of beneficial AM fungi is not only fueled by sugars but depends on lipid transfer from plant hosts. DOI: http://dx.doi.org/10.7554/eLife.29107.001 PMID:28726631

  18. Growing poplars for research with and without mycorrhizas

    Directory of Open Access Journals (Sweden)

    Anna eMüller

    2013-08-01

    Full Text Available During the last decades the importance of the genus Populus increased because the poplar genome has been sequenced and molecular tools for basic research are available. Furthermore, poplar species occur in different habitats and harbour large genetic variation, which can be exploited for economic applications and for increasing our knowledge on the basic molecular mechanisms of the woody life style. Poplars are, therefore, employed to unravel the molecular mechanisms of wood formation, stress tolerance, tree nutrition and interaction with other organisms such as pathogens or mycorrhiza. The basis of these investigations is the reproducible production of homogeneous plant material. In this method paper we describe techniques and growth conditions for the in vitro propagation of different poplar species (Populus × canescens, P. trichocarpa, P. tremula and P. euphratica and ectomycorrhizal fungi (Laccaria bicolor, Paxillus involutus as well as for their co-cultivation for ectomycorrhizal synthesis. Maintenance and plant preparation require different multiplication and rooting media. Growth systems to cultivate poplars under axenic conditions in agar and sand cultures with and without mycorrhizal fungi are described. Transfer of the plants from in vitro to in situ conditions is critical and hardening is important to prevent high mortality. Growth and vitality of the trees in vitro and outdoors with and without ectomycorrhizas are reported.

  19. Mycorrhiza alters the profile of root hairs in trifoliate orange.

    Science.gov (United States)

    Wu, Qiang-Sheng; Liu, Chun-Yan; Zhang, De-Jian; Zou, Ying-Ning; He, Xin-Hua; Wu, Qing-Hua

    2016-04-01

    Root hairs and arbuscular mycorrhiza (AM) coexist in root systems for nutrient and water absorption, but the relation between AM and root hairs is poorly known. A pot study was performed to evaluate the effects of four different AM fungi (AMF), namely, Claroideoglomus etunicatum, Diversispora versiformis, Funneliformis mosseae, and Rhizophagus intraradices on root hair development in trifoliate orange (Poncirus trifoliata) seedlings grown in sand. Mycorrhizal seedlings showed significantly higher root hair density than non-mycorrhizal seedlings, irrespective of AMF species. AMF inoculation generally significantly decreased root hair length in the first- and second-order lateral roots but increased it in the third- and fourth-order lateral roots. AMF colonization induced diverse responses in root hair diameter of different order lateral roots. Considerably greater concentrations of phosphorus (P), nitric oxide (NO), glucose, sucrose, indole-3-acetic acid (IAA), and methyl jasmonate (MeJA) were found in roots of AM seedlings than in non-AM seedlings. Levels of P, NO, carbohydrates, IAA, and MeJA in roots were correlated with AM formation and root hair development. These results suggest that AMF could alter the profile of root hairs in trifoliate orange through modulation of physiological activities. F. mosseae, which had the greatest positive effects, could represent an efficient AM fungus for increasing fruit yields or decreasing fertilizer inputs in citrus production.

  20. Diversity and evolution of ABC proteins in mycorrhiza-forming fungi.

    Science.gov (United States)

    Kovalchuk, Andriy; Kohler, Annegret; Martin, Francis; Asiegbu, Fred O

    2015-12-28

    Transporter proteins are predicted to have an important role in the mycorrhizal symbiosis, due to the fact that this type of an interaction between plants and fungi requires a continuous nutrient and signalling exchange. ABC transporters are one of the large groups of transporter proteins found both in plants and in fungi. The crucial role of plant ABC transporters in the formation of the mycorrhizal symbiosis has been demonstrated recently. Some of the fungal ABC transporter-encoding genes are also induced during the mycorrhiza formation. However, no experimental evidences of the direct involvement of fungal ABC transporters in this process are available so far. To facilitate the identification of fungal ABC proteins with a potential role in the establishment of the mycorrhizal symbiosis, we have performed an inventory of the ABC protein-encoding genes in the genomes of 25 species of mycorrhiza-forming fungi. We have identified, manually annotated and curated more than 1300 gene models of putative ABC protein-encoding genes. Out of those, more than 1000 models are predicted to encode functional proteins, whereas about 300 models represent gene fragments or putative pseudogenes. We have also performed the phylogenetic analysis of the identified sequences. The sets of ABC proteins in the mycorrhiza-forming species were compared to the related saprotrophic or plant-pathogenic fungal species. Our results demonstrate the high diversity of ABC genes in the genomes of mycorrhiza-forming fungi. Via comparison of transcriptomics data from different species, we have identified candidate groups of ABC transporters that might have a role in the process of the mycorrhiza formation. Results of our inventory will facilitate the identification of fungal transporters with a role in the mycorrhiza formation. We also provide the first data on ABC protein-coding genes for the phylum Glomeromycota and for orders Pezizales, Atheliales, Cantharellales and Sebacinales, contributing to

  1. Absorption of Some Nutrient as Affected by Mycorrhizae, Different Levels of Zinc and Drought Stress in Maize

    Directory of Open Access Journals (Sweden)

    N.A Sajedi

    2011-02-01

    Full Text Available Abstract In order to investigate absorption of some nutrient as affected by mycorrhizae, different levels of zinc and drought stress in maize (KSC 704, an experiment was carried out in research farm of Islamic Azad University–Arak in 2006-2007. The Experiment was conducted in factorial arrangement based on randomized complete block design with three replications. Treatments consist of irrigation levels: I1= %100, I2= %75 and I3= %50 crop water requirement, mycorrhiza fungus (Glumus intraradices at two levels (inoculation and non inoculation and zinc sulfate at three levels: 0, 25 and 45 kg ha-1. Results showed that drought stress increased absorption of nitrogen, potassium and protein percentage, but reduced absorption of phosphorous. Inoculation with mycorrhizae increased absorption of nutrients. Using of zinc sulfate increased absorption of nitrogen, potassium, phosphorous and protein percentage. Inoculation of mycorrhiza under drought stress had not significant effect on absorption of nutrients and protein percentage of grain. Using of zinc sulfate under drought stress increased absorption of nitrogen, potassium and protein percentage of grain but reduced absorption of phosphorous. interactions effects of mycorrhizae and zinc sulfate increased absorption of nutritional elements. The highest amounts of nitrogen and potassium absorption and protein percentage of grain were observed in combination of irrigation equal to 50% of crop water demand, mycorrhiza + 25 kg ha-1 zinc sulfate. The highest grain yield was observed from combination of optimum irrigation, without mycorrhiza + 45 kg ha-1 zinc sulfate. It was concluded that with irrigation equal to 75% water requirement + inoculation with mycorrhiza + 45kg ha-1 zinc sulfate optimum crop yield could be obtained. Keywords: Drought stress, Mycorrhiza, Nutrition of elements, Protein, Maize

  2. Soil Structure and Mycorrhizae Encourage Black Walnut Growth on Old Fields

    Science.gov (United States)

    Felix Jr. Ponder

    1979-01-01

    Examination of black walnut seedlings grown in forest and field soils showed all root systems were infected with mycorrhizae; the amount of infection was influenced by treatments. Mean height and dry weight of tops and roots were greater for seedlings grown in forest than field soil. Seedling height growth was not increased by disturbing either soil; but, root dry...

  3. Studies on Ectomycorrhizae—XV. Mycorrhizae formed by Rhizopogon luteolus on Pinus silvestris

    NARCIS (Netherlands)

    Uhl, M.

    1988-01-01

    The mycorrhizae of Rhizopogon luteolus on Pinus silvestris are comprehensively described. They are characterized by a coralloid habit, ochre to yellow colour, highly differentiated rhizomorphs, a two-layered mantle and a differentiated autofluorescence in mantle, Hartig net and rhizomorphs. The

  4. Relation of soil nutrients and light to prevalence of mycorrhizae on pine seedlings

    Science.gov (United States)

    Edward Hacskaylo; Albert G., Jr. Snow

    1959-01-01

    Odd relationships abound among the wonders of Nature. Just as men keep cows, some ants herd aphids. The bee pays Nature for its food by pollinating the flower. One symbiotic relationship that concerns foresters is the coupling of tree roots with certain fungi to form compound structures, part tree root and part fungus mycelium, which we call mycorrhizae.

  5. Effect of mycorrhiza symbiosis on the Nacl salinity in Sorghum bicolor

    African Journals Online (AJOL)

    Jane

    2011-08-01

    Aug 1, 2011 ... Mycorrhiza symbiosis appears between most of the vascular plants (more than. 80%) and a group of soil fungi belong to three branches of Basidiomycota, Ascomycota and Zygomycotina. (Harley and Smith, 1983). The result of this symbiosis is the fungi help in the absorption and transfer of nutrition to.

  6. Ondergrondse communicatie: de driehoeksrelatie gastheerplant, parasitaire plant en mycorrhiza-schimmel

    NARCIS (Netherlands)

    Kohlen, W.; Bouwmeester, H.J.

    2007-01-01

    De ontdekking van strigolactonen laat zien dat planten op grote schaal ondergronds communiceren. Planten produceren die strigolactonen niet om te communiceren met de parasitaire planten, maar met de mycorrhiza schimmels en mogelijk ook andere voor de plant nuttige organismen. De parasitaire planten

  7. Molecular Identification of Mycorrhizae of Cymbidium kanran (Orchidaceae) on Jeju Island, Korea.

    Science.gov (United States)

    Hong, Ji Won; Suh, Hyoungmin; Kim, Oh Hong; Lee, Nam Sook

    2015-12-01

    A fungal internal transcribed spacer region was used to identify the mycorrhizae of Cymbidium kanran. The family Russulaceae was found to be the most frequently occurring group in both root and soil samples. In phylogenetic analyses, the majority of the Russulaceae clones were clustered with Russula brevipes and R. cyanoxantha. Therefore, C. kanran may form symbiotic relationships with the genus Russula.

  8. Effects of metal lead on growth and mycorrhizae of an invasive plant species (Solidago canadensis L.).

    Science.gov (United States)

    Yang, Ruyi; Yu, Guodong; Tang, Jianjun; Chen, Xin

    2008-01-01

    It is less known whether and how soil metal lead (Pb) impacts the invasion of exotic plants. A greenhouse experiment was conducted to estimate the effects of lead on the growth and mycorrhizae of an invasive species (Solidago canadensis L.) in a microcosm system. Each microcosm unit was separated into HOST and TEST compartments by a replaceable mesh screen that allowed arbuscular mycorrhizal (AM) fungal hyphae rather than plant roots to grow into the TEST compartments. Three Pb levels (control, 300, and 600 mg/kg soil) were used in this study to simulate ambient soil and two pollution sites where S. canadensis grows. Mycorrhizal inoculum comprised five indigenous arbuscular mycorrhizal fungal species (Glomus mosseae, Glomus versiform, Glomus diaphanum, Glomus geosporum, and Glomus etunicatum). The 15N isotope tracer was used to quantify the mycorrhizally mediated nitrogen acquisition of plants. The results showed that S. canadensis was highly dependent on mycorrhizae. The Pb additions significantly decreased biomass and arbuscular mycorrhizal colonization (root length colonized, RLC%) but did not affect spore numbers, N (including total N and 15N) and P uptake. The facilitating efficiency of mycorrhizae on nutrient acquisition was promoted by Pb treatments. The Pb was mostly sequestered in belowground of plant (root and rhizome). The results suggest that the high efficiency of mycorrhizae on nutrient uptake might give S. canadensis a great advantage over native species in Pb polluted soils.

  9. DO ELEVATED CO2 AND N FERTILIZATION ALTER FINE ROOT-MYCORRHIZAE RELATIONSHIPS IN PINUS PONDEROSA?

    Science.gov (United States)

    Despite extensive studies on the response of plants to elevated CO2, climate change and N deposition, little is known about the response of roots and mycorrhizae in spite of their key role in plant water and nutrient acquisition. The effects of elevated CO2 and N fertilization on...

  10. Enhanced growth of multipurpose Calliandra (Calliandra calothyrsus) using arbuscular mycorrhiza fungi in Uganda.

    Science.gov (United States)

    Sebuliba, Esther; Nyeko, Phillip; Majaliwa, Mwanjalolo; Eilu, Gerald; Kizza, Charles Luswata; Ekwamu, Adipala

    2012-01-01

    This study was conducted to compare the effect of selected arbuscular mycorrhiza fungi genera and their application rates for enhanced Calliandra growth in Uganda. The performance of Calliandra under different types and rates of arbuscular mycorrhiza fungi inoculation was assessed in the greenhouse using sterilized Mabira soils. Four dominant genera were isolated from the rhizosphere of sorghum in the laboratory. Calliandra seeds were grown in pots and the seed coating method of application was used at concentrations of 0 spores, 30 spores and 50 spores. Each treatment was replicated three times. All Calliandra inoculated seedlings showed improved seedling growth (in terms of height and shoot dry matter weight) compared to the control (P mycorrhiza fungi mixture treated Calliandra at 50 spores rate. Glomus sp. and Acaulospora sp. had significant influence on the height of Calliandra, while AMF mixture performed best in terms of shoot dry weight (P mycorrhiza fungi for beneficial effects in the primary establishment of slow growing seedlings ensuring better survival and improved growth.

  11. Medicago truncatula gene responses specific to arbuscular mycorrhiza interactions with different species and genera of Glomeromycota.

    Science.gov (United States)

    Massoumou, M; van Tuinen, D; Chatagnier, O; Arnould, C; Brechenmacher, L; Sanchez, L; Selim, S; Gianinazzi, S; Gianinazzi-Pearson, V

    2007-05-01

    Plant genes exhibiting common responses to different arbuscular mycorrhizal (AM) fungi and not induced under other biological conditions have been sought for to identify specific markers for monitoring the AM symbiosis. A subset of 14 candidate Medicago truncatula genes was identified as being potentially mycorrhiza responsive in previous cDNA microarray analyses and exclusive to cDNA libraries derived from mycorrhizal root tissues. Transcriptional activity of the selected plant genes was compared during root interactions with seven AM fungi belonging to different species of Glomus, Acaulospora, Gigaspora, or Scutellospora, and under widely different biological conditions (mycorrhiza, phosphate fertilization, pathogenic/beneficial microbe interactions, incompatible plant genotype). Ten of the M. truncatula genes were commonly induced by all the tested AM fungal species, and all were activated by at least two fungi. Most of the plant genes were transcribed uniquely in mycorrhizal roots, and several were already active at the appressorium stage of fungal development. Novel data provide evidence that common recognition responses to phylogenetically different Glomeromycota exist in plants during events that are unique to mycorrhiza interactions. They indicate that plants should possess a mycorrhiza-specific genetic program which is comodulated by a broad spectrum of AM fungi.

  12. Enzymatic evidence for the key role of arginine in nitrogen translocation by arbuscular mycorrhiza fungi

    DEFF Research Database (Denmark)

    Cruz, C.; Egsgaard, Helge; Trujillo, C.

    2007-01-01

    Key enzymes of the urea cycle and N-15-labeling patterns of arginine (Arg) were measured to elucidate the involvement of Arg in nitrogen translocation by arbuscular mycorrhizal (AM) fungi. Mycorrhiza was established between transformed carrot (Daucus carota) roots and Glomus intraradices in two- ...

  13. Relación de las velocidades finales alcanzadas entre el Course Navette de 20 metros y el test de VAM-EVAL. Una propuesta para predecir la velocidad aeróbica máxima

    OpenAIRE

    García, Gastón; Secchi, Jeremías

    2013-01-01

    Introducción El propósito de este estudio fue proponer una tabla de corrección para la predicción de la velocidad aeróbica máxima (VAM) a partir del test de Course Navette de 20metros (CN-20m) en ambos sexos. Material y métodos Setenta y siete sujetos (46 hombres y 31 mujeres), estudiantes de educación física, participaron voluntariamente. Fueron evaluados en 3 ocasiones. En primer lugar se realizó la evaluación antropométrica en laboratorio. En las siguientes dos oportunidade...

  14. Effect of chemophytostabilization practices on arbuscular mycorrhiza colonization of Deschampsia cespitosa ecotype Warynski at different soil depths

    NARCIS (Netherlands)

    Gucwa-Przepióra, E.; Malkowski, E.; Sas-Nowosielska, A.; Kucharski, R.; Krzyzak, J.; Kita, A.; Römkens, P.F.A.M.

    2007-01-01

    The effects of chemophytostabilization practices on arbuscular mycorrhiza (AM) of Deschampsia cespitosa roots at different depths in soils highly contaminated with heavy metals were studied in field trials. Mycorrhizal parameters, including frequency of mycorrhization, intensity of root cortex

  15. Combined effects of arbuscular mycorrhizas and light on water uptake of the neotropical understory shrubs, Piper and Psychotria

    Science.gov (United States)

    Damond A. Kyllo; Virginia Velez; Melvin T. Tyree

    2003-01-01

    Root hydraulic conductance (Kr) was measured for five understory shrub species of the neotropical moist forest to determine the effects of arbuscular mycorrhizas (AM) for both carbon-rich and carbon-limited host plants.

  16. A quantitative and molecular examination of Tuber melanosporum mycorrhizae in Quercus ilex seedlings from different suppliers in Spain

    Directory of Open Access Journals (Sweden)

    P. Alvarado

    2013-07-01

    Full Text Available Aim of study: The aim of the work was to determine the degree of mycorrhization of Quercus ilex L. subsp. ballota (Desf. Samp. by the black truffle fungus T. melanosporum Vittad. by quantitative and molecular analyses.Area of study: seedlings inoculated by different Spanish suppliers.Material and methods: The internal transcribed spacers (ITS of mycorrhizae from different plants were amplified by nested PCR involving fluorescently-labelled primers, and the amplicons either directly sized by ARISA or analysed by TRFLP following their digestion with restriction endonucleases. TRFLP analysis distinguished between mycorrhizae of T. melanosporum, T. indicum Cooke & Massee and T. borchii Vittad., as suggested possible by virtual (in silico TRFLP analysis and real TRFLP analysis of the ascomata of these species.Main results: Significant differences between suppliers were detected in terms of the mean number of mycorrhizae established per plant and percentage mycorrhization. These results allowed the following quality standards for 2 year-old plants to be proposed: a good quality: >3000 mycorrhizae/plant, >40% mycorrhization, b medium (acceptable: >3000 mycorrhizae/plant, >30% mycorrhization, c low quality: <3000 mycorrhizae/plant or <30% mycorrhization, always supposing the mycorrhizae counted represent the species of interest as confirmed by the presence of its DNA and the absence of DNA belonging to contaminating species. Finally, a new microsatellite allelic map obtained from the analysis of several T. melanosporum populations across Spain was used to provide a tool capable of determining the geographic origin of the fungi used to inoculate plants.Research highlights: The proposed quality standards can be useful for the evaluation and certification of commercialized Q. ilex plants mycorrhized with T. melanosporum.Keywords: mycorrhiza; certification; truffle; TRFLP; fungi.

  17. Co-occurrence of Arum- and Paris-type morphologies of arbuscular mycorrhizae in cucumber and tomato.

    Science.gov (United States)

    Kubota, Mayumi; McGonigle, Terence P; Hyakumachi, Mitsuro

    2005-03-01

    Colonization by arbuscular mycorrhizal (AM) fungi was investigated in cucumber (Cucumis sativus), tomato (Lycopersicon esculentum) and Clethra barbinervis (Ericales) grown in field-collected soil known from previous studies to generate Paris-type arbuscular mycorrhizae in C. barbinervis. Spores of Paraglomus, Acaulospora, Glomus, and Gigaspora were found in the soil. Formation of hyphal coils and arbusculate coils of Paris-type mycorrhizae and of arbuscules of Arum-type mycorrhizae in roots raised in this soil in the growth chamber were compared with the detection of DNA of AM fungi from the same root systems using Glomales-specific primers. Only Paris-type mycorrhizae with extensive arbusculate coils developed in C. barbinervis, but cucumber and tomato developed both Paris- and Arum-types in the same root systems. Glomaceae and Archaeosporaceae and/or Paraglomaceae were detected strongly in the DNA from both cucumber and tomato roots, in which Arum-type mycorrhizae were observed. In contrast, DNA of Glomaceae was detected more sparingly in C. barbinervis, in which Paris-type mycorrhizae dominated. Acaulosporaceae and Gigasporaceae were strongly detected in the DNA from both C. barbinervis and tomato, whereas they were more weakly detected in cucumber. These results indicate that the morphology of colonization is strongly influenced by the selection of fungi to colonize the host plant from among those in the soil environment.

  18. Fractionation of Nitrogen Isotopes by Plants with Different Types of Mycorrhiza in Mountain Tundra Ecosystems

    Science.gov (United States)

    Buzin, Igor; Makarov, Mikhail; Maslov, Mikhail; Tiunov, Alexei

    2017-04-01

    We studied nitrogen concentration and nitrogen isotope composition in plants from four mountain tundra ecosystems in the Khibiny Mountains. The ecosystems consisted of a toposequence beginning with the shrub-lichen heath (SLH) on the ridge and upper slope, followed by the Betula nana dominated shrub heath (SH) on the middle slope, the cereal meadow (CM) on the lower slope and the sedge meadow (SM) at the bottom of the slope. The inorganic nitrogen concentration of the soils from the studied ecosystems were significantly different; the SLH soil was found to contain the minimum concentration of N-NH4+ and N-NO3- , while in the soils of the meadow ecosystems these concentrations were much higher. The concentration of nitrogen in leaves of the dominant plant species in all of the ecosystems is directly connected with the concentration of inorganic nitrogen in the soils, regardless of the plant's mycorrhizal symbiosis type. However, such a correlation is not apparent in the case of plant roots, especially for plant roots with ectomycorrhiza and ericoid mycorrhiza. The majority of plant species with these types of mycorrhiza in the SH and particularly in the CM were enriched in 15N in comparison with the SLH (such plants were not found within the SM). This could be due to several reasons: 1) the decreasing role of mycorrhiza in nitrogen consumption and therefore in the fractionation of isotopes in the relatively-N-enriched ecosystems; 2) the use of relatively-15N-enriched forms of nitrogen for plant nutrition in meadow ecosystems. This heavier nitrogen isotope composition in plant roots with ectomycorrhiza and ericoid mycorrhiza in ecosystems with available nitrogen enriched soils doesn't correspond to the classical idea of mycorrhiza decreasing participation in nitrogen plant nutrition. The analysis of the isotope composition of separate labile forms of nitrogen makes it possible to explain the phenomenon. Not all arbuscular mycorrhizal species within the sedge meadow

  19. Expression of early nodulin genes in alfalfa mycorrhizae indicates that signal transduction pathways used in forming arbuscular mycorrhizae and Rhizobium-induced nodules may be conserved

    Science.gov (United States)

    van Rhijn, P.; Fang, Y.; Galili, S.; Shaul, O.; Atzmon, N.; Wininger, S.; Eshed, Y.; Lum, M.; Li, Y.; To, V.; Fujishige, N.; Kapulnik, Y.; Hirsch, A. M.

    1997-01-01

    Transcripts for two genes expressed early in alfalfa nodule development (MsENOD40 and MsENOD2) are found in mycorrhizal roots, but not in noncolonized roots or in roots infected with the fungal pathogen Rhizoctonia solani. These same two early nodulin genes are expressed in uninoculated roots upon application of the cytokinin 6-benzylaminopurine. Correlated with the expression of the two early nodulin genes, we found that mycorrhizal roots contain higher levels of trans-zeatin riboside than nonmycorrhizal roots. These data suggest that there may be conservation of signal transduction pathways between the two symbioses—nitrogen-fixing nodules and phosphate-acquiring mycorrhizae. PMID:11038545

  20. Improvement of production of high-yield poplar varieties seedlings by mycorrhiza application

    Directory of Open Access Journals (Sweden)

    Galić Zoran A.

    2007-01-01

    Full Text Available Research related to the effects of treatment by mycorrhiza preparations Ectovit, Rhodovit (preparations Symbio-m Ltd., Czech Rep. and their combination on growth of four high-yield poplar clones of Populus deltoides and one variety of Populus x euramericana are presented in this paper. In order to make more accurate assessment of mycorrhiza effect, soil characteristics such as morphology, texture and chemical composition were determined. The study results indicate that mycorrhized cuttings had the same or the better survival in all the study clones compared to the control. The application of the preparation Ectovit and Rhodovit resulted averagely in the first class planting stock of all the study clones. The combination of the preparations Ectovit and Rhodovit produced averagely the first class planting stock only of the clone Populus x euramericana.

  1. Identification of genes and proteins involved in the regulation of orchid mycorrhiza

    OpenAIRE

    Rafael Borges da Silva Valadares

    2014-01-01

    Orchids are characterized by producing minute endosperm-lacking seeds, which depend on mycorrhizal fungi for germination and embryo development. Some aclorophyllous orchids remain dependent on the mycorrhizal association for carbon acquisition during their whole life history, whereasother orchids develop photosynthesis. Despite the biological significance of orchid mycorrhiza, gene expression studies are lacking. We have used different highthroughput approaches in order to understanding the m...

  2. Evaluation the morph physiological changes in wheat cultivars from the use of Mycorrhiza and Azospirillum

    Directory of Open Access Journals (Sweden)

    M Jiriaie

    2015-04-01

    Full Text Available Resolution nutrient requirements in crops by non-chemical resource are new approach in production the organic crops. In order to study evaluation the morph physiological changes in wheat cultivars from the use of Mycorrhiza and Azospirillum, an experiment was conducted in the research station of Shahid Chamran University of Ahvaz, Iran in 2012-13. The experimental design was factorial based on randomized complete blocks design with three replications. The treatments including of bacteria Azospirillum lipoferum in the two-level (non-inoculated seeds and inoculated seed, Mycorrhiza fungi in three levels (no use of strain and using strain Glomus intraradices and Glomus mossaae, and wheat cultivars in three levels, (Chamran, Dena and Behrang. The results had indicated a significant and positive effect of microorganisms use on wheat cultivars for most traits. So that cooperation of Mycorrhiza 7 to 33% and associative symbiosis of Azospirillum 7 to 29% improved traits. However, concurrent use, led to increase the use of biological fertilizers effects on morphological traits of wheat. But the greatest plant height (103 cm, grain protein concentration (12.58% and number of spikes per unit area (519 m2 was obtained from inoculation of C.V Dena seeds with Azospirillum and G. mossaae and the highest flag leaf length (29.33 cm, days to maturity (118 days, the yield of single plant (6.96 g and spike length (9.33 cm was obtained from inoculation of C.V Chamran seeds with Azospirillum and G. mossaae. Also the highest mycorrhizal dependency (32% and Growth response (47% was obtained from C.V Dena seeds with G. mossaae. So wheat nutrition with Azospirillum and Mycorrhiza can be been suitable replacement for chemical fertilizers.

  3. Arbuscular Mycorrhiza Stimulates Biological Nitrogen Fixation in Two Medicago spp. through Improved Phosphorus Acquisition

    Czech Academy of Sciences Publication Activity Database

    Püschel, David; Janoušková, M.; Voříšková, A.; Gryndlerová, Hana; Vosátka, M.; Jansa, Jan

    2017-01-01

    Roč. 8, MAR 27 (2017), s. 1-12, č. článku 390. ISSN 1664-462X R&D Projects: GA ČR GA15-05466S; GA MŠk(CZ) LK11224 Institutional support: RVO:61388971 Keywords : arbuscular mycorrhiza * nitrogen acquisition * phosphorus uptake Subject RIV: EE - Microbiology, Virology Impact factor: 4.298, year: 2016

  4. [Signal exchange between plants and Arbuscular Mycorrhizae fungi during the early stage of symbiosis - A review].

    Science.gov (United States)

    Duan, Qianqian; Yang, Xiaohong; Huang, Xianzhi

    2015-07-04

    Much is known about Arbuscular Mycorrhizae (AM), an important component of the ecosystem, whereas little is known about the signal exchange that allows mutual recognition and reprograming for the anticipated physical interaction. This review addresses the latest advances of signal exchange between plants and AM, including signal substances and their function, related genes and regulation function in the early stage of plant-fungal symbiosis.

  5. Influence of fertilization of nitrogen on the mycorrhiza-system of spruce

    Energy Technology Data Exchange (ETDEWEB)

    Haug, I.; Kottke, I.; Oberwinkler, F.; Horsch, F.; Filby, W.G.; Fund, N.; Gross, S.; Hanisch, B.; Kilz, E.; Seidel, A.

    1988-04-01

    A laboratory experiment was carried out with different nitrogen forms (NH/sub 4//sup +/, NO/sub 3//sup -/) and different nitrogen levels. For each nitrogen form three concentrations were chosen. Spruce seedlings inoculated with Pisolithus tinctorius or Amanita muscaria were placed in growth chambers with the different nitrogen-variants. After 7 weeks most seedlings in the high ammonium concentration were dead. There was no significant difference in the growth rate of the roots with exception of the high ammonium variant. The greatest total root length was reached in the low variants, also the highest amount of short roots. The shoot/root-ratio is positively correlated with the ammonium concentration. With increasing nitrate concentrations, the shoot/root-ratio also increases, but the differences are not significant. In the low and middle variants, there were well developed mycorrhizae with a hyphal mantle and a Hartig net. The greatest amount of mycorrhizae was found in the low nitrate variant. Light microscopic investigations revealed no differences in the structure of the mycorrhizae from the different variants. Quantitative analyses are not possible with the used method.

  6. Effect of combined inoculations of Rhizobium-Arbuscular Mycorrhiza in Leucaena leucocephala CV: Perú

    Directory of Open Access Journals (Sweden)

    Lázaro Jesús Ojeda Quintana

    2014-07-01

    Full Text Available The work was conducted at the Experimental Station of Soil and Fertilizer “Escambray” land of farmers and associated rural extension. The experimental design was randomized blocks, and treatments: Rizhobium loti V-4033 (Research Institute of Pastures and Forages, mycorrhizal fungi trainers, Rhizobium +mycorrhiza fungi trainers, nitrogen and total control. Inoculation with my corrhiza forming fungi was performed at 10 g/bag Certificate MicoFert Strain the Institute of Ecology and Systematics-3: Glomus spurcum, Topes de Collantes, 85 % colonization of rootlets, while the Rhizobium was inoculated in a dose of 50 g/kg of seed. Variant was nitrogen at 25 kg/ha of urea. The plots occupied 18m2 , with an area of 9 m2 evaluable. When the plants reached 7.5 months and an average height of 143.4 cm proceeded to make the Court of establishment and then four foliage cuts were made every 90 days. Each cut dry biomass yield, and phosphorus content was determined crude protein. The combined inoculation of Rhizobium and mycorrhiza fungi Makers increased the yield of dry biomass, and phosphorus content of crude protein. We conclude proposing the adoption of an alternative methodology using mycorrhiza formers Fungi and Rhizobium in Leucaena leucocephala as a way to increase the yield of dry biomass, decreasing mineral fertilization and contribute to environmental protection

  7. Abundance, diversity, and vitality of mycorrhizae of Scots pine (Pinus sylvestris L.) in lignite recultivation sites.

    Science.gov (United States)

    Münzenberger, B; Golldack, J; Ullrich, A; Schmincke, B; Hüttl, R F

    2004-07-01

    Scots pine (Pinus sylvestris L.) stands cover large areas in the Lusatian and the Middle German lignite mining districts. Due to adverse chemical substrate conditions, the root systems of the trees are restricted to the ameliorated top-spoil and the organic forest floor layers. To investigate functioning of fine root systems under the prevailing site factors, we studied mycorrhizal colonization rate and frequency as well as mycorrhizal diversity, vitality and growth phases in Scots pine ecosystems along a chronosequence in both mining districts. Mycorrhizal rate was close to 100% in both districts. Mycorrhizal abundance was higher in the organic forest floor layer than the mineral soil layer. In total, 25 morphotypes were recorded. Diversity differed between the districts. The mycorrhizae of Amphinema byssoides, Tuber puberulum, Pinirhiza discolor, Pinirhiza cf. bicolorata and E-type were present in both mining areas. These morphotypes are typical of nutrient-rich soils with high pH values. Compared with the undisturbed sites, vitality of mycorrhizae was very high at the test sites on spoil substrate, correlating with the high growth dynamics of mycorrhizae at recultivation sites. A relatively high carbon flow to the mycorrhizal root systems at these sites seems likely. Thus, mycorrhizal root systems are able to cope with the ameliorated top-spoil and the organic layer. The main reason for the adaptation is the large number of ectomycorrhizal fungal species available in this area where Pinus sylvestris is indigenous.

  8. Atractiellomycetes belonging to the 'rust' lineage (Pucciniomycotina) form mycorrhizae with terrestrial and epiphytic neotropical orchids.

    Science.gov (United States)

    Kottke, Ingrid; Suárez, Juan Pablo; Herrera, Paulo; Cruz, Dario; Bauer, Robert; Haug, Ingeborg; Garnica, Sigisfredo

    2010-04-22

    Distinctive groups of fungi are involved in the diverse mycorrhizal associations of land plants. All previously known mycorrhiza-forming Basidiomycota associated with trees, ericads, liverworts or orchids are hosted in Agaricomycetes, Agaricomycotina. Here we demonstrate for the first time that Atractiellomycetes, members of the 'rust' lineage (Pucciniomycotina), are mycobionts of orchids. The mycobionts of 103 terrestrial and epiphytic orchid individuals, sampled in the tropical mountain rainforest of Southern Ecuador, were identified by sequencing the whole ITS1-5.8S-ITS2 region and part of 28S rDNA. Mycorrhizae of 13 orchid individuals were investigated by transmission electron microscopy. Simple septal pores and symplechosomes in the hyphal coils of mycorrhizae from four orchid individuals indicated members of Atractiellomycetes. Molecular phylogeny of sequences from mycobionts of 32 orchid individuals out of 103 samples confirmed Atractiellomycetes and the placement in Pucciniomycotina, previously known to comprise only parasitic and saprophytic fungi. Thus, our finding reveals these fungi, frequently associated to neotropical orchids, as the most basal living basidiomycetes involved in mycorrhizal associations of land plants.

  9. A.B. Frank and mycorrhizae: the challenge to evolutionary and ecologic theory.

    Science.gov (United States)

    Trappe, James M

    2005-06-01

    A. B. Frank's observations and hypotheses about mycorrhizae in 1885 flew in the face of conventional thinking of the time. He reported that what we now term ectomycorrhizae were widespread on root systems of many woody plant species in a great diversity of habitats and soils. He hypothesized that mycorrhizae represent a pervasive mutualistic symbiosis in which fungus and host nutritionally rely on each other; that the fungus extracts nutrients from both mineral soil and humus and translocates them to the tree host; and that the tree, in turn, nourishes the fungus. Initially opposed by much of the scientific community, nearly all of Frank's major hypotheses have since been unequivocally demonstrated, although many decades were required to achieve conclusive evidence. Nonetheless, the revolution in thinking about plant and fungal evolution, ecology and physiology generated by Frank is still in the process of acceptance by much of the scientific community, 120 years and tens of thousands of scientific papers since he coined the term "mycorrhiza". The reasons for this extraordinary lag time in themselves present an intriguing research subject.

  10. [Response of arbuscular mycorrhizal fungal lipid metabolism to symbiotic signals in mycorrhiza].

    Science.gov (United States)

    Tian, Lei; Li, Yuanjing; Tian, Chunjie

    2016-01-04

    Arbuscular mycorrhizal (AM) fungi play an important role in energy flow and nutrient cycling, besides their wide distribution in the cosystem. With a long co-evolution, AM fungi and host plant have formed a symbiotic relationship, and fungal lipid metabolism may be the key point to find the symbiotic mechanism in arbusculart mycorrhiza. Here, we reviewed the most recent progress on the interaction between AM fungal lipid metabolism and symbiotic signaling networks, especially the response of AM fungal lipid metabolism to symbiotic signals. Furthermore, we discussed the response of AM fungal lipid storage and release to symbiotic or non-symbiotic status, and the correlation between fungal lipid metabolism and nutrient transfer in mycorrhiza. In addition, we explored the feedback of the lipolysis process to molecular signals during the establishment of symbiosis, and the corresponding material conversion and energy metabolism besides the crosstalk of fungal lipid metabolism and signaling networks. This review will help understand symbiotic mechanism of arbuscular mycorrhiza fungi and further application in ecosystem.

  11. Spider mites adaptively learn recognizing mycorrhiza-induced changes in host plant volatiles.

    Science.gov (United States)

    Patiño-Ruiz, J David; Schausberger, Peter

    2014-12-01

    Symbiotic root micro-organisms such as arbuscular mycorrhizal fungi commonly change morphological, physiological and biochemical traits of their host plants and may thus influence the interaction of aboveground plant parts with herbivores and their natural enemies. While quite a few studies tested the effects of mycorrhiza on life history traits, such as growth, development and reproduction, of aboveground herbivores, information on possible effects of mycorrhiza on host plant choice of herbivores via constitutive and/or induced plant volatiles is lacking. Here we assessed whether symbiosis of the mycorrhizal fungus Glomus mosseae with common bean plants Phaseolus vulgaris influences the response of the two-spotted spider mite Tetranychus urticae to volatiles of plants that were clean or infested with spider mites. Mycorrhiza-naïve and -experienced spider mites, reared on mycorrhizal or non-mycorrhizal bean plants for several days before the experiments, were subjected to Y-tube olfactometer choice tests. Experienced but not naïve spider mites distinguished between constitutive volatiles of clean non-mycorrhizal and mycorrhizal plants, preferring the latter. Neither naïve nor experienced spider mites distinguished between spider mite-induced volatiles of mycorrhizal and non-mycorrhizal plants. Learning the odor of clean mycorrhizal plants, resulting in a subsequent preference for these odors, is adaptive because mycorrhizal plants are more favorable host plants for fitness of the spider mites than are non-mycorrhizal plants.

  12. Mycorrhization between Cistus ladanifer L. and Boletus edulis Bull is enhanced by the mycorrhiza helper bacteria Pseudomonas fluorescens Migula.

    Science.gov (United States)

    Mediavilla, Olaya; Olaizola, Jaime; Santos-del-Blanco, Luis; Oria-de-Rueda, Juan Andrés; Martín-Pinto, Pablo

    2016-02-01

    Boletus edulis Bull. is one of the most economically and gastronomically valuable fungi worldwide. Sporocarp production normally occurs when symbiotically associated with a number of tree species in stands over 40 years old, but it has also been reported in 3-year-old Cistus ladanifer L. shrubs. Efforts toward the domestication of B. edulis have thus focused on successfully generating C. ladanifer seedlings associated with B. edulis under controlled conditions. Microorganisms have an important role mediating mycorrhizal symbiosis, such as some bacteria species which enhance mycorrhiza formation (mycorrhiza helper bacteria). Thus, in this study, we explored the effect that mycorrhiza helper bacteria have on the efficiency and intensity of the ectomycorrhizal symbiosis between C. ladanifer and B. edulis. The aim of this work was to optimize an in vitro protocol for the mycorrhizal synthesis of B. edulis with C. ladanifer by testing the effects of fungal culture time and coinoculation with the helper bacteria Pseudomonas fluorescens Migula. The results confirmed successful mycorrhizal synthesis between C. ladanifer and B. edulis. Coinoculation of B. edulis with P. fluorescens doubled within-plant mycorrhization levels although it did not result in an increased number of seedlings colonized with B. edulis mycorrhizae. B. edulis mycelium culture time also increased mycorrhization levels but not the presence of mycorrhizae. These findings bring us closer to controlled B. edulis sporocarp production in plantations.

  13. Diversity of arbuscular mycorrhiza in the rhizosphere of Cajeput in agroforestry system with different fertilizer management of maize

    Science.gov (United States)

    Parwi; Pudjiasmanto, B.; Purnomo, D.; Cahyani, VR

    2017-11-01

    This study investigated the diversity of arbuscular mycorrhiza in rhizosphere of cajeput with different fertilizer management of maize. This research was conducted by observation on cajeput agroforestry system in Ponorogo that have different fertilizer management of maize: conventional management (CM), universal management (UM) and alternative management (AM1, AM2, and AM3). The result showed that the highest infection of arbuscular mycorrhiza was observed in the plot of AM3, while the lowest colonization was observed in the plot of CM. Infection of arbuscular mycorrhiza in roots cajeput from five fertilizer management, ranging from 32.64% - 63.33%. In all fertilizer management, there were eight species of arbuscular mycorrhiza which five species were Glomus genus, one species was Acaulospora genus and two species were Gigaspora genus. Glomus constrictum was the dominant species in all fertilizer management. Acaulospora favoeta was found only in the plot of AM3. Spore density varies between 150-594 / 100g of soil. The highest spore density was observed in the plot of AM3, while the lowest spore density was observed in the plot of AM1. The highest diversity index value of arbuscular mycorrhiza (Species richness and Shannon-Wiener) was observed in the plot of AM3.

  14. Populasi jamur mikoriza vesikular-arbuskular pada lahan bekas galian emas yang direklamasi dengan legum tumbuh cepat dikombinasikan dengan penutup tanah dan mikroba

    Directory of Open Access Journals (Sweden)

    Suciatmih Suciatmih

    2012-02-01

    Full Text Available field work has been carried out to study the population of vesicular-arbuscular mycorrhizal (VAM fungi on degraded gold mining land that was reclamated with fast growing legume (Enterolobium sp. and Acacia mangium trees in combination with cover crops (Centrosema pubescen dan Flemingia congesta and microbe (VAM fungi, Rhizobium sp. and mixed Rhizobium sp. and phosphate solubilizing bacteria inoculation. Reclamation with fast growing legumes in combination with cover crops and microbe inoculation on the degraded land increased the population of VAM fungi. After 1.5 years, the population of the fungi on the reclamated land increased from 3.4 (control to 6.1–80.5 spore/g soil. The highest spore population resulted by combination between Acacia mangium, C. pubescen, and VAM fungi (V2I1C1 plot followed by combination between Acacia mangium without cover crop, and VAM fungi inoculation (V2I1C0 plot and combination between Enterolobium sp. without cover crop and mixed Rhizobium and phosphate solubilizing bacteria inoculation (V1I3Co plot were 80.5, 56.0 and 51.8 respectively.

  15. Relació de les velocitats finals assolides entre la Course Navette de 20 metres i el test de VAM-EVAL. Una proposta per predir la velocitat aeròbica màxima

    OpenAIRE

    García, Gastón; Secchi, Jeremías

    2013-01-01

    Introducció: L’objectiu d’aquest estudi fou proposar una taula de correcció per predir la velocitat aeròbica màxima (VAM) a partir del test de la Course Navette de 20 m (CN-20 m) en ambdós sexes. Material i mètodes: Setanta-set subjectes (46 homes i 31 dones), estudiants d’educació física, participaren voluntàriament a l’estudi. Foren avaluats en 3 ocasions. Primer es féu l’avaluació antropomètrica en el laboratori. En les 2 oportunitats següents foren avaluats aleatòriament en el camp am...

  16. Research on: A. Reclamation of borrow pits and denuded lands; B. Biochemical aspects of mycorrhizae of forest trees

    Energy Technology Data Exchange (ETDEWEB)

    Marx, D.H. (comp.)

    1990-12-01

    This report furnishes a list of compiled and ongoing studies and a list of publications which resulted from the research accomplished by Institute scientists and other collaborators. The research accomplished can be placed in four categories: I. Research on borrow pit rehabilitation with 12 publications; II. Research on artificial regeneration of southern pines with 34 publications; III. Research on artificial regeneration of eastern hardwoods with 16 publications; and IV. Cooperative research with the University of Georgia on biochemical aspects of mycorrhizae with 5 publications. Major accomplishments of this research are: 1. Procedures to successfully reclaim borrow pits with sludge, subsoiling and seedlings with specific mycorrhizae. 2. Protocols to successfully artificially regenerate southern pines (particularly ling leaf pine) and certain eastern hardwoods. 3. Basic understanding of the biochemistry of mycorrhizae and the discovery of a new pathway for sucrose utilization in plants. 67 refs.

  17. Uptake and speciation of selenium in garlic cultivated in soil amended with symbiotic fungi (mycorrhiza) and selenate

    DEFF Research Database (Denmark)

    Larsen, Erik Huusfeldt; Lobinski, R.; Burger-Meyer, K.

    2006-01-01

    The scope of the work was to investigate the influence of selenate fertilisation and the addition of symbiotic fungi (mycorrhiza) to soil on selenium and selenium species concentrations in garlic. The selenium species were extracted from garlic cultivated in experimental plots by proteolytic...... in garlic. The selenium content in garlic, which was analysed by ICP-MS, showed that addition of mycorrhiza to the natural soil increased the selenium uptake by garlic tenfold to 15 mu g g(-1) (dry mass). Fertilisation with selenate and addition of mycorrhiza strongly increased the selenium content...... in garlic to around one part per thousand. The parallel analysis of the sample extracts by cation exchange and reversed-phase HPLC with ICP-MS detection showed that gamma-glutamyl-Se-methyl-selenocysteine amounted to 2/3, whereas methylselenocysteine, selenomethionine and selenate each amounted to a few...

  18. Oxygen evolution from tomato (C3) plants with and without mycorrhiza: Open photoacoustic cell measurement and statistical analysis

    Science.gov (United States)

    Sanchez-Rocha, S.; Vargas-Luna, M.; Gutiérrez-Juárez, G.; Huerta Franco, R.; Madueño, L.; Olalde-Portugal, V.

    2005-06-01

    Mycorrhiza, a common association between root plants and mycorrhizic fungus provides some benefits to the plant, improving its nutrient uptake and increasing the drought resistance as well as the photosynthetic rate. Open photoacoustic (OPC) cell technique was used here to study oxygen evolution from C3 plants (tomato) with and with mycorrhizic fungus (Glomus Fasciculatum) under the lighting conditions similar to those characteristic for the mid-day sunlight. The OPC was found capable of discriminating between the two contributions to photoacoustic signal. The experimental evidence was collected for statistically significant differences between photobaric signals from plants with and without mycorrhiza.

  19. Influence of soil chemical properties on relative abundance of arbuscular mycorrhiza in forested soils in Malaysia

    OpenAIRE

    ONG, Kian Huat; CHUBO, John Keen; KING, Jie Hung; LEE, Chia Shing; SU, Dennis Shan An; SIPEN, Philip

    2012-01-01

    The effect of soil chemical properties on the diversity and colonization of arbuscular mycorrhiza (AM) varies among ecosystems. This study was conducted to assess and compare the abundance of AM in a rehabilitated forest and a logged-over forest soil using the most probable number and spore number methods. Glomus (71.7%-82.1%) and Acaulospora (17.4%-19.5%) were found to be abundant in both sites, while Gigaspora was found only in the logged-over forest. The abundance of AM in the rehabilitate...

  20. Early phosphorus nutrition, mycorrhizae development, dry matter partitioning and yield of maize

    DEFF Research Database (Denmark)

    Gavito, M.E.; Miller, M.H.

    1998-01-01

    was used with previous crop (Zea mays L.-maize and Brassica napus L.-canola), tillage practices (no-tillage or conventional tillage) and P fertilization (5 levels) as factors chosen to modify mycorrhizae development at early developmental stages of maize. Previous cropping with canola resulted in decreased...... to a mycorrhizal mycelium network (no-tillage treatments). Maize yield and harvest index were lower after cropping With canola. The yield for conventional tillage was higher than that for no-tillage but the harvest index was lower. The hypothesis was supported at early stages of maize growth by the effect...

  1. [Study on application of arbuscular-mycorrhizas in growing seedings of Aloe vera].

    Science.gov (United States)

    Gong, Mingqin; Wang, Fengzhen; Chen, Yu

    2002-01-01

    Tissue culture seedlings of Aloe vera L. inoculated with 7 AMF(arbuscular mycorrhiza fungi) in a greenhouse in Guangzhou showed that the percentage of infection was 99.67%-100%, the index of infected was 73.3%-86.67%. After being inoculated 13 months, the seedling high raised 19.88%-51.91%, the leaves length raised 13.13%-150.96%. After being inoculated 15 months, the leaves juice of Aloe vera raised 60.87%-233.8% and the dried of leaves juice raised 217%-724%.

  2. Arbuscular mycorrhiza of plants spontaneously colonizing the soda heap in Jaworzno (southern Poland

    Directory of Open Access Journals (Sweden)

    Ewa Gucwa-Przepióra

    2011-01-01

    Full Text Available The results of studies of the mycorrhizal status of plant species spontaneously established on the soda heap located in Jaworzno (Upper Silesia, Poland are presented. Additionally, the species of arbuscular fungi of the phylum Glomeromycota extracted from field-collected rhizosphere substrate samples of the heap are showed. Arbuscular mycorrhizae were described in 17 plant species. Five Glomus spp. were recognized in the spore populations of arbuscular fungi isolated. The investigation presented in this paper for the first time revealed Centaurea stoebe and Trifolium montanum to be hosts of arbuscular fungi.

  3. Uptake and specification of selenium in garlic cultivated in soil amended with symbiotic fungi (mycorrhiza) and selenate

    NARCIS (Netherlands)

    Larsen, E.H.; Lobinski, R.; Burger-Meijer, K.; Hansen, M.; Ruzik, R.; Mazurowska, L.; Rasmussen, P.H.; Sloth, J.J.; Scholten, O.E.; Kik, C.

    2006-01-01

    The scope of the work was to investigate the influence of selenate fertilisation and the addition of symbiotic fungi (mycorrhiza) to soil on selenium and selenium species concentrations in garlic. The selenium species were extracted from garlic cultivated in experimental plots by proteolytic

  4. No significant transfer of N and P from Pueraria Phaseoloides to Hevea Brasiliensis via Hyphal links of Arbuscular Mycorrhiza

    DEFF Research Database (Denmark)

    Ikram, A.; Jensen, E.S.; Jakobsen, I.

    1994-01-01

    and averaged 0.05 and 0.03% for mycorrhizal and non-mycorrhizal H. brasiliensis. The estimated transfer of N and P from P. phaseoloides to H. brasiliensis was not affected by mycorrhizas despite the high degree of root colonization in both species. The percentage of total legume N transferred to H...

  5. Early changes in arbuscular mycorrhiza development in sugarcane under two harvest management systems.

    Science.gov (United States)

    de Azevedo, Lucas Carvalho Basilio; Stürmer, Sidney Luiz; Lambais, Marcio Rodrigues

    2014-01-01

    Sugarcane (Saccharum spp.) is grown on over 8 million ha in Brazil and is used to produce ethanol and sugar. Some sugarcane fields are burned to facilitate harvesting, which can affect the soil microbial community. However, whether sugarcane pre-harvest burning affects the community of arbuscular mycorrhizal fungi (AMF) and symbioses development is not known. In this study, we investigated the early impacts of harvest management on AMF spore communities and root colonization in three sugarcane varieties, under two harvest management systems (no-burning and pre-harvest burning). Soil and root samples were collected in the field after the first harvest of sugarcane varieties SP813250, SP801842, and RB72454, and AMF species were identified based on spore morphology. Diversity indices were determined based on spore populations and root colonization determined as an indicator of symbioses development. Based on the diversity indices, spore number and species occurrence in soil, no significant differences were observed among the AMF communities, regardless of harvest management type, sugarcane variety or interactions between harvest management type and sugarcane variety. However, mycorrhiza development was stimulated in sugarcane under the no-burning management system. Our data suggest that the sugarcane harvest management system may cause early changes in arbuscular mycorrhiza development.

  6. Early changes in arbuscular mycorrhiza development in sugarcane under two harvest management systems

    Directory of Open Access Journals (Sweden)

    Lucas Carvalho Basilio de Azevedo

    2014-09-01

    Full Text Available Sugarcane (Saccharum spp. is grown on over 8 million ha in Brazil and is used to produce ethanol and sugar. Some sugarcane fields are burned to facilitate harvesting, which can affect the soil microbial community. However, whether sugarcane pre-harvest burning affects the community of arbuscular mycorrhizal fungi (AMF and symbioses development is not known. In this study, we investigated the early impacts of harvest management on AMF spore communities and root colonization in three sugarcane varieties, under two harvest management systems (no-burning and pre-harvest burning. Soil and root samples were collected in the field after the first harvest of sugarcane varieties SP813250, SP801842, and RB72454, and AMF species were identified based on spore morphology. Diversity indices were determined based on spore populations and root colonization determined as an indicator of symbioses development. Based on the diversity indices, spore number and species occurrence in soil, no significant differences were observed among the AMF communities, regardless of harvest management type, sugarcane variety or interactions between harvest management type and sugarcane variety. However, mycorrhiza development was stimulated in sugarcane under the no-burning management system. Our data suggest that the sugarcane harvest management system may cause early changes in arbuscular mycorrhiza development.

  7. The role of pH in Tuber aestivum syn. uncinatum mycorrhiza development within commercial orchards

    Directory of Open Access Journals (Sweden)

    Paul W. Thomas

    2013-12-01

    Full Text Available The accepted advice when establishing a plantation of Tuber aestivum syn. uncinatum is that young inoculated trees should be planted on calcareous soils with a naturally high pH level. When a site is employed that has a naturally low pH level, lime is often applied to raise the pH to a considered ideal level of c.7.5. However, this may not be the correct approach. Here we present data from 33 data points taken from commercial truffle orchards in England, UK. Soil pH is correlated to Tuber aestivum syn. uncinatum mycorrhiza survivorship and development. The optimal observed pH was 7.51 but the actual optimal pH for cultivation may be higher. Sub optimal pH levels lead to a reduction of Tuber aestivum syn. uncinatum mycorrhiza. This reduction is not permanent and mycorrhization levels may be improved within a 12 month period by amending the soil pH. The importance of understanding the interaction of pH with other variables and the results in relation truffle cultivation are discussed.

  8. Changes in Nutrient Content of Root and Grain of Wheat Cultivars Inoculated by Azospirillum and Mycorrhiza

    Directory of Open Access Journals (Sweden)

    M. Jiriaie

    2016-02-01

    Full Text Available Introduction: Providing the nutritional requirements of agricultural crops by non-chemical resources is a new approach in the organic farming that has attracted the attention of both the researchers and the consumers in recent years. Therefore, it is highly important to find new fertilizer resources that are both economically able to provide the nutritional needs of the crop plants and have no adverse effects on the consumers and the environment. Materials and Methods: With this approach, an experiment was conducted in the research station of Shahid Chamran University of Ahvaz, Iran in 2012-13. The experimental design was factorial based on randomized complete blocks design with three replications. The treatments including Mycorrhizal fungi in three levels (i.e. no use of strain; use of Glomus intraradices strain; and use of Glomus mosseae strain, bacteria Azospirillum lipoferum in two-levels (i.e. non-inoculated and inoculated and wheat cultivars in three levels (i.e. Chamran; Dena; and Behrang. The measured parameters include the concentration of macronutrients (i.e. nitrogen, phosphorus and potassium and some micronutrients (i.e. zinc, iron and manganese in two part seed and the root of wheat. Results and Discussion: Surveying the elements content in the root and the grain indicated a significant and positive effect of the use the Azospirillum and Mycorrhiza to improve the concentration of the elements in wheat cultivars. However, the simultaneous use of these microorganisms led to an increase of the effects of their application on their assessed traits.Finally the highest concentration of N (2.21 present, P (0.50 present and Fe (33.88 mg.kg-1 were observed in the grain; the highest concentration of K (0.93 present and 0.54 present and Mn (43.11 and 23.63 mg.kg-1 were observed in the grain and root, respectively. Moreover, the highest concentration of Zn in the root (19.70 mg.kg-1 was obtained from inoculation of C.V Dena seeds with

  9. Plant growth and arbuscular mycorrhizae development in oil sands processing by-products.

    Science.gov (United States)

    Boldt-Burisch, Katja; Naeth, M Anne; Schneider, Uwe; Schneider, Beate; Hüttl, Reinhard F

    2017-11-22

    Soil pollutants such as hydrocarbons can induce toxic effects in plants and associated arbuscular mycorrhizal fungi (AMF). This study was conducted to evaluate if the legume Lotus corniculatus and the grass Elymus trachycaulus and arbuscular mycorrhizal fungi could grow in two oil sands processing by-products after bitumen extraction from the oil sands in northern Alberta, Canada. Substrate treatments were coarse tailings sand (CTS), a mix of dry mature fine tailings (MFT) with CTS (1:1) and Pleistocene sandy soil (hydrocarbon free); microbial treatments were without AMF, with AMF and AMF plus soil bacteria isolated from oil sands reclamation sites. Plant biomass, root morphology, leaf water content, shoot tissue phosphorus content and mycorrhizal colonization were evaluated. Both plant species had reduced growth in CTS and tailings mix relative to sandy soil. AMF frequency and intensity in roots of E. trachycaulus was not influenced by soil hydrocarbons; however, it decreased significantly over time in roots of L. corniculatus without bacteria in CTS. Mycorrhizal inoculation alone did not significantly improve plant growth in CTS and tailings mix; however, inoculation with mycorrhizae plus bacteria led to a significantly positive response of both plant species in CTS. Thus, combined inoculation with selected mycorrhizae and bacteria led to synergistic effects. Such combinations may be used in future to improve plant growth in reclamation of CTS and tailings mix. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. The role of arbuscular mycorrhizae in primary succession: differences and similarities across habitats

    Directory of Open Access Journals (Sweden)

    Z. Kikvidze

    2010-12-01

    Full Text Available Primary succession is an ecological process of fundamental importance referring to the development of vegetation on areas not previously occupied by a plant community. The bulk of knowledge on primary succession comes from areas affected by relatively recent volcanic eruptions, and highlights the importance of symbiosis between host plants and fungi for the initial stages of succession. Arbuscular mycorrhizas (AM are of particular interest as they are often present from the very beginning of primary succession and because they show different relationships with pioneer and late-successional species, which suggests they may be involved in important, yet unknown, ecological mechanisms of succession. We review existing knowledge based on case studies from the volcanic desert of Mount Fuji, Japan, where primary succession was examined intensively and which represents one of the best-known cases on the role of AM in primary succession. We also assess the potential of sand dunes and semi-arid, erosion-prone systems for addressing the role of mycorrhizas in primary succession. Analyzing primary succession under different ecological systems is critical to understand the role of AM in this basic process. While volcanoes and glaciers are restricted to particular mountainous areas, naturally eroded areas and sand dunes are more common and easily accessible, making them attractive models to study primary succession.

  11. Remote Sensing of Mycorrhizae? Detection of Mycorrhizal Association from Canopy Spectral Properties.

    Science.gov (United States)

    Fisher, J. B.; Sweeney, S.; Brzostek, E. R.; Evans, T. P.; Bourg, N. A.; Phillips, R.

    2014-12-01

    Nearly all tree species form symbiotic relationships with one of two types of mycorrzhae—arbuscular mycorrhizae (AM) and ectomycorrhizal (ECM) fungi. AM- and ECM-dominated forests often have distinct nutrient economies, and there is strong interest in mapping or detecting mycorrhizae over large areas. We explored remotely sensed tree canopy spectral properties to "detect" underlying mycorrhizal association across a gradient of AM- and ECM-dominated forest plots. We used a combination of principal components analysis and statistical mining of reflectance and band differencing across moderate/high-resolution Landsat data in conjunction with phenological signals from stitched seasonal time series and topographic features. This approach was trained and validated against measurements of tree species and mycorrhizal association across more than 60,000 trees throughout the central and eastern US. Using this approach, we were able to predict 81% of the variation in mycorrhizal association (p<0.001). Differences in phenological characteristics between AM- and ECM-associated trees drove the relatively high prediction skill.

  12. Ethylene-dependent/ethylene-independent ABA regulation of tomato plants colonized by arbuscular mycorrhiza fungi.

    Science.gov (United States)

    Martín-Rodríguez, José Ángel; León-Morcillo, Rafael; Vierheilig, Horst; Ocampo, Juan Antonio; Ludwig-Müller, Jutta; García-Garrido, José Manuel

    2011-04-01

    We investigated the relationship between ABA and ethylene regulating the formation of the arbuscular mycorrhiza (AM) symbiosis in tomato (Solanum lycopersicum) plants and tried to define the specific roles played by each of these phytohormones in the mycorrhization process. We analysed the impact of ABA biosynthesis inhibition on mycorrhization by Glomus intraradices in transgenic tomato plants with an altered ethylene pathway. We also studied the effects on mycorrhization in sitiens plants treated with the aminoethoxyvinyl glycine hydrochloride (AVG) ethylene biosynthesis inhibitor and supplemented with ABA. In addition, the expression of plant and fungal genes involved in the mycorrhization process was studied. ABA biosynthesis inhibition qualitatively altered the parameters of mycorrhization in accordance with the plant's ethylene perception and ethylene biosynthesis abilities. Inhibition of ABA biosynthesis in wild-type plants negatively affected all the mycorrhization parameters studied, while tomato mutants impaired in ethylene synthesis only showed a reduced arbuscular abundance in mycorrhizal roots. Inhibition of ethylene synthesis in ABA-deficient sitiens plants increased the intensity of mycorrhiza development, while ABA application rescued arbuscule abundance in the root's mycorrhizal zones. The results of our study show an antagonistic interaction between ABA and ethylene, and different roles of each of the two hormones during AM formation. This suggests that a dual ethylene-dependent/ethylene-independent mechanism is involved in ABA regulation of AM formation. © 2011 The Authors. New Phytologist © 2011 New Phytologist Trust.

  13. Effects of genetic modifications to flax (Linum usitatissimum) on arbuscular mycorrhiza and plant performance.

    Science.gov (United States)

    Wróbel-Kwiatkowska, Magdalena; Turnau, Katarzyna; Góralska, Katarzyna; Anielska, Teresa; Szopa, Jan

    2012-10-01

    Although arbuscular mycorrhizal fungi (AMF) are known for their positive effect on flax growth, the impact of genetic manipulation in this crop on arbuscular mycorrhiza and plant performance was assessed for the first time. Five types of transgenic flax that were generated to improve fiber quality and resistance to pathogens, through increased levels of either phenylpropanoids (W92.40), glycosyltransferase (GT4, GT5), or PR2 beta-1,3-glucanase (B14) or produce polyhydroxybutyrate (M50), were used. Introduced genetic modifications did not change the degree of mycorrhizal colonization as compared to parent cultivars Linola and Nike. Arbuscules were well developed in each tested transgenic type (except M50). In two lines (W92.40 and B14), a higher abundance of arbuscules was observed when compared to control, untransformed flax plants. However, in some cases (W92.40, GT4, GT5, and B14 Md), the mycorrhizal dependency for biomass production of transgenic plants was slightly lower when compared to the original cultivars. No significant influence of mycorrhiza on the photosynthetic activity of transformed lines was found, but in most cases P concentration in mycorrhizal plants remained higher than in nonmycorrhizal ones. The transformed flax lines meet the demands for better quality of fiber and higher resistance to pathogens, without significantly influencing the interaction with AMF.

  14. Diverse tulasnelloid fungi form mycorrhizas with epiphytic orchids in an Andean cloud forest.

    Science.gov (United States)

    Suárez, Juan Pablo; Weiss, Michael; Abele, Andrea; Garnica, Sigisfredo; Oberwinkler, Franz; Kottke, Ingrid

    2006-11-01

    The mycorrhizal state of epiphytic orchids has been controversially discussed, and the state and mycobionts of the pleurothallid orchids, occurring abundantly and with a high number of species on stems of trees in the Andean cloud forest, were unknown. Root samples of 77 adult individuals of the epiphytic orchids Stelis hallii, S. superbiens, S. concinna and Pleurothallis lilijae were collected in a tropical mountain rainforest of southern Ecuador. Ultrastructural evidence of symbiotic interaction was combined with molecular sequencing of fungi directly from the mycorrhizas and isolation of mycobionts. Ultrastructural analyses displayed vital orchid mycorrhizas formed by fungi with an imperforate parenthesome and cell wall slime bodies typical for the genus Tulasnella. Three different Tulasnella isolates were obtained in pure culture. Phylogenetic analysis of nuclear rDNA sequences from coding regions of the ribosomal large subunit (nucLSU) and the 5.8S subunit, including parts of the internal transcribed spacers, obtained directly from the roots and from the fungal isolates, yielded seven distinct Tulasnella clades. Tulasnella mycobionts in Stelis concinna were restricted to two Tulasnella sequence types while the other orchids were associated with up to six Tulasnella sequence types. All Tulasnella sequences are new to science and distinct from known sequences of mycobionts of terrestrial orchids. The results indicate that tulasnelloid fungi, adapted to the conditions on tree stems, might be important for orchid growth and maintenance in the Andean cloud forest.

  15. Giving and receiving: measuring the carbon cost of mycorrhizas in the green orchid, Goodyera repens.

    Science.gov (United States)

    Cameron, Duncan D; Johnson, Irene; Read, David J; Leake, Jonathan R

    2008-01-01

    Direct measurement of the carbon (C) 'cost' of mycorrhizas is problematic. Although estimates have been made for arbuscular and ectomycorrhizal symbioses, these are based on incomplete budgets or indirect measurements. Furthermore, the conventional model of unidirectional plant-to-fungus C flux is too simplistic. Net fungus-to-plant C transfer supports seedling establishment in c. 10% of plant species, including most orchids, and bidirectional C flows occur in ectomycorrhiza utilizing soil amino acids. Here, the C cost of mycorrhizas to the green orchid Goodyera repens was determined by measurement of simultaneous bidirectional fluxes of 14C labelled sources using a monoxenic system with the fungus Ceratobasidium cornigerum. Transfer of C from fungus to plant ('up-flow') occurs in the photosynthesizing orchid G. repens (max. 0.06 microg) whereas over five times more current assimilate (min. 0.355 microg) is simultaneously allocated in the reverse direction to the mycorrhizal fungus ('down-flow') after 8 d. Carbon is transferred rapidly, being detected in plant-fungal respiration within 31 h of labelling. This study provides the most complete C budget for an orchid-mycorrhizal symbiosis, and clearly shows net plant-to-fungus C flux. The rapidity of bidirectional C flux is indicative of dynamic transfer at an interfacial apoplast as opposed to reliance on digestion of fungal pelotons.

  16. The influence of arbuscular mycorrhizae on root precision nutrient foraging of two pioneer plant species during early reclamation

    Science.gov (United States)

    Boldt-Burisch, Katja; Naeth, M. Anne

    2017-04-01

    On many post mining sites in the Lusatian Mining District (East Germany) soil heterogeneity consists of sandy soil with embedded clay-silt fragments. Those clays silt fragments might act as nutrient hotspots. Arbuscular mycorrhizal fungi in an infertile ecosystem could enhance a plant's ability to selectively forage for those nutrients and thus to improve plants nutrient supply. In our study we investigated whether silt-clay fragments within a sandy soil matrix induced preferential root growth of Lotus corniculatus and Calamagrostis epigeios, whether arbuscular mycorrhizae influenced root foraging patterns, and to what extent selective rooting in clay silt fragments influenced plant growth were addressed in this research. Soil types were sterile and non-sterile sandy soil and clay-silt fragments. Treatments were with and without arbuscular mycorrhizae, with and without soil solution, and soil solution and mycorrhizal inoculum combined. Root biomass, root density and intraradical fungal alkaline phosphatase activity and frequency were determined in fragments relative to sandy soil. Furthermore, temporal relationship of number of roots in fragments and plant height was assessed. Lotus corniculatus showed strong selective rooting into fragments especially with those plants treated with commercial cultivated arbuscular mycorrhizae; Calamagrostis epigeios did not. Without arbuscular mycorrhizae, L. corniculatus growth was significantly reduced and selective rooting did not occur. Selective rooting induced significant growth spurts of L. corniculatus. Roots in fragments had higher fungal alkaline phosphatase activity suggesting that mycorrhizal efficiency and related plants phosphorus supply is enhanced in roots in fragments. The application of cultivated arbuscular mycorrhizal fungi significantly and quickly influenced root foraging patterns, especially those of L. corniculatus, suggesting mycorrhizae may also enhance the ability of other plants to selectively forage

  17. Interaction between C 4 barnyard grass and C 3 upland rice under elevated CO 2: Impact of mycorrhizae

    Science.gov (United States)

    Tang, Jianjun; Xu, Liming; Chen, Xin; Hu, Shuijin

    2009-03-01

    Atmospheric CO 2 enrichment may impact arbuscular mycorrhizae (AM) development and function, which could have subsequent effects on host plant species interactions by differentially affecting plant nutrient acquisition. However, direct evidence illustrating this scenario is limited. We examined how elevated CO 2 affects plant growth and whether mycorrhizae mediate interactions between C 4 barnyard grass ( Echinochloa crusgalli (L.) Beauv.) and C 3 upland rice ( Oryza sativa L.) in a low nutrient soil. The monocultures and combinations with or without mycorrhizal inoculation were grown at ambient (400 ± 20 μmol mol -1) and elevated CO 2 (700 ± 20 μmol mol -1) levels. The 15N isotope tracer was introduced to quantify the mycorrhizally mediated N acquisition of plants. Elevated CO 2 stimulated the growth of C 3 upland rice but not that of C 4 barnyard grass under monoculture. Elevated CO 2 also increased mycorrhizal colonization of C 4 barnyard grass but did not affect mycorrhizal colonization of C 3 upland rice. Mycorrhizal inoculation increased the shoot biomass ratio of C 4 barnyard grass to C 3 upland rice under both CO 2 concentrations but had a greater impact under the elevated than ambient CO 2 level. Mycorrhizae decreased relative interaction index (RII) of C 3 plants under both ambient and elevated CO 2, but mycorrhizae increased RII of C 4 plants only under elevated CO 2. Elevated CO 2 and mycorrhizal inoculation enhanced 15N and total N and P uptake of C 4 barnyard grass in mixture but had no effects on N and P acquisition of C 3 upland rice, thus altering the distribution of N and P between the species in mixture. These results implied that CO 2 stimulation of mycorrhizae and their nutrient acquisition may impact competitive interaction of C 4 barnyard grass and C 3 upland rice under future CO 2 scenarios.

  18. Isolation and phylogenetic relationship of orchid-mycorrhiza from Spathoglottis plicata of Papua using mitochondrial ribosomal large subunit (mt-Ls) DNA

    National Research Council Canada - National Science Library

    SUPENI SUFAATI; VERENA AGUSTINI; SUHARNO

    2012-01-01

    Sufaati S, Agustini V, Suharno. 2012. Isolation and phylogenetic relationship of orchid-mycorrhiza from Spathoglottis plicata of Papua using mitochondrial ribosomal large subunit (mt-Ls) DNA. Biodiversitas 13: 59-64...

  19. Roles of Arbuscular Mycorrhizas in Plant Phosphorus Nutrition: Interactions between Pathways of Phosphorus Uptake in Arbuscular Mycorrhizal Roots Have Important Implications for Understanding and Manipulating Plant Phosphorus Acquisition

    DEFF Research Database (Denmark)

    Smith, S.E.; Jakobsen, Iver; Grønlund, Mette

    2011-01-01

    In this Update, we review new findings about the roles of the arbuscular mycorrhizas (mycorrhiza = fungus plus root) in plant growth and phosphorus (P) nutrition. We focus particularly on the function of arbuscular mycorrhizal (AM) symbioses with different outcomes for plant growth (from positive...... and the regulation of P acquisition to the roles of AM fungi in determining the composition of natural plant assemblages in ecological settings and their changes with time....

  20. Plant Protection Research Institute

    Directory of Open Access Journals (Sweden)

    N. Allsopp

    1993-12-01

    Full Text Available A survey of the mycorrhizal status of plants growing in the Cape Floristic Region of South Africa was undertaken to assess the range of mycorrhizal types and their dominance in species characteristic of this region. Records were obtained by ex­amining the root systems of plants growing in three Cape lowland vegetation types, viz. West Coast Strandveld, West Coast Renosterveld and Sand Plain Lowland Fynbos for mycorrhizas, as well as by collating literature records of mycorrhizas on plants growing in the region. The mycorrhizal status of 332 species is listed, of which 251 species are new records. Members of all the important families in this region have been examined. Mycorrhizal status appears to be associated mainly with taxonomic position of the species. Extrapolating from these results, we conclude that 62% of the flora of the Cape Floristic Region form vesicular-arbuscular mycorrhizas, 23% have no mycorrhizas, 8% are ericoid mycorrhizal, 2% form orchid mycorrhizas, whereas the mycorrhizal status of 4% of the flora is unknown. There were no indigenous ectomycor- rhizal species. The proportion of non-mycorrhizal species is high compared to other ecosystems. In particular, the lack of mycorrhizas in several important perennial families in the Cape Floristic Region is unusual. The diversity of nutrient acquir­ing adaptations, including the range of mycorrhizas and cluster roots in some non-mycorrhizal families, may promote co­existence of plants in this species-rich region.

  1. Sheep manure vermicompost supplemented with a native diazotrophic bacteria and mycorrhizas for maize cultivation.

    Science.gov (United States)

    Gutiérrez-Miceli, F A; Moguel-Zamudio, B; Abud-Archila, M; Gutiérrez-Oliva, V F; Dendooven, L

    2008-10-01

    An orthogonal experimental design L9 (3(4)) with 10 repetitions was used to investigate the effect of Glomus claroideum (0, 1 or 2g(-1) plant), G. fasciculatum (0, 1 or 2g plant(-1)), native diazotrophic bacteria (0, 10(3) and 10(5) UFC ml(-1)) and sheep manure vermicompost (0%, 5% and 10% v/v) on maize plant growth, N and P in leaves and mycorrhization percent. Vermicompost explained most of the variation found for leaf number, wet weight, stem height, and diameter. Both mycorrhizas increased the plant wet weight but G. fasciculatum the most. Mycorrhization increased the P content, but not the N content. Mycorrhizal colonization increased when diazotrophic bacteria and vermicompost were added. It was found that weight of maize plants cultivated in peat moss amended with vermicompost increased when supplemented with G. fasciculatum and diazotrophic bacteria.

  2. Arbuscular mycorrhizas contribute to phyto stabilization of uranium in uranium mining tailings

    DEFF Research Database (Denmark)

    Chen, Bao-Dong; Roos, Per; Zhu, Yong-Guan

    2008-01-01

    extensively colonized by G. intraradices whereas ryegrass were more sparsely colonized. Plant growth was not improved by mycorrhizas, which, however, improved P nutrition of medic plants. Medic plants contained higher U concentrations and showed higher specific U uptake efficiency compared to ryegrass....... In the presence of U tailing, most U had been retained in plant roots, and this distribution pattern was further enhanced by mycorrhizal colonization. The results suggest a role for AM fungi in phytostabilization of U tailings. (c) 2007 Elsevier Ltd. All rights reserved.......Uranium (U) tailings pose environmental risks and call for proper remediation. In this paper medic and ryegrass plants were used as host plants to examine whether inoculation with an AM fungus, Glomus intraradices, would help phytostabilization of U tailings. The need of amending...

  3. Predicting plant responses to mycorrhizae: integrating evolutionary history and plant traits.

    Science.gov (United States)

    Reinhart, Kurt O; Wilson, Gail W T; Rinella, Matthew J

    2012-07-01

    We assessed whether (1) arbuscular mycorrhizal colonization of roots (RC) and/or plant responses to arbuscular mycorrhizae (MR) vary with plant phylogeny and (2) MR and RC can be more accurately predicted with a phylogenetic predictor relative to a null model and models with plant trait and taxonomic predictors. In a previous study, MR and RC of 95 grassland species were measured. We constructed a phylogeny for these species and found it explained variation in MR and RC. Next, we used multiple regressions to identify the models that most accurately predicted plant MR. Models including either phylogenetic or phenotypic and taxonomic information similarly improved our ability to predict MR relative to a null model. Our study illustrates the complex evolutionary associations among species and constraints of using phylogenetic information, relative to plant traits, to predict how a plant species will interact with AMF. Published 2012. This article is a US Government work and is in the public domain in the USA.

  4. Nitrogen and carbon/nitrogen dynamics in arbuscular mycorrhiza: the great unknown.

    Science.gov (United States)

    Corrêa, A; Cruz, C; Ferrol, N

    2015-10-01

    Many studies have established that arbuscular mycorrhizal fungi transfer N to the host plant. However, the role and importance of arbuscular mycorrhiza (AM) in plant N nutrition is still uncertain, as are the C/N interactions within the symbiosis. Published reports provide differing, and often contradictory, results that are difficult to combine in a coherent framework. This review explores questions such as: What makes the difference between a positive and a negative effect of AM on plant N nutrition? Is the mycorrhizal N response (MNR) correlated to the mycorrhizal growth response (MGR), and how or under which conditions? Is the MNR effect on plant growth C mediated? Is plant C investment on fungal growth related to N needs or N benefit? How is the N for C trade between symbionts regulated? The patternless nature of current knowledge is made evident, and possible reasons for this are discussed.

  5. Mycorrhiza-induced resistance: more than the sum of its parts?

    Science.gov (United States)

    Cameron, Duncan D.; Neal, Andrew L.; van Wees, Saskia C.M.; Ton, Jurriaan

    2014-01-01

    Plants can develop an enhanced defensive capacity in response to infection by arbuscular mycorrhizal fungi (AMF). This ‘mycorrhiza-induced resistance’ (MIR) provides systemic protection against a wide range of attackers and shares characteristics with systemic acquired resistance (SAR) after pathogen infection and induced systemic resistance (ISR) following root colonisation by non-pathogenic rhizobacteria. It is commonly assumed that fungal stimulation of the plant immune system is solely responsible for MIR. In this opinion article, we present a novel model of MIR that integrates different aspects of the induced resistance phenomenon. We propose that MIR is a cumulative effect of direct plant responses to mycorrhizal infection and indirect immune responses to ISR-eliciting rhizobacteria in the mycorrhizosphere. PMID:23871659

  6. The relationship between thiamine and two symbioses: Root nodule symbiosis and arbuscular mycorrhiza.

    Science.gov (United States)

    Nagae, Miwa; Parniske, Martin; Kawaguchi, Masayoshi; Takeda, Naoya

    2016-12-01

    Lotus japonicus THIC is expressed in all organs, and the encoded protein catalyzes thiamine biosynthesis. Loss of function produces chlorosis, a typical thiamine-deficiency phenotype, and mortality. To investigate thiamine's role in symbiosis, we focused on THI1, a thiamine-biosynthesis gene expressed in roots, nodules, and seeds. The thi1 mutant had green leaves, but formed small nodules and immature seeds. These phenotypes were rescued by THI1 complementation and by exogenous thiamine. Thus, THI1 is required for nodule enlargement and seed maturation. On the other hand, colonization by arbuscular mycorrhiza (AM) fungus Rhizophagus irregularis was not affected in the thi1 mutant or by exogenous thiamine. However, spores of R. irregularis stored more thiamine than the source (host plants), despite lacking thiamine biosynthesis genes. Therefore, disturbance of the thiamine supply would affect progeny phenotypes such as spore formation and hyphal growth. Further investigation will be required to elucidate thiamine's effect on AM.

  7. Development of root-symbiosis systems for testing environmental chemicals in their effects in soils; Entwicklung eines Wurzelsymbiosesystems zum Testen von Umweltchemikalien auf ihre Wirkung in Boeden

    Energy Technology Data Exchange (ETDEWEB)

    Werner, D. [Marburg Univ. (Germany). Abt. Angewandte Botanik; Wetzel, A. [Marburg Univ. (Germany). Abt. Angewandte Botanik; Goerge, E. [Marburg Univ. (Germany). Abt. Angewandte Botanik; Brandt, S. [Marburg Univ. (Germany). Abt. Angewandte Botanik; Klante, G. [Marburg Univ. (Germany). Abt. Angewandte Botanik

    1992-03-31

    Root symbiosis of legumes with symbiotic bacteria of the genus Rhizobium and with symbiotic fungi (vesicular-arbuscular mycorrhiza) have been established as sensitive bioindicators for soil environmental chemicals. For different plant species also different transfer rates for those substances have been found. Towards heavy metals (cadmium, lead, arsenite) the symbioses react very differentiated. As environmental chemicals chinoline, fluoranthene, phenanthrene und anthracene have been studied. (orig.) [Deutsch] Die Wurzelsymbiosen von Leguminosen mit symbiotischen Bakterien (Rhizobium) und symbiotischen Pilzen (vesikulaer-arbuskulaere Mycorrhiza) wurden als empfindliche Bioindikatoren gegenueber bodenbelastenden Altstoffen nachgewiesen. Fuer verschiedene Kulturpflanzen wurden unterschiedliche Transferraten aus dem Boden in die Pflanzenmatrix nachgewiesen. Gegenueber Schwermetallen (Cadmium, Blei, Arsenit) reagieren die Symbiosen sehr unterschiedlich. Als Altstoffe wurden modellhaft Chinolin, Fluoranthen, Phenanthren und Anthrazen verwendet. (orig.)

  8. Fungal genes related to calcium homeostasis and signalling are upregulated in symbiotic arbuscular mycorrhiza interactions.

    Science.gov (United States)

    Liu, Yi; Gianinazzi-Pearson, Vivienne; Arnould, Christine; Wipf, Daniel; Zhao, Bin; van Tuinen, Diederik

    2013-01-01

    Fluctuations in intracellular calcium levels generate signalling events and regulate different cellular processes. Whilst the implication of Ca(2+) in plant responses during arbuscular mycorrhiza (AM) interactions is well documented, nothing is known about the regulation or role of this secondary messenger in the fungal symbiont. The spatio-temporal expression pattern of putatively Ca(2+)-related genes of Glomus intraradices BEG141 encoding five proteins involved in membrane transport and one nuclear protein kinase, was investigated during the AM symbiosis. Expression profiles related to successful colonization of host roots were observed in interactions of G. intraradices with roots of wild-type Medicago truncatula (line J5) compared to the mycorrhiza-defective mutant dmi3/Mtsym13. Symbiotic fungal activity was monitored using stearoyl-CoA desaturase and phosphate transporter genes. Laser microdissection based-mapping of fungal gene expression in mycorrhizal root tissues indicated that the Ca(2+)-related genes were differentially upregulated in arbuscules and/or in intercellular hyphae. The spatio-temporal variations in gene expression suggest that the encoded proteins may have different functions in fungal development or function during symbiosis development. Full-length cDNA obtained for two genes with interesting expression profiles confirmed a close similarity with an endoplasmic reticulum P-type ATPase and a Vcx1-like vacuolar Ca(2+) ion transporter functionally characterized in other fungi and involved in the regulation of cell calcium pools. Possible mechanisms are discussed in which Ca(2+)-related proteins G. intraradices BEG141 may play a role in mobilization and perception of the intracellular messenger by the AM fungus during symbiotic interactions with host roots. Copyright © 2012 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  9. Influence of arbuscular mycorrhizae on photosynthesis and water status of maize plants under salt stress.

    Science.gov (United States)

    Sheng, Min; Tang, Ming; Chen, Hui; Yang, Baowei; Zhang, Fengfeng; Huang, Yanhui

    2008-09-01

    The influence of arbuscular mycorrhizal (AM) fungus Glomus mosseae on characteristics of the growth, water status, chlorophyll concentration, gas exchange, and chlorophyll fluorescence of maize plants under salt stress was studied in the greenhouse. Maize plants were grown in sand and soil mixture with five NaCl levels (0, 0.5, 1.0, 1.5, and 2.0 g/kg dry substrate) for 55 days, following 15 days of non-saline pretreatment. Under salt stress, mycorrhizal maize plants had higher dry weight of shoot and root, higher relative chlorophyll content, better water status (decreased water saturation deficit, increased water use efficiency, and relative water content), higher gas exchange capacity (increased photosynthetic rate, stomatal conductance and transpiration rate, and decreased intercellular CO(2) concentration), higher non-photochemistry efficiency [increased non-photochemical quenching values (NPQ)], and higher photochemistry efficiency [increased the maximum quantum yield in the dark-adapted state (Fv/Fm), the maximum quantum yield in the light-adapted sate (Fv'/Fm'), the actual quantum yield in the light-adapted steady state (phiPSII) and the photochemical quenching values (qP)], compared with non-mycorrhizal maize plants. In addition, AM symbiosis could trigger the regulation of the energy biturcation between photochemical and non-photochemical events reflected in the deexcitation rate constants (kN, kN', kP, and kP'). All the results show that G. mosseae alleviates the deleterious effect of salt stress on plant growth, through improving plant water status, chlorophyll concentration, and photosynthetic capacity, while the influence of AM symbiosis on photosynthetic capacity of maize plants can be indirectly affected by soil salinity and mycorrhizae-mediated enhancement of water status, but not by the mycorrhizae-mediated enhancement of chlorophyll concentration and plant biomass.

  10. Mycorrhiza reduces adverse effects of dark septate endophytes (DSE) on growth of conifers.

    Science.gov (United States)

    Reininger, Vanessa; Sieber, Thomas N

    2012-01-01

    Mycorrhizal roots are frequently colonized by fungi of the Phialocephala fortinii s.l.-Acephala applanata species complex (PAC). These ascomycetes are common and widespread colonizers of tree roots. Some PAC strains reduce growth increments of their hosts but are beneficial in protecting roots against pathogens. Nothing is known about the effects of PAC on mycorrhizal fungi and the PAC-mycorrhiza association on plant growth, even though these two fungal groups occur closely together in natural habitats. We expect reduced colonization rates and reduced negative effects of PAC on host plants if roots are co-colonized by an ectomycorrhizal fungus (ECM). Depending on the temperature regime interactions among the partners in this tripartite ECM-PAC-plant system might also change. To test our hypotheses, effects of four PAC genotypes (two pathogenic and two non-pathogenic on the Norway spruce), mycorrhization by Laccaria bicolor (strain S238N) and two temperature regimes (19°C and 25°C) on the biomass of the Douglas-fir (Pseudotsuga menziesii) and Norway spruce (Picea abies) seedlings were studied. Mycorrhization compensated the adverse effects of PAC on the growth of the Norway spruce at both temperatures. The growth of the Douglas-fir was not influenced either by PAC or mycorrhization at 19°C, but at 25°C mycorrhization had a similar protective effect as in the Norway spruce. The compensatory effects probably rely on the reduction of the PAC-colonization density by mycorrhizae. Temperature and the PAC strain only had a differential effect on the biomass of the Norway spruce but not on the Douglas-fir. Higher temperature reduced mycorrhization of both hosts. We conclude that ectomycorrhizae form physical and/or physiological barriers against PAC leading to reduced PAC-colonization of the roots. Additionally, our results indicate that global warming could cause a general decrease of mycorrhization making primary roots more accessible to other symbionts and pathogens.

  11. Mycorrhiza reduces adverse effects of dark septate endophytes (DSE on growth of conifers.

    Directory of Open Access Journals (Sweden)

    Vanessa Reininger

    Full Text Available Mycorrhizal roots are frequently colonized by fungi of the Phialocephala fortinii s.l.-Acephala applanata species complex (PAC. These ascomycetes are common and widespread colonizers of tree roots. Some PAC strains reduce growth increments of their hosts but are beneficial in protecting roots against pathogens. Nothing is known about the effects of PAC on mycorrhizal fungi and the PAC-mycorrhiza association on plant growth, even though these two fungal groups occur closely together in natural habitats. We expect reduced colonization rates and reduced negative effects of PAC on host plants if roots are co-colonized by an ectomycorrhizal fungus (ECM. Depending on the temperature regime interactions among the partners in this tripartite ECM-PAC-plant system might also change. To test our hypotheses, effects of four PAC genotypes (two pathogenic and two non-pathogenic on the Norway spruce, mycorrhization by Laccaria bicolor (strain S238N and two temperature regimes (19°C and 25°C on the biomass of the Douglas-fir (Pseudotsuga menziesii and Norway spruce (Picea abies seedlings were studied. Mycorrhization compensated the adverse effects of PAC on the growth of the Norway spruce at both temperatures. The growth of the Douglas-fir was not influenced either by PAC or mycorrhization at 19°C, but at 25°C mycorrhization had a similar protective effect as in the Norway spruce. The compensatory effects probably rely on the reduction of the PAC-colonization density by mycorrhizae. Temperature and the PAC strain only had a differential effect on the biomass of the Norway spruce but not on the Douglas-fir. Higher temperature reduced mycorrhization of both hosts. We conclude that ectomycorrhizae form physical and/or physiological barriers against PAC leading to reduced PAC-colonization of the roots. Additionally, our results indicate that global warming could cause a general decrease of mycorrhization making primary roots more accessible to other symbionts

  12. Effects of Mycorrhizae on Carbon Cycling in Response to Extreme Drought

    Science.gov (United States)

    Ficken, C. D.; Warren, J.

    2016-12-01

    Plant-mycorrhizal symbioses are being increasingly accepted as drivers of ecosystem-level biogeochemical patterns and play an important role plant resource acquisition. Although some evidence suggests that mycorrhizal association increases plant drought-tolerance, direct comparisons of drought-resilience between mycorrhizal groups (i.e. arbuscular and ectomycorrhizal) are lacking. Indeed, soil CO2 pulses following dry-wet cycles are detectable at the ecosystem scale, but it remains unclear whether these pulses are driven by the activity of mycorrhizae or free-living microbes. These knowledge gaps hinder our ability to predict CO2 fluxes in the face of increased precipitation variability and have broad implications for understanding plant performance during, and recovery following, drought. We predicted that arbuscular mycorrhizae (AM) would be more resilient to drought than ectomycorrhizae (ECM) because narrower AM hyphae may access water from smaller soil pores and because AM produce a glycoprotein that increases soil aggregation. To compare the functioning of AM and ECM throughout drought, we examined soil respiration dynamics between AM- and ECM-dominated mesocosms throughout moderate and extreme drought. Mesocosms were partitioned with mesh dividers into chambers (roots+hyphae+microbes; hyphae+microbes; microbes only) to compare the relative functioning of biotic pools throughout drought. We found that respiration responses to drought differed substantially between AM and ECM-dominated systems. Under dry conditions, respiration from both root- and hyphal-exclusion chambers did not differ between AM and ECM mesocosms. In contrast, under wet conditions, respiration was significantly greater from AM than ECM mesocosms. Following rewetting, the respiration pulse in AM systems was largely due to to free-living microbes (+330% C flux above dry conditions), whereas in ECM systems there was a proportionally greater increase from mycorrhizal chambers (+130%). This

  13. Mycorrhiza Reduces Adverse Effects of Dark Septate Endophytes (DSE) on Growth of Conifers

    Science.gov (United States)

    Reininger, Vanessa; Sieber, Thomas N.

    2012-01-01

    Mycorrhizal roots are frequently colonized by fungi of the Phialocephala fortinii s.l. – Acephala applanata species complex (PAC). These ascomycetes are common and widespread colonizers of tree roots. Some PAC strains reduce growth increments of their hosts but are beneficial in protecting roots against pathogens. Nothing is known about the effects of PAC on mycorrhizal fungi and the PAC-mycorrhiza association on plant growth, even though these two fungal groups occur closely together in natural habitats. We expect reduced colonization rates and reduced negative effects of PAC on host plants if roots are co-colonized by an ectomycorrhizal fungus (ECM). Depending on the temperature regime interactions among the partners in this tripartite ECM-PAC-plant system might also change. To test our hypotheses, effects of four PAC genotypes (two pathogenic and two non-pathogenic on the Norway spruce), mycorrhization by Laccaria bicolor (strain S238N) and two temperature regimes (19°C and 25°C) on the biomass of the Douglas-fir (Pseudotsuga menziesii) and Norway spruce (Picea abies) seedlings were studied. Mycorrhization compensated the adverse effects of PAC on the growth of the Norway spruce at both temperatures. The growth of the Douglas-fir was not influenced either by PAC or mycorrhization at 19°C, but at 25°C mycorrhization had a similar protective effect as in the Norway spruce. The compensatory effects probably rely on the reduction of the PAC-colonization density by mycorrhizae. Temperature and the PAC strain only had a differential effect on the biomass of the Norway spruce but not on the Douglas-fir. Higher temperature reduced mycorrhization of both hosts. We conclude that ectomycorrhizae form physical and/or physiological barriers against PAC leading to reduced PAC-colonization of the roots. Additionally, our results indicate that global warming could cause a general decrease of mycorrhization making primary roots more accessible to other symbionts and

  14. Soil conditions moderate the effects of herbivores, but not mycorrhizae, on a native bunchgrass

    Science.gov (United States)

    Connolly, Brian M.; Orrock, John L.; Witter, Martha S.

    2016-11-01

    Herbivores, microbial mutualists, and soil nutrients can affect plant survival, growth, and reproduction, demographic parameters that are essential to plant restoration. In this study we ask: 1) whether native plants that form early associations with mycorrhizal fungi are more tolerant of mammalian grazers, and 2) how early plant associations with mycorrhizal fungi influence mammalian grazing across gradients in soil nutrients. In eight grassland sites in California (USA), we transplanted seedlings of a native bunchgrass, Stipa pulchra, that were or were not pretreated with mycorrhizal fungi in exclosures designed to exclude different guilds of vertebrate grazers. Pretreated plants had greater establishment eight months after transplantation than untreated plants. Mycorrhizal inoculation resulted in twofold greater biomass and fourfold greater seed production when plants were protected from herbivores; inoculation with mycorrhizae resulted in twofold greater biomass and seed production when plants were accessible by all herbivores. Soil phosphate and potassium concentrations influenced herbivory: vertebrate grazing had less effect on transplant biomass and seed production at sites with high phosphate - low potassium soils, but the effects of grazing were more severe in low phosphate - high potassium soils. Pretreatment with mycorrhizal fungi can result in greater survival, growth, and reproduction of transplanted seedlings of native bunchgrass S. pulchra. Our results also illustrate that soil conditions may influence the extent to which the vertebrate herbivore community limits restoration of S. pulchra: the effects of some small mammalian herbivores (e.g., voles) was little affected by soil conditions, but grazing by larger herbivores had a greater effect on S. pulchra performance at sites with low phosphate - high potassium soils. In helping identify the contribution of soil nutrients, herbivores, and mycorrhizae to establishment and performance, our work has

  15. Arbuscular mycorrhiza fungi mediate soil respiration response to climate change in California grasslands

    Science.gov (United States)

    Estruch, Carme; Mcfarland, Jack; Haw, Monica P.; Schulz, Marjorie S.; Pugnaire, Francisco I.; Waldrop, Mark P.

    2017-04-01

    California grasslands store ca. 100 Tg of soil organic carbon (SOC) and almost 40% of those ecosystems are prone to land use changes. The fate of these carbon pools will largely depend on how the main components of soil respiration - i.e., roots, mycorrhiza, and 'bulk soil' communities- respond to such changes. In order to determine the sensitivity to environmental drivers we set up an experiment to address the effect of plant community composition, soil age and warming on soil respiration rate during the 2014-2015 winter. We tested differences among microbial, fungal and root respiration using an exclusion technique to assess the effect of plant community (open grasslands vs oak woodland) in two field sites differing in soil properties as nutrient content, related to geologic soil age (92 and 137 kyr). We also used open top chambers (OTC) to simulate global change effects on grasslands. Our results showed that arbuscular mycorrhizal fungi were the main drivers of differences recorded between soils of different age, and that those differences were linked to nutrient availability. Bulk soil respiration was more sensitive to environmental variation than mycorrhizal or root respiration, indicating that the presence of mycorrhizae and roots can regulate the capacity of CO2 emission to the atmosphere. Soil age affected CO2 flux from grasslands but not under oak canopies, likely due to the high concentration of SOM in oak canopies which moderated any affect of soil mineralogy on nutrient availability. Overall our study shows that the ability of grasslands to mitigate CO2 emissions depends on interactions between vegetation and their rhizosphere on soil microbial communities.

  16. Root development during soil genesis: effects of root-root interactions, mycorrhizae, and substrate

    Science.gov (United States)

    Salinas, A.; Zaharescu, D. G.

    2015-12-01

    A major driver of soil formation is the colonization and transformation of rock by plants and associated microbiota. In turn, substrate chemical composition can also influence the capacity for plant colonization and development. In order to better define these relationships, a mesocosm study was set up to analyze the effect mycorrhizal fungi, plant density and rock have on root development, and to determine the effect of root morphology on weathering and soil formation. We hypothesized that plant-plant and plant-fungi interactions have a stronger influence on root architecture and rock weathering than the substrate composition alone. Buffalo grass (Bouteloua dactyloides) was grown in a controlled environment in columns filled with either granular granite, schist, rhyolite or basalt. Each substrate was given two different treatments, including grass-microbes and grass-microbes-mycorrhizae and incubated for 120, 240, and 480 days. Columns were then extracted and analyzed for root morphology, fine fraction, and pore water major element content. Preliminary results showed that plants produced more biomass in rhyolite, followed by schist, basalt, and granite, indicating that substrate composition is an important driver of root development. In support of our hypothesis, mycorrhizae was a strong driver of root development by stimulating length growth, biomass production, and branching. However, average root length and branching also appeared to decrease in response to high plant density, though this trend was only present among roots with mycorrhizal fungi. Interestingly, fine fraction production was negatively correlated with average root thickness and volume. There is also slight evidence indicating that fine fraction production is more related to substrate composition than root morphology, though this data needs to be further analyzed. Our hope is that the results of this study can one day be applied to agricultural research in order to promote the production of crops

  17. The importance of arbuscular mycorrhiza for Cyclamen purpurascens subsp. immaculatum endemic in Slovakia.

    Science.gov (United States)

    Rydlová, Jana; Sýkorová, Zuzana; Slavíková, Renata; Turis, Peter

    2015-11-01

    At present, there is no relevant information on arbuscular mycorrhiza and the effect of the symbiosis on the growth of wild populations of cyclamens. To fill this gap, two populations of Cyclamen purpurascens subsp. immaculatum, endemic in Nízke Tatry (NT) mountains and Veľká Fatra (VF) mountains, Slovakia, were studied in situ as well as in a greenhouse pot experiment. For both populations, mycorrhizal root colonization of native plants was assessed, and mycorrhizal inoculation potential (MIP) of the soils at the two sites was determined in 3 consecutive years. In the greenhouse experiment, the growth response of cyclamens to cross-inoculation with arbuscular mycorrhizal fungi (AMF) was tested: plants from both sites were grown in their native soils and inoculated with a Septoglomus constrictum isolate originating either from the same or from the other plant locality. Although the MIP of soil at the NT site was significantly higher than at the VF site, the level of AMF root colonization of C. purpurascens subsp. immaculatum plants in the field did not significantly differ between the two localities. In the greenhouse experiment, inoculation with AMF generally accelerated cyclamen growth and significantly increased all growth parameters (shoot dry weight, leaf number and area, number of flowers, tuber, and root dry weight) and P uptake. The two populations of C. purpurascens subsp. immaculatum grown in their native soils, however, differed in their response to inoculation. The mycorrhizal growth response of NT plants was one-order higher compared to VF plants, and all their measured growth parameters were stimulated regardless of the fungal isolates' origin. In the VF plants, only the non-native (NT originating) isolate showed a significant positive effect on several growth traits. It can be concluded that mycorrhiza significantly increased fitness of C. purpurascens subsp. immaculatum, despite the differences between plant populations, implying that AMF

  18. Arbuscular mycorrhizae formed by Penicillium pinophilum improve the growth, nutrient uptake and photosynthesis of strawberry with two inoculum-types.

    Science.gov (United States)

    Fan, Yongqiang; Luan, Yushi; An, Lijia; Yu, Kun

    2008-08-01

    Penicillium pinophilum was isolated from the soil in a commercial strawberry field. The strain readily formed arbuscular mycorrhizae (AM) with the roots of strawberry 'Zoji' (Fragaria x ananassa Duch. CV.) when plants were inoculated with either fresh cultured hyphae or root/soil mixtures. Fresh hyphae, however, resulted in higher amounts of colonization than root/soil inoculum. Compared with uninoculated strawberries, inoculation increased plant dry weight by 31%, as well as nitrogen content (47%), phosphorus content (57%), and photosynthetic rate (71%). AM inoculation also shortened the blossom and ripening date by 3 and 4 days, respectively. This is the first report of a P. pinophilum strain resulting in mycorrhiza with strawberry roots. The significant advantages of this strain are that it is easy to culture and inoculation of plants results in significant growth benefits that may be useful in strawberry production.

  19. Uptake and speciation of selenium in garlic cultivated in soil amended with symbiotic fungi (mycorrhiza) and selenate

    Energy Technology Data Exchange (ETDEWEB)

    Larsen, Erik H.; Hansen, Marianne; Rasmussen, Peter Have; Sloth, Jens J. [Danish Institute for Food and Veterinary Research, Department of Food Chemistry, Soeborg (Denmark); Lobinski, Ryszard; Ruzik, Rafal; Mazurowska, Lena [CNRS UMR 5034, Pau (France); Warsaw University of Technology, Department of Analytical Chemistry, Warsaw (Poland); Burger-Meyer, Karin; Scholten, Olga [Wageningen University and Research Centre, Plant Research International (PRI), P.O. Box 16, Wageningen (Netherlands); Kik, Chris [Wageningen University and Research Centre, Plant Research International (PRI), P.O. Box 16, Wageningen (Netherlands); Wageningen University and Research Centre, Centre for Genetic Resources, The Netherlands (CGN), P.O. Box 16, Wageningen (Netherlands)

    2006-07-15

    The scope of the work was to investigate the influence of selenate fertilisation and the addition of symbiotic fungi (mycorrhiza) to soil on selenium and selenium species concentrations in garlic. The selenium species were extracted from garlic cultivated in experimental plots by proteolytic enzymes, which ensured liberation of selenium species contained in peptides or proteins. Separate extractions using an aqueous solution of enzyme-deactivating hydroxylamine hydrochloride counteracted the possible degradation of labile selenium species by enzymes (such as alliinase) that occur naturally in garlic. The selenium content in garlic, which was analysed by ICP-MS, showed that addition of mycorrhiza to the natural soil increased the selenium uptake by garlic tenfold to 15 {mu}g g{sup -1} (dry mass). Fertilisation with selenate and addition of mycorrhiza strongly increased the selenium content in garlic to around one part per thousand. The parallel analysis of the sample extracts by cation exchange and reversed-phase HPLC with ICP-MS detection showed that {gamma}-glutamyl-Se-methyl-selenocysteine amounted to 2/3, whereas methylselenocysteine, selenomethionine and selenate each amounted to a few percent of the total chromatographed selenium in all garlic samples. Se-allyl-selenocysteine and Se-propyl-selenocysteine, which are selenium analogues of biologically active sulfur-containing amino acids known to occur in garlic, were searched for but not detected in any of the extracts. The amendment of soil by mycorrhiza and/or by selenate increased the content of selenium but not the distribution of detected selenium species in garlic. Finally, the use of two-dimensional HPLC (size exclusion followed by reversed-phase) allowed the structural characterisation of {gamma}-glutamyl-Se-methyl-selenocysteine and {gamma}-glutamyl-Se-methyl-selenomethionine in isolated chromatographic fractions by quadrupole time-of-flight mass spectrometry. (orig.)

  20. Effect of mycorrhizae, Thiobacillus and sulfur nutrition on the chemical composition of soybean [Glycine max (L.)] Merr. seed.

    Science.gov (United States)

    Mostafavian, S R; Pirdashti, H; Ramzanpour, M R; Andarkhor, A A; Shahsavari, A

    2008-03-15

    A field experiment carried out in a calcareous soil with a low available phosphorus to evaluate effectiveness of biofertilizers, mycorrhizae (Glomus intraradices) and Thiobacillus sp. inoculation individually or in combination on seed yield, oil, protein and some elements (P, Fe, Mn, Zn) concentration in two soybean [Glycine max (L.) Merr.] cultivars. The applied treatments were different fertilizers with 6 levels (including: NP (control, 12 kg N ha(-1) as urea, 46 kg P2O5 ha(-1) as triple super phosphate); NPK (NP + 75 kg K2O ha(-1) as potassium sulphate); NPKS [NPK+ S (100 kg S ha(-1))]; NPKST (NPKS + seed inoculation with Thiobacillus bacteria); NPKM (NPK + Seed inoculation with mycorrhizae fungi) and NPKSTM (NPKS + seed inoculation with Thiobacillus and mycorrhizae) and two cultivars (JK and 032). Before planting, soybean seeds were inoculated by Bradyrhizobium japonicum in all treatments. Results showed that combined inoculation of biofertilizers increased yield, however the highest yield was observed in treatment NPKST. Increasing oil content (percentage) was more pronounced in treatments NPKM, while most protein content (percentage) increasing was observed in NPKS and NPKM. Fe and Zn concentrations were unaffected significantly by fertilizer treatments, but NPKSTM showed significantly higher value of seed's Mn concentration compared to treatments NP and NPK. Although no significant difference was observed in terms ofP concentration of 032 line among fertilizer treatments, JK cultivar and NPKSTM caused a significant increasing in P concentration compared to NP, NPKS and NPKM. Present results suggested that applying biofertilizers i.e., mycorrhizae and Thiobacillus increased soybean yield compared to control (NP). Overall, this study demonstrated that soybean seed yield and its chemical composition could be affected by biofertilizer inoculation.

  1. Effects of different mycorrhiza species on grain yield, nutrient uptake and oil content of sunflower under water stress

    OpenAIRE

    Mostafa Heidari; Vahid Karami

    2014-01-01

    The role of arbuscular mycorrhizal fungi in alleviating water stress is well documented. In order to study the effects of water stress and two different mycorrhiza species on grain yield, nutrient uptake and oil content of sunflower, a field experiment as split plot design with three replications was conducted in the Research Field Station, Zabol University, Zabol, Iran in 2011. Water stress treatments included control as 90% of field capacity (W1), 70% field capacity (W2) and 50% field capac...

  2. Mycorrhiza-plant colonization patterns on a subalpine glacier forefront as a model system of primary succession.

    Science.gov (United States)

    Cázares, Efrén; Trappe, James M; Jumpponen, Ari

    2005-09-01

    Lyman glacier in the North Cascades Mountains of Washington has a subalpine forefront characterized by a well-developed terminal moraine, inconspicuous successional moraines, fluting, and outwash. These deposits were depleted of symbiotic fungi when first exposed but colonized by them over time after exposure. Four major groups of plant species in this system are (1) mycorrhiza-independent or facultative mycotrophic, (2) dependent on arbuscular mycorrhizae (AM) (3) dependent on ericoid mycorrhiza (ERM) or ectomycorrhizae (EM), and (4) colonized by dark-septate (DS) endophytes. We hypothesized that availability of mycorrhizal propagules was related to the success of mycorrhiza-dependent plants in colonizing new substrates in naturally evolved ecosystems. To test this hypothesis roots samples of 66 plant species were examined for mycorrhizal colonization. The plants were sampled from communities at increasing distances from the glacier terminus to compare the newest communities with successively older ones. Long established, secondary successional dry meadow communities adjacent to the glacier forefront, and nearby high alpine communities were sampled for comparison. DS were common on most plant species on the forefront. Nonmycorrhizal plants predominated in the earlier successional sites, whereas the proportion of mycorrhizal plants generally increased with age of community. AM were present, mostly at low levels, and nearly absent in two sites of the forefront. ERM were present in all species of Ericaceae sampled, and EM in all species of Pinaceae and Salicaceae. Roots of plants in the long established meadow and heath communities adjacent to the forefront and the high alpine community all had one or another of the colonization types, with DS and AM predominating.

  3. Seedling mycorrhiza

    DEFF Research Database (Denmark)

    Rasmussen, Hanne Nina; Rasmussen, Finn N.

    2014-01-01

    rhizoctonious mycelia are presently involved in OSM, presumably evolving secondarily and often in parallel in different orchid clades. Structural features and internal patterns of mycobiont behaviour appear to have remained largely the same, implying that OSM needs only minor physiological adjustment...

  4. Mycorrhiza analyses in New Zealand truffières reveal frequent but variable persistence of Tuber melanosporum in co-existence with other truffle species.

    Science.gov (United States)

    Guerin-Laguette, Alexis; Cummings, Nicholas; Hesom-Williams, Nina; Butler, Ruth; Wang, Yun

    2013-02-01

    This study compiles the results from an examination of mycorrhizae on root samples from Tuber melanosporum truffières in New Zealand. Samples were taken over 5 years from 328 trees in 43 truffières established with nursery-inoculated trees. Mycorrhizae were analysed using a combination of morphological and molecular techniques, focusing on the identification of Tuber species. Results show that 49% of the trees, and nearly 90% of the truffières, retained T. melanosporum mycorrhizae up to 21 years after planting. Tuber mycorrhizae with spiky cystidia were found on 26.9% of the tested trees: Tuber brumale (5.5%), Tuber maculatum (10.7%), and unidentified Tuber species (10.7%), and were detected in 67% of the truffières tested. T. brumale was found in 28% and T. maculatum in 35% of the truffières. In 56% of the truffières, T. melanosporum was found to occur with spiky Tuber species. The existence of T. brumale and T. maculatum in the same truffière was recorded only once. Forty-four percent of trees examined had Scleroderma-like (SCL) mycorrhizae and 50% of trees hosted other ectomycorrhizal species (OE). For all categories of mycorrhizal species examined, the variation between truffières was greater than variation within each truffière. Overall results indicate that Corylus avellana tends to be more receptive to mycorrhizae of Tuber species than Quercus robur but is not necessarily more productive. In productive truffières, Q. robur appears to host SCL mycorrhizae more often than C. avellana. This is the first study of its scale to analyse the mycorrhizal species associated with T. melanosporum truffières in the Southern Hemisphere.

  5. Effects of different mycorrhiza species on grain yield, nutrient uptake and oil content of sunflower under water stress

    Directory of Open Access Journals (Sweden)

    Mostafa Heidari

    2014-01-01

    Full Text Available The role of arbuscular mycorrhizal fungi in alleviating water stress is well documented. In order to study the effects of water stress and two different mycorrhiza species on grain yield, nutrient uptake and oil content of sunflower, a field experiment as split plot design with three replications was conducted in the Research Field Station, Zabol University, Zabol, Iran in 2011. Water stress treatments included control as 90% of field capacity (W1, 70% field capacity (W2 and 50% field capacity (W3 assigned to the main plots and two different mycorrhiza species, consisting of M1 = control (without any inoculation, M2 = Glumus mossea and M3 = Glumus etanicatum as sub plots. Results showed that by increasing water stress from control (W1 to W3 treatment, grain yield was significantly decreased. The reduction in the level of W3 was 15.05%. The content of potassium in seeds significantly decreased due to water stress but water stress upto W2 treatment increased the content of phosphorus, nitrogen and oil content of seeds. In between two species of mycorrhiza in sunflower plants, Glumus etanicatum had the highest effect on grain yield and these elements in seeds and increased both.

  6. Effects of Arbuscular Mycorrhiza on Osmotic Adjustment and Photosynthetic Physiology of Maize Seedlings in Black Soils Region of Northeast China

    Directory of Open Access Journals (Sweden)

    Hongwen Xu

    Full Text Available ABSTRACT To investigate the effect of arbuscular mycorrhiza fungi on maize growth, osmoregulation substances and photosynthetic physiology, a popular maize variety ZD 958 was measured under potted condition. Arbuscular mycorrhiza (AM symbiosis promoted plant growth, and enhanced plant height, leaf length, mean leaf width and dry weight. Higher soluble sugar and protein, but lower proline concentrations were detected in AM seedlings than corresponding non-AM seedlings. Quantum yield of PSII photochemistry and potential photochemical efficiency increased by arbuscular mycorrhiza fungi, meanwhile, AM plants had lower primary fluorescence but higher maximal fluorescence and variable fluorescence than non-AM plants. AM enhanced apparent quantum efficiency, maximum net photosynthetic rate, dark respiration rate and light saturation point, but reduced light compensation point. The conclusion was that, after the seedling inoculated with Glomus. tortuosum, AM symbioses could protect cell from being hurt through regulating substances related to osmotic adjustment, besides, the efficiency of light utilization, the capacity of using low light and the capacity of fitting and using high light were all increased by AM symbiosis.

  7. Atractiellomycetes belonging to the ‘rust’ lineage (Pucciniomycotina) form mycorrhizae with terrestrial and epiphytic neotropical orchids

    Science.gov (United States)

    Kottke, Ingrid; Suárez, Juan Pablo; Herrera, Paulo; Cruz, Dario; Bauer, Robert; Haug, Ingeborg; Garnica, Sigisfredo

    2010-01-01

    Distinctive groups of fungi are involved in the diverse mycorrhizal associations of land plants. All previously known mycorrhiza-forming Basidiomycota associated with trees, ericads, liverworts or orchids are hosted in Agaricomycetes, Agaricomycotina. Here we demonstrate for the first time that Atractiellomycetes, members of the ‘rust’ lineage (Pucciniomycotina), are mycobionts of orchids. The mycobionts of 103 terrestrial and epiphytic orchid individuals, sampled in the tropical mountain rainforest of Southern Ecuador, were identified by sequencing the whole ITS1-5.8S-ITS2 region and part of 28S rDNA. Mycorrhizae of 13 orchid individuals were investigated by transmission electron microscopy. Simple septal pores and symplechosomes in the hyphal coils of mycorrhizae from four orchid individuals indicated members of Atractiellomycetes. Molecular phylogeny of sequences from mycobionts of 32 orchid individuals out of 103 samples confirmed Atractiellomycetes and the placement in Pucciniomycotina, previously known to comprise only parasitic and saprophytic fungi. Thus, our finding reveals these fungi, frequently associated to neotropical orchids, as the most basal living basidiomycetes involved in mycorrhizal associations of land plants. PMID:20007181

  8. Mycorrhiza of the host-specific Lactarius deterrimus on the roots of Picea abies and Arctostaphylos uva-ursi.

    Science.gov (United States)

    Mühlmann, O; Göbl, F

    2006-06-01

    The ectomycorrhizal basidiomycete species Lactarius deterrimus Gröger is considered to be a strictly host-specific mycobiont of Picea abies (L.) Karst. However, we identified arbutoid mycorrhiza formed by this fungus on the roots of Arctostaphylos uva-ursi (L.) Spreng. in a mixed stand at the alpine timberline; typical ectomycorrhiza of P. abies were found in close relation. A. uva-ursi is known as an extremely unspecific phytobiont. The mycorrhizae of both associations are described and compared morphologically. The mycorrhiza formed by L. deterrimus on both A. uva-ursi and P. abies show typical ectomycorrhizal features such as a hyphal mantle and a Hartig net. The main difference between the mycorrhizal symbioses with the different phytobionts is the occurrence of intracellular hyphae in the epidermal cells of A. uva-ursi. This emphasizes the importance of the plant partner for mycorrhizal anatomy. This is the first report of a previously considered host-specific ectomycorrhizal fungus in association with A. uva-ursi under natural conditions. The advantages of this loose specificity between the fungus and plant species is discussed.

  9. Symbiosis-related pea genes modulate fungal and plant gene expression during the arbuscule stage of mycorrhiza with Glomus intraradices.

    Science.gov (United States)

    Kuznetsova, Elena; Seddas-Dozolme, Pascale M A; Arnould, Christine; Tollot, Marie; van Tuinen, Diederik; Borisov, Alexey; Gianinazzi, Silvio; Gianinazzi-Pearson, Vivienne

    2010-08-01

    The arbuscular mycorrhiza association results from a successful interaction between genomes of the plant and fungal symbiotic partners. In this study, we analyzed the effect of inactivation of late-stage symbiosis-related pea genes on symbiosis-associated fungal and plant molecular responses in order to gain insight into their role in the functional mycorrhizal association. The expression of a subset of ten fungal and eight plant genes, previously reported to be activated during mycorrhiza development, was compared in Glomus intraradices-inoculated wild-type and isogenic genotypes of pea mutated for the PsSym36, PsSym33, and PsSym40 genes where arbuscule formation is inhibited or fungal turnover modulated, respectively. Microdissection was used to corroborate arbuscule-related fungal gene expression. Molecular responses varied between pea genotypes and with fungal development. Most of the fungal genes were downregulated when arbuscule formation was defective, and several were upregulated with more rapid fungal development. Some of the plant genes were also affected by inactivation of the PsSym36, PsSym33, and PsSym40 loci, but in a more time-dependent way during root colonization by G. intraradices. Results indicate a role of the late-stage symbiosis-related pea genes not only in mycorrhiza development but also in the symbiotic functioning of arbuscule-containing cells.

  10. Arbuscular mycorrhiza Symbiosis Induces a Major Transcriptional Reprogramming of the Potato SWEET Sugar Transporter Family.

    Science.gov (United States)

    Manck-Götzenberger, Jasmin; Requena, Natalia

    2016-01-01

    Biotrophic microbes feeding on plants must obtain carbon from their hosts without killing the cells. The symbiotic Arbuscular mycorrhizal (AM) fungi colonizing plant roots do so by inducing major transcriptional changes in the host that ultimately also reprogram the whole carbon partitioning of the plant. AM fungi obtain carbohydrates from the root cortex apoplast, in particular from the periarbuscular space that surrounds arbuscules. However, the mechanisms by which cortical cells export sugars into the apoplast for fungal nutrition are unknown. Recently a novel type of sugar transporter, the SWEET, able to perform not only uptake but also efflux from cells was identified. Plant SWEETs have been shown to be involved in the feeding of pathogenic microbes and are, therefore, good candidates to play a similar role in symbiotic associations. Here we have carried out the first phylogenetic and expression analyses of the potato SWEET family and investigated its role during mycorrhiza symbiosis. The potato genome contains 35 SWEETs that cluster into the same four clades defined in Arabidopsis. Colonization of potato roots by the AM fungus Rhizophagus irregularis imposes major transcriptional rewiring of the SWEET family involving, only in roots, changes in 22 of the 35 members. None of the SWEETs showed mycorrhiza-exclusive induction and most of the 12 induced genes belong to the putative hexose transporters of clade I and II, while only two are putative sucrose transporters from clade III. In contrast, most of the repressed transcripts (10) corresponded to clade III SWEETs. Promoter-reporter assays for three of the induced genes, each from one cluster, showed re-localization of expression to arbuscule-containing cells, supporting a role for SWEETs in the supply of sugars at biotrophic interfaces. The complex transcriptional regulation of SWEETs in roots in response to AM fungal colonization supports a model in which symplastic sucrose in cortical cells could be cleaved

  11. Arbuscular mycorrhiza symbiosis induces a major transcriptional reprogramming of the potato SWEET sugar transporter family

    Directory of Open Access Journals (Sweden)

    Jasmin eManck-Götzenberger

    2016-04-01

    Full Text Available Biotrophic microbes feeding on plants must obtain carbon from their hosts without killing the cells. The symbiotic arbuscular mycorrhizal (AM fungi colonizing plant roots do so by inducing major transcriptional changes in the host that ultimately also reprogram the whole carbon partitioning of the plant. AM fungi obtain carbohydrates from the root cortex apoplast, in particular from the periarbuscular space that surrounds arbuscules. However, the mechanisms by which cortical cells export sugars into the apoplast for fungal nutrition are unknown. Recently a novel type of sugar transporter, the SWEET, able to perform not only uptake but also efflux from cells was identified. Plant SWEETs have been shown to be involved in the feeding of pathogenic microbes and are, therefore, good candidates to play a similar role in symbiotic associations. Here we have carried out the first phylogenetic and expression analyses of the potato SWEET family and investigated its role during mycorrhiza symbiosis. The potato genome contains 35 SWEETs that cluster into the same four clades defined in Arabidopsis. Colonization of potato roots by the AM fungus Rhizophagus irregularis imposes major transcriptional rewiring of the SWEET family involving, only in roots, changes in 22 of the 35 members. None of the SWEETs showed mycorrhiza-exclusive induction and most of the twelve induced genes belong to the putative hexose transporters of clade I and II, while only two are putative sucrose transporters from clade III. In contrast, most of the repressed transcripts (10 corresponded to clade III SWEETs. Promoter-reporter assays for three of the induced genes, each from one cluster, showed re-localization of expression to arbuscule-containing cells, supporting a role for SWEETs in the supply of sugars at biotrophic interfaces. The complex transcriptional regulation of SWEETs in roots in response to AM fungal colonization supports a model in which symplastic sucrose in cortical

  12. Response of free-living soil protozoa and microorganisms to elevated atmospheric CO2 and presence of mycorrhiza

    DEFF Research Database (Denmark)

    Rønn, R.; Gavito, M.; Larsen, J.

    2002-01-01

    Possible interactions between mycorrhiza, atmospheric CO2, free-living soil microorganisms and protozoa were investigated in pot experimental systems. Pea plants (Pisum sativum L. cv. Solara) were grown under ambient (360 mul l(-1)) or elevated (700 mul l(-1)) atmospheric CO2 concentration...... with or without the presence of the arbuscular mycorrhizal (AM) fungus Glomus caledonium. It was hypothesised that (1) the populations of free-living soil protozoa would increase as a response to elevated CO2, (2) the effect of elevated CO2 on protozoa would be moderated by the presence of mycorrhiza and (3......) the presence of arbuscular mycorrhiza would affect soil protozoan numbers regardless of atmospheric CO2. After 3 weeks growth there was no difference in bacterial numbers (direct counts) in soil, but the number of free-living bacterial-feeding protozoa was significantly higher under elevated CO2...

  13. Arbuscular mycorrhiza and kinetic parameters of phosphorus absorption by bean plants

    Directory of Open Access Journals (Sweden)

    Silveira Adriana Parada Dias da

    2004-01-01

    Full Text Available The mechanisms that determine greater P absorption by mycorrhizal plants are still not completely clear, and are attributed, in part, to an increase in the number of absorption sites promoted by the hyphae, and/or to a greater affinity of the colonized hypha or root carriers to P. The effect of mycorrhizae formed by Glomus etunicatum on the kinetic parameters of P absorption by the roots and on P influx in bean plants of the IAC-Carioca cultivar was evaluated, in two distinct plant development periods: at the onset of flowering and at the pod-filling stage (35 and 50 days after sowing, respectively. A mixture of sand and silica (9:1 was utilized as substrate and irrigated with nutrient solution. The kinetics assay was performed by the method of 32P depletion from the solution (depletion curve, using intact plants. Mycorrhization promoted greater growth and P absorption by bean plants, which was more conspicuously observed at the pod-filling stage. Mycorrhizal plants showed higher values of maximum ion uptake rate (Vmax and net P influx at the flowering stage. Lower minimum ion concentration (Cmin and Michaelis-Menten constant (Km values were verified in mycorrhizal plants at the pod-filling stage. Mycorrhizal plants also presented higher net P influx per plant, in both stages. Cmin was the kinetic parameter more intimately related to P absorption, and a significant correlation was obtained between this parameter and shoot P content and accumulation in bean plants.

  14. Effects of mycorrhiza on growth and essential oil production in selected aromatic plants

    Directory of Open Access Journals (Sweden)

    Waed Tarraf

    2015-09-01

    Full Text Available Arbuscular mycorrhizal (AM symbiosis is widely investigated in aromatic herbs. Several studies have shown different effects on secondary metabolites, biomass production, as well as oil quantitative and qualitative aspects. The seeking to increase the yield of plants and their oils is an interesting topic in the world of medicinal and aromatic plant production. In tune with that, this study evaluated the effectiveness of two mycorrhiza fungi, Funneliformis mosseae (syn. Glomus mosseae and Septoglomus viscosum (syn. Glomus viscosum, on three species from Lamiaceae family: Salvia officinalis L., Origanum vulgare L., and Thymus vulgaris L. besides untreated control. It was found that the effect of symbiosis on growth was more favourable with S. viscosum than other AM fungus. The S. viscosum inoculation raised the yield of essential oil in oregano. Analysis of gas chromatography/mass spectrometry showed that manool obtained the highest abundance in leaf essential oil of inoculated sage; thymol was the major component whatever the treatment in thyme and lower relative content of carvacrol was reported with arbuscular mycorrhizal fungi inoculation in oregano. The results suggest the mycorrhizal inoculation as a promising technology in sustainable agricultural system to improve the plant productivity performance. Specific inocula are strategic to enhance the chemical profile of essential oils.

  15. The Role of Mycorrhiza in Drought Tolerance of Marigold (Calendula officinalis L.

    Directory of Open Access Journals (Sweden)

    Sh. Moghadasan

    2016-01-01

    Full Text Available To study the effect of mycorrhizal symbiosis and drought stress on marigold, a factorial experiment in a completely randomized design with three replications was conducted at the Plant Research Laboratory of Islamic Azad University, Neyshabur branch in 2014. The first factor consisted of application and non-application of mycorrhiza (Glomus intraradices and the second factor consisted of drought stress with three levels (irrigation based on 100%, 75% and 50% of field capacity. The results showed that growth parameters like plant height, leaf number, leaf area, root, shoot dry/fresh weight, Chla and Chlb content were significantly decreased by drought stress in both mycorrhizal and non-mycorrhizal plants. However, inoculation of plants by mycorrhizal fungus increased growth parameters and photosynthetic pigments as compared with non-mycorrhizal ones. Traits like RWC, potassium and phosphorus in response to drought stress were decreased. Inoculation of plant roots with Mycorrhizal fungi increased significantly RWC, potassium and phosphorus content of the plants under drought conditions as compared with non-inoculated plants. The results also showed the mycorrhizal symbiosis by Glomus intraradices improved drought tolerance of marigold through enhancing the absorption of water and mineral ions.

  16. Arbuscular mycorrhizas contribute to phytostabilization of uranium in uranium mining tailings

    Energy Technology Data Exchange (ETDEWEB)

    Chen Baodong [Department of Soil Environmental Science, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); Biosystems Department, Riso National Laboratory, Technical University of Denmark, DK-4000 Roskilde (Denmark); Roos, Per [Radiation Research Department, Technical University of Denmark, Riso National Laboratory, DK-4000 Roskilde (Denmark); Zhu Yongguan [Department of Soil Environmental Science, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); Jakobsen, Iver [Biosystems Department, Riso National Laboratory, Technical University of Denmark, DK-4000 Roskilde (Denmark)], E-mail: iver.jakobsen@risoe.dk

    2008-05-15

    Uranium (U) tailings pose environmental risks and call for proper remediation. In this paper medic and ryegrass plants were used as host plants to examine whether inoculation with an AM fungus, Glomus intraradices, would help phytostabilization of U tailings. The need of amending with uncontaminated soil for supporting plant survival was also examined by mixing soil with U tailing at different mixing ratios. Soil amendment increased plant growth and P uptake. Ryegrass produced a more extensive root system and a greater biomass than medic plants at all mixing ratios. Medic roots were extensively colonized by G. intraradices whereas ryegrass were more sparsely colonized. Plant growth was not improved by mycorrhizas, which, however, improved P nutrition of medic plants. Medic plants contained higher U concentrations and showed higher specific U uptake efficiency compared to ryegrass. In the presence of U tailing, most U had been retained in plant roots, and this distribution pattern was further enhanced by mycorrhizal colonization. The results suggest a role for AM fungi in phytostabilization of U tailings.

  17. A mycorrhiza helper bacterium enhances ectomycorrhizal and endomycorrhizal symbiosis of Australian Acacia species.

    Science.gov (United States)

    Duponnois, R; Plenchette, C

    2003-04-01

    The aims of this study were to test the effects of a mycorrhiza helper bacterium (MHB), Pseudomonas monteilii strain HR13 on the mycorrhization of (1) an Australian Acacia, A. holosericea, by several ectomycorrhizal fungi or one endomycorrhizal fungus Glomus intraradices, and (2) several Australian Acacia species by Pisolithus alba strain IR100 under glasshouse conditions. Bacterial inoculant HR13 significantly promoted ectomycorrhizal colonization for all the Acacia species, from 45.8% ( A. mangium) to 70.3% ( A. auriculiformis). A stimulating effect of HR13 on the ectomycorrhizal establishment was recorded with all the fungal isolates (strains of Pisolithus and Scleroderma). The same effect of bacteria on the frequency of endomycorrhizal colonization of A. holosericea seedlings by G. intraradices with vesicles and hyphae frequencies was recorded. The stimulation of saprophytic fungal growth by MHB is usually the main mechanism that could explain this bacterial effect on mycorrhizal establishment. MHB could stimulate the production of phenolic compounds such as hypaphorine and increase the aggressiveness of the fungal symbiont. However, no significant effect of MHB on fungal growth was recorded with Scleroderma isolates under axenic conditions but positive bacterial effects were observed with Pisolithus strains. From a practical viewpoint, it appears that MHB could stimulate the mycorrhizal colonization of Australian Acacia species with ectomycorrhizal or endomycorrhizal fungi, and could also facilitate controlled mycorrhization in nursery practices where Acacia species are grown for forestation purposes.

  18. Unravelling mycorrhiza-induced wheat susceptibility to the English grain aphid Sitobion avenae

    Science.gov (United States)

    Simon, Amma L.; Wellham, Peter A. D.; Aradottir, Gudbjorg I.; Gange, Alan C.

    2017-04-01

    Arbuscular mycorrhizal (AM) fungi are root symbionts that can increase or decrease aphid growth rates and reproduction, but the reason by which this happens is unknown. To investigate the underlying mechanisms of this interaction, we examined the effect of AM fungi on the English Grain aphid (Sitobion avenae) development, reproduction, attraction, settlement and feeding behaviour on two naturally susceptible varieties Triticum aestivum (L.) variety Solstice and T. monococcum MDR037, and two naturally resistant lines, T. monococcum MDR045 and MDR049. Mycorrhizal colonisation increased the attractiveness of T. aestivum var. Solstice to aphids, but there was no effect on aphid development on this variety. Using the Electrical Penetration Graph (EPG) technique, we found that mycorrhizal colonisation increased aphid phloem feeding on T. monococcum MDR037 and MDR045, colonisation also increased growth rate and reproductive success of S. avenae on these varieties. Mycorrhizas increased vascular bundle size, demonstrating that these fungi can influence plant anatomy. We discuss if and how this could be related to an enhanced success rate in phloem feeding in two varieties. Overall, we present and discuss how mycorrhizal fungi can affect the feeding behaviour of S. avenae in wheat, inducing susceptibility in a resistant variety.

  19. The Diversity of Arbuscular Mycorrhiza Fungus (AMF Indigenous in Peanuts (Arachis Hypogea LRhizosphere under Different Elevation

    Directory of Open Access Journals (Sweden)

    Surya Marizal

    2016-05-01

    Full Text Available Arbuscular Mycorrhiza Fungus (AMF is a type of soil microorganisms with obligate symbiotic characteristic. It can associate with high-level plants at the rate of 90%. Its association level highly depends on the type of AMF and the host plant. The lack of information about the AMF diversity in an ecosystem, and the insufficient number and types of isolates available, are limiting factors for the widespread use of AMF. It was a survey and observation research. In this research AMF indigenous potentials were observed in soil and roots of peanuts. Samples were taken from area with different elevation: low, medium, and high in West Sumatra. The study reveals that the highest number of AMF indigenous spores in peanuts rhizosphere from area with different elevation: low, medium, and high are dominated by Glomus sp.1 (159 spores, Acaulospora sp1 (110 spora and Glomus sp.2 (82 spores, however AMF indigenous with the highest percentage of existence is Glomus sp.1 and Acaulospora sp.1 (100%. In addition, the infectious level of AMF indigenous on roots of peanuts are 81.1%, 64,4% and 78,9% on low, medium and high elevation, respectively. The highest number of population and infectious level are on low elevation whereas the lowest number is on high elevation. Thus, the elevation level correlates with the type of infection, the size of population, and the percentage of infection.

  20. How membranes shape plant symbioses: Signaling and transport in nodulation and arbuscular mycorrhiza

    Directory of Open Access Journals (Sweden)

    Laure eBapaume

    2012-10-01

    Full Text Available As sessile organisms that cannot evade adverse environmental conditions, plants have evolved various adaptive strategies to cope with environmental stresses. One of the most successful adaptations is the formation of symbiotic associations with beneficial microbes. In these mutualistic interactions the partners exchange essential nutrients and improve their resistance to biotic and abiotic stresses. In arbuscular mycorrhiza (AM and in root nodule symbiosis (RNS, AM fungi and rhizobia, respectively, penetrate roots and accommodate within the cells of the plant host. In these endosymbiotic associations, both partners keep their plasma membranes intact and use them to control the bidirectional exchange of signaling molecules and nutrients. Intracellular accommodation requires the exchange of symbiotic signals and the reprogramming of both interacting partners. This involves fundamental changes at the level of gene expression and of the cytoskeleton, as well as of organelles such as plastids, endoplasmic reticulum (ER, and the central vacuole. Symbiotic cells are highly compartmentalized and have a complex membrane system specialized for the diverse functions in molecular communication and nutrient exchange. Here, we discuss the roles of the different cellular membrane systems and their symbiosis-related proteins in AM and RNS, and we review recent progress in the analysis of membrane proteins involved in endosymbiosis.

  1. The heavy metal paradox in arbuscular mycorrhizas: from mechanisms to biotechnological applications.

    Science.gov (United States)

    Ferrol, Nuria; Tamayo, Elisabeth; Vargas, Paola

    2016-12-01

    Arbuscular mycorrhizal symbioses that involve most plants and Glomeromycota fungi are integral and functional parts of plant roots. In these associations, the fungi not only colonize the root cortex but also maintain an extensive network of hyphae that extend out of the root into the surrounding environment. These external hyphae contribute to plant uptake of low mobility nutrients, such as P, Zn, and Cu. Besides improving plant mineral nutrition, arbuscular mycorrhizal fungi (AMF) can alleviate heavy metal (HM) toxicity to their host plants. HMs, such as Cu, Zn, Fe, and Mn, play essential roles in many biological processes but are toxic when present in excess. This makes their transport and homeostatic control of particular importance to all living organisms. AMF play an important role in modulating plant HM acquisition in a wide range of soil metal concentrations and have been considered to be a key element in the improvement of micronutrient concentrations in crops and in the phytoremediation of polluted soils. In the present review, we provide an overview of the contribution of AMF to plant HM acquisition and performance under deficient and toxic HM conditions, and summarize current knowledge of metal homeostasis mechanisms in arbuscular mycorrhizas. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  2. How membranes shape plant symbioses: signaling and transport in nodulation and arbuscular mycorrhiza

    Science.gov (United States)

    Bapaume, Laure; Reinhardt, Didier

    2012-01-01

    As sessile organisms that cannot evade adverse environmental conditions, plants have evolved various adaptive strategies to cope with environmental stresses. One of the most successful adaptations is the formation of symbiotic associations with beneficial microbes. In these mutualistic interactions the partners exchange essential nutrients and improve their resistance to biotic and abiotic stresses. In arbuscular mycorrhiza (AM) and in root nodule symbiosis (RNS), AM fungi and rhizobia, respectively, penetrate roots and accommodate within the cells of the plant host. In these endosymbiotic associations, both partners keep their plasma membranes intact and use them to control the bidirectional exchange of signaling molecules and nutrients. Intracellular accommodation requires the exchange of symbiotic signals and the reprogramming of both interacting partners. This involves fundamental changes at the level of gene expression and of the cytoskeleton, as well as of organelles such as plastids, endoplasmic reticulum (ER), and the central vacuole. Symbiotic cells are highly compartmentalized and have a complex membrane system specialized for the diverse functions in molecular communication and nutrient exchange. Here, we discuss the roles of the different cellular membrane systems and their symbiosis-related proteins in AM and RNS, and we review recent progress in the analysis of membrane proteins involved in endosymbiosis. PMID:23060892

  3. Terpenoids in plant and arbuscular mycorrhiza-reinforced defence against herbivorous insects.

    Science.gov (United States)

    Sharma, Esha; Anand, Garima; Kapoor, Rupam

    2017-03-01

    Plants, though sessile, employ various strategies to defend themselves against herbivorous insects and convey signals of an impending herbivore attack to other plant(s). Strategies include the production of volatiles that include terpenoids and the formation of symbiotic associations with fungi, such as arbuscular mycorrhiza (AM). This constitutes a two-pronged above-ground/below-ground attack-defence strategy against insect herbivores. Terpenoids represent an important constituent of herbivore-induced plant volatiles that deter herbivores and/or attract their predators. Terpenoids serve as airborne signals that can induce defence responses in systemic undamaged parts of the plant and also prime defence responses in neighbouring plants. Colonization of roots by AM fungi is known to influence secondary metabolism in plants; this includes alteration of the concentration and composition of terpenoids, which can boost both direct and indirect plant defence against herbivorous insects. Enhanced nutrient uptake facilitated by AM, changes in plant morphology and physiology and increased transcription levels of certain genes involved in the terpenoid biosynthesis pathway result in alterations in plant terpenoid profiles. The common mycorrhizal networks of external hyphae have added a dimension to the two-pronged plant defence strategy. These act as conduits to transfer defence signals and terpenoids. Improved understanding of the roles of terpenoids in plant and AM defences against herbivory and of interplant signalling in natural communities has significant implications for sustainable management of pests in agricultural ecosystems.

  4. Lime and phosphate application as mycorrhizae stimulation to enhance growth and yield of Marandu grass

    Directory of Open Access Journals (Sweden)

    Franklin Eduardo Melo Santiago

    2017-08-01

    Full Text Available Pastures are important food sources for Brazilian cattle herds. However, inadequate management of soil fertility has emerged as a major cause of low yield rates and of progressive degradation of these areas. The objective of the present study was to evaluate growth, by means of morphogenetic and structural characteristics, and yield of Brachiaria brizantha Stapf. cv. Marandu as functions of the application of the mycorrhizae stimulant formononetin, associated with lime and phosphate application. The experimental design was completely randomised with four replications, and the treatments were arranged in a 2 x 2 x 5 factorial scheme, consisting of two liming treatments (with and without limestone, two formononetin treatments (with and without application and five P2O5 doses (0, 25, 50, 100 and 200 mg dm-3. Three shoot cuttings were carried out after a first standardisation cutting to evaluate the morphogenetic and structural characteristics as well as the dry matter yield of different morphological fractions. Liming and phosphate application at the dose of 141 mg dm-3 P2O5 increased growth and yield of Marandu grass, and these practices are essential for the cultivation of this pasture grass in Yellow Latosol of the Cerrado region of Piauí, Brazil. The application of formononetin increased stem elongation rate, total number of tillers and green stem dry matter, and decreased dead dry matter of Marandu grass, which are effects that contribute to the improvement of pasture quality.

  5. Nitrogen fate and impacts in temperate forests: roles of mycorrhizae and pH

    Science.gov (United States)

    Goodale, Christine

    2017-04-01

    Chronic nitrogen deposition has long been expected to enhance forest carbon uptakeep and storage, although the magnitude and mechanisms of these responses have been uncertain and sometimes may vary by tree species or be confounded by other biogeochemical constraints. Recent results from a 15N tracer study in central New York State, USA, show that ectomycorrhizal tree species acquire more tracer than trees with arbuscular mycorrhizae, but that both types of trees take up only a small fraction of added N, acquired shortly after tracer addition. Most 15N remained in the soil, even five years after the addition. A recent N x pH addition experiment nearby shows that added N can slow decomposition, regardless of pH response, with greater responses in ectomycorrhizal than arbuscular dominated stands, and that some mature stands can also still increase growth. These results add to other observations from tracer and N addition studies as well as N deposition gradients and model analyses to improve estimates of the magnitude and persistence of ecosystem C storage in response to past and projected changes in atmospheric deposition.

  6. Evidence that northern pioneering pines with tuberculate mycorrhizae are unaffected by varying soil nitrogen levels.

    Science.gov (United States)

    Chapman, William Kenneth; Paul, Leslie

    2012-11-01

    Tuberculate mycorrhizae on Pinus contorta (lodgepole pine) have previously been shown to reduce acetylene, but an outstanding question has been to what degree these structures could meet the nitrogen requirements of the tree. We compared the growth, tissue nitrogen contents, and stable nitrogen isotope ratios of P. contorta growing in gravel pits to the same species growing on adjacent intact soil. Trees growing in severely nitrogen deficient gravel pits had virtually identical growth rates and tissue nitrogen contents to those growing on intact soil that had nitrogen levels typical for the area. δ(15)N values for trees in the gravel pits were substantially lower than δ(15)N values for trees on intact soil, and isotope ratios in vegetation were lower than the isotope ratios of the soil. The form of soil nitrogen in the gravel pits was almost exclusively nitrate, while ammonium predominated in the intact soil. Discrimination against (15)N during plant uptake of soil nitrate in the highly N-deficient soil should be weak or nonexistent. Therefore, the low δ(15)N in the gravel pit trees suggests that trees growing in gravel pits were using another nitrogen source in addition to the soil. Precipitation-borne nitrogen in the study area is extremely low. In conjunction with our other work, these findings strongly suggests that P. contorta and its microbial symbionts or associates fix nitrogen in sufficient amounts to sustain vigorous tree growth on the most nitrogen-deficient soils.

  7. Establishment of Desmoncus orthacanthos Martius (Arecaceae): effect of inoculation with arbuscular mycorrhizae.

    Science.gov (United States)

    Ramos-Zapata, José A; Orellana, Roger; Allen, Edith B

    2006-03-01

    Inoculation with arbuscular mycorrhizal (AM) fungi has often promoted increased growth of plants but very little work has been done in the tropics to evaluate the effects of inoculation on the establishment and development of seedlings in forests. Desmoncus orthacanthos Martius is a scandent palm present both in early and late succession, and consequently can be used in restoration processes. A test was conducted to determine the effect of AM on the establishment of Desmoncus orthacanthos in tropical forest in the Yucatan Peninsula, Mexico. Thirty inoculated and 30 non-inoculated seedlings were introduced in two sites of different successional age, a mature forest and an eight-year old abandoned cornfield (acahual). Survival and growth parameters were evaluated after 12 months. Leaf area and phosphorus, but not height, were greater in inoculated than non-inoculated plants in the forest but not in the acahual. However, mycorrhizae had a clear effect on plant survival in both sites, with a threefold increase in survival of inoculated compared with non-inoculated plants bassed on an odds ratio. The results suggest that inoculation will be important to increase the establishment of this commercially important palm.

  8. Infectivity of soilborne Frankia and mycorrhizae in Discaria trinervis along a vegetation gradient in Patagonian soil.

    Science.gov (United States)

    Chaia, Eugenia Esther; Fontenla, Sonia Beatriz; Vobis, Gernot; Wall, Luis Gabriel

    2006-01-01

    The infective capacities of the nitrogen fixing Actinomycete Frankia and arbuscular mycorrhizal fungi from soils near watercourses, along a vegetation gradient, were studied using plant bioassays. Frankia and arbuscular mycorrhizas capable of infecting Discaria trinervis were found at seventeen sites sampled. More specific enumeration of the infective capacities of both microorganisms in relation to environmental factors was performed in seven representative soils of the analysed vegetation zones (rainforest, xeric forest and steppe) using the most probable number method. The highest nodulation capacities ranged from 340 infective units g(-1 )soil, in a steppe marsh devoid of actinorhizas, to 61 in a coastal actinorhizal scrub (in xeric forest). The highest number of infective mycorrhizal units--also found in marsh--was 145. In general, rainforest soils had the lowest values for both microorganisms. Infective units of Frankia and arbuscular mycorrhizal fungi in soil were positively correlated (r = 0.89, P < 0.05). Both soilborne symbionts showed the highest infective capacity in semi-arid conditions nearby watercourse and at the valley bottom location. Tripartite symbiosis was effective in plants inoculated with steppe and xeric forest soils and plants inoculated with Frankia BCU110501 and Glomus mosseae. Interaction between both symbionts and influence of environmental conditions, in general, would contribute to define comparable trends of their infective capacities. ((c) 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim).

  9. Ostryopsis davidiana seedlings inoculated with ectomycorrhizal fungi facilitate formation of mycorrhizae on Pinus tabulaeformis seedlings.

    Science.gov (United States)

    Bai, Shu-Lan; Li, Guo-Lei; Liu, Yong; Kasten Dumroese, R; Lv, Rui-Heng

    2009-08-01

    Reforestation in China is important for reversing anthropogenic activities that degrade the environment. Pinus tabulaeformis is desired for these activities, but survival and growth of seedlings can be hampered by lack of ectomycorrhizae. When outplanted in association with Ostryopsis davidiana plants on reforestation sites, P. tabulaeformis seedlings become mycorrhizal and survival and growth are enhanced; without O. davidiana, pines often remain without mycorrhizae and performance is poorer. To better understand this relationship, we initiated an experiment using rhizoboxes that restricted root and tested the hypothesis that O. davidiana seedlings facilitated ectomycorrhizae formation on P. tabulaeformis seedlings through hyphal contact. We found that without O. davidiana seedlings, inocula of five indigenous ectomycorrhizal fungi were unable to grow and associate with P. tabulaeformis seedlings. Inocula placed alongside O. davidiana seedlings, however, resulted in enhanced growth and nutritional status of O. davidiana and P. tabulaeformis seedlings, and also altered rhizosphere pH and phosphatase activity. We speculate that these species form a common mycorrhizal network and this association enhances outplanting performance of P. tabulaeformis seedlings used for forest restoration.

  10. Effects of Arbuscular Mycorrhiza on Plant Chemistry and the Development and Behavior of a Generalist Herbivore.

    Science.gov (United States)

    Tomczak, Viktoria V; Schweiger, Rabea; Müller, Caroline

    2016-12-01

    Arbuscular mycorrhiza (AM) formed between plants and AM fungi (AMF) can alter host plant quality and thus influence plant-herbivore interactions. While AM is known to affect the development of generalist chewing-biting herbivores, AM-mediated impacts on insect behavior have been neglected until now. In this study, the effects of Rhizophagus irregularis, a generalist AMF, on phenotypic and leaf metabolic traits of Plantago major plants were investigated. Further, the influence of AM-mediated host plant modifications on the development and on seven behavioral traits of larvae of the generalist Mamestra brassicae were recorded. Tests were carried out in the third (L3) and fourth (L4) larval instar, respectively. While shoot water content, specific leaf area, and foliar concentrations of the secondary metabolite aucubin were higher in AM-treated compared to non-mycorrhized (NM) plants, lower concentrations of the primary metabolites citric acid and isocitric acid were found in leaves of AM plants. Larvae reared on AM plants gained a higher body mass and tended to develop faster than individuals reared on NM plants. However, plant treatment had no significant effect on any of the behavioral traits. Instead, differences between larvae of different ages were detected in several behavioral features, with L4 being less active and less bold than L3 larvae. The results demonstrate that AM-induced modifications of host plant quality influence larval development, whereas the behavioral phenotype seems to be more fixed at least under the tested conditions.

  11. A Medicago truncatula mutant hyper-responsive to mycorrhiza and defective for nodulation.

    Science.gov (United States)

    Morandi, Dominique; le Signor, Christine; Gianinazzi-Pearson, Vivienne; Duc, Gérard

    2009-08-01

    One key strategy for the identification of plant genes required for mycorrhizal development is the use of plant mutants affected in mycorrhizal colonisation. In this paper, we report a new Medicago truncatula mutant defective for nodulation but hypermycorrhizal for symbiosis development and response. This mutant, called B9, presents a poor shoot and, especially, root development with short laterals. Inoculation with Glomus intraradices results in significantly higher root colonisation of the mutant than the wild-type genotype A17 (+20% for total root length, +16% for arbuscule frequency in the colonised part of the root, +39% for arbuscule frequency in the total root system). Mycorrhizal effects on shoot and root biomass of B9 plants are about twofold greater than in the wild-type genotype. The B9 mutant of M. truncatula is characterised by considerably higher root concentrations of the phytoestrogen coumestrol and by the novel synthesis of the coumestrol conjugate malonyl glycoside, absent from roots of wild-type plants. In conclusion, this is the first time that a hypermycorrhizal plant mutant affected negatively for nodulation (Myc(++), Nod (-/+) phenotype) is reported. This mutant represents a new tool for the study of plant genes differentially regulating mycorrhiza and nodulation symbioses, in particular, those related to autoregulation mechanisms.

  12. Arbuscular mycorrhiza maintains nodule function during external NH4+ supply in Phaseolus vulgaris (L.).

    Science.gov (United States)

    Mortimer, Peter E; Pérez-Fernández, Maria A; Valentine, Alex J

    2012-04-01

    The synergistic benefits of the dual inoculation of legumes with nodule bacteria and arbuscular mycorrhizae (AM) are well established, but the effect of an external NH(4)(+) supply on this tripartite relationship is less clear. This effect of NH(4)(+) supply was investigated with regards to the growth and function of the legume host and both symbionts. Nodulated Phaseolus vulgaris seedlings with and without AM, were grown in a sand medium with either 0 N, 1 mM or 3 mM NH(4)(+). Plants were harvested at 30 days after emergence and measurements were taken for biomass, N(2) fixation, photosynthesis, asparagine concentration, construction costs and N nutrition. The addition of NH(4)(+) led to a decline in the percentage AM colonization and nodule dry weights, although AM colonization was affected to a lesser extent. NH(4)(+) supply also resulted in a decrease in the reliance on biological nitrogen fixation (BNF); however, the AM roots maintained higher levels of NH(4)(+) uptake than their non-AM counterparts. Furthermore, the non-AM plants had a higher production of asparagine than the AM plants. The inhibitory effects of NH(4)(+) on nodule function can be reduced by the presence of AM at moderate levels of NH(4)(+) (1 mM), via improving nodule growth or relieving the asparagine-induced inhibition of BNF. © Springer-Verlag 2011

  13. Arbuscular mycorrhiza formation in cordate gametophytes of two ferns, Angiopteris lygodiifolia and Osmunda japonica.

    Science.gov (United States)

    Ogura-Tsujita, Yuki; Sakoda, Aki; Ebihara, Atsushi; Yukawa, Tomohisa; Imaichi, Ryoko

    2013-01-01

    Mycorrhizal symbiosis is common among land plants including pteridophytes (monilophytes and lycophytes). In pteridophytes with diplohaplontic life cycle, mycorrhizal formations were mostly reported for sporophytes, but very few for gametophytes. To clarify the mycorrhizal association of photosynthetic gametophytes, field-collected gametophytes of Angiopteris lygodiifolia (Marattiaceae, n = 52) and Osmunda japonica (Osmundaceae, n = 45) were examined using microscopic and molecular techniques. Collected gametophytes were mostly cut into two pieces. One piece was used for light and scanning microscopic observations, and the other for molecular identification of plant species (chloroplast rbcL sequences) and mycorrhizal fungi (small subunit rDNA sequences). Microscopic observations showed that 96 % (50/52) of Angiopteris and 95 % (41/43) of Osmunda gametophytes contained intracellular hyphae with arbuscules and/or vesicles and fungal colonization was limited to the inner tissue of the thick midribs (cushion). Fungal DNA analyses showed that 92 % (48/52) of Angiopteris and 92 % (35/38) of Osmunda have sequences of arbuscular mycorrhizal fungi, which were highly divergent but all belonged to Glomus group A. These results suggest that A. lygodiifolia and O. japonica gametophytes consistently form arbuscular mycorrhizae. Mycorrhizal formation in wild fern gametophytes, based on large-scale sampling with molecular identification of host plant species, was demonstrated for the first time.

  14. Internal transcribed spacer primers and sequences for improved characterization of basidiomycetous orchid mycorrhizas.

    Science.gov (United States)

    Taylor, D Lee; McCormick, Melissa K

    2008-01-01

    Despite advances owing to molecular approaches, several hurdles still obstruct the identification of fungi forming orchid mycorrhizas. The Tulasnellaceae exhibit accelerated evolution of the nuclear ribosomal operon, causing most standard primers to fail in polymerase chain reaction (PCR) trials. Insufficient sequences are available from well characterized isolates and fruitbodies. Lastly, taxon-specific PCR primers are needed in order to explore the ecology of the fungi outside of the orchid root. Here, progress in overcoming these hurdles is reported. Broad-spectrum basidiomycete internal transcribed spacer (ITS) primers that do not exclude most known Tulasnellaceae are presented. blast searches and empirical PCR tests support their wide utility within the Basidiomycota. Taxon-specific ITS primers are presented targeted to orchid-associated Tulasnella, and a core component of the Thelephora-Tomentella complex. The efficiency and selectivity of these primer sets are again supported by blast searches and empirical tests. Lastly, ITS DNA sequences are presented from several strains of Epulorhiza, Ceratorhiza, Ceratobasidium, Sistotrema, Thanatephorus and Tulasnella that were originally described in the landmark mycorrhizal studies of Currah and Warcup. Detailed phylogenetic analyses reveal some inconsistencies in species concepts in these taxonomically challenging resupinate basidiomycetes, but also help to place several sequences from environmental samples.

  15. Identity and specificity of the fungi forming mycorrhizas with the rare mycoheterotrophic orchid Rhizanthella gardneri.

    Science.gov (United States)

    Bougoure, Jeremy; Ludwig, Martha; Brundrett, Mark; Grierson, Pauline

    2009-10-01

    Fully subterranean Rhizanthella gardneri (Orchidaceae) is obligately mycoheterotrophic meaning it is nutritionally dependent on the fungus it forms mycorrhizas with. Furthermore, R. gardneri purportedly participates in a nutrient sharing tripartite relationship where its mycorrhizal fungus simultaneously forms ectomycorrhizas with species of Melaleuca uncinata s.l. Although the mycorrhizal fungus of R. gardneri has been morphologically identified as Thanatephorus gardneri (from a single isolate), this identification has been recently questioned. We sought to clarify the identification of the mycorrhizal fungus of R. gardneri, using molecular methods, and to identify how specific its mycorrhizal relationship is. Fungal isolates taken from all sites where R. gardneri is known to occur shared almost identical ribosomal DNA (rDNA) sequences. The fungal isolate rDNA most closely matched that of other Ceratobasidiales species, particularly within the Ceratobasidium genus. However, interpretation of results was difficult as we found two distinct ITS sequences within all mycorrhizal fungal isolates of R. gardneri that we assessed. All mycorrhizal fungal isolates of R. gardneri readily formed ectomycorrhizas with a range of M. uncinata s.l. species. Consequently, it is likely that R. gardneri can form a nutrient sharing tripartite relationship where R. gardneri is connected to autotrophic M. uncinata s.l. by a common mycorrhizal fungus. These findings have implications for better understanding R. gardneri distribution, evolution and the ecological significance of its mycorrhizal fungus, particularly in relation to nutrient acquisition.

  16. [Effects of nitrogen and carbon addition and arbuscular mycorrhiza on alien invasive plant Ambrosia artemisiifolia].

    Science.gov (United States)

    Huang, Dong; Sang, Wei-guo; Zhu, Li; Song, Ying-ying; Wang, Jin-ping

    2010-12-01

    A greenhouse control experiment was conducted to explore the effects of nitrogen and carbon addition and arbuscular mycorrhiza (AM) on the growth of alien invasive plant Ambrosia artemisiifolia (common ragweed). Nitrogen addition had no significant effects on the morphological indices, biomass and its allocation, and absolute growth rate of A. artemisiifolia, but increased the nitrogen content in the aboveground and underground parts of the plant significantly. Carbon addition increased the content of soil available nitrogen. In this case, the biomass allocation in root system for nutrient (nitrogen) absorption promoted, resulting in a remarkable decrease of branch number, total leaf area, specific leaf area (SLA), and leaf mass ratio. As a result, the total biomass decreased significantly. The symbiosis of A. artemisiifolia and AM fungi had great influence on the common ragweed's soil nitrogen acclimation, which enhanced its resource-capture by the increase of SLA, and this effect was more significant when the soil nitrogen content was low. AM fungi played an important role in the growth of A. artemisiifolia in low-nitrogen environment.

  17. Transcriptome analysis of Glomus mosseae/Medicago sativa mycorrhiza on atrazine stress.

    Science.gov (United States)

    Song, Fuqiang; Li, Jize; Fan, Xiaoxu; Zhang, Quan; Chang, Wei; Yang, Fengshan; Geng, Gui

    2016-02-02

    Arbuscular mycorrhizal fungi (AMF) protect host plants against diverse biotic and abiotic stresses, and promote biodegradation of various contaminants. In this study effect of Glomus mosseae/Medicago sativa mycorrhiza on atrazine degradation was investigated. It was observed that the atrazine degradation rates with any addition level in mycorrhizal treatments were all significantly higher than those in non-mycorrhizal treatments. When atrazine was applied at 20 mg kg(-1), the removal efficiency was up to 74.65%. Therefore, G. mosseae can be considered as ideal inhabitants of technical installations to facilitate phytoremediation. Furthermore, a total of 10.4 Gb was used for de novo transcriptome assembly, resulting in a comprehensive data set for the identification of genes corresponding to atrazine stress in the AM association. After comparative analysis with edgeR, a total of 2,060 differential expressed genes were identified, including 570 up-regulated genes and 1490 down-regulated genes. After excluding 'function unknown' and 'general function predictions only' genes, 172 up-regulated genes were obtained. The differentially expressed genes in AM association with and without atrazine stress were associated with molecular processes/other proteins, zinc finger protein, intracellular/extracellular enzymes, structural proteins, anti-stress/anti-disease protein, electron transport-related protein, and plant growth associated protein. Our results not only prove AMF has important ecological significance on atrazine degradation but also provide evidence for the molecular mechanisms of atrazine degradation by AMF.

  18. Allocation of new growth between shoot, root and mycorrhiza in relation to carbon, nitrogen and phosphate supply: teleonomy with maximum growth rate.

    Science.gov (United States)

    Thornley, John H M; Parsons, Anthony J

    2014-02-07

    Treating resource allocation within plants, and between plants and associated organisms, is essential for plant, crop and ecosystem modelling. However, it is still an unresolved issue. It is also important to consider quantitatively when it is efficient and to what extent a plant can invest profitably in a mycorrhizal association. A teleonomic model is used to address these issues. A six state-variable model giving exponential growth is constructed. This represents carbon (C), nitrogen (N) and phosphorus (P) substrates with structure in shoot, root and mycorrhiza. The shoot is responsible for uptake of substrate C, the root for substrates N and P, and the mycorrhiza also for substrates N and P. A teleonomic goal, maximizing proportional growth rate, is solved analytically for the allocation fractions. Expressions allocating new dry matter to shoot, root and mycorrhiza are derived which maximize growth rate. These demonstrate several key intuitive phenomena concerning resource sharing between plant components and associated mycorrhizae. For instance, if root uptake rate for phosphorus is equal to that achievable by mycorrhiza and without detriment to root uptake rate for nitrogen, then this gives a faster growing mycorrhizal-free plant. However, if root phosphorus uptake is below that achievable by mycorrhiza, then a mycorrhizal association may be a preferred strategy. The approach offers a methodology for introducing resource sharing between species into ecosystem models. Applying teleonomy may provide a valuable short-term means of modelling allocation, avoiding the circularity of empirical models, and circumventing the complexities and uncertainties inherent in mechanistic approaches. However it is subjective and brings certain irreducible difficulties with it. Crown Copyright © 2013 Published by Elsevier Ltd All rights reserved.

  19. [Regulatory genes of garden pea (Pisum sativum L.) controlling the development of nitrogen-fixing nodules and arbuscular mycorrhiza: a review of basic and applied aspects].

    Science.gov (United States)

    Borisov, A Iu; Vasil'chikov, A G; Voroshilova, V A; Danilova, T N; Zhernakov, A I; Zhukov, V A; Koroleva, T A; Kuznetsova, E V; Madsen, L; Mofett, M; Naumkina, T S; Nemankin, T A; Ovchinnikova, E S; Pavlova, Z B; Petrova, N E; Pinaev, A G; Radutoiu, S; Rozov, S M; Rychagova, T S; Solovov, I I; Stougaard, J; Topunov, A F; Weeden, N F; Tsyganov, V E; Shtark, O Iu; Tikhonovich, I A

    2007-01-01

    The review sums up the long experience of the authors and other researchers in studying the genetic system of garden pea (Pisum sativum L.), which controls sthe development of nitrogen-fixing symbiosis and arbuscular mycorrhiza. A justified phenotypic classification of pea mutants is presented. Progress in identifying and cloning symbiotic genes is adequately reflected. The feasibility of using double inoculation as a means of increasing the plant productivity is demonstrated, in which the potential of a tripartite symbiotic system (pea plants-root nodule bacteria-arbuscular mycorrhiza) is mobilized.

  20. Atmospheric CO(2) and mycorrhiza effects on biomass allocation and nutrient uptake of nodulated pea (Pisum sativum L.) plants.

    Science.gov (United States)

    Gavito, M E; Curtis, P S; Mikkelsen, T N; Jakobsen, I

    2000-11-01

    The effect of ambient and elevated atmospheric CO(2) on biomass partitioning and nutrient uptake of mycorrhizal and non-mycorrhizal pea plants grown in pots in a controlled environment was studied. The hypothesis tested was that mycorrhizae would increase C assimilation by increasing photosynthetic rates and reduce below-ground biomass allocation by improving nutrient uptake. This effect was expected to be more pronounced at elevated CO(2) where plant C supply and nutrient demand would be increased. The results showed that mycorrhizae did not interact with atmospheric CO(2) concentration in the variables measured. Mycorrhizae did not affect photosynthetic rates, had no effect on root weight or root length density and almost no effect on nutrient uptake, but still significantly increased shoot weight and reduced root/shoot ratio at harvest. Elevated CO(2) increased photosynthetic rates with no evidence for down-regulation, increased shoot weight and nutrient uptake, had no effect on root weight, and actually reduced root/shoot ratio at harvest. Non-mycorrhizal plants growing at both CO(2) concentrations had lower shoot weight than mycorrhizal plants with similar nutritional status and photosynthetic rates. It is suggested that the positive effect of mycorrhizal inoculation was caused by an enhanced C supply and C use in mycorrhizal plants than in non-mycorrhizal plants. The results indicate that plant growth was not limited by mineral nutrients, but partially source and sink limited for carbon. Mycorrhizal inoculation and elevated CO(2) might have removed such limitations and their effects on above-ground biomass were independent, positive and additive.

  1. A tandem Kunitz protease inhibitor (KPI106)-serine carboxypeptidase (SCP1) controls mycorrhiza establishment and arbuscule development in Medicago truncatula.

    Science.gov (United States)

    Rech, Stefanie S; Heidt, Sven; Requena, Natalia

    2013-09-01

    Plant proteases and protease inhibitors are involved in plant developmental processes including those involving interactions with microbes. Here we show that a tandem between a Kunitz protease inhibitor (KPI106) and a serine carboxypeptidase (SCP1) controls arbuscular mycorrhiza development in the root cortex of Medicago truncatula. Both proteins are only induced during mycorrhiza formation and belong to large families whose members are also mycorrhiza-specific. Furthermore, the interaction between KPI106 and SCP1 analysed using the yeast two-hybrid system is specific, indicating that each family member might have a defined counterpart. In silico docking analysis predicted a putative P1 residue in KPI106 (Lys173) that fits into the catalytic pocket of SCP1, suggesting that KPI106 might inhibit the enzyme activity by mimicking the protease substrate. In vitro mutagenesis of the Lys173 showed that this residue is important in determining the strength and specificity of the interaction. The RNA interference (RNAi) inactivation of the serine carboxypeptidase SCP1 produces aberrant mycorrhizal development with an increased number of septated hyphae and degenerate arbuscules, a phenotype also observed when overexpressing KPI106. Protease and inhibitor are both secreted as observed when expressed in Nicotiana benthamiana epidermal cells. Taken together we envisage a model in which the protease SCP1 is secreted in the apoplast where it produces a peptide signal critical for proper fungal development within the root. KPI106 also at the apoplast would modulate the spatial and/or temporal activity of SCP1 by competing with the protease substrate. © 2013 The Authors The Plant Journal © 2013 John Wiley & Sons Ltd.

  2. Alleviation of drought stress by mycorrhizas is related to increased root H2O2 efflux in trifoliate orange

    OpenAIRE

    Yong-Ming Huang; Ying-Ning Zou; Qiang-Sheng Wu

    2017-01-01

    The Non-invasive Micro-test Technique (NMT) is used to measure dynamic changes of specific ions/molecules non-invasively, but information about hydrogen peroxide (H2O2) fluxes in different classes of roots by mycorrhiza is scarce in terms of NMT. Effects of Funneliformis mosseae on plant growth, H2O2, superoxide radical (O2 ??), malondialdehyde (MDA) concentrations, and H2O2 fluxes in the taproot (TR) and lateral roots (LRs) of trifoliate orange seedlings under well-watered (WW) and drought s...

  3. The use of mycorrhiza and Rhizobium in the growth of three months saga seedling (Adenanthera pavonina

    Directory of Open Access Journals (Sweden)

    Rina Kurniaty

    2017-03-01

    Full Text Available Abstrak. Kurniaty R. 2016. The use of mycorrhiza and Rhizobium in the growth of three months saga seedling (Adenanthera pavonina. Pros Sem Nas Masy Biodiv Indon 2: 6-9. Plants saga tree (Adenanthera pavonina having benefits versatile because almost all parts of crop can be used so that economically valuable high. Wood saga can be used as building material and furniture . Seeds saga have the potential who has a promising as renewable energy source of them because the seeds his containing 14-28% fatty oil who could be classified as non food . In addition oil derived from the seeds of the saga is also very good to treat a disease in, scurvy, injuries, making candles, batik industry, and materials making soap. Research aims to understand the influence of the use of mycorrhizal and Rhizobium in growth seedlings saga age 3 months. Inoculating Rhizobium liquid as many as 1 mL by means of injecting on roots and plants surrounding the hole . The provision of mycorrhizal done by entering 2 g mycorrhizal (Glomus sp into a hole plant at the same time as Rhizobium. Design used is a random factorials consisting of two factors treatment. The first is Rhizobium (A namely: A1 = control and A2= Rhizobium sp. The second factor is mycorrhizal (B consisting of two the standard: B1 = control and B2 = Glomus sp (2 g/ polybag. The results showed that the treatment A2B2 (Rhizobium + mycorrhizal put a value colonization roots highest namely 68,88% with live percent 99,26%, height 10,08 cm, diameter 1.67mm, biomass 0,56 g, TR ratio 2.01 and IMB 0,06 . Nutrient absorption, treatment A2B2 is the nutrient in N 60,30% compared to control, the nutrient P 66,66% compared to control and the nutrient K 123,17% compared to control.

  4. The nitrogen availability interferes with mycorrhiza-induced resistance against Botrytis cinerea in tomato

    Directory of Open Access Journals (Sweden)

    Paloma Sanchez-Bel

    2016-10-01

    Full Text Available Mycorrhizal plants are generally quite efficient in coping with environmental challenges. It has been shown that the symbiosis with arbuscular mycorrhizal fungi (AMF can confer resistance against root and foliar pathogens, although the molecular mechanisms underlying such mycorrhiza-induced resistance (MIR are poorly understood. Tomato plants colonized with the AMF Rhizophagus irregularis display enhanced resistance against the necrotrophic foliar pathogen Botrytis cinerea. Leaves from arbuscular mycorrhizal (AM plants develop smaller necrotic lesions, mirrored also by a reduced levels of fungal biomass. A plethora of metabolic changes takes place in AMF colonized plants upon infection. Certain changes located in the oxylipin pathway indicate that several intermediaries are over-accumulated in the AM upon infection. AM plants react by accumulating higher levels of the vitamins folic acid and riboflavin, indolic derivatives and phenolic compounds such as ferulic acid and chlorogenic acid. Transcriptional analysis support the key role played by the LOX pathway in the shoots associated with MIR against B. cinerea.Interestingly, plants that have suffered a short period of nitrogen starvation appear to react by reprogramming their metabolic and genetic responses by prioritizing abiotic stress tolerance. Consequently, plants subjected to a transient nitrogen depletion become more susceptible to B. cinerea. Under these experimental conditions, MIR is severely affected although still functional. Many metabolic and transcriptional responses which are accumulated or activated by MIR such NRT2 transcript induction and OPDA and most Trp and indolic derivatives accumulation during MIR were repressed or reduced when tomato plants were depleted of N for 48 h prior infection. These results highlight the beneficial roles of AMF in crop protection by promoting induced resistance not only under optimal nutritional conditions but also buffering the susceptibility

  5. Mycorrhizas in the Central European flora: relationships with plant life history traits and ecology.

    Science.gov (United States)

    Hempel, Stefan; Götzenberger, Lars; Kühn, Ingolf; Michalski, Stefan G; Rillig, Matthias C; Zobel, Martin; Moora, Mari

    2013-06-01

    Plant traits have been widely used to characterize different aspects of the ecology of plant species. Despite its wide distribution and its proven significance at the level of individuals, communities, and populations, the ability to form mycorrhizal associations has been largely neglected in these studies so far. Analyzing plant traits associated with the occurrence of mycorrhizas in plants can therefore enhance our understanding of plant strategies and distributions. Using a comparative approach, we tested for associations between mycorrhizal status and habitat characteristics, life history traits, and plant distribution patterns in 1752 species of the German flora (a major part of the Central European flora). Data were analyzed using log-linear models or generalized linear models, both accounting for phylogenetic relationships. Obligatorily mycorrhizal (OM) species tended to be positively associated with higher temperature, drier habitats, and higher pH; and negatively associated with moist, acidic, and fertile soils. Competitive species were more frequently OM, and stress tolerators were non-mycorrhizal (NM), while ruderal species did not show any preference. Facultatively mycorrhizal (FM) species showed the widest geographic and ecological amplitude. Indigenous species were more frequently FM and neophytes (recent aliens) more frequently OM than expected. FM species differed markedly from OM and NM species in almost all analyzed traits. Specifically, they showed a wider geographic distribution and ecological niche. Our study of the relationships between mycorrhizal status and other plant traits provides a comprehensive test of existing hypotheses and reveals novel patterns. The clear distinction between FM and OM + NM species in terms of their ecology opens up a new field of research in plant-mycorrhizal ecology.

  6. Impacts of manganese mining activity on the environment: interactions among soil, plants, and arbuscular mycorrhiza.

    Science.gov (United States)

    Rivera-Becerril, Facundo; Juárez-Vázquez, Lucía V; Hernández-Cervantes, Saúl C; Acevedo-Sandoval, Otilio A; Vela-Correa, Gilberto; Cruz-Chávez, Enrique; Moreno-Espíndola, Iván P; Esquivel-Herrera, Alfonso; de León-González, Fernando

    2013-02-01

    The mining district of Molango in the Hidalgo State, Mexico, possesses one of the largest deposits of manganese (Mn) ore in the world. This research assessed the impacts of Mn mining activity on the environment, particularly the interactions among soil, plants, and arbuscular mycorrhiza (AM) at a location under the influence of an open Mn mine. Soils and plants from three sites (soil under maize, soil under native vegetation, and mine wastes with some vegetation) were analyzed. Available Mn in both soil types and mine wastes did not reach toxic levels. Samples of the two soil types were similar regarding physical, chemical, and biological properties; mine wastes were characterized by poor physical structure, nutrient deficiencies, and a decreased number of arbuscular mycorrhizal fungi (AMF) spores. Tissues of six plant species accumulated Mn at normal levels. AM was absent in the five plant species (Ambrosia psilostachya, Chenopodium ambrosoides, Cynodon dactylon, Polygonum hydropiperoides, and Wigandia urens) established in mine wastes, which was consistent with the significantly lower number of AMF spores compared with both soil types. A. psilostachya (native vegetation) and Zea mays showed mycorrhizal colonization in their root systems; in the former, AM significantly decreased Mn uptake. The following was concluded: (1) soils, mine wastes, and plant tissues did not accumulate Mn at toxic levels; (2) despite its poor physical structure and nutrient deficiencies, the mine waste site was colonized by at least five plant species; (3) plants growing in both soil types interacted with AMF; and (4) mycorrhizal colonization of A. psilostachya influenced low uptake of Mn by plant tissues.

  7. Functional compatibility in cucumber mycorrhizas in terms of plant growth performance and foliar nutrient composition.

    Science.gov (United States)

    Ravnskov, S; Larsen, J

    2016-09-01

    Functional compatibility in cucumber mycorrhizas in terms of plant and fungal growth, and foliar nutrient composition from all possible combinations of six cucumber varieties and three species of arbuscular mycorrhizal (AM) fungi was evaluated. Measurements of foliar nutrient composition included N, P, K, Mg, Ca, Na, Fe, Zn, Mn and Cu. Growth of AM fungi was measured in terms of root colonisation, as examined with microscopy and the AM fungus biomarker fatty acid 16:1ω5 from both phospholipids and neutral lipids. Different responses of plant growth and foliar nutrient profiles were observed for the different AM symbioses examined. The AM fungus Claroideoglomus claroideum caused growth depression in association with four out of six cucumber varieties; Rhizophagus irregularis caused growth promotion in one of six cucumber varieties; whereas Funneliformis mosseae had no effect on the growth performance of any of the cucumber varieties examined. All three AM fungi markedly altered host plant shoot nutrient composition, with the strongest contrast observed between cucumber-R. irregularis symbioses and non-mycorrhizal cucumber plants, independent of cucumber variety. On the other hand, AM fungal growth in roots differed between the three AM fungi, but was unaffected by host genotype. Strong build-up of storage lipids was observed for R. irregularis, which was more moderate in the two other AM fungi. In conclusion, strong differential responses of cucumber varieties to inoculation with different AM fungi in terms of growth and shoot nutrient composition revealed high functional diversity in AM symbioses in cucumber plants. © 2016 German Botanical Society and The Royal Botanical Society of the Netherlands.

  8. Monotropa uniflora plants of eastern Massachusetts form mycorrhizae with a diversity of russulacean fungi.

    Science.gov (United States)

    Yang, S; Pfister, D H

    2006-01-01

    Plant species in the subfamily Monotropoideae are mycoheterotrophs; they obtain fixed carbon from photosynthetic plants via a shared mycorrhizal network. Previous findings show mycoheterotrophic plants exhibit a high level of specificity to their mycorrhizal fungi. In this study we explore the association of mycorrhizal fungi and Monotropa uniflora (Monotropoideae: Ericaceae) in eastern North America. We collected M. uniflora roots and nearby basidiomycete sporocarps from four sites within a 100 km2 area in eastern Massachusetts. We analyzed DNA sequences of the internal transcribed spacer region (ITS) from the fungal nuclear ribosomal gene to assess the genetic diversity of fungi associating with M. uniflora roots. In this analysis we included 20 ITS sequences from Russula sporocarps collected nearby, 44 sequences of Russula or Lactarius species from GenBank and 12 GenBank sequences of fungi isolated from M. uniflora roots in previous studies. We found that all 56 sampled M. uniflora mycorrhizal fungi were members of the Russulaceae, confirming previous research. The analysis showed that most of the diversity of mycorrhizal fungi spreads across the genus Russula. ITS sequences of the mycorrhizal fungi consisted of 20 different phylotypes: 18 of the genus Russula and two of Lactarius, based on GenBank searches. Of the sampled plants, 57% associated with only three of the 20 mycorrhizal fungi detected in roots, and of the 25 sporocarp phylotypes collected three, were associated with M. uniflora. Furthermore the results indicate that the number of different fungal phylotypes associating with M. uniflora of eastern North America is higher than that of western North America but patterns of fungal species abundance might be similar between mycorrhizae from the two locations.

  9. [Effects of Arbuscular Mycorrhizae on growth and essential oil of Atractylodes lancea].

    Science.gov (United States)

    Guo, Lan-Ping; Wang, Hong-Gang; Huang, Lu-Qi; Jiang, You-Xu; Zhu, Yong-Guan; Kong, Wei-Dong; Chen, Bao-Dong; Chen, Mei-Lan; Lin, Shu-Fang; Fang, Zhi-Guo

    2006-09-01

    To study the effects of Arbuscular Mycorrhizae on cultivated Atractylodes lancea. Pot experiment of A. lancea, with (code as AM) or without (code as CK) Glomus mosseae (GM) was conducted 5 times respectively, then the biomass, essential oil, and soil nutrition, soil organism, soil microbial were detected after A. lancea were harvested. (1) Mycorrhizal dependency of A. lancea was 245%, and height of individuals, numbers of leaves, leaf area, biomass of A. lancea were all higher in AM than in CK (P < 0.05). (2) GC-MS analysis with cluster analysis and principal components analysis showed that there were no differences in essential oil of A. lancea between AM and CK. (T3) Total N, available N, available P and available K in AM soil were all lower than in CK soil. (4) GC-MS analysis showed organic matters changed differenly in AM soil and CK soil, components 5,6 in AM soil were higher than that in CK soil, but component 9, 10, 11 were lower in AM soil than that in CK soil. (5) Biolog detect showed AWCD of AM soil microbe were higher than that of CK soil throughout the incubation, and AWCD of the former was 0.66, and the later was 0.46 after 192 h incubation. and t-test showed, Shannon seven indices and McIntosh'seven indices were same both at 72 h and 192 h, and diversity indices of Shannon and McIntosh were also same at 72 h, but AM soil microbe were higher than CK soil microbe at 168 h (P < 0.05). AM could promote nutrition uptake, improve the function diversity and activity of microbe in rhizosphere of A. lancea, influence the composition of the organic matter, that lead the growth of A. lancea, but not to the quality.

  10. Can corn plants inoculated with arbuscular mycorrhiza fungi affect soil clay assemblage?

    Science.gov (United States)

    Adamo, P.; Cozzolino, V.; Di Meo, V.; Velde, B.

    2012-04-01

    Plants can extract K from exchangeable and non-exchangeable sites in the soil clay mineral structures. The latter, known as fixed K, is usually seen as an illite layer, i.e. an anhydrous K layer that forms a 1.0 nm structural layer unit as seen by X-ray diffraction. Nutrient availability can be enhanced in the root zone by arbuscular mycorrhiza fungi. In this study, the effects of non-inoculated and Glomus intraradices inoculated corn plant growth under different experimental conditions on soil K-bearing clay minerals were identified. The soil, a Vertic Xerofluvent, was planted in corn in a 2008-2010 randomized field experiment. Bulk and rhizosphere soil sampling was carried out from May to September 2010 from fertilized plots (N200P90K160 and N200P0K160) with and without plants. According to XRD analysis, three major K-bearing minerals were present in soil: smectite-rich mixed layer mineral, illite-rich mixed layer mineral and illite. Results at 40DAS indicate extraction of K from clay minerals by plant uptake, whereas at 130DAS much of the nutrient seems to be returned to the soil. There is an apparent difference between bulk and rhizophere clays. The XRD patterns are not unequivocally affected by Glomus inoculation. There are observable changes in clay mineralogy in fallow unfertilized compared with fertilized soil. In the studied soil, the illite rich mixed-layer minerals seem to be the source of K absorbed by plants, while illite acts as sink of K released from the plant-microorganisms system at the end of the growing season and as source for the following crop.

  11. [Effect of Arbuscular Mycorrhiza (AM) on Tolerance of Cattail to Cd Stress in Aquatic Environment].

    Science.gov (United States)

    Luo, Peng-cheng; Li, Hang; Wang, Shu-guang

    2016-02-15

    Hygrophytes are planted more and more in landscaping and greening in many cities, but they often encounter threat from environmental pollution. Arbuscular mycorrhiza ( AM ) have been confirmed to enhance the tolerance of terrestrial plants to environmental pollution in many previous studies, but it is unclear how they affect hygrophytes. In the present study, a hydroponic culture experiment was carried out to investigate the effects of AM fungi (Glomus etunicatum) inoculation on the tolerance of cattail (Typha latifolia) to different concentrations Cd2+ (0, 2.5, 5.0 mg x L(-1)). The aim was to provide reference for evaluating whether mycorrhizal technology can be used to enhance the tolerance of hygrophytes to environmental pollution. The results showed that symbiotic association was well established between AM fungi and cattail roots, and the mycorrhizal colonization rates (MCR) were beyond 30%. However, MCR presented downward trend one month after mycorrhizal cattails were transported to solution, and the maximal decrease was 25.5% (P < 0.05). AM increased pigment concentrations and peroxidase (POD) activity in cattail leaves, and also increased roots radial oxygen loss. However, AM only produced significant effect on increase of fresh weight in 5 mg x L(-1) Cd2+ solution. Although plant growth was inhibited by 5 mg x L(-1) Cd2+ and MCR was lower, AM increased Cd uptake of cattail at the two Cd2+ levels, and the maximal increments were 40.24% and 56.52% in aboveground and underground parts, respectively. This study indicates that AM has potential to enhance the tolerance of hygrophytes to environmental pollution and might be used to remedy heavy metal pollution.

  12. Nutrient limitation drives response of Calamagrostis epigejos to arbuscular mycorrhiza in primary succession.

    Science.gov (United States)

    Rydlová, Jana; Püschel, David; Dostálová, Magdalena; Janoušková, Martina; Frouz, Jan

    2016-10-01

    Little is known about the functioning of arbuscular mycorrhizal (AM) symbiosis over the course of primary succession, where soil, host plants, and AM fungal communities all undergo significant changes. Over the course of succession at the studied post-mining site, plant cover changes from an herbaceous community to the closed canopy of a deciduous forest. Calamagrostis epigejos (Poaceae) is a common denominator at all stages, and it dominates among AM host species. Its growth response to AM fungi was studied at four distinctive stages of natural succession: 12, 20, 30, and 50 years of age, each represented by three spatially separated sites. Soils obtained from all 12 studied sites were γ-sterilized and used in a greenhouse experiment in which C. epigejos plants were (1) inoculated with a respective community of native AM fungi, (2) inoculated with reference AM fungal isolates from laboratory collection, or (3) cultivated without AM fungi. AM fungi strongly boosted plant growth during the first two stages but not during the latter two, where the effect was neutral or even negative. While plant phosphorus (P) uptake was generally increased by AM fungi, no contribution of mycorrhizae to nitrogen (N) uptake was recorded. Based on N:P in plant biomass, we related the turn from a positive to a neutral/negative effect of AM fungi on plant growth, observed along the chronosequence, to a shift in relative P and N availability. No functional differences were found between native and reference inocula, yet root colonization by the native AM fungi decreased relative to the reference inoculum in the later succession stages, thereby indicating shifts in the composition of AM fungal communities reflected in different functional characteristics of their members.

  13. Arbuscular mycorrhiza formation and its function under elevated atmospheric O3: A meta-analysis.

    Science.gov (United States)

    Wang, Shuguang; Augé, Robert M; Toler, Heather D

    2017-07-01

    We quantitatively evaluated the effects of elevated O3 on arbuscular mycorrhiza (AM) formation and on AM role in promoting plant growth in regard to several moderating variables (O3 levels, O3 exposure duration, plant types, AM fungi family, and additional stress) by means of meta-analysis of published data. The analysis consisted of 117 trials representing 20 peer-reviewed articles and 16 unpublished trials. Relative to non-mycorrhizal controls, AM inoculation did not significantly alter plant growth (shoot biomass, root biomass, total biomass and plant height) when O3 concentration was less than 80 ppb, but at concentrations above 80 ppb symbiosis was associated with increases of 68% in shoot biomass and 131% in root biomass. AM effects on plant growth were affected by the duration of O3 exposure but did not differ much with AM fungi taxa or plant type. AM symbiosis has also led to higher yields under O3 stress, relative to the non-mycorrhizal plants, and the AM effects have been more pronounced as O3 concentration increases. As with biomass, AM effects on yield have been affected by the duration of O3 exposure, with the greatest increase (100%) occurring at 61-90 d. AM-induced promotion of yield differed with fungal species but not with plant type or other abiotic stress. Colonization of roots by AM fungi has been negatively affected by elevated O3 compared to ambient O3; total mycorrhizal colonization rate (MCR), arbuscular MCR, vesicular MCR and hyphal coil MCR declined as O3 levels rose. AM colonization rates were affected by duration of O3 exposure, plant type, AM fungal taxa and other concurrent stresses in most cases. The analysis showed that AM inoculation has the potential to ameliorate detrimental effects of elevated O3 on plant growth and productivity, despite colonization rates being negatively affected by elevated O3. Copyright © 2017. Published by Elsevier Ltd.

  14. (VAM) and phosphate solubilizing bacteria (PSB)

    African Journals Online (AJOL)

    User

    2013-09-18

    Sep 18, 2013 ... The leaves are used for snake bites and to cure boils and abscesses as it has potent ..... Biologia Plantarum. 44(2): 277-281. Senthilkumar PK, Sivagurunathan P (2012). Comparative effect on bacterial biofertilizers on growth and yield of green gram (Phaseolus radiata L.) and cow pea (Vigna siensis Edhl.) ...

  15. Eto vam ne Dzheims Bond / Vincent Vega

    Index Scriptorium Estoniae

    Vega, Vincent

    2000-01-01

    Actionfilmi "Võimatu missioon" ("Mission : Impossible") järg "Võimatu Missioon 2 ("Mission : Impossible II") : režissöör John Woo : peaosaline ja produtsent Tom Cruise : Ameerika Ühendriigid 2000

  16. Expression profiles of defence related cDNAs in oil palm (Elaeis guineensis Jacq.) inoculated with mycorrhizae and Trichoderma harzianum Rifai T32.

    Science.gov (United States)

    Tan, Yung-Chie; Wong, Mui-Yun; Ho, Chai-Ling

    2015-11-01

    Basal stem rot is one of the major diseases of oil palm (Elaies guineensis Jacq.) caused by pathogenic Ganoderma species. Trichoderma and mycorrhizae were proposed to be able to reduce the disease severity. However, their roles in improving oil palm defence system by possibly inducing defence-related genes in the host are not well characterized. To better understand that, transcript profiles of eleven putative defence-related cDNAs in the roots of oil palm inoculated with Trichoderma harzianum T32 and mycorrhizae at different time points were studied. Transcripts encoding putative Bowman-Birk protease inhibitor (EgBBI2) and defensin (EgDFS) increased more than 2 fold in mycorrhizae-treated roots at 6 weeks post inoculation (wpi) compared to those in controls. Transcripts encoding putative dehydrin (EgDHN), glycine-rich RNA binding protein (EgGRRBP), isoflavone reductase (EgIFR), type 2 ribosome inactivating protein (EgT2RIP), and EgDFS increased in the oil palm roots treated with T. harzianum at 6 and/or 12 wpi compared to those in the controls. Some of these genes were also expressed in oil palm roots treated with Ganoderma boninense. This study provides an insight of some defence-related genes induced by Trichoderma and mycorrhizae, and their roles as potential agents to boost the plant defence system. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  17. Effects of Tissue Culture and Mycorrhiza Applications in Organic Farming on Concentrations of Phytochemicals and Antioxidant Capacities in Ginger (Zingiber officinale Roscoe) Rhizomes and Leaves.

    Science.gov (United States)

    Min, Byungrok R; Marsh, Lurline E; Brathwaite, Keegan; Daramola, Adebola O

    2017-04-01

    Tissue culture and mycorrhiza applications can provide disease-free seedlings and enhanced nutrient absorption, respectively, for organic farming. Ginger (Zingiber officinale Roscoe) is rich in phytochemicals and has various health-protective potentials. This study was aimed at determining effects of tissue culture and mycorrhiza applications alone or in combinations in organic farming on phytochemical contents (total phenolics and flavonoids [TP and TF, respectively], gingerol and shogaol homologues, phenolic acids, and carotenoids) and antioxidant capacities (DPPH [2,2-diphenyl-1-picrylhydrazyl] radical scavenging, oxygen radical absorbance (ORAC), and iron-chelating capacities [ICC]) in solvent-extractable (Free) and cell-wall-matrix-bound (Bound) fractions of ginger rhizome and Free fraction of the leaves in comparison with non-organics. Concentrations of the phytochemicals and antioxidant capacities, except for carotenoids and ICC, were significantly higher in organic ginger rhizomes and leaves than in non-organics regardless of the fractions and treatments (P culture and mycorrhiza significantly increased concentrations of TF and gingerols and ORAC in the Free fraction of the rhizome (P Bound fractions of the rhizomes. Six-gingerol, ferulic acid, and lutein were predominant ones among gingerols, phenolic acids, and carotenoids, respectively, in ginger rhizomes. The results suggest that organic farming with mycorrhiza and tissue culture applications can increase concentrations of phytochemicals and antioxidant capacities in ginger rhizomes and leaves and therefore improve their health-protective potentials. © 2017 Institute of Food Technologists®.

  18. A comparison of the development and metabolic activity of mycorrhizas formed by arbuscular mycorrhizal fungi from different genera on two tropical forage legumes

    NARCIS (Netherlands)

    Boddington, C.L.; Dodd, J.C.

    1998-01-01

    Two glasshouse experiments were done to assess the development and metabolic activity of mycorrhizas formed by isolates of arbuscular mycorrhizal fungi (AMF) from three different genera, Acaulospora, Gigaspora and Glomus on either Pueraria phaseoloides L. or Desmodium ovalifolium L. plants. The

  19. [Regulatory genes of garden pea (Pisum sativum L.) controlling the development of nitrogen-fixing nodules and arbuscular mycorrhiza: a review of basic and applied aspects

    DEFF Research Database (Denmark)

    Borisov, A Iu; Vasil'chikov, A G; Voroshilova, V A

    2007-01-01

    . Progress in identifying and cloning symbiotic genes is adequately reflected. The feasibility of using double inoculation as a means of increasing the plant productivity is demonstrated, in which the potential of a tripartite symbiotic system (pea plants-root nodule bacteria-arbuscular mycorrhiza...

  20. MYCORRHIZAL AND NONMYCORRHIZAL DOUGLAS-FIR GROWN IN HYDROCULTURE - THE EFFECT OF NUTRIENT CONCENTRATION ON THE FORMATION AND FUNCTIONING OF MYCORRHIZA

    NARCIS (Netherlands)

    KAMMINGAVANWIJK, C; PRINS, HBA; KUIPER, PJC

    1992-01-01

    A series of experiments using the Douglas fir as the subject of research were performed in hydroculture. Different relative nutrient addition rates were used prior to and after plants had been inoculated with Laccaria bicolor. The effect of the resulting nutrient conditions on mycorrhiza formation

  1. Alleviation of drought stress by mycorrhizas is related to increased root H2O2 efflux in trifoliate orange.

    Science.gov (United States)

    Huang, Yong-Ming; Zou, Ying-Ning; Wu, Qiang-Sheng

    2017-02-08

    The Non-invasive Micro-test Technique (NMT) is used to measure dynamic changes of specific ions/molecules non-invasively, but information about hydrogen peroxide (H2O2) fluxes in different classes of roots by mycorrhiza is scarce in terms of NMT. Effects of Funneliformis mosseae on plant growth, H2O2, superoxide radical (O2·-), malondialdehyde (MDA) concentrations, and H2O2 fluxes in the taproot (TR) and lateral roots (LRs) of trifoliate orange seedlings under well-watered (WW) and drought stress (DS) conditions were studied. DS strongly inhibited mycorrhizal colonization in the TR and LRs, whereas mycorrhizal inoculation significantly promoted plant growth and biomass production. H2O2, O2·-, and MDA concentrations in leaves and roots were dramatically lower in mycorrhizal seedlings than in non-mycorrhizal seedlings under DS. Compared with non-mycorrhizal seedlings, mycorrhizal seedlings had relatively higher net root H2O2 effluxes in the TR and LRs especially under WW, as well as significantly higher total root H2O2 effluxes in the TR and LRs under WW and DS. Total root H2O2 effluxes were significantly positively correlated with root colonization but negatively with root H2O2 and MDA concentrations. It suggested that mycorrhizas induces more H2O2 effluxes of the TR and LRs, thus, alleviating oxidative damage of DS in the host plant.

  2. Antifungal genes expressed in transgenic pea (Pisum sativum L.) do not affect root colonization of arbuscular mycorrhizae fungi.

    Science.gov (United States)

    Kahlon, Jagroop Gill; Jacobsen, Hans-Jörg; Cahill, James F; Hall, Linda M

    2017-06-12

    Genetically modified crops have raised concerns about unintended consequences on non-target organisms including beneficial soil associates. Pea transformed with four antifungal genes 1-3 β glucanase, endochitinase, polygalacturonase-inhibiting proteins, and stilbene synthase is currently under field-testing for efficacy against fungal diseases in Canada. Transgenes had lower expression in the roots than leaves in greenhouse experiment. To determine the impact of disease-tolerant pea or gene products on colonization by non-target arbuscular mycorrhizae and nodulation by rhizobium, a field trial was established. Transgene insertion, as single gene or stacked genes, did not alter root colonization by arbuscular mycorrhiza fungus (AMF) or root nodulation by rhizobium inoculation in the field. We found no effect of transgenes on the plant growth and performance although, having a dual inoculant with both AMF and rhizobium yielded higher fresh weight shoot-to-root ratio in all the lines tested. This initial risk assessment of transgenic peas expressing antifungal genes showed no deleterious effect on non-target organisms.

  3. Mycorrhiza helper bacterium Streptomyces AcH 505 induces differential gene expression in the ectomycorrhizal fungus Amanita muscaria.

    Science.gov (United States)

    Schrey, Silvia D; Schellhammer, Michael; Ecke, Margret; Hampp, Rüdiger; Tarkka, Mika T

    2005-10-01

    The interaction between the mycorrhiza helper bacteria Streptomyces nov. sp. 505 (AcH 505) and Streptomyces annulatus 1003 (AcH 1003) with fly agaric (Amanita muscaria) and spruce (Picea abies) was investigated. The effects of both bacteria on the mycelial growth of different ectomycorrhizal fungi, on ectomycorrhiza formation, and on fungal gene expression in dual culture with AcH 505 were determined. The fungus specificities of the streptomycetes were similar. Both bacterial species showed the strongest effect on the growth of mycelia at 9 wk of dual culture. The effect of AcH 505 on gene expression of A. muscaria was examined using the suppressive subtractive hybridization approach. The responsive fungal genes included those involved in signalling pathways, metabolism, cell structure, and the cell growth response. These results suggest that AcH 505 and AcH 1003 enhance mycorrhiza formation mainly as a result of promotion of fungal growth, leading to changes in fungal gene expression. Differential A. muscaria transcript accumulation in dual culture may result from a direct response to bacterial substances.

  4. Herbivory and arbuscular mycorrhiza in natural populations of Datura stramonium L.: correlation with the availability of nutrients in the soil

    Directory of Open Access Journals (Sweden)

    Ana Aguilar-Chama

    2016-03-01

    Full Text Available Trophic interactions impose important costs to their host plants, affecting patterns of resource allocation. The relationship between host and consumers is also influenced by the availability of resources, e. g., soil nutrients. In this study, we explored the relationship among mycorrhiza-plant-herbivore in natural populations of Datura stramonium and their correlation with the content of phosphorus, nitrogen and carbon in the soil. We estimated the vegetative and reproductive biomass of plants, the arbuscular mycorrhizal colonization and the level of herbivory in populations of D. stramonium. The local abundance of D. stramonium was negatively related to the content of phosphorus in the soil. In contrast, soil carbon concentration affected positively the vegetative and reproductive mass of D. stramonium, although it was negatively correlated with the specific leaf area (SLA. Of the trophic interactions only herbivory was significantly correlated with the SLA and no relationship was detected between the two interaction types. The lack of significant response of mycorrhizae to the soil nutrients concentration, plant performance, and herbivory may result from the stochasticity in the availability of mycorrhizal inoculum (identity and abundance in the populations studied.

  5. Identification and functional characterization of a sulfate transporter induced by both sulfur starvation and mycorrhiza formation in Lotus japonicus.

    Science.gov (United States)

    Giovannetti, Marco; Tolosano, Matteo; Volpe, Veronica; Kopriva, Stanislav; Bonfante, Paola

    2014-11-01

    Arbuscular mycorrhizas (AMs) are one of the most widespread symbioses in the world. They allow plants to receive mineral nutrients from the symbiotic fungus which in turn gets back up to 20% of plant carbon and completes its life cycle. Especially in low-nutrient conditions, AM fungi are capable of significantly improving plant phosphate and nitrogen acquisition, but fewer data are available about sulfur (S) nutrition. We focused on S metabolism in Lotus japonicus upon mycorrhizal colonization under sulfur starvation or repletion. We investigated both tissue sulfate concentrations and S-related gene expression, at cell-type or whole-organ level. Gene expression and sulfate tissue concentration showed that Rhizophagus irregularis colonization can improve plant S nutritional status under S starvation. A group 1 sulfate transporter, LjSultr1;2, induced by both S starvation and mycorrhiza formation, was identified. Its transcript was localized in arbuscule-containing cells, which was confirmed with a promoter-GUS assay, and its function was verified through phenotyping of TILLING mutants in nonmycorrhizal seedlings. LjSultr1;2 thus appears to encode a key protein involved in plant sulfate uptake. In contrast to phosphate transporters, a single gene, LjSultr1;2, seems to mediate both direct and symbiotic pathways of S uptake in L. japonicus. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  6. The Petunia GRAS Transcription Factor ATA/RAM1 Regulates Symbiotic Gene Expression and Fungal Morphogenesis in Arbuscular Mycorrhiza.

    Science.gov (United States)

    Rich, Mélanie K; Schorderet, Martine; Bapaume, Laure; Falquet, Laurent; Morel, Patrice; Vandenbussche, Michiel; Reinhardt, Didier

    2015-07-01

    Arbuscular mycorrhiza (AM) is a mutual symbiosis that involves a complex symbiotic interface over which nutrients are exchanged between the plant host and the AM fungus. Dozens of genes in the host are required for the establishment and functioning of the interaction, among them nutrient transporters that mediate the uptake of mineral nutrients delivered by the fungal arbuscules. We have isolated in a genetic mutant screen a petunia (Petunia hybrida) Gibberellic Acid Insensitive, Repressor of Gibberellic Acid Insensitive, and Scarecrow (GRAS)-type transcription factor, Atypical Arbuscule (ATA), that acts as the central regulator of AM-related genes and is required for the morphogenesis of arbuscules. Forced mycorrhizal inoculations from neighboring wild-type plants revealed an additional role of ATA in restricting mycorrhizal colonization of the root meristem. The lack of ATA, which represents the ortholog of Required For Arbuscular Mycorrhiza1 in Medicago truncatula, renders the interaction completely ineffective, hence demonstrating the central role of AM-related genes for arbuscule development and function. © 2015 American Society of Plant Biologists. All Rights Reserved.

  7. Arbuscular Mycorrhiza Stimulates Biological Nitrogen Fixation in Two Medicago spp. through Improved Phosphorus Acquisition

    Science.gov (United States)

    Püschel, David; Janoušková, Martina; Voříšková, Alena; Gryndlerová, Hana; Vosátka, Miroslav; Jansa, Jan

    2017-01-01

    Legumes establish root symbioses with rhizobia that provide plants with nitrogen (N) through biological N fixation (BNF), as well as with arbuscular mycorrhizal (AM) fungi that mediate improved plant phosphorus (P) uptake. Such complex relationships complicate our understanding of nutrient acquisition by legumes and how they reward their symbiotic partners with carbon along gradients of environmental conditions. In order to disentangle the interplay between BNF and AM symbioses in two Medicago species (Medicago truncatula and M. sativa) along a P-fertilization gradient, we conducted a pot experiment where the rhizobia-treated plants were either inoculated or not inoculated with AM fungus Rhizophagus irregularis ‘PH5’ and grown in two nutrient-poor substrates subjected to one of three different P-supply levels. Throughout the experiment, all plants were fertilized with 15N-enriched liquid N-fertilizer to allow for assessment of BNF efficiency in terms of the fraction of N in the plants derived from the BNF (%NBNF). We hypothesized (1) higher %NBNF coinciding with higher P supply, and (2) higher %NBNF in mycorrhizal as compared to non-mycorrhizal plants under P deficiency due to mycorrhiza-mediated improvement in P nutrition. We found a strongly positive correlation between total plant P content and %NBNF, clearly documenting the importance of plant P nutrition for BNF efficiency. The AM symbiosis generally improved P uptake by plants and considerably stimulated the efficiency of BNF under low P availability (below 10 mg kg-1 water extractable P). Under high P availability (above 10 mg kg-1 water extractable P), the AM symbiosis brought no further benefits to the plants with respect to P nutrition even as the effects of P availability on N acquisition via BNF were further modulated by the environmental context (plant and substrate combinations). As a response to elevated P availability in the substrate, the extent of root length colonization by AM fungi was

  8. Effets de la double symbiose Rhizobium TAL 1147-Glomus clarum sur la croissance et la nodulation de Racosperma auriculiforme en République Démocratique du Congo

    Directory of Open Access Journals (Sweden)

    Bulakali, B.

    1999-01-01

    Full Text Available Effects of Inoculation with Rhizobium TAL 1147'-Glomus Clarum in a Nursery on Racosperma Auriculiforme Growth and Nodulation in Democratie Republic of Congo. The efficiency evaluation of five vesicular-arbuscular mycorrhiza spp. revealed that the mycobiont Glomus clarum is suitable for the mycorrhizogene replanting of the Kinzono grassy savanna. This present study reports results of effects of its inoculation at the same time that the Rhizobium TAL 1147 in nursery on Racosperma auriculiforme growth and nodulation in this same savanna's soil. Compared to the individual inoculation (Glomus clarum or Rhizobium TAL 1147 and to the uninoculated control, the dual inoculation Rhizobium TAL 1147-Glomus clarum has improved significantly (P <0.01 the growth and the nodulation of this legume tree five months after the sowing. A such inoculation can be recommended for an effective implantation at large-scale of this specie in poor Kinzono soil in nitrogen and in soluble phosphore.

  9. Tree-mycorrhiza symbiosis accelerate mineral weathering: Evidences from nanometer-scale elemental fluxes at the hypha-mineral interface

    Science.gov (United States)

    Bonneville, Steeve; Morgan, Daniel J.; Schmalenberger, Achim; Bray, Andrew; Brown, Andrew; Banwart, Steven A.; Benning, Liane G.

    2011-11-01

    In soils, mycorrhiza (microscopic fungal hypha) living in symbiosis with plant roots are the biological interface by which plants obtain, from rocks and organic matter, the nutrients necessary for their growth and maintenance. Despite their central role in soils, the mechanism and kinetics of mineral alteration by mycorrhiza are poorly constrained quantitatively. Here, we report in situ quantification of weathering rates from a mineral substrate, (0 0 1) basal plane of biotite, by a surface-bound hypha of Paxillus involutus, grown in association with the root system of a Scots pine, Pinus sylvestris. Four thin-sections were extracted by focused ion beam (FIB) milling along a single hypha grown over the biotite surface. Depth-profile of Si, O, K, Mg, Fe and Al concentrations were performed at the hypha-biotite interface by scanning transmission electron microscopy-energy dispersive X-ray spectroscopy (STEM-EDX). Large removals of K (50-65%), Mg (55-75%), Fe (80-85%) and Al (75-85%) were observed in the topmost 40 nm of biotite underneath the hypha while Si and O are preserved throughout the depth-profile. A quantitative model of alteration at the hypha-scale was developed based on solid-state diffusion fluxes of elements into the hypha and the break-down/mineralogical re-arrangement of biotite. A strong acidification was also observed with hypha bound to the biotite surface reaching pH mycorrhiza accelerate the biotite alteration kinetics between pH 3.5 and 5.8 to ˜0.04 μmol biotite m -2 h -1. Our current work reaffirms that fungal mineral alteration is a process that combines our previously documented bio-mechanical forcing with the μm-scale acidification mediated by surface-bound hypha and a subsequent chemical element removal due to the fungal action. As such, our study presents a first kinetic framework for mycorrhizal alteration at the hypha-scale under close-to-natural experimental conditions.

  10. Effect of Mycorrhiza Symbiosis on Yield, Yield Components and Water Use Efficiency of Sesame (Sesamum indicum L. Affected by Different Irrigation Regimes in Mashhad Condition

    Directory of Open Access Journals (Sweden)

    A Koocheki

    2016-02-01

    Full Text Available Introduction Plant association with mycorrhiza has been considered as one of the options to improve input efficiency particularly for water and nutrient - (Allen and Musik, 1993; Bolan, 1991. This has been due to kncreasing the absorbing area of the root and therefore better contact with water and nutrients. Inoculation with mycorrhiza enhances nutrient uptake with low immobility such as phosphorus and solphur-, improve association and could be an option to drought and other environmental abnormalities such as salinity (Rice et al., 2002. Moreover, higher water use efficiency (WUE for crops -has been reported in the literatures (Sekhara and Reddy, 1993.The sustainable use of scarce water resources in Iran is a priority for agricultural development. The pressure of using water in agriculture sector is increasing, so creating ways to improve water-use efficiency and taking a full advantage of available water are crucial. Water stress reduce crop yield by impairing the growth of crop canopy and biomass. Scheduling water application is very crucial for efficient use of drip irrigation system, as excessive irrigation reduces yield, while inadequate irrigation causes water stress and reduces production. The aim of present study was to evaluate the symbiotic effect of mycorrhiza on yield, yield components and water use efficiency of sesame under different irrigation regimes in Mashhad. Material and Methods In order to investigate the impact of inoculation with two species of Arbuscular mycorrhiza fungi on yield, yield components and water use efficiency (WUE of sesame (Sesamum indicum L. under different irrigation regimes, an experiment was conducted as split plot based on a randomized complete block design with three replications during two growing seasons 2009-2010 and 2010-2011 at the Agricultural Research Station, College of Agriculture, Ferdowsi University of Mashhad.. The experimental factors were three irrigation regimes include 2000, 3000 and

  11. The role of flavonoids in the establishment of plant roots endosymbioses with arbuscular mycorrhiza fungi, rhizobia and Frankia bacteria

    Science.gov (United States)

    Abdel-Lateif, Khalid; Bogusz, Didier; Hocher, Valérie

    2012-01-01

    Flavonoids are a group of secondary metabolites derived from the phenylpropanoid pathway. They are ubiquitous in the plant kingdom and have many diverse functions including key roles at different levels of root endosymbioses. While there is a lot of information on the role of particular flavonoids in the Rhizobium-legume symbiosis, yet their exact role during the establishment of arbuscular mycorrhiza and actinorhizal symbioses still remains unclear. Within the context of the latest data suggesting a common symbiotic signaling pathway for both plant-fungal and plant bacterial endosymbioses between legumes and actinorhiza-forming fagales, this mini-review highlights some of the recent studies on the three major types of root endosymbioses. Implication of the molecular knowledge of endosymbioses signaling and genetic manipulation of flavonoid biosynthetic pathway on the development of strategies for the transfer and optimization of nodulation are also discussed. PMID:22580697

  12. Effect of chemophytostabilization practices on arbuscular mycorrhiza colonization of Deschampsia cespitosa ecotype Warynski at different soil depths

    Energy Technology Data Exchange (ETDEWEB)

    Gucwa-Przepiora, E.; Malkowski, E.; Sas-Nowosielska, A.; Kucharski, R.; Krzyzak, J.; Kita, A.; Romkens, P.F.A.M. [University of Silesia, Katowice (Poland)

    2007-12-15

    The effects of chemophytostabilization practices on arbuscular mycorrhiza (AM) of Deschampsia cespitosa roots at different depths in soils highly contaminated with heavy metals were studied in field trials. Mycorrhizal parameters, including frequency of mycorrhization, intensity of root cortex colonization and arbuscule abundance were studied. Correlations between concentration of bioavailable Cd, Zn, Pb and Cu in soil and mycorrhizal parameters were estimated. An increase in AM colonization with increasing soil depth was observed in soils with spontaneously, growing D. cespitosa. A positive effect of chemophytostabilization amendments (calcium phosphate, lignite) on AM colonization was found in the soil layers to which the amendments were applied. Negative correlation coefficients between mycorrhizal parameters and concentration of bioavailable Cd and Zn in soil were obtained. Our results demonstrated that chemophytostabilization practices enhance AM colonization in D. cespitosa roots, even in soils fertilized with high rates of phosphorus.

  13. Role of arbuscular mycorrhiza in alleviating salinity stress in wheat (Triticum aestivum L.) grown under ambient and elevated CO2

    DEFF Research Database (Denmark)

    Zhu, X.; Song, F.; Liu, S.

    2016-01-01

    Plant growth and development are influenced by future elevated atmospheric CO2 concentration and increased salinity stress. AM (arbuscular mycorrhiza) symbiosis has been shown to improve plant growth and resistance to environmental stresses. The aim of this study was to investigate the potential...... role of AM fungus in alleviating salinity stress in wheat (Triticum aestivum L.) plants grown under ambient and elevated CO2 concentrations. Wheat plants inoculated or not inoculated with AM fungus were grown in two glasshouses with different CO2 concentrations (400 and 700 μmol l−1) and salinity...... levels (0, 9.5 and 19.0 dS m−1). Results showed that salinity stress decreased and elevated CO2 increased AM colonization. AM inoculation increased plant dry weight under elevated CO2 and salinity stress. Stomatal conductance, density, size and aperture of AM plants were greater than non-AM plants. AM...

  14. Occurrence of Arbuscular Mycorrhizas and Dark Septate Endophytes in Hydrophytes from Lakes and Streams in Southwest China

    Science.gov (United States)

    Kai, Wang; Zhiwei, Zhao

    2006-02-01

    In this study, the colonization of arbuscular mycorrhizas (AM) and dark septate endophytes (DSE) in 140 specimens of 32 hydrophytes collected from four lakes and four streams in southwest China were investigated. The arbuscular mycorrhizal fungi (AMF) and DSE colonization in these hydrophytes were rare. Typical AM structures were observed in one of the 25 hydrophytic species collected in lakes and six of the 17 species collected in streams.Spores of 10 identified AMF species and an unidentified Acaulospora sp. were isolated from the sediments. The identified AMF came from the four genera, Acaulospora, Gigaspora, Glomus and Scutellospora . Glomus and G. mosseae were the dominant genus and species respectively in these aquatic environments.The presence of DSE in hydrophytes was recorded for the first time. DSE occurred in one of the 25 hydrophyte species collected in lakes and three of the 17 species collected in streams.

  15. The role of flavonoids in the establishment of plant roots endosymbioses with arbuscular mycorrhiza fungi, rhizobia and Frankia bacteria.

    Science.gov (United States)

    Abdel-Lateif, Khalid; Bogusz, Didier; Hocher, Valérie

    2012-06-01

    Flavonoids are a group of secondary metabolites derived from the phenylpropanoid pathway. They are ubiquitous in the plant kingdom and have many diverse functions including key roles at different levels of root endosymbioses. While there is a lot of information on the role of particular flavonoids in the Rhizobium-legume symbiosis, yet their exact role during the establishment of arbuscular mycorrhiza and actinorhizal symbioses still remains unclear. Within the context of the latest data suggesting a common symbiotic signaling pathway for both plant-fungal and plant bacterial endosymbioses between legumes and actinorhiza-forming fagales, this mini-review highlights some of the recent studies on the three major types of root endosymbioses. Implication of the molecular knowledge of endosymbioses signaling and genetic manipulation of flavonoid biosynthetic pathway on the development of strategies for the transfer and optimization of nodulation are also discussed.

  16. Arbuscular mycorrhizae of the palm Astrocaryum mexicanum in disturbed and undisturbed stands of a Mexican tropical forest.

    Science.gov (United States)

    Núñez-Castillo, O; Alvarez-Sánchez, F J

    2003-10-01

    Tropical forests are dynamic systems with extensive natural disturbance, gaps in the canopy being one of the most important types. Tree and branch fall are often the principal cause of natural disturbance. This research was done on adult individuals of a very abundant palm ( Astrocaryum mexicanum Liebm, Arecaceae), which is found in the understorey of the forest at Los Tuxtlas, Mexico. Percentages of colonization by arbuscular mycorrhizae were determined for individuals selected randomly from plots located both in gaps and under closed canopy. The highest percentages of total colonization, as well as those of hyphae and vesicles, were recorded for gaps. In forest with closed canopy, arbuscules had the highest percentages of colonization; on these sites the palm has been observed to grow less. The higher production of arbuscules may favour nutrient capture in this microenvironment, which is characterized by strong competition.

  17. Proline and Abscisic Acid Content in Droughted Corn Plant Inoculated with Azospirillum sp. and Arbuscular Mycorrhizae Fungi

    Directory of Open Access Journals (Sweden)

    NOVRI YOULA KANDOWANGKO

    2009-03-01

    Full Text Available Plants that undergo drought stress perform a physiological response such as accumulation of proline in the leaves and increased content abscisic acid. A research was conducted to study proline and abscisic acid (ABA content on drought-stressed corn plant with Azospirillum sp. and arbuscular mycorrhizae fungi (AMF inoculated at inceptisol soil from Bogor, West Java. The experiments were carried out in a green house from June up to September 2003, using a factorial randomized block design. In pot experiments, two factors were assigned, i.e. inoculation with Azospirillum (0, 0.50, 1.00, 1.50 ml/pot and inoculation with AMF Glomus manihotis (0, 12.50, 25.00, 37.50 g/pot. The plants were observed during tasseling up to seed filling periods. Results of experiments showed that the interaction between Azospirillum sp. and AMF was synergistically increased proline, however it decreased ABA.

  18. Mycorrhiza and heavy metal resistant bacteria enhance growth, nutrient uptake and alter metabolic profile of sorghum grown in marginal soil.

    Science.gov (United States)

    Dhawi, Faten; Datta, Rupali; Ramakrishna, Wusirika

    2016-08-01

    The main challenge for plants growing in nutrient poor, contaminated soil is biomass reduction, nutrient deficiency and presence of heavy metals. Our aim is to overcome these challenges using different microbial combinations in mining-impacted soil and focus on their physiological and biochemical impacts on a model plant system, which has multiple applications. In the current study, sorghum BTx623 seedlings grown in mining-impacted soil in greenhouse were subjected to plant growth promoting bacteria (PGPB or B) alone, PGPB with arbuscular mycorrhizal fungi (My), My alone and control group with no treatment. Root biomass and uptake of most of the elements showed significant increase in all treatment groups in comparison with control. Mycorrhiza group showed the best effect followed by My + B and B groups for uptake of majority of the elements by roots. On the contrary, biomass of both shoot and root was more influenced by B treatment than My + B and My treatments. Metabolomics identified compounds whose levels changed in roots of treatment groups significantly in comparison to control. Upregulation of stearic acid, sorbitol, sebacic acid and ferulic acid correlated positively with biomass and uptake of almost all elements. Two biochemical pathways, fatty acid biosynthesis and galactose metabolism, were regulated in all treatment groups. Three common pathways were upregulated only in My and My + B groups. Our results suggest that PGPB enhanced metabolic activities which resulted in increase in element uptake and sorghum root biomass whether accompanied with mycorrhiza or used solely. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. The role of mycorrhizae and plant growth promoting rhizobacteria (PGPR) in improving crop productivity under stressful environments.

    Science.gov (United States)

    Nadeem, Sajid Mahmood; Ahmad, Maqshoof; Zahir, Zahir Ahmad; Javaid, Arshad; Ashraf, Muhammad

    2014-01-01

    Both biotic and abiotic stresses are major constrains to agricultural production. Under stress conditions, plant growth is affected by a number of factors such as hormonal and nutritional imbalance, ion toxicity, physiological disorders, susceptibility to diseases, etc. Plant growth under stress conditions may be enhanced by the application of microbial inoculation including plant growth promoting rhizobacteria (PGPR) and mycorrhizal fungi. These microbes can promote plant growth by regulating nutritional and hormonal balance, producing plant growth regulators, solubilizing nutrients and inducing resistance against plant pathogens. In addition to their interactions with plants, these microbes also show synergistic as well as antagonistic interactions with other microbes in the soil environment. These interactions may be vital for sustainable agriculture because they mainly depend on biological processes rather than on agrochemicals to maintain plant growth and development as well as proper soil health under stress conditions. A number of research articles can be deciphered from the literature, which shows the role of rhizobacteria and mycorrhizae alone and/or in combination in enhancing plant growth under stress conditions. However, in contrast, a few review papers are available which discuss the synergistic interactions between rhizobacteria and mycorrhizae for enhancing plant growth under normal (non-stress) or stressful environments. Biological interactions between PGPR and mycorrhizal fungi are believed to cause a cumulative effect on all rhizosphere components, and these interactions are also affected by environmental factors such as soil type, nutrition, moisture and temperature. The present review comprehensively discusses recent developments on the effectiveness of PGPR and mycorrhizal fungi for enhancing plant growth under stressful environments. The key mechanisms involved in plant stress tolerance and the effectiveness of microbial inoculation for

  20. [Development of Arbuscular Mycorrhiza in Highly Responsive and Mycotrophic Host Plant-Black Medick (Medicago lupulina L.)].

    Science.gov (United States)

    Yurkova, A P; Jacobi, L M; Gapeeva, N E; Stepanova, G V; Shishova, M F

    2015-01-01

    The main phases of arbuscular mycorrhiza (AM) development were analyzed in black medick (Medicago lupulina) with Glomus intraradices. Methods of light and transmission electron microscopy were used to investigate AM. The first mycorrhization was identified on the seventh day after sowing. M. lupulina with AM-fungus Glomus intraradices formed Arum type of AM. Roots of black medick at fruiting stage (on the 88th day) were characterized by the development of forceful mycelium. The thickness of mycelium was comparable with the vascular system of root central cylinder. The development of vesicules into intraradical spores was shown. Micelium, arbuscules, and vesicules developed in close vicinity to the division zone of root tip. This might be evidence of an active symbiotic interaction between partners. All stages of fungal development and breeding, including intraradical spores (in inter-cellular matrix of root cortex), were identified in the roots of black medick, which indicated an active utilization of host plant nutrient substrates by the mycosymbiont. Plant cell cytoplasm extension was identified around young arbuscular branches but not for intracellular hyphae. The presence of active symbiosis was confirmed by increased accumulation of phosphorus in M. lupulina root tissues under conditions of G. intraradices inoculation and low phosphorus level in the soil. Thus, black medick cultivar-population can be characterized as an ecologically obligate mycotrophic plant under conditions of low level of available phosphorus in the soil. Specific features of AM development in intensively mycotrophic black medick, starting from the stage of the first true leaf until host plant fruiting, were evaluated. The obtained plant-microbe system is a perspective model object for further ultracytological and molecular genetic studies of the mechanisms controlling arbuscular mycorrhiza symbiotic efficiency, including selection and investigation of new symbiotic plant mutants.

  1. Bacterial effects on arbuscular mycorrhizal fungi and mycorrhiza development as influenced by the bacteria, fungi, and host plant.

    Science.gov (United States)

    Pivato, Barbara; Offre, Pierre; Marchelli, Sara; Barbonaglia, Bruno; Mougel, Christophe; Lemanceau, Philippe; Berta, Graziella

    2009-02-01

    Bacterial strains from mycorrhizal roots (three belonging to Comamonadaceae and one to Oxalobacteraceae) and from non-mycorrhizal roots (two belonging to Comamonadaceae) of Medicago truncatula and two reference strains (Collimonas fungivorans Ter331 and Pseudomonas fluorescens C7R12) were tested for their effect on the in vitro saprophytic growth of Glomus mosseae BEG12 and on its colonization of M. truncatula roots. Only the Oxalobacteraceae strain, isolated from barrel medic mycorrhizal roots, and the reference strain P. fluorescens C7R12 promoted both the saprophytic growth and root colonization of G. mosseae BEG12, indicating that they acted as mycorrhiza helper bacteria. Greatest effects were achieved by P. fluorescens C7R12 and its influence on the saprophytic growth of G. mosseae was compared to that on Gigaspora rosea BEG9 to determine if the bacterial stimulation was fungal specific. This fungal specificity, together with plant specificity, was finally evaluated by comparing bacterial effects on arbuscular mycorrhizal symbiosis when each of the fungal species was inoculated to two different plant species (M. truncatula and Lycopersicon esculentum). The results obtained showed that promotion of saprophytic growth by P. fluorescens C7R12 was expressed in vitro towards G. mosseae but not towards G. rosea. Bacterial promotion of mycorhization was also expressed towards G. mosseae, but not G. rosea, in roots of M. truncatula and L. esculentum. Taken together, results indicated that enhancement of arbuscular mycorrhiza development was only induced by a limited number of bacteria, promotion by the most efficient bacterial strain being fungal and not plant specific.

  2. Evaluation of Two Mycorrhiza Species and Nitroxin on Yield and Yield Components of Garlic (Allium sativum L. in an Ecological Agroecosystem

    Directory of Open Access Journals (Sweden)

    P Rezvani Moghaddam

    2016-02-01

    Full Text Available Introduction Maintenance of soil fertility is one of the most important issues affecting the sustainability of food production. The application of ecological inputs such as mycorrhiza and biofertilizers are one of those approaches which are needed to maintain soil fertility Biofetilizers include different types of free living organisms that convert unavailable nutrients to available forms and enhance root development and better seed germination. Plant growth promoting rhizobacteria (PGPR occupy the rhizosphere of many plant species and have beneficial effects on the host plant. They may directly and indirectly influence the plant growth. A direct mechanism would be to increase plant growth by supplying the plant with nutrients and hormones. Indirect mechanisms, on the other hand, include reduced susceptibility to diseases and acting as a form of defense referred to as induces systematic resistance. Mycorrhiza arbuscular fungi are other coexist microorganisms that improve soil fertility, nutrients cycling and agroecosystem health. Mycorrhizal fungi are the most abundant organisms in agricultural soils. Many researchers have pointed to the positive roles of mycorrhizal fungi on plants growth characteristics. Arbuscular mycorrhizas are found in 85% of all plant families and occur in many crop species. Mineral nutrients such as potassium, calcium, copper, zinc and iron are assimilated more quickly and in greater amounts by mycorrhizal plants. Arbuscular mycorrhizal inoculation has also been shown to increase plant resistance of pathogen attack. Garlic (Allium sativum L. is a very powerful medicinal plant that is often underestimated. Garlic is easy to grow and can be grown year-round in any mild climates. Garlic cloves are used for consumption (row and cooked or for medicinal purposes. They have a characteristic pungent, spicy flavor that mellows and sweetens considerably with cooking. Despite of many studies on the effects of mycorrhiza and

  3. Regulação do desenvolvimento de micorrizas arbusculares Regulation of arbuscular mycorrhizae development

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    Soraya Gabriela Kiriachek

    2009-02-01

    Full Text Available As micorrizas arbusculares (MAs são associações simbióticas mutualistas entre fungos do filo Glomeromycota e a maioria das plantas terrestres. A formação e o funcionamento das MAs depende de um complexo processo de troca de sinais, que resulta em mudanças no metabolismo dos simbiontes e na diferenciação de uma interface simbiótica no interior das células das raízes. Os mecanismos que regulam a formação das MAs são pouco conhecidos, mas sabe-se que a concentração de fosfato (P na planta é um fator determinante para o desenvolvimento da simbiose. A disponibilidade de P na planta pode afetar o balanço de açúcares e de fitormônios (FHs, além da expressão de genes de defesa vegetal. Com o advento da genômica e proteômica, vários genes essenciais para o desenvolvimento das MAs já foram identificados e seus mecanismos de regulação estão sendo estudados. Até o presente, sabe-se que as plantas secretam substâncias que estimulam a germinação de esporos e o crescimento de fungos micorrízicos arbusculares (FMAs. Há evidências também de que os FMAs sintetizam moléculas sinalizadoras, que são reconhecidas pelas plantas hospedeiras. Pelo menos três genes são essenciais para o reconhecimento dessa molécula e a transdução do sinal molecular. Discutem-se os papéis desses genes e os possíveis mecanismos que regulam sua expressão, bem como os papéis dos FHs na regulação de MAs são discutidos.Arbuscular mycorrhizae (AM are mutualistic symbiotic associations between fungi of the phylum Glomeromycota and most terrestrial plants. The formation and functioning of AM depend on a complex signal exchange process, which ultimately results in shifts in the metabolism of the symbionts and differentiation of a symbiotic interface in cortical root cells. The mechanisms regulating AM development are not well understood, but it is known that phosphate (P concentration in plants plays a key role in this process. Plant P

  4. Establishment of Desmoncus orthacanthos Martius (Arecaceae: effect of inoculation with arbuscular mycorrhizae

    Directory of Open Access Journals (Sweden)

    José A Ramos-Zapata

    2006-03-01

    Full Text Available Inoculation with arbuscular mycorrhizal (AM fungi has often promoted increased growth of plants but very little work has been done in the tropics to evaluate the effects of inoculation on the establishment and development of seedlings in forests. Desmoncus orthacanthos Martius is a scandent palm present both in early and late succession, and consequently can be used in restoration processes. A test was conducted to determine the effect of AM on the establishment of Desmoncus orthacanthos in tropical forest in the Yucatan Peninsula, Mexico. Thirty inoculated and 30 non-inoculated seedlings were introduced in two sites of different successional age, a mature forest and an eight-year old abandoned cornfield (acahual.Survival and growth parameters were evaluated after 12 months. Leaf area and phosphorus, but not height, were greater in inoculated than non-inoculated plants in the forest but not in the acahual. However, mycorrhizae had a clear effect on plant survival in both sites, with a threefold increase in survival of inoculated compared with non-inoculated plants bassed on an odds ratio. The results suggest that inoculation will be important to increase the establishment of this commercially important palm. Rev. Biol. Trop. 54(1: 65-72. Epub 2006 Mar 31.La inoculación con hongos micorrizógenos arbusculares (AMpromueve un incremento en el crecimiento de las plantas, sin embargo poco trabajo se ha realizado en los trópicos para evaluar el efecto de la inoculación en el proceso de establecimiento de plántulas. Desmoncus orthacanthos Martius es una palmera trepadora que se distribuye tanto en etapas tempranas y tardías de la sucesión, por lo tanto puede ser empleada en procesos de restauración. Se realizó una prueba de establecimiento de D. orthacanthos en una selva tropical de la península de Yucatán, México. Treinta plántulas inoculadas y 30 no inoculadas se establecieron en dos sitios con diferentes etapas sucesionales: selva madura

  5. Mycorrhiza formation and nutrient concentration in leeks (¤Allium porrum¤) in relation to previous crop and cover crop management on high P soils

    DEFF Research Database (Denmark)

    Sørensen, J.N.; Larsen, J.; Jakobsen, I.

    2005-01-01

    cover crops. Experiments on soils with moderate to high P content (26-50 mg kg(-1) bicarbonate-extractable P) showed that the previous crop influenced mycorrhiza formation, uptake of P, Zn, and Cu, and early growth of leek seedlings. A cover crop of black medic, established the previous autumn......An improved integration of mycorrhizas may increase the sustainability in plant production. Two strategies for increasing the soil inoculum potential of mycorrhizal fungi were investigated in field experiments with leeks: Pre-cropping with mycorrhizal main crops and pre-establishment of mycorrhizal...... or tillage treatments. Differences in colonization, nutrient uptake and plant growth diminished during the growing period and at the final harvest date, the effects on plant production disappeared. High soil P level or high soil inoculum level was most likely responsible for the limited response of increased...

  6. [Effects of ryegrass and arbuscular mycorrhiza on activities of antioxidant enzymes, accumulation and chemical forms of cadmium in different varieties of tomato].

    Science.gov (United States)

    Jiang, Ling; Yang, Yun; Xu, Wei-Hong; Wang, Chong-Li; Chen, Rong; Xiong, Shi-Juan; Xie, Wen-Wen; Zhang, Jin-Zhong; Xiong, Zhi-Ting; Wang, Zheng-Yin; Xie, De-Ti

    2014-06-01

    Pot experiments were carried out to investigate the effects of ryegrass and arbuscular mycorrhiza on the plant growth, malondialdehyde (MDA), antioxidant enzyme activities of leaf and root, accumulation and chemical forms of cadmium (Cd) in tow varieties of tomato when exposed to Cd (20 mg x kg(-1)). The results showed that dry weights of fruit and plant, and contents of malondialdehyde (MDA) and antioxidant enzyme activities of leaf and root, and concentrations and accumulations of Cd significantly differed between two varieties of tomato. Dry weights of fruit, roots, stem, leaf and plant were increased by single or combined remediation of ryegrass and arbuscular mycorrhiza, while MDA contents and antioxidant enzyme activities of leaf and root reduced. The total extractable Cd, F(E), F(W), F(NaCl), F(HAc), F(HCl), and F(R) in fruit of two varieties of tomato reduced by 19.4% - 52.4%, 31.0% - 75.2%, 19.7% - 59.1%, 3.1% - 48.2%, 20.0% - 65.0%, 40.7% - 100.0% and 15.2% - 50.0%, respectively. Cadmium accumulations in tomato were in the order of leaf > stem > fruit > root. Cadmium concentrations in leaf, stem, root and fruit of both varieties decreased by single or combined remediation of ryegrass and arbuscular mycorrhiza, and Cd accumulations of stem and plant of two varieties also reduced. Cd accumulations in fruit of two varieties decreased by 42.9% and 43.7% in the combined remediation treatments, respectively. Tolerance and resistance of 'LUO BEI QI' on Cd was more than 'De Fu mm-8', and Cd concentrations and Cd accumulations in fruit and plant were in the order of 'LUO BEI QI' mycorrhiza.

  7. High-resolution secondary ion mass spectrometry analysis of carbon dynamics in mycorrhizas formed by an obligately myco-heterotrophic orchid.

    Science.gov (United States)

    Bougoure, Jeremy; Ludwig, Martha; Brundrett, Mark; Cliff, John; Clode, Peta; Kilburn, Matt; Grierson, Pauline

    2014-05-01

    Mycorrhiza formation represents a significant carbon (C) acquisition alternative for orchid species, particularly those that remain achlorophyllous through all life stages. As it is known that orchid mycorrhizas facilitate nutrient transfer (most notably of C), it has not been resolved if C transfer occurs only after lysis of mycorrhizal structures (fungal pelotons) or also across the mycorrhizal interface of pre-lysed pelotons. We used high-resolution secondary ion mass spectrometry (nanoSIMS) and labelling with enriched (13) CO2 to trace C transfers, at subcellular scale, across mycorrhizal interfaces formed by Rhizanthella gardneri, an achlorphyllous orchid. Carbon was successfully traced in to the fungal portion of orchid mycorrhizas. However, we did not detect C movement across intact mycorrhizal interfaces up to 216 h post (13) CO2 labelling. Our findings provide support for the hypothesis that C transfer from the mycorrhizal fungus to orchid, at least for R. gardneri, likely occurs after lysis of the fungal peloton. © 2013 John Wiley & Sons Ltd.

  8. Rhizobacteria in mycorrhizosphere improved plant health and yield of banana by offering proper nourishment and protection against diseases.

    Science.gov (United States)

    Phirke, Niteen V; Kothari, Raman M; Chincholkar, Sudhir B

    2008-12-01

    The corporate R&D banana orchards of Musa paradisiaca (dwarf Cavendish AAA, var. shrimanti) on a medium black alluvial soil with low nutrients harboured diversified species of vesicular-arbuscular mycorrhizal (VAM) fungi. These fungi infected the roots severely (69.2%), showed elevated (69.8 g(-1) soil) spore density, increased soil bacterial density (245 x 10(8) cfu g(-1)), produced siderophores (58.2%) and reduced nematode population (2.3 g(-1)) in the mycorrhizosphere of plants for integrated plant nutrition management (IPNM) system as compared to traditional treatment of applying chemical fertilisers alone and other test treatments. The interactions of plant roots with native VAM and local and applied rhizobacteria in the matrix of soil conditioner enabled proper nourishment and protection of crop in IPNM treatment as compared to traditional way. Hence, exploitation of plant growth promoting rhizobacteria through judiciously designed IPNM system revealed the (a) relatively increased banana productivity (21.6%, 76 MT ha(-1)), (b) least occurrence of fusarial wilt and negligible evidence of Sigatoka, (c) saving of 50% chemical fertilisers and (d) permitted control over soil fertility in producer's favour over traditional cultivation practices. These findings are discussed in detail.

  9. Root foraging for Patchy Phosphorus of Plant Species with Contrasting Foraging Strategy - Role of Roots and Mycorrhiza

    Science.gov (United States)

    Felderer, B.; Robinson, B. H.; Jansa, J.; Vontobel, P.; Frossard, E.; Schulin, R.

    2009-04-01

    Plant nutrients are distributed heterogeneously in soil. Thus the nutrient distribution together with nutrient availability, temporal and spatial development of roots determine nutrient uptake by the plants. Plants have developed several strategies to cope with the patchy nutrient distribution. Preferential root development within nutrient-enriched patches is a prominent response to heterogeneous nutrient distribution. This capacity to precisely allocate roots is called morphological plasticity and is highly variable between plant species. Another strategy is the increased nutrient uptake per unit of root surface in the nutrient-rich patches as compared to root zones outside such patches, so-called physiological plasticity . Additionally, enhanced nutrient uptake from nutrient-rich patches might be supported by increased production of mycorrhizal extraradical hyphae. We refer to this phenomenon as plastic response of the mycorrhiza-plant association. Relative importance for nutrient acquisition of these responses to heterogeneous nutrient distribution might vary between plant species. However, quantitative data are very rare. We will investigate nutrient acquisition and root development over time in sandy substrate with heterogeneous phosphorus (P) distribution of two model plant species with different nutrient foraging strategies (Lotus corniculatus, Trifolium arvense). These plant species are characterized by high and low morphological plasticity, respectively (according to results of preliminary experiments). We follow three main goals in a single mesocosm experiment, where P is to be homogeneously or patchily distributed in a sandy substrate: 1. - Imaging of root architecture of Lotus corniculatus and Trifolium arvense on a time line. 2. - Assessment of the physiological plasticity of Lotus corniculatus and Trifolium arvense 3. - Determination of the plasticity of mycorrhiza-plant association of Lotus corniculatus and Trifolium arvense associated with either of

  10. Tuber melanosporum spread within sub-optimal climatic zones is controlled by fruiting triggers and not mycorrhiza survival

    Directory of Open Access Journals (Sweden)

    Paul W. Thomas

    2014-07-01

    Full Text Available Tuber melanosporum is the most valuable of all cultivatable truffle species. Farming of this species spans every continent with the exception of Antarctica. Tuber aestivum (syn. T. uncinatum and Tuber brumale are truffle species that have similar host plant preference and a similar affinity for calcareous soils as T. melanosporum, but occur over a broader geographic zone. The geographic limit of T. melanosporum is thought to be climatically dictated but it is not known whether this is due to an impact on mycorrhizal survival or climatically-derived fruiting triggers. Here, data is compiled from five cultivated research sites in the climatically sub-optimal conditions of the UK in order to address this question. Here we show: (iTuber melanosporum mycorrhiza can survive and grow in sub-optimal climatic conditions. (iiIt is climatically-derived fruiting triggers and not ectomycorrhiza survival that dictate the climatic preferences and geographic spread of T. melanosporum. (iiiImportant climatic parameters for potential fruiting triggers are sunshine hours, summer rainfall and summer temperatures.   The data presented here not only aid our understanding of the ecological parameters of T. melanosporum but also have a practical application for truffle cultivators in choosing suitable locations for a plantation.

  11. Colonization of Greek olive cultivars' root system by arbuscular mycorrhiza fungus: root morphology, growth, and mineral nutrition of olive plants

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    Theocharis Chatzistathis

    2013-06-01

    Full Text Available Rooted leafy cuttings of three Greek olive (Olea europaea L. cultivars (Koroneiki, Kothreiki and Chondrolia Chalkidikis were grown for six months in three soil types, in an experimental greenhouse, in order to investigate: i if their root system was colonized by arbuscular mycorrhiza fungus (AMF genus and, ii if genotypic differences concerning growth and mineral nutrition of olive plants existed. Gigaspora sp. colonized the root system of the three cultivars studied, while Glomus sp. colonized only the root system of 'Koroneiki'. Furthermore, in most cases root colonization by AMF differed among cultivars and soil types. The maximum root colonization, in all soils, was found in 'Chondrolia Chalkidikis'. In the three soils studied, the ratio shoot dry weight (SDW/ root dry weight (RDW was higher in 'Chondrolia Chalkidikis' than in the other two cultivars. Furthermore, root system morphology of the three olive cultivars was completely different, irrespectively of soil type. Leaf Mn, Fe, Zn, Ca, Mg, K and P concentrations, as well as total per plant nutrient content and nutrient use efficiency, differed among cultivars under the same soil conditions. These differences concerning root morphology, SDW/RDW, as well as nutrient uptake and use efficiency, could be possibly ascribed to the differential AMF colonization by Glomus sp. and Gigaspora sp.

  12. The Impacts of Mycorrhiza and Phsphorus Along with the Use of Salicylic Acid on Maize Seed Yield

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    Fedra Taheri Oshtrinani

    2016-10-01

    Full Text Available The effects of biological and chemical fertilizers, along with the use of salicylic acid, on the agronomic characteristics of corn in a factorial experiment based on randomized complete block design with three replications were evaluated at the Agricultural Research Station of Boroujerd in 2011. Factors were three levels of phosphorus fertilizer (0, 100 and 150 kg ha, two levels of biological fertilizers (mycorrhizal fungi (inoculation and non- inoculation of seeds and two levels of salicylic acid (0.5 and 1 mM, respectively. The results showed that phosphorus fertilizer and mycorrhizal inoculation of seeds affected number of seed rows, seed weight, seed yield and biological yield significantly. Seed yield of plants inoculated with mycorrhiza was 8412 kg.ha-1 which is 24% higher than non-inoculated ones. The effect of salicylic acid on plant height, stem diameter, ear length, ear diameter, number of seed rows, seed weight, seed yield and biological yield and harvest index was also significant. The yield of plants with 1 mM salicylic acid treatment amounted to be 8316 kg.ha-1 which is 24% higher than none treated ones. Phosphorus and mycorrhizal interaction on the number of rows of seeds, seed weight, seed yield and biological yield were significant. Salicylic acid and phosphorus interactions and three way treatment effects were only significant on grain yield. This study showed that salicylic acid and mycorrhizal inoculation of seeds can increase seed yield by improving yield components.

  13. [Effects of arbuscular mycorrhiza fungi (AMF) on the plant growth, fruit yield, and fruit quality of cucumber under salt stress].

    Science.gov (United States)

    Han, Bing; Guo, Shi-Rong; He, Chao-Xing; Yan, Yan; Yu, Xian-Chang

    2012-01-01

    By adopting organic substrate culture, and salt-sensitive cucumber variety 'Jinchun No. 2' was used as test material, this paper studied the effects of inoculating arbuscular mycorrhiza fungi (AMF) on the plant growth, fruit yield, and fruit quality of cucumber under salt stress. AMF-inoculation could effectively promote the plant growth and nutrient uptake, and improve the fruit yield and fruit nutrient quality, compared with ordinary cultivation. Under salt stress, the plant growth was inhibited, and the plant N, P, K, Cu, and Zn contents and K+/Na+ ratio, fruit yield, and fruit soluble protein, total sugar, vitamin C, and nitrate contents decreased, while inoculation with AMF could mitigate the inhibitory effect of salt stress on the plant growth, made the plant N, P, K, Cu, and Zn contents increased by 7.3%, 11.7%, 28.2%, 13.5%, and 9.9%, respectively, and made the plant K+/Na+ ratio, fruit yield, and fruit soluble protein, total sugar, and vitamin C contents have an obvious increase and the fruit nitrate content have a significant decrease. It was suggested that AMF could promote the plant growth and nutrient uptake of cucumber under salt stress, increase the plant salt-tolerance, and improve the fruit yield and its nutrient quality.

  14. Effects of biochar and Arbuscular mycorrhizae on bioavailability of potentially toxic elements in an aged contaminated soil.

    Science.gov (United States)

    Qiao, Yuhui; Crowley, David; Wang, Kun; Zhang, Huiqi; Li, Huafen

    2015-11-01

    Biochar pyrolyzed from corn stalks at 300°C/500°C and arbuscular mycorrhizae (AMF) were examined independently and in combination as possible treatments for soil remediation contaminated with Cd, Cr, Ni, Cu, Pb, Zn after 35 years following land application of sewage sludge in the 1970s. The results showed that biochar significantly decreased the heavy metal concentrations and their bioavailability for plants, and both biochars had similar such effects. AMF inoculation of corn plants had little effect on heavy metal bioavailability in either control or biochar amended soil, and no interaction between biochar and AMF was observed. Changes in DTPA extractable metals following biochar addition to soil were correlated with metal uptake by plants, whereas pore water metal concentrations were not predictive indicators. This research demonstrates positive benefits from biochar application for contaminated soil remediation, but remain ambiguous with regard to the benefits of simultaneous AMF inoculation on reduction of heavy metal bioavailability. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Agricultural practices to improve nitrogen use efficiency through the use of arbuscular mycorrhizae: Basic and agronomic aspects.

    Science.gov (United States)

    Verzeaux, Julien; Hirel, Bertrand; Dubois, Frédéric; Lea, Peter J; Tétu, Thierry

    2017-11-01

    Nitrogen cycling in agroecosystems is heavily dependent upon arbuscular mycorrhizal fungi (AMF) present in the soil microbiome. These fungi develop obligate symbioses with various host plant species, thus increasing their ability to acquire nutrients. However, AMF are particularly sensitive to physical, chemical and biological disturbances caused by human actions that limit their establishment. For a more sustainable agriculture, it will be necessary to further investigate which agricultural practices could be favorable to maximize the benefits of AMF to improve crop nitrogen use efficiency (NUE), thus reducing nitrogen (N) fertilizer usage. Direct seeding, mulch-based cropping systems prevent soil mycelium disruption and increase AMF propagule abundance. Such cropping systems lead to more efficient root colonization by AMF and thus a better establishment of the plant/fungal symbiosis. In addition, the use of continuous cover cropping systems can also enhance the formation of more efficient interconnected hyphal networks between mycorrhizae colonized plants. Taking into account both fundamental and agronomic aspects of mineral nutrition by plant/AMF symbioses, we have critically described, how improving fungal colonization through the reduction of soil perturbation and maintenance of an ecological balance could be helpful for increasing crop NUE. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. The influence of arbuscular mycorrhizae and light on Wisconsin (USA) sand savanna understories 1. Plant community composition.

    Science.gov (United States)

    Landis, Frank C; Gargas, Andrea; Givnish, Thomas J

    2005-11-01

    To explain the complex community composition found in Wisconsin (USA) oak savannas, we investigated potentially interacting effects of light gradients and arbuscular mycorrhizal fungi (AMF) on community composition in the greenhouse, using a fully randomized block experimental design. We used plant species, soil, and AMF from a remnant sand savanna in setting up the experiment, using two light and five AMF treatments. Eleven plant species were seeded into 80 microcosms, and they were grown together for 20 weeks. Plant numbers and biomass were measured, and Simpson's index was calculated for both. Data were analyzed using ANOVA and nonparametric ANOVA. We found significant light effects on biomass and on numbers of four species. There were no treatment effects on Simpson's index, and only Schizachyrium numbers showed a significant AMF effect. These findings are consistent with results from other studies of the sand savanna, and, collectively, these data suggest that plant community composition in this species-rich savanna is not strongly influenced by arbuscular mycorrhizae. This is a novel finding with important implications for understanding interactions between plant and AMF diversity in wild communities.

  17. Ectomycorrhization of Tricholoma matsutake and two major conifers in Finland-an assessment of in vitro mycorrhiza formation.

    Science.gov (United States)

    Vaario, Lu-Min; Pennanen, Taina; Sarjala, Tytti; Savonen, Eira-Maija; Heinonsalo, Jussi

    2010-10-01

    This study aimed to test the ability of Tricholoma matsutake isolates to form mycorrhizas with aseptic seedlings of Pinus sylvestris L. and Picea abies (L.) Karst. Germinated seedlings of Scots pine and Norway spruce were separately inoculated with either isolates originating from Finland or Japan. Eight months after inoculation, the Finnish isolate had formed a sheath and Hartig net on both host species. Ectomycorrhizal Scots pine seedlings inoculated with the Finnish isolate showed the same shoot height and dry mass as the controls. Ectomycorrhizal Norway spruce seedlings inoculated with the Finnish isolate had similar shoot height but slightly less dry mass than the control seedlings. For both tree species, inoculation with the Finnish isolate resulted in reduced total nitrogen content per seedling, but carbon content was unaffected. Inoculation with the Japanese isolate resulted in an initial Hartig net-like structure in pine but not in spruce. No typical Hartig net was observed on either tree species. Furthermore, seedlings of both species inoculated with the Japanese isolate showed significantly reduced growth, dry mass, nitrogen, and carbon content per seedling and shoot height (in spruce) compared to the controls. This study documents and describes the in vitro ectomycorrhization between T. matsutake and Scots pine or Norway spruce and the variable mycorrhizal structures that matsutake isolates can form.

  18. Mycorrhiza and PGPB modulate maize biomass, nutrient uptake and metabolic pathways in maize grown in mining-impacted soil.

    Science.gov (United States)

    Dhawi, Faten; Datta, Rupali; Ramakrishna, Wusirika

    2015-12-01

    Abiotic stress factors including poor nutrient content and heavy metal contamination in soil, can limit plant growth and productivity. The main goal of our study was to evaluate element uptake, biomass and metabolic responses in maize roots growing in mining-impacted soil with the combination of arbuscular mycorrhiza (My) and plant growth promoting bacteria (PGPB/B). Maize plants subjected to PGPB, My and combined treatments showed a significant increase in biomass and uptake of some elements in shoot and root. Metabolite analysis identified 110 compounds that were affected ≥2-fold compared to control, with 69 metabolites upregulated in the My group, 53 metabolites in the My+B group and 47 metabolites in B group. Pathway analysis showed that impact on glyoxylate and dicarboxylate metabolism was common between My and My+B groups, whereas PGPB group showed a unique effect on fatty acid biosynthesis with significant increase in palmitic acid and stearic acid. Differential regulation of some metabolites by mycorrhizal treatment correlated with root biomass while PGPB regulated metabolites correlated with biomass increase in shoot. Overall, the combination of rhizospheric microorganisms used in our study significantly increased maize nutrient uptake and growth relative to control. The changes in metabolic pathways identified during the symbiotic interaction will improve our understanding of mechanisms involved in rhizospheric interactions that are responsible for increased growth and nutrient uptake in crop plants. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  19. Influence of arbuscular mycorrhiza on lipid peroxidation and antioxidant enzyme activity of maize plants under temperature stress.

    Science.gov (United States)

    Zhu, Xiancan; Song, Fengbin; Xu, Hongwen

    2010-06-01

    The influence of the arbuscular mycorrhizal (AM) fungus, Glomus etunicatum, on characteristics of growth, membrane lipid peroxidation, osmotic adjustment, and activity of antioxidant enzymes in leaves and roots of maize (Zea mays L.) plants was studied in pot culture under temperature stress. The maize plants were placed in a sand and soil mixture under normal temperature for 6 weeks and then exposed to five different temperature treatments (5 degrees C, 15 degrees C, 25 degrees C, 35 degrees C, and 40 degrees C) for 1 week. AM symbiosis decreased membrane relative permeability and malondialdehyde content in leaves and roots. The contents of soluble sugar content and proline in roots were higher, but leaf proline content was lower in mycorrhizal than nonmycorrhizal plants. AM colonization increased the activities of superoxide dismutase, catalase, and peroxidase in leaves and roots. The results indicate that the AM fungus is capable of alleviating the damage caused by temperature stress on maize plants by reducing membrane lipid peroxidation and membrane permeability and increasing the accumulation of osmotic adjustment compounds and antioxidant enzyme activity. Consequently, arbuscular mycorrhiza formation highly enhanced the extreme temperature tolerance of maize plant, which increased host biomass and promoted plant growth.

  20. Interaction of brassinosteroid functions and sucrose transporter SlSUT2 regulate the formation of arbuscular mycorrhiza.

    Science.gov (United States)

    Bitterlich, Michael; Krügel, Undine; Boldt-Burisch, Katja; Franken, Philipp; Kühn, Christina

    2014-01-01

    Transgenic tomato plants with reduced expression of the sucrose transporter SlSUT2 showed higher efficiency of mycorrhization suggesting a sucrose retrieval function of SlSUT2 from the peri-arbuscular space back into the cell cytoplasm plant cytoplasm thereby limiting mycorrhiza fungal development. Sucrose uptake in colonized root cells requires efficient plasma membrane-targeting of SlSUT2 which is often retained intracellularly in vacuolar vesicles. Protein-protein interaction studies suggested a link between SISUT2 function and components of brassinosteroid biosynthesis and signaling. Indeed, the tomato DWARF mutant d(x) defective in BR synthesis (1) showed significantly reduced mycorrhization parameters. (2) The question has been raised whether the impact of brassinosteroids on mycorrhization is a general phenomenon. Here, we include a rice mutant defective in DIM1/DWARF1 involved in BR biosynthesis to investigate the effects on mycorrhization. A model is presented where brassinolides are able to impact mycorrhization by activating SUT2 internalization and inhibiting its role in sucrose retrieval.

  1. Arbuscular mycorrhiza of Deschampsia cespitosa (Poaceae at different soil depths in highly metal-contaminated site in southern Poland

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    Ewa Gucwa-Przepióra

    2013-12-01

    Full Text Available This study presents root colonization of Deschampsia cespitosa growing in the immediate vicinity of a former Pb/Zn smelter by arbuscular mycorhizal fungi (AMF and dark septated endophytes (DSE at different soil depths. AMF spores and species distribution in soil profile were also assessed. Arbuscular mycorrhiza (AM and DSE were found in D. cespitosa roots at all investigated soil levels. However, mycorrhizal colonization in topsoil was extremely low with sporadically occurring arbuscules. AM parameters: frequency of mycorrhization of root fragments (F%, intensity of root cortex colonization (M%, intensity of colonization within individual mycorrhizal roots (m%, and arbuscule abundance in the root system (A% were markedly higher at 20–40, 40–60 cm soil levels and differed in a statistically significant manner from AM parameters from 0–10 and 10–20 cm layers. Mycorrhizal colonization was negatively correlated with bioavailable Cd, Pb and Zn concentrations. The number of AMF spores in topsoil was very low and increased with soil depth (20–40 and 40–60 cm. At the study area spores of three morphologically distinctive AMF species were found: Archaeospora trappei, Funneliformis mosseae and Scutellospora dipurpurescens. The fourth species Glomus tenue colonized roots of D. cespitosa and was observed in the root cortex at 20–40 and 40–60 soil depth, however, its spores were not found at the site.

  2. Observations on arbuscular mycorrhiza associated with important edible tuberous plants grown in wet evergreen forest in Assam, India

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    RAJA RISHI

    2013-10-01

    Full Text Available Kumar R, Tapwal A, Pandey S, Rishi R, Borah D. 2013. Observations on arbuscular mycorrhiza associated with important edible tuberous plants grown in wet evergreen forest in Assam, India. Biodiversitas 14: 67-72. Non-timber forest products constitute an important source of livelihood for rural households from forest fringe communities across the world. Utilization of wild edible tuber plants is an integral component of their culture. Mycorrhizal associations influence the establishment and production of tuber plants under field conditions.The aim of present study is to explore the diversity and arbuscular mycorrhizal (AMF colonization of wild edible tuber plants grown in wet evergreen forest of Assam, India. A survey was conducted in 2009-10 in Sunaikuchi, Khulahat, and Bura Mayong reserved forest of Morigaon district of Assam to determine the AMF spore population in rhizosphere soils and root colonization of 14 tuberous edible plants belonging to five families. The results revealed AMF colonization of all selected species in all seasons. The percent colonization and spore count was less in summer, moderate in winter and highest in rainy season. Seventeen species of arbuscular mycorrhizal fungi were recorded in four genera viz. Acaulospora (7 species, Glomus (5 species, Sclerocystis (3 species and Gigaspora (2 species.

  3. Arbuscular mycorrhiza increase artemisinin accumulation in Artemisia annua by higher expression of key biosynthesis genes via enhanced jasmonic acid levels.

    Science.gov (United States)

    Mandal, Shantanu; Upadhyay, Shivangi; Wajid, Saima; Ram, Mauji; Jain, Dharam Chand; Singh, Ved Pal; Abdin, Malik Zainul; Kapoor, Rupam

    2015-07-01

    It is becoming increasingly evident that the formation of arbuscular mycorrhiza (AM) enhances secondary metabolite production in shoots. Despite mounting evidence, relatively little is known about the underlying mechanisms. This study suggests that increase in artemisinin concentration in Artemisia annua colonized by Rhizophagus intraradices is due to altered trichome density as well as transcriptional patterns that are mediated via enhanced jasmonic acid (JA) levels. Mycorrhizal (M) plants had higher JA levels in leaf tissue that may be due to induction of an allene oxidase synthase gene (AOS), encoding one of the key enzymes for JA production. Non-mycorrhizal (NM) plants were exogenously supplied with a range of methyl jasmonic acid concentrations. When leaves of NM and M plants with similar levels of endogenous JA were compared, these matched closely in terms of shoot trichome density, artemisinin concentration, and transcript profile of artemisinin biosynthesis genes. Mycorrhization increased artemisinin levels by increasing glandular trichome density and transcriptional activation of artemisinin biosynthesis genes. Transcriptional analysis of some rate-limiting enzymes of mevalonate and methyl erythritol phosphate (MEP) pathways revealed that AM increases isoprenoids by induction of the MEP pathway. A decline in artemisinin concentration in shoots of NM and M plants treated with ibuprofen (an inhibitor of JA biosynthesis) further confirmed the implication of JA in the mechanism of artemisinin production.

  4. Subcellular Nutrient Element Localization and Enrichment in Ecto- and Arbuscular Mycorrhizas of Field-Grown Beech and Ash Trees Indicate Functional Differences

    Science.gov (United States)

    Seven, Jasmin; Polle, Andrea

    2014-01-01

    Mycorrhizas are the chief organ for plant mineral nutrient acquisition. In temperate, mixed forests, ash roots (Fraxinus excelsior) are colonized by arbuscular mycorrhizal fungi (AM) and beech roots (Fagus sylvatica) by ectomycorrhizal fungi (EcM). Knowledge on the functions of different mycorrhizal species that coexist in the same environment is scarce. The concentrations of nutrient elements in plant and fungal cells can inform on nutrient accessibility and interspecific differences of mycorrhizal life forms. Here, we hypothesized that mycorrhizal fungal species exhibit interspecific differences in mineral nutrient concentrations and that the differences correlate with the mineral nutrient concentrations of their associated root cells. Abundant mycorrhizal fungal species of mature beech and ash trees in a long-term undisturbed forest ecosystem were the EcM Lactarius subdulcis, Clavulina cristata and Cenococcum geophilum and the AM Glomus sp. Mineral nutrient subcellular localization and quantities of the mycorrhizas were analysed after non-aqueous sample preparation by electron dispersive X-ray transmission electron microscopy. Cenococcum geophilum contained the highest sulphur, Clavulina cristata the highest calcium levels, and Glomus, in which cations and P were generally high, exhibited the highest potassium levels. Lactarius subdulcis-associated root cells contained the highest phosphorus levels. The root cell concentrations of K, Mg and P were unrelated to those of the associated fungal structures, whereas S and Ca showed significant correlations between fungal and plant concentrations of those elements. Our results support profound interspecific differences for mineral nutrient acquisition among mycorrhizas formed by different fungal taxa. The lack of correlation between some plant and fungal nutrient element concentrations may reflect different retention of mineral nutrients in the fungal part of the symbiosis. High mineral concentrations, especially of

  5. Subcellular nutrient element localization and enrichment in ecto- and arbuscular mycorrhizas of field-grown beech and ash trees indicate functional differences.

    Directory of Open Access Journals (Sweden)

    Jasmin Seven

    Full Text Available Mycorrhizas are the chief organ for plant mineral nutrient acquisition. In temperate, mixed forests, ash roots (Fraxinus excelsior are colonized by arbuscular mycorrhizal fungi (AM and beech roots (Fagus sylvatica by ectomycorrhizal fungi (EcM. Knowledge on the functions of different mycorrhizal species that coexist in the same environment is scarce. The concentrations of nutrient elements in plant and fungal cells can inform on nutrient accessibility and interspecific differences of mycorrhizal life forms. Here, we hypothesized that mycorrhizal fungal species exhibit interspecific differences in mineral nutrient concentrations and that the differences correlate with the mineral nutrient concentrations of their associated root cells. Abundant mycorrhizal fungal species of mature beech and ash trees in a long-term undisturbed forest ecosystem were the EcM Lactarius subdulcis, Clavulina cristata and Cenococcum geophilum and the AM Glomus sp. Mineral nutrient subcellular localization and quantities of the mycorrhizas were analysed after non-aqueous sample preparation by electron dispersive X-ray transmission electron microscopy. Cenococcum geophilum contained the highest sulphur, Clavulina cristata the highest calcium levels, and Glomus, in which cations and P were generally high, exhibited the highest potassium levels. Lactarius subdulcis-associated root cells contained the highest phosphorus levels. The root cell concentrations of K, Mg and P were unrelated to those of the associated fungal structures, whereas S and Ca showed significant correlations between fungal and plant concentrations of those elements. Our results support profound interspecific differences for mineral nutrient acquisition among mycorrhizas formed by different fungal taxa. The lack of correlation between some plant and fungal nutrient element concentrations may reflect different retention of mineral nutrients in the fungal part of the symbiosis. High mineral concentrations

  6. Effects of mycorrhiza inoculation and different irrigation levels on yield, yield components and essential oil contents of fennel (Foeniculum vulgare Mill. and ajwain (Trachyspermum ammi L.

    Directory of Open Access Journals (Sweden)

    A Koocheki

    2016-05-01

    Full Text Available Introduction Fertilizers are the key components which provide plant nutrients' needs in recent years (Omid Jangir & Sing, 1996; Kapoor et al., 2007. In many cases, using chemical fertilizers has different negative environmental effects such as soil, water and air pollution, which increase environmental hazardous and production costs (Jangir & Sing, 1996; Kapoor et al., 2007. Biological activities are markedly enhanced by microbial interactions in the rhizosphere of plants (Kapoor et al., 2007. Many investigators have successfully used mycorrhiza to increase the availability of immobilized phosphate and thus minimize the use of mineral fertilizers. Arbuscular Mycorrhizal Fungi (AMF can better enable a plant to withstand environmental stresses such as drought and salinity. AMF interacts with pathogens and other rhizosphere inhabitants which affect plant health and nutrition. More importantly, mycorrhizal fungi are capable of dissolving weakly soluble soil minerals, especially phosphate, by releasing acids or increasing CO2 partial pressure (Gupta et al., 2002; Gosling et al., 2006; Kapoor et al., 2007. Therefore, they have the ability to enhance host plant uptake of relatively immobile nutrients particularly P, S and Zn. Limited water supply is also another major environmental constraint in the productivity of crop and medicinal plants. Moisture deficiency induces various physiological and metabolic responses such as stomatal closure, decline in growth rate and photosynthesis (Flexas and Medrano, 2002. The results of Baher et al. (2002 showed that greater soil water stress decreased plant height and total fresh and dry weight of Satureja hortensis. Materials and Methods In order to study the effects of mycorrhiza inoculation and different irrigation levels on the growth, quantitative and qualitative yield of fennel (Foeniculum vulgare Mill. and ajwain (Trachyspermum ammi L., a field experiment was conducted as factorial based on randomized

  7. Carbon dioxide concentration and nitrogen input affect the C and N storage pools in Amanita muscaria-Picea abies mycorrhizae.

    Science.gov (United States)

    Turnau, K; Berger, A; Loewe, A; Einig, W; Hampp, R; Chalot, M; Dizengremel, P; Kottke, I

    2001-02-01

    We studied the influence of elevated atmospheric CO2 concentration ([CO2]) on the vacuolar storage pool of nitrogen-containing compounds and on the glycogen pool in the hyphal sheath of Amanita muscaria (L. ex Fr.) Hooker-Picea abies L. Karst. mycorrhizae grown with two concentrations of ammonium in the substrate. Mycorrhizal seedlings were grown in petri dishes on agar containing 5.3 or 53 mg N l(-1) and exposed to 350 or 700 microl CO2 l(-1) for 5 or 7 weeks, respectively. Numbers and area of nitrogen-containing bodies in the vacuoles of the mycorrhizal fungus were determined by light microscopy linked to an image analysis system. The relative concentration of nitrogen in the vacuolar bodies was measured by electron energy loss spectroscopy (EELS). Glycogen stored in the cytosol was determined at the ultrastructural level by image analysis after staining the sections (PATAg test). Shoot dry weight, net photosynthesis and relative amounts of N in vacuolar bodies were greater at the higher N and CO2 concentrations. The numbers and areas of vacuolar N-containing bodies were significantly greater at the higher N concentration only at ambient [CO2]. In the same treatment the percentage of hyphae containing glycogen declined to nearly zero. We conclude that, in the high N/low [CO2] treatment, the mycorrhizal fungus had an insufficient carbohydrate supply, partly because of increased amino acid synthesis by the non-mycorrhizal rootlets. When [CO2] was increased, the equilibrium between storage of glycogen and N-containing compounds was reestablished.

  8. The sucrose transporter SlSUT2 from tomato interacts with brassinosteroid functioning and affects arbuscular mycorrhiza formation.

    Science.gov (United States)

    Bitterlich, Michael; Krügel, Undine; Boldt-Burisch, Katja; Franken, Philipp; Kühn, Christina

    2014-06-01

    Mycorrhizal plants benefit from the fungal partners by getting better access to soil nutrients. In exchange, the plant supplies carbohydrates to the fungus. The additional carbohydrate demand in mycorrhizal plants was shown to be balanced partially by higher CO2 assimilation and increased C metabolism in shoots and roots. In order to test the role of sucrose transport for fungal development in arbuscular mycorrhizal (AM) tomato, transgenic plants with down-regulated expression of three sucrose transporter genes were analysed. Plants that carried an antisense construct of SlSUT2 (SlSUT2as) repeatedly exhibited increased mycorrhizal colonization and the positive effect of plants to mycorrhiza was abolished. Grafting experiments between transgenic and wild-type rootstocks and scions indicated that mainly the root-specific function of SlSUT2 has an impact on colonization of tomato roots with the AM fungus. Localization of SISUT2 to the periarbuscular membrane indicates a role in back transport of sucrose from the periarbuscular matrix into the plant cell thereby affecting hyphal development. Screening of an expression library for SlSUT2-interacting proteins revealed interactions with candidates involved in brassinosteroid (BR) signaling or biosynthesis. Interaction of these candidates with SlSUT2 was confirmed by bimolecular fluorescence complementation. Tomato mutants defective in BR biosynthesis were analysed with respect to mycorrhizal symbiosis and showed indeed decreased mycorrhization. This finding suggests that BRs affect mycorrhizal infection and colonization. If the inhibitory effect of SlSUT2 on mycorrhizal growth involves components of BR synthesis and of the BR signaling pathway is discussed. © 2014 The Authors The Plant Journal © 2014 John Wiley & Sons Ltd.

  9. Toxicity of coal fly ash (CFA) and toxicological response of switchgrass in mycorrhiza-mediated CFA-soil admixtures.

    Science.gov (United States)

    Awoyemi, Olushola M; Dzantor, E Kudjo

    2017-10-01

    Increasing support for the use of Coal fly ash (CFA) in agriculture has necessitated a better understanding of the effects of the CFA in various cropping schemes. Experiments were conducted to assess mutagenic response of a mutant strain of Salmonella enterica serovar Typhimurium (TA100) to varying concentrations of CFA-water extracts, determine oxidative stress in switchgrass (Panicum virgatum L.) at varying levels of CFA-soil admixtures, and evaluate mycorrhiza-mediated modulation of oxidative stress responses of CFA-grown switchgrass. The TA100 exposed to 0%, 5%, 10%, 15%, 20% and 25% (w/v) CFA-water extracts elicited significant (p < 0.05) mutagenic responses at 20% and 25% extract levels but not below the 15% level. In greenhouse pot experiment, CFA-soil admixtures at 7.5% and 15% (w/w) significantly (p < 0.05) decreased the activities of superoxide dismutase (SOD) by 19.1% and 28.3% respectively, compared to control soil (0% w/w CFA/soil). Under the same conditions, activities of glutathione peroxidase (GPx) decreased by 75.9% and 66.9%. In contrast to the antioxidant enzyme activities, levels of malondialdehyde (MDA) an indicator of lipid peroxidation increased significantly (p < 0.05) by 30.49% and 38.38%. Inoculation of 7.5% and 15% CFA-soil admixtures with arbuscular mycorrhizal fungi (AMF), Rhizophaga clarus enhanced the activities of both SOD and GPx in the switchgrass, while it significantly (p < 0.05) reduced the levels of MDA. The study demonstrated that incorporation of CFA (at concentrations considered to be non-mutagenic against TA100) as soil amendment produced concentration-dependent oxidative stress responses in switchgrass; however, inoculation of the CFA-soil admixtures with AMF significantly modulated the oxidative stress responses. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Increasing phosphorus supply is not the mechanism by which arbuscular mycorrhiza increase attractiveness of bean (Vicia faba) to aphids.

    Science.gov (United States)

    Babikova, Zdenka; Gilbert, Lucy; Randall, Kate C; Bruce, Toby J A; Pickett, John A; Johnson, David

    2014-10-01

    Arbuscular mycorrhizal (AM) fungi, important plant mutualists, provide plants with nutrients such as phosphorus (P) in return for carbon. AM fungi also enhance the attractiveness of plants to aphids via effects on emissions of plant volatiles used in aphid host location. We tested whether increased P uptake by plants is the mechanism through which AM fungi alter the volatile profile of plants and aphid behavioural responses by manipulating the availability of P and AM fungi to broad beans (Vicia faba L.) in a multi-factorial design. If AM fungi affect plant volatiles only via increased P acquisition, we predicted that the emission of volatiles and the attractiveness of mycorrhizal beans to aphids would be similar to those of non-mycorrhizal beans supplied with additional P. AM fungi and P addition increased leaf P concentrations by 40 and 24%, respectively. The production of naphthalene was less in mycorrhizal plants, regardless of P addition. By contrast, production of (S)-linalool, (E)-caryophyllene and (R)-germacrene D was less in plants colonized by AM fungi but only in the absence of P additions. The attractiveness of plants to pea aphids (Acyrthosiphon pisum Harris) was positively affected by AM fungi and correlated with the extent of root colonization; however, attractiveness was neither affected by P treatment nor correlated with leaf P concentration. These findings suggest that increased P uptake is not the main mechanism by which mycorrhiza increase the attractiveness of plants to aphids. Instead, the mechanism is likely to operate via AM fungi-induced plant systemic signalling. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  11. The characterization of novel mycorrhiza-specific phosphate transporters from ¤Lycopersicon esculentum¤ and ¤Solanum tuberosum¤ uncovers functional redundancy in symbiotic phosphate transport in solanaceous species

    DEFF Research Database (Denmark)

    Nagy, F.; Karandashov, V.; Chague, W.

    2005-01-01

    [Proc. Natl Acad Sci. USA, 99 (2002) 13324], respectively, but not with StPT3, indicating that two non-orthologous mycorrhiza-responsive genes encoding Pi transporters are co-expressed in the Solanaceae. The cloned promoter regions from both genes, LePT4 and StPT4, exhibit a high degree of sequence...

  12. Arbuscular mycorrhiza enhanced arsenic resistance of both white clover (Trifolium repens Linn.) and ryegrass (Lolium perenne L.) plants in an arsenic-contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Dong Yan; Zhu Yongguan [Department of Soil Environmental Science, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China); Smith, F. Andrew [Soil and Land Systems, School of Earth and Environmental Sciences, Waite Campus, University of Adelaide, Adelaide, SA 5005 (Australia); Wang Youshan [Institute of Plant Nutrition and Resources, Beijing Academy of Agriculture and Forestry, Beijing 100089 (China); Chen Baodong [Department of Soil Environmental Science, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China)], E-mail: bdchen@rcees.ac.cn

    2008-09-15

    In a compartmented cultivation system, white clover (Trifolium repens Linn.) and ryegrass (Lolium perenne L.), with their roots freely intermingled, or separated by 37 {mu}m nylon mesh or plastic board, were grown together in an arsenic (As) contaminated soil. The influence of AM inoculation on plant growth, As uptake, phosphorus (P) nutrition, and plant competitions were investigated. Results showed that both plant species highly depended on mycorrhizas for surviving the As contamination. Mycorrhizal inoculation substantially improved plant P nutrition, and in contrast markedly decreased root to shoot As translocation and shoot As concentrations. It also showed that mycorrhizas affected the competition between the two co-existing plant species, preferentially benefiting the clover plants in term of nutrient acquisition and biomass production. Based on the present study, the role of AM fungi in plant adaptation to As contamination, and their potential use for ecological restoration of As contaminated soils are discussed. - Both white clover and ryegrass highly depend on the mycorrhizal associations for surviving heavy arsenic contamination.

  13. Interaction with mycorrhiza helper bacterium Streptomyces sp. AcH 505 modifies organisation of actin cytoskeleton in the ectomycorrhizal fungus Amanita muscaria (fly agaric).

    Science.gov (United States)

    Schrey, Silvia D; Salo, Vanamo; Raudaskoski, Marjatta; Hampp, Rüdiger; Nehls, Uwe; Tarkka, Mika T

    2007-08-01

    The actin cytoskeleton (AC) of fungal hyphae is a major determinant of hyphal shape and morphogenesis, implicated in controlling tip structure and secretory vesicle delivery. Hyphal growth of the ectomycorrhizal fungus Amanita muscaria and symbiosis formation with spruce are promoted by the mycorrhiza helper bacterium Streptomyces sp. AcH 505 (AcH 505). To investigate structural requirements of growth promotion, the effect of AcH 505 on A. muscaria hyphal morphology, AC and actin gene expression were studied. Hyphal diameter and mycelial density decreased during dual culture (DC), and indirect immunofluorescence microscopy revealed that the dense and polarised actin cap in hyphal tips of axenic A. muscaria changes to a loosened and dispersed structure in DC. Supplementation of growth medium with cell-free bacterial supernatant confirmed that reduction in hyphal diameter and AC changes occurred at the same stage of growth. Transcript levels of both actin genes isolated from A. muscaria remained unaltered, indicating that AC changes are regulated by reorganisation of the existing actin pool. In conclusion, the AC reorganisation appears to result in altered hyphal morphology and faster apical extension. The thus improved spreading of hyphae and increased probability to encounter plant roots highlights a mechanism behind the mycorrhiza helper effect.

  14. Growth and reproductive characteristics of the columnar cactus Stenocereus queretaroensis and their relationships with environmental factors and colonization by arbuscular mycorrhizae.

    Science.gov (United States)

    Pimienta-Barrios, Eulogio; Pimienta-Barrios, Enrique; Salas-Galván, Mariá Eugenia; Zañudo-Hernandez, Julia; Nobel, Park S

    2002-06-01

    Three natural populations of pitayo (Stenocereus queretaroensis (Weber) Buxbaum), a columnar arborescent cactus, were studied in their subtropical environments in western Mexico. All of the sites were characterized by shallow, nutrient-poor soils. Percentage of colonization by arbuscular mycorrhizae (AM) fungi, stem growth, fruit mass, and percentage germination were greater in S. queretaroensis at Autlan, Jalisco (AJ) than at Zacoalco de Torres, Jalisco (ZTJ) or Santa Rosa, Zacatecas (SRZ). The onset of root colonization by arbuscular mycorrhizae during the middle of the summer wet period preceded increases in stem extension rate and stem phosphorus concentration. Based on previous studies of effects of environmental factors on photosynthesis, climatic conditions were more favorable for photosynthesis at AJ than at SRZ and ZTJ, as indicated by the amount of summer rainfall, the amount of light, and the moderate air temperatures that prevailed during the fall and winter seasons. There was a significant positive correlation between stem growth and percentage of total root length colonized by arbuscules of AM fungi for S. queretaroensis at SRZ and AJ, but not at ZTJ. A negative significant correlation was observed between stem growth and maximal and minimal air temperatures at the three study sites. Stem growth was positively related to rainfall only at SRZ, and light was statistically related to stem growth only at ZTJ. Among sites, S. queretaroensis at AJ had the highest carbon gain and greatest AM colonization, creating physiological conditions that led to the highest stem growth, fruit mass and percentage of seed germination.

  15. Arum-type of arbuscular mycorrhizae, dark septate endophytes and Olpidium spp. in fine roots of container-grown seedlings of Sorbus torminalis (Rosaceae

    Directory of Open Access Journals (Sweden)

    Roman M. Bzdyk

    2016-06-01

    Full Text Available The aim of this study was to determine the mycorrhizal status of nursery seedlings of the wild service tree (Sorbus torminalis, which belongs to the Rosaceae family. Its mycorrhizal associations are still fragmentarily known, and data from the few existing studies indicate that it forms ectomycorrhizal symbiosis (ECM. We analyzed the degree of mycorrhizal colonization of thirty 2-year-old container-grown S. torminalis nursery seedlings, which belonged to three single-tree progenies. The roots were dominated by arbuscular mycorrhizae (AM, with the morphology of the Arum-type containing arbuscules, vesicles and hyphae; however, no ECM structures were found. The degree of root colonization of the analyzed seedlings by AM fungi was 83.6% and did not differ significantly between the three single-tree progenies. In addition to AM, structures of dark septate endophytes (0.7% and sporangia of Olpidium spp. (1.1% were found in wild service tree roots. In agreement with previous studies, we confirmed arbuscular mycorrhizae for S. torminalis. Moreover, this is the first report that roots of this Sorbus species show the Arum-type morphology of AM and are associated with Olpidium species.

  16. Mutualistic mycorrhiza in orchids: evidence from plant-fungus carbon and nitrogen transfers in the green-leaved terrestrial orchid Goodyera repens.

    Science.gov (United States)

    Cameron, Duncan D; Leake, Jonathan R; Read, David J

    2006-01-01

    The roles of mycorrhiza in facilitating the acquisition and transfer of carbon (C) and nitrogen (N) to adult orchids are poorly understood. Here, we employed isotopically labelled sources of C and N to investigate these processes in the green forest orchid, Goodyera repens. Fungus-to-orchid transfers of C and N were measured using mass spectrometry after supplying extraradical mycelial systems with double-labelled [13C-15N]glycine. Orchid-to-fungus C transfer was revealed and quantified by radioisotope imaging and liquid scintillation counting of extraradical mycelium following 14CO2 fixation by shoots. Both 13C and 15N were assimilated by the fungus and transferred to the roots and shoots of the orchid. Contrary to previous reports, considerable quantities (2.6% over 72 h) of fixed C were shown to be allocated to the extraradical mycelium of the fungus. This study demonstrates, for the first time, mutualism in orchid mycorrhiza, bidirectional transfer of C between a green orchid and its fungal symbiont, and a fungus-dependent pathway for organic N acquisition by an orchid.

  17. SymGRASS: a database of sugarcane orthologous genes involved in arbuscular mycorrhiza and root nodule symbiosis.

    Science.gov (United States)

    Belarmino, Luis Carlos; Silva, Roberta Lane de Oliveira; Cavalcanti, Nina da Mota Soares; Krezdorn, Nicolas; Kido, Ederson Akio; Horres, Ralf; Winter, Peter; Kahl, Günter; Benko-Iseppon, Ana Maria

    2013-01-01

    The rationale for gathering information from plants procuring nitrogen through symbiotic interactions controlled by a common genetic program for a sustainable biofuel production is the high energy demanding application of synthetic nitrogen fertilizers. We curated sequence information publicly available for the biofuel plant sugarcane, performed an analysis of the common SYM pathway known to control symbiosis in other plants, and provide results, sequences and literature links as an online database. Sugarcane sequences and informations were downloaded from the nucEST database, cleaned and trimmed with seqclean, assembled with TGICL plus translating mapping method, and annotated. The annotation is based on BLAST searches against a local formatted plant Uniprot90 generated with CD-HIT for functional assignment, rpsBLAST to CDD database for conserved domain analysis, and BLAST search to sorghum's for Gene Ontology (GO) assignment. Gene expression was normalized according the Unigene standard, presented as ESTs/100 kb. Protein sequences known in the SYM pathway were used as queries to search the SymGRASS sequence database. Additionally, antimicrobial peptides described in the PhytAMP database served as queries to retrieve and generate expression profiles of these defense genes in the libraries compared to the libraries obtained under symbiotic interactions. We describe the SymGRASS, a database of sugarcane orthologous genes involved in arbuscular mycorrhiza (AM) and root nodule (RN) symbiosis. The database aggregates knowledge about sequences, tissues, organ, developmental stages and experimental conditions, and provides annotation and level of gene expression for sugarcane transcripts and SYM orthologous genes in sugarcane through a web interface. Several candidate genes were found for all nodes in the pathway, and interestingly a set of symbiosis specific genes was found. The knowledge integrated in SymGRASS may guide studies on molecular, cellular and physiological

  18. IMPACT OF BRACHIARIA, ARBUSCULAR MYCORRHIZA, AND POTASSIUM ENRICHED RICE STRAW COMPOST ON ALUMINIUM, POTASSIUM AND STABILITY OF ACID SOIL AGGREGATES

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    Bariot Hafif

    2013-04-01

    Full Text Available Acid soil is commonly grown with cassava, which in general, tolerate low soil  fertility and aluminum (Al toxicity. However, without any improvement efforts such soil will become worse. Intercropping cassava with Brachiaria decumbens (BD which adapts to acid soil and tolerates low fertility soils as well as application of arbuscular mycorrhiza (AM and organic matters are among the important efforts to rehabilitate this soil. The experiment was conducted to  examine the impact of BD, AM, and potassium (K enriched rice straw compost on exchangeable Al, available K, and stability of soil aggregates. Experiment was arranged in a completely randomized design with three factors and three replications. The first factor was BD as cassava intercropping, the second factor was AM, and the third factor was 2 t ha-1 rice straw compost enriched with 0 kg, 50 kg, 100 kg, and 200 kg KCl ha-1. Brick pots (1 m length x 1 m width x 0.45 m depth filled with Kanhapludult soil was used for growing cassava in which row of BD was planted at 60 cm from cassava stem. K-enriched rice straw compost and AM (10 g per stem were applied around cassava stem at 2 and 12 days after planting, respectively. BD was cut every 30 days and the cutting was returned to the soil. Soil exchangeable Al was analyzed at 0, 3, 6 and 9 months after planting (MAP, while Al and K contents as well as aggregate stability were measured at 6 MAP. The results showed that planting BD decreased 33% exchangeable Al, which means that the root exudates of this grass was effective in detoxifying Al3+. Treatment of BD and/or in combination with AM was effective in preserving K added to the soil, increasing total polysaccharides, and improving soil aggregate stability. This indicated that planting BD and applying AM and Kenriched rice straw compost improved acid soil fertility, and therefore can be recommended in cassava cultivation.

  19. Large scale transcriptome analysis reveals interplay between development of forest trees and a beneficial mycorrhiza helper bacterium.

    Science.gov (United States)

    Kurth, Florence; Feldhahn, Lasse; Bönn, Markus; Herrmann, Sylvie; Buscot, François; Tarkka, Mika T

    2015-09-02

    Pedunculate oak, Quercus robur is an abundant forest tree species that hosts a large and diverse community of beneficial ectomycorrhizal fungi (EMFs), whereby ectomycorrhiza (EM) formation is stimulated by mycorrhiza helper bacteria such as Streptomyces sp. AcH 505. Oaks typically grow rhythmically, with alternating root flushes (RFs) and shoot flushes (SFs). We explored the poorly understood mechanisms by which oaks integrate signals induced by their beneficial microbes and endogenous rhythmic growth at the level of gene expression. To this end, we compared transcript profiles of oak microcuttings at RF and SF during interactions with AcH 505 alone and in combination with the basidiomycetous EMF Piloderma croceum. The local root and distal leaf responses to the microorganisms differed substantially. More genes involved in the recognition of bacteria and fungi, defence and cell wall remodelling related transcription factors (TFs) were differentially expressed in the roots than in the leaves of oaks. In addition, interaction with AcH 505 and P. croceum affected the expression of a higher number of genes during SF than during RF, including AcH 505 elicited defence response, which was attenuated by co-inoculation with P. croceum in the roots during SF. Genes encoding leucine-rich receptor-like kinases (LRR-RLKs) and proteins (LRR-RLPs), LRR containing defence response regulators, TFs from bZIP, ERF and WRKY families, xyloglucan cell wall transglycolases/hydrolases and exordium proteins were differentially expressed in both roots and leaves of plants treated with AcH 505. Only few genes, including specific RLKs and TFs, were induced in both AcH 505 and co-inoculation treatments. Treatment with AcH 505 induces and maintains the expression levels of signalling genes encoding candidate receptor protein kinases and TFs and leads to differential expression of cell wall modification related genes in pedunculate oak microcuttings. Local gene expression response to AcH 505

  20. Novel root-fungus symbiosis in Ericaceae: sheathed ericoid mycorrhiza formed by a hitherto undescribed basidiomycete with affinities to Trechisporales.

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    Martin Vohník

    Full Text Available Ericaceae (the heath family are widely distributed calcifuges inhabiting soils with inherently poor nutrient status. Ericaceae overcome nutrient limitation through symbiosis with ericoid mycorrhizal (ErM fungi that mobilize nutrients complexed in recalcitrant organic matter. At present, recognized ErM fungi include a narrow taxonomic range within the Ascomycota, and the Sebacinales, basal Hymenomycetes with unclamped hyphae and imperforate parenthesomes. Here we describe a novel type of basidiomycetous ErM symbiosis, termed 'sheathed ericoid mycorrhiza', discovered in two habitats in mid-Norway as a co-dominant mycorrhizal symbiosis in Vaccinium spp. The basidiomycete forming sheathed ErM possesses clamped hyphae with perforate parenthesomes, produces 1- to 3-layer sheaths around terminal parts of hair roots and colonizes their rhizodermis intracellularly forming hyphal coils typical for ErM symbiosis. Two basidiomycetous isolates were obtained from sheathed ErM and molecular and phylogenetic tools were used to determine their identity; they were also examined for the ability to form sheathed ErM and lignocellulolytic potential. Surprisingly, ITS rDNA of both conspecific isolates failed to amplify with the most commonly used primer pairs, including ITS1 and ITS1F + ITS4. Phylogenetic analysis of nuclear LSU, SSU and 5.8S rDNA indicates that the basidiomycete occupies a long branch residing in the proximity of Trechisporales and Hymenochaetales, but lacks a clear sequence relationship (>90% similarity to fungi currently placed in these orders. The basidiomycete formed the characteristic sheathed ErM symbiosis and enhanced growth of Vaccinium spp. in vitro, and degraded a recalcitrant aromatic substrate that was left unaltered by common ErM ascomycetes. Our findings provide coherent evidence that this hitherto undescribed basidiomycete forms a morphologically distinct ErM symbiosis that may occur at significant levels under natural conditions, yet

  1. Influence of roots and mycorrhiza on the internal nitrogen cycle in an organic forest soil ­revealed by a 15N tracing experiment

    Science.gov (United States)

    Holz, M.; Rutting, T.; Klemedtsson, L.; Kuzyakov, Y.

    2014-12-01

    The cycle of nitrogen in soil is complex, consisting of many simultaneous occurring transformation processes. So far, microorganisms have been thought to govern N cycling in soil. Nevertheless, plant roots and their associated mycorrhizal symbionts may exert control on N turnover for example by input of labile C to soil. However, studies investigating the effect of roots on gross N turnover rates are scarce. We conducted a 15N tracer study under field conditions to reveal the effect of plants on soil N cycle. The experiment includes three treatments: (a) control, (b) excluding roots and (c) excluding roots + mycorrhiza. On the study site, exclusion of roots + mycorrhiza has previously been shown to increase N2O emissions which indicate that plants affect internal N cycling. 15NH4NO3 and NH415NO3 were given to the soil and traced for a period of 10 days. Gross N turnover rates were determined applying a numerical 15N tracing model. Results on N turnover rates showed that roots and their fungal symbionts increased N cycling probably by input of labile C to soil which may results in an activation of the microbial biomass. While gross N mineralization increased by 270 and 313 % compared to the treatment excluding roots + mycorrhiza, NH4+ immobilization increased by 402 and 489 %. Differences in ammonium and nitrate immobilization further indicated that ammonium was the preferred N source for roots and microorganisms. While ammonium availability decreased with trenching (0.59 compared to -0.47 and -0.96 μg N g-1 d-1), the opposite was true for nitrate (0.50 compared to 2.08 and 2.18 μg N g-1 d-1), explaining the increased N2O emissions which were likely caused by denitrification. Further, plants increased dissimilarity nitrate reduction to ammonium (DNRA) and affected autotrophic nitrification probably by the release of nitrification inhibitors and by influencing ammonium availability. We conclude that plants and their mycorrhizal symbionts actively control N cycling

  2. Co-Inoculation Effects of Thiobacillus thiooxidans Bacteria and Mycorrhiza (Glomus spp. on Maize Nutrition at Different Levels of Sulfur

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    A. Gholami

    2016-02-01

    was performed on all experimental data and means were compared using the least Significant Differences (LSD test with SAS software. The significance level was p>0.05 unless stated otherwise. Results and Discussion: Results showed sulfur application increased significantly the amount of S, P, N, Fe, Zn, shoot dry weight and leaf chlorophyll of maize. With increasing Sulfur, sulfur concentration in plant shoot increased with linear trend. The highest S concentration was obtained with 200 mg.kg-1 S and the lowest amount was obtained from control plots. Applications of 50, 100, 150 and 200 mg.kg-1 S increased P content about 0.45, 3.91, 4.74 and 5.56 %, respectively. The highest N contentwas obtained with 100 mg.kg-1 S. The thiobacillus significantly increased P, Fe, Zn anddecreased root colonization and soil pH compared to control. Thiobacillus bacteria increased shoot P only with application of 100 mg.kg-1 S. Mycorrhizal inoculation increased the amount of N, P, S, Fe, Zn, shoot dry weight and root colonization. Inoculation with G.intra and G.mosseae increased shoot P content about 4.18 and 3.34% in comparison with the control plots. Single or combination of sulfur and thiobacillus had a negative impact on the root colonization. Based on the results it seems that sulfur, thiobacillus and mycorrhiza in alkaline soils improved crops nutrition and growth. S application and thiobacillus interaction on S concentration of maize shoot were significant. In condition of 0 or 50 mg.kg-1 S application, inoculation of thiobacillus is recommended. Also, the effects of mycorrhiza on P shoot was significant with no application of S.

  3. Effect of mycorrhiza and phosphorus content in nutrient solution on the yield and nutritional status of tomato plants grown on rockwool or coconut coir

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    Iwona Kowalska

    2015-03-01

    Full Text Available Effects of P level in nutrient solution and the colonization of roots by arbuscular mycorrhizal fungi (AMF on P uptake by tomato plants, their nutritional status, yield and quality of fruits were studied. Plants were grown on rockwool or coconut coir. Inoculation by a mixture of several AMF species was performed three times during the growing period. The mycorrhizal frequency in roots inoculated with AMF amounted to 35.79 – 50.82%. The highest level of mycorrhiza was found in plants receiving nutrient solution with a lower concentration of P. Among the experimental factors, only P level influenced the fruit yield, being higher from plants receiving a nutrient solution with a higher P level. A higher concentration of P in nutrient solution imposed better nutritional status of plants. Higher contents of ascorbic acid and total soluble sugars were found in fruits collected from inoculated plants, grown on rockwool.

  4. Changes in host-mycorrhiza relationships revealed by stable isotopes after naturally-induced thinning of the stand: case study on Tuber aestivum.

    Science.gov (United States)

    Gavrichkova, Olga; Lauteri, Marco; Ciolfi, Marco; Chiocchini, Francesca; Paris, Pierluigi; Pisanelli, Andrea; Portarena, Silvia; Brugnoli, Enrico

    2016-04-01

    Terrestrial plants overcome nutrients and water limitations by forming mutualistic associations with mycorrhizal fungi. Fungi, in return, take advantage from the carbohydrates supplied by the host. Some mycorrhizal fruit bodies, like that of Tuber spp., have a peculiar gastronomic value with many efforts being undertaken to predict and enhance their productivity. However, many issues of truffle-producing mycorrhizal ecology are still poorly understood, in particular optimal conditions favoring fruit formation, potential host plants and host-mycorrhiza relationships. In this study, we tested the applicability of stable isotope measurements under natural abundance to identify the plants which likely host the mycorrhiza of Tuber aestivum and to characterize host-mycorrhizal nutrient, water and carbohydrate exchange under plant natural growing conditions and with the change of the forest cover after naturally occurred thinning. For these purposes, sampling of the fruit bodies of T. aestivum was performed during the growing season 2011 in a mixed broadleaved-coniferous forest in central Italy (initially the site was a manmade pine plantation). Nine truffle-producing parcels were identified with five being composed of the original Pinus pinaster -dominated vegetation and four in which pine was replaced by broadleaf species after both wind-induced thinning and natural dieback of pine trees. Seasonal variation of δ13C, δ15N and δ18O were analyzed in the fungal material, in the surrounding soil and in the plant material of the potential host species (xylem water in the trunk, branches and leaves, recently assimilated carbohydrates in phloem and leaves). The results showed a possibility of the identification of the mycorrhizal host species applying isotope analyses, with mycorrhiza receiving most part of the carbohydrates from the pine in pine-dominated parcels. Interestingly, in thinned parcels, the truffle bodies maintained isotope composition similar to bodies gathered

  5. Local and systemic mycorrhiza-induced protection against the ectoparasitic nematode Xiphinema index involves priming of defence gene responses in grapevine

    Science.gov (United States)

    Hao, Zhipeng; Fayolle, Léon; van Tuinen, Diederik; Chatagnier, Odile; Gianinazzi, Silvio; Gianinazzi-Pearson, Vivienne

    2012-01-01

    The ectoparasitic dagger nematode (Xiphinema index), vector of Grapevine fanleaf virus (GFLV), provokes gall formation and can cause severe damage to the root system of grapevines. Mycorrhiza formation by Glomus (syn. Rhizophagus) intraradices BEG141 reduced both gall formation on roots of the grapevine rootstock SO4 (Vitis berlandieri×V. riparia) and nematode number in the surrounding soil. Suppressive effects increased with time and were greater when the nematode was post-inoculated rather than co-inoculated with the arbuscular mycorrhizal (AM) fungus. Using a split-root system, decreased X. index development was shown in mycorrhizal and non-mycorrhizal parts of mycorrhizal root systems, indicating that both local and systemic induced bioprotection mechanisms were active against the ectoparasitic nematode. Expression analyses of ESTs (expressed sequence tags) generated in an SSH (subtractive suppressive hybridization) library, representing plant genes up-regulated during mycorrhiza-induced control of X. index, and of described grapevine defence genes showed activation of chitinase 1b, pathogenesis-related 10, glutathione S-transferase, stilbene synthase 1, 5-enolpyruvyl shikimate-3-phosphate synthase, and a heat shock proein 70-interacting protein in association with the observed local and/or systemic induced bioprotection against the nematode. Overall, the data suggest priming of grapevine defence responses by the AM fungus and transmission of a plant-mediated signal to non-mycorrhizal tissues. Grapevine gene responses during AM-induced local and systemic bioprotection against X. index point to biological processes that are related either to direct effects on the nematode or to protection against nematode-imposed stress to maintain root tissue integrity. PMID:22407649

  6. PARTITIONING THE RELATIVE INFLUENCE OF SOIL N, MYCORRHIZAE, AND FOLIAR N UPTAKE ON FOLIAR δ15N PATTERNS: CAN WE DETECT FOLIAR UPTAKE OF REACTIVE N?

    Science.gov (United States)

    Vallano, D.; Sparks, J. P.

    2009-12-01

    Vegetation is an important sink for atmospheric reactive N in N-limited systems and may be capable of incorporating reactive N compounds directly into leaves through the foliar uptake pathway. A proxy for atmospheric reactive N entering vegetation would be useful to estimate the impact of direct foliar N uptake on plant metabolism. Natural abundance foliar N isotopic composition (δ15N) is a practical tool for this purpose because plant-available N sources often have different isotopic compositions. Current understanding of foliar δ15N suggests these values primarily represent the integration of soil δ15N, direct foliar N uptake, mycorrhizal fractionation, and within-plant fractionations. Using a potted plant mesocosm system, we estimated the influence of mycorrhizae on foliar δ15N patterns in red maple (Acer rubrum) seedlings along an N deposition gradient in New York State. We found that mycorrhizal associations altered foliar δ15N in red maple seedlings from 0.03 - 1.01‰ across sites. Along the same temporal and spatial scales, we examined the influence of soil δ15N, foliar N uptake, and mycorrhizae on foliar δ15N in adult stands of American beech (Fagus grandifolia), black birch (Betula lenta), red maple (A. rubrum), and red oak (Quercus rubra). Using multiple regression models, atmospheric NO2 concentration explained 0%, 69%, 23%, and 45% of the residual variation in foliar δ15N remaining in American beech, red maple, red oak, and black birch, respectively, after accounting for soil δ15N. Our results suggest that foliar δ15N may be used to estimate pollution-derived atmospheric reactive N entering vegetation via the foliar N uptake pathway.

  7. External hyphae of Rhizophagus irregularis DAOM 197198 are less sensitive to low pH than roots in arbuscular mycorrhizae: evidence from axenic culture system.

    Science.gov (United States)

    Wang, Ning; Feng, Zengwei; Zhou, Yang; Zhu, Honghui; Yao, Qing

    2017-10-01

    The growth of plant roots and arbuscular mycorrhizal fungi (AMF) can be inhibited by low pH; however, it is largely unknown which is more sensitive to low pH. This study aimed to compare the physiological and molecular responses of external hyphae (EH) and roots to low pH in terms of growth, development and functioning. We established AM symbiosis in a two-compartmented system (root compartment, RC; hyphal compartment, HC) using AMF and transformed hairy roots and exposed them to pH 6.5 and/or pH 4.5. The results showed that pH 4.5 significantly decreased root cell viability, while EH at pH 6.5 attenuated the effect. In either RC or HC, pH 4.5 reduced biomass, P content, colonization, ALP activity in roots, and ALP activity and polyphosphate accumulation in EH. GintPT expression in EH was inhibited by pH 4.5 in HC but not in RC. The expression of mycorrhiza-responsive LePTs was significantly reduced by the lower colonization due to decreased pH in either RC or HC, while the expression of non-mycorrhiza-responsive LePTs was not affected. Variation partitioning analysis indicated that EH was less sensitive to low pH than roots. The interactions between roots and EH under low pH stress merit further investigation. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

  8. Local and systemic mycorrhiza-induced protection against the ectoparasitic nematode Xiphinema index involves priming of defence gene responses in grapevine.

    Science.gov (United States)

    Hao, Zhipeng; Fayolle, Léon; van Tuinen, Diederik; Chatagnier, Odile; Li, Xiaolin; Gianinazzi, Silvio; Gianinazzi-Pearson, Vivienne

    2012-06-01

    The ectoparasitic dagger nematode (Xiphinema index), vector of Grapevine fanleaf virus (GFLV), provokes gall formation and can cause severe damage to the root system of grapevines. Mycorrhiza formation by Glomus (syn. Rhizophagus) intraradices BEG141 reduced both gall formation on roots of the grapevine rootstock SO4 (Vitis berlandieri×V. riparia) and nematode number in the surrounding soil. Suppressive effects increased with time and were greater when the nematode was post-inoculated rather than co-inoculated with the arbuscular mycorrhizal (AM) fungus. Using a split-root system, decreased X. index development was shown in mycorrhizal and non-mycorrhizal parts of mycorrhizal root systems, indicating that both local and systemic induced bioprotection mechanisms were active against the ectoparasitic nematode. Expression analyses of ESTs (expressed sequence tags) generated in an SSH (subtractive suppressive hybridization) library, representing plant genes up-regulated during mycorrhiza-induced control of X. index, and of described grapevine defence genes showed activation of chitinase 1b, pathogenesis-related 10, glutathione S-transferase, stilbene synthase 1, 5-enolpyruvyl shikimate-3-phosphate synthase, and a heat shock proein 70-interacting protein in association with the observed local and/or systemic induced bioprotection against the nematode. Overall, the data suggest priming of grapevine defence responses by the AM fungus and transmission of a plant-mediated signal to non-mycorrhizal tissues. Grapevine gene responses during AM-induced local and systemic bioprotection against X. index point to biological processes that are related either to direct effects on the nematode or to protection against nematode-imposed stress to maintain root tissue integrity.

  9. Carbon cost of the fungal symbiont relative to net leaf P accumulation in a split-root VA mycorrhizal symbiosis. [Poncirus trifoliata L. Raf. x Citrus sinensis L. Osbeck; Glomus intraradices Schenk and Smith

    Energy Technology Data Exchange (ETDEWEB)

    Douds, D.D. Jr.; Johnson, C.R.; Koch, K.E. (Univ. of Florida, Gainesville (USA))

    1988-02-01

    Translocation of {sup 14}C-photosynthates to mycorrhizal (++), half mycorrhizal (0+), and nonmycorrhizal (00) split-root systems was compared to P accumulation in leaves of the host plant. Carrizo citrange seedlings (Poncirus trifoliata (L.) Raf. {times} Citrus sinensis (L.) Osbeck) were inoculated with the vesicular-arbuscular mycorrhizal fungus Glomus intraradices Schenck and Smith. Plants were exposed to {sup 14}CO{sub 2} for 10 minutes and ambient air for 2 hours. Three to 4% of recently labeled photosynthate was allocated to metabolism of the mycorrhiza in each inoculated root half independent of shoot P concentration, growth response, and whether one or both root halves were colonized. Nonmycorrhizal roots respired more of the label translocated to them than did mycorrhizal roots. Label recovered in the potting medium due to exudation or transport into extraradical hyphae was 5 to 6 times greater for (++) versus (00) plants. In low nutrient media, roots of (0+) and (++) plants transported more P to leaves per root weight than roots of (00) plants. However, when C translocated to roots utilized for respiration, exudation, etc., as well as growth is considered, (00) plant roots were at least as efficient at P uptake (benefit) per C utilized (cost) as (0+) and (++) plants. Root systems of (++) plants did not supply more P to leaves than (0+) plants in higher nutrient media, yet they still allocated twice the {sup 14}C-photosynthate to the mycorrhiza as did (0+) root systems.

  10. Effect of simultaneous application of mycorrhiza with compost, vermicompost and sulfural geranole on some quantitative and qualitative characteristics of sesame (Sesamum indicum L. in a low input cropping system

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    P rezvani moghaddam

    2016-03-01

    Full Text Available Introduction In recent years, by increasing human knowledge and using different technology on food production, human concerns have increased on safety of food products especially medicinal crops. In order to achieve healthy food production, application of ecological inputs such as organic and biological fertilizers are inevitable. Organic fertilizers are fertilizer compounds that contain one or more kinds of organic matter. They can improve the soil ability to hold water and nutrients. They create a beneficial environment for earthworms and microbial organisms that break the soil down into rich, fine humus (Motta & Magggiore, 2013. Compost is organic matter that has been decomposed and recycled as a fertilizer and soil amendment. Compost can greatly enhance the physical structure of soil. The addition of compost may provide greater drought resistance and more efficient water utilization. Vermicompost is the final product of composting organic material using different types of worms, such as red wigglers or earthworms, to create a homogenized blend of decomposed vegetable and food waste, bedding materials and manure. Vermicompost helps store nutrients and keeps them safe from leaching and irrigation, functioning to balance hormones within plant physiology, and adding beneficial biology to soil (Raja Sekar & Karmegan, 2010. Mycorrhiza arbuscular fungi are other coexist microorganisms that improves soil fertility, nutrients cycling and agroecosystem health. Mycorrhizal fungi are the most abundant organisms in agricultural soils. Many researchers have pointed to the positive roles of mycorrhizal fungi on plants growth characteristics. Despite of many researches on the effect of organic and biological fertilizers on different crops, information on the effects of these fertilizers for many medicinal plants is scarce, therefore, in this study the effect of simultaneous application of mycorrhiza with compost, vermicompost and sulfural geranole on some

  11. Influence of VA-mycorrhiza on heavy metal uptake of oat (Avena sativa L.) from soils differing in heavy metal contamination; Einfluss der VA-Mykorrhiza auf die Schwermetallaufnahme von Hafer (Avena sativa L.) in Abhaengigkeit vom Kontaminationsgrad der Boeden

    Energy Technology Data Exchange (ETDEWEB)

    Loth, F.G. [Giessen Univ. (Germany). Inst. fuer Pflanzenernaehrung; Hoefner, W. [Giessen Univ. (Germany). Inst. fuer Pflanzenernaehrung

    1995-12-31

    The heavy metal uptake of mycorrhizal oat-plants (Avena sativa L.) was evaluated in pot experiments with two soils differing in heavy meatl accumulation. The effect of the fungal isolates on the uptake of the immobile metals Zn and Cu differed between the two soils: In the soil `Kleinlinden` mycorrhizal colonization increased heavy metal uptake by up to 37%. In the highly contaminated soil `Muenchen`, mycorrhizal infection lead to a higher uptake (max. 59%) in roots but to a reduced translocation to the aerial plant fractions. The higher uptake of Zn and Cu into the roots was related to the higher heavy metal concentrations in this soil. The Cd uptake showed no difference between the two soils, but was increased in the roots by VAM together with a lower translocation into the shoots. VAM-formation changed the root architecture by increacing the specific root length (m g{sup -1} root dry matter) and the total root length (km per pot). This increased absorbing surface of the roots was a major, but not the only cause for the differences in heavy metal uptake. (orig.) [Deutsch] Die Schwermetallaufnahme mykorrhizierter Hafer-Pflanzen (Avena sativa L.) wurde im Gefaessversuch mit zwei Boeden unterschiedlicher Belastung evaluiert. Der Einfluss der VAM-Pilzisolate auf die Aufnahme der relativ immobilen Metalle Zn und Cu war stark abhaengig vom eingesetzten Boden: Im Versuch mit dem gering belasteten Kleinlindener Boden wurde die Schwermetallaufnahme in den Spross bis zu 37% gesteigert. Die Beimpfung der Pflanzen auf dem hochkontaminierten Boden aus Muenchen fuehrte dagegen zu hoeheren Aufnahmeraten (bis zu 59%) in der Wurzel bei verringerter Translokation in die oberirdischen Pflanzenteile. Das mobile Schwermetall Cd wurde aus beiden Substraten verstaerkt in die infizierten Wurzeln aufgenommen und in vermindertem Mass in den Spross geleitet. Die mykorrhizainduzierte Vergroesserung der speziellen (m g{sup -1} Wurzel-TM) und der absoluten (km pro Gefaess) Wurzellaenge war in

  12. Effects of Pseudomonas putida and Glomusintraradices Inoculations on Morphological and Biochemical Traitsin Trigonellafoenum-graecum L.

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    simin irankhah

    2017-02-01

    Full Text Available Introduction: Fenugreek (Trigonellafoenum-graecum L. is a traditional medicinal plant belonging to the legume family Fabaceae. Diverse groups of microorganisms are symbiotic with Fenugreek roots system. This integration leads to significant increases in the development and production by increasing nitrogen fixation, phytohormones production, siderophores and phosphate solubilization. Plant growth-promoting bacteria increase plant growth byimproving nutrientuptake and phytohormones production. In addition, the beneficial effect of these bacteria could be due totheirinteractionwithArbuscularMycorrhizal fungi(VAM. Drought is one of the major limiting factors for crop production in many parts of the world including Iran. Symbiotic microorganisms can enhance plant tolerance to drought. This experiment was carried out to investigate the effect of Vesicular ArbuscularMycorrhiza (VAM and Plant Growth Promoting Rhizobacteria (PGPR on morphological and biochemical characteristics of Fenugreek in drought stress conditions. Materials and Methods: The experiment was carried out in completely random design with 3 replications.There were four treatments including inoculation with Pseudomonas putida, inoculation with Glomusintraradices, combined association of Pseudomonas putida and Glomusintraradices and untreated as a check under drought stress (40% of field capacity and non-stress conditions (80% of field capacity. In this experiment fiveseeds were sowninplastic pots. Before sowing, seeds were inoculated with microorganisms. In order to inoculation ofseed with Mycorrhizal fungi, for each kilogram of soil, 100 grams of powder containing 10 to 15 thousand spores of fungal soil (produced by the biotech company Toos was added to three centimeters of soil in the pot. For seed inoculation with Plant Growth Promoting Rhizobacteria, the growth curve of the bacteria was drawn at first and then the best time for the growth of bacteria was determined. The bacteria at

  13. Mycorrhiza nuttig mits ...

    NARCIS (Netherlands)

    Baar, J.; Olijnsma, T.W.

    2006-01-01

    Bij het toepassen van mycorrhizaschimmels wordt vaak gekeken naar het gunstigste effect van de schimmel zelf. Uit recent onderzoek van PPO blijkt echter dan het effect van schimmelpreparaten vooral afhankelijk is van bodemeigenschappen en de samenstelling van de bodem. Ook de plant zelf heeft

  14. Plants without arbuscular mycorrhizae

    Science.gov (United States)

    P is second to N as the most limiting element for plant growth. Plants have evolved a number of effective strategies to acquire P and grow in a P-limited environment. Physiological, biochemical, and molecular studies of P-deficiency adaptations that occur in non-mycorrhizal species have provided str...

  15. Micorrizas arbusculares en plantines de Alnus acuminata (Betulaceae inoculados con Glomus intraradices (Glomaceae Arbuscular mycorrhizas in Alnus acuminata (Betulaceae seedlings inoculated with Glomus intraradices (Glomaceae

    Directory of Open Access Journals (Sweden)

    Alejandra Becerra

    Full Text Available En este trabajo se cita y describe por primera vez la asociación de Alnus acuminata Kunth «aliso del cerro» con el hongo formador de micorrizas arbusculares (MA Glomus intraradices Schenk & Smith. En un bioensayo en invernadero, se inocularon plantines de A. acuminata con fragmentos radicales de Medicago sativa L. colonizados por G. intraradices . Se describe la colonización MA y el tipo anatómico Arum . Se establece la funcionalidad de la simbiosis por la presencia de arbúsculos en las células corticales de la raíz.This work described for the first time the arbuscular mycorrhiza (AM development in A. acuminata Kunth «andean alder» with G. intraradices Schenk & Smith. Seedlings of A. acuminata were inoculated with root fragments of Medicago sativa L. colonized by G. intraradices in a greenhouse. The Arum -type and AM colonization are described in A. acuminata seedlings. The presence of arbuscules in A. acuminata cortical cells define a functional symbiosis.

  16. Auxofuran, a Novel Metabolite That Stimulates the Growth of Fly Agaric, Is Produced by the Mycorrhiza Helper Bacterium Streptomyces Strain AcH 505†

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    Riedlinger, Julia; Schrey, Silvia D.; Tarkka, Mika T.; Hampp, Rüdiger; Kapur, Manmohan; Fiedler, Hans-Peter

    2006-01-01

    The mycorrhiza helper bacterium Streptomyces strain AcH 505 improves mycelial growth of ectomycorrhizal fungi and formation of ectomycorrhizas between Amanita muscaria and spruce but suppresses the growth of plant-pathogenic fungi, suggesting that it produces both fungal growth-stimulating and -suppressing compounds. The dominant fungal-growth-promoting substance produced by strain AcH 505, auxofuran, was isolated, and its effect on the levels of gene expression of A. muscaria was investigated. Auxofuran and its synthetic analogue 7-dehydroxy-auxofuran were most effective at a concentration of 15 μM, and application of these compounds led to increased lipid metabolism-related gene expression. Cocultivation of strain AcH 505 and A. muscaria stimulated auxofuran production by the streptomycete. The antifungal substances produced by strain AcH 505 were identified as the antibiotics WS-5995 B and C. WS-5995 B completely blocked mycelial growth at a concentration of 60 μM and caused a cell stress-related gene expression response in A. muscaria. Characterization of these compounds provides the foundation for molecular analysis of the fungus-bacterium interaction in the ectomycorrhizal symbiosis between fly agaric and spruce. PMID:16672502

  17. Auxofuran, a novel metabolite that stimulates the growth of fly agaric, is produced by the mycorrhiza helper bacterium Streptomyces strain AcH 505.

    Science.gov (United States)

    Riedlinger, Julia; Schrey, Silvia D; Tarkka, Mika T; Hampp, Rüdiger; Kapur, Manmohan; Fiedler, Hans-Peter

    2006-05-01

    The mycorrhiza helper bacterium Streptomyces strain AcH 505 improves mycelial growth of ectomycorrhizal fungi and formation of ectomycorrhizas between Amanita muscaria and spruce but suppresses the growth of plant-pathogenic fungi, suggesting that it produces both fungal growth-stimulating and -suppressing compounds. The dominant fungal-growth-promoting substance produced by strain AcH 505, auxofuran, was isolated, and its effect on the levels of gene expression of A. muscaria was investigated. Auxofuran and its synthetic analogue 7-dehydroxy-auxofuran were most effective at a concentration of 15 microM, and application of these compounds led to increased lipid metabolism-related gene expression. Cocultivation of strain AcH 505 and A. muscaria stimulated auxofuran production by the streptomycete. The antifungal substances produced by strain AcH 505 were identified as the antibiotics WS-5995 B and C. WS-5995 B completely blocked mycelial growth at a concentration of 60 microM and caused a cell stress-related gene expression response in A. muscaria. Characterization of these compounds provides the foundation for molecular analysis of the fungus-bacterium interaction in the ectomycorrhizal symbiosis between fly agaric and spruce.

  18. Molecular and morpho-anatomical description of mycorrhizas of Lactarius rimosellus on Quercus sp., with ethnomycological notes on Lactarius in Guatemala.

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    Comandini, Ornella; Erős-Honti, Zsolt; Jakucs, Erzsébet; Arzú, Roberto Flores; Leonardi, Marco; Rinaldi, Andrea C

    2012-05-01

    Guatemala is one of the richest biodiversity hotspots worldwide, bursting a wild array of ecosystems that range from pine and mixed forests in the highlands to tropical rain forests in the extensive El Petén area, bordering Belize and Mexico. Despite this biological wealth, however, current knowledge on the Guatemalan mycobiota is particularly scant, in part because of the prolonged civil war that has prevented exploration of many ecological niches. In the present paper, we report on the occurrence of Lactarius rimosellus Peck-a rarely discussed species-in oak-pine mixed forests in the Guatemalan highlands and describe the relevant ectomycorrhizae formed with Quercus sp. by means of molecular and morpho-anatomical tools. On the phylogenetic trees constructed on the basis of the partial LSU sequence, sporocarp- and ectomycorrhizae-derived sequences formed a common, statistically supported clade. The structural features of the ectomycorrhizae of L. rimosellus were generally found to match those described on various hosts for other Lactarius species belonging to the subgenus Russularia, where L. rimosellus has been traditionally assigned. These mycorrhizae are characterized by a pseudoparenchymatous outer mantle layer, with epidermoid or angular hyphal cells, and a plectenchymatous inner mantle layer; lactifers are embedded either in the middle and/or inner mantle layer. In the framework of a more general, ongoing study of the ethnomycology of the Maya populations in the Guatemalan highlands, we also report on the traditional knowledge about Lactarius mushrooms and their uses among native people. © Springer-Verlag 2012

  19. Cadmium induced changes in Solidago chilensis Meyen (Asteraceae) grown on organically fertilized soil with reference to mycorrhizae, metabolism, anatomy and ultrastructure.

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    Pereira, Lidiane Silva; de Araújo, Romária Pereira; de Oliveira, Priscila Souza; da Silva, Leandro Dias; Alves, Patricia Alves Casaes; Fernandes, Valéria Ferreira; Gross, Eduardo

    2018-04-15

    Solidago chilensis Meyen (Asteraceae) is a medicinal important plant with few studies on nutrition and metabolism and none information on cadmium phytotoxicity. The objective of this study was to investigate Cd induced responses on the growth and metabolism in S. chilensis and on arbuscular mycorrhiza (AM). The experiment was carried out in a greenhouse, consisting of a 5 × 4 factorial with five doses of manure (0, 3.5, 7, 14 and 21gdm-3) and four doses of cadmium (0, 25, 50 and 75mgdm-3) applied to a Dystrophic Ultisol. After 250 days of plant cultivation, biomass, nutrient content, photosynthetic rate, guaiacol peroxidase activity, mycorrhizal colonization, glomalin content, anatomical and ultrastucture were evaluated. Plants were significantly affected by interaction of manure and Cd doses with anatomical, ultrastructural, physiological and nutritional modifications. Manure applied into Cd contaminated soil significantly improved mycorrhizal colonization and glomalin production. The highest organic manure dose (21gdm-3) alleviated toxicity symptoms of Cd on S. chilensis. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Structural characterization and molecular identification of arbuscular mycorrhiza morphotypes of Alzatea verticillata (Alzateaceae), a prominent tree in the tropical mountain rain forest of South Ecuador.

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    Beck, Adela; Haug, Ingeborg; Oberwinkler, Franz; Kottke, Ingrid

    2007-10-01

    The vast majority of the highly diverse trees in the tropical mountain rain forest of South Ecuador form arbuscular mycorrhizas, and previous molecular investigations revealed a high diversity of fungi. In this study, we present a first trial to link fungal DNA-sequences with defined morphotypes characterized on the basis of partly new mycelial features obtained from field material of one tree species, Alzatea verticillata. Fine roots were halved lengthwise to study the mycelium anatomy on one half and to obtain fungal nuclear rDNA coding for the small subunit rRNA of Glomeromycota from the other half. Light microscopy revealed conspicuously large amounts of mycelium attaching to the surface of the rootlets. The mycelium formed fine- or large-branched appressoria-like plates, vesicles of regular or irregular shape, and very fine, multibranched structures ensheathed by septate hyphae. These previously undescribed features of the supraradical mycelia combined with intraradical mycelium structures were used for distinguishing of four main morphogroups and subordinate 14 morphotypes. DNA sequences of Glomus group A, Acaulospora and Gigaspora, were obtained and linked to three morphogroups. Two sequence types within Glomus group A could be tentatively associated to subordinate morphotypes.

  1. Influence of different mineral nitrogen sources (NO3(-)-N vs. NH4(+)-N) on arbuscular mycorrhiza development and N transfer in a Glomus intraradices-cowpea symbiosis.

    Science.gov (United States)

    Ngwene, Benard; Gabriel, Elke; George, Eckhard

    2013-02-01

    Labeled nitrogen ((15)N) was applied to a soil-based substrate in order to study the uptake of N by Glomus intraradices extraradical mycelium (ERM) from different mineral N (NO(3)(-) vs. NH(4)(+)) sources and the subsequent transfer to cowpea plants. Fungal compartments (FCs) were placed within the plant growth substrate to simulate soil patches containing root-inaccessible, but mycorrhiza-accessible, N. The fungus was able to take up both N-forms, NO(3)(-) and NH(4)(+). However, the amount of N transferred from the FC to the plant was higher when NO(3)(-) was applied to the FC. In contrast, analysis of ERM harvested from the FC showed a higher (15)N enrichment when the FC was supplied with (15)NH(4)(+) compared with (15)NO(3)(-). The (15)N shoot/root ratio of plants supplied with (15)NO(3)(-) was much higher than that of plants supplied with (15)NH(4)(+), indicative of a faster transfer of (15)NO(3)(-) from the root to the shoot and a higher accumulation of (15)NH (4)(+) in the root and/or intraradical mycelium. It is concluded that hyphae of the arbuscular mycorrhizal fungus may absorb NH(4)(+) preferentially over NO(3)(-) but that export of N from the hyphae to the root and shoot may be greater following NO(3)(-) uptake. The need for NH(4)(+) to be assimilated into organically bound N prior to transport into the plant is discussed.

  2. Fungal and plant gene expression in the Tulasnella calospora-Serapias vomeracea symbiosis provides clues about nitrogen pathways in orchid mycorrhizas.

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    Fochi, Valeria; Chitarra, Walter; Kohler, Annegret; Voyron, Samuele; Singan, Vasanth R; Lindquist, Erika A; Barry, Kerrie W; Girlanda, Mariangela; Grigoriev, Igor V; Martin, Francis; Balestrini, Raffaella; Perotto, Silvia

    2017-01-01

    Orchids are highly dependent on their mycorrhizal fungal partners for nutrient supply, especially during early developmental stages. In addition to organic carbon, nitrogen (N) is probably a major nutrient transferred to the plant because orchid tissues are highly N-enriched. We know almost nothing about the N form preferentially transferred to the plant or about the key molecular determinants required for N uptake and transfer. We identified, in the genome of the orchid mycorrhizal fungus Tulasnella calospora, two functional ammonium transporters and several amino acid transporters but found no evidence of a nitrate assimilation system, in agreement with the N preference of the free-living mycelium grown on different N sources. Differential expression in symbiosis of a repertoire of fungal and plant genes involved in the transport and metabolism of N compounds suggested that organic N may be the main form transferred to the orchid host and that ammonium is taken up by the intracellular fungus from the apoplatic symbiotic interface. This is the first study addressing the genetic determinants of N uptake and transport in orchid mycorrhizas, and provides a model for nutrient exchanges at the symbiotic interface, which may guide future experiments. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

  3. Arbuscular mycorrhiza in species of Commelinidae (Liliopsida in the state of Pernambuco (Brazil Micorrizas arbusculares em espécies de Commelinidae (Liliopsida no Estado de Pernambuco (Brasil

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    Gladstone Alves da Silva

    2001-08-01

    Full Text Available Mycorrhiza are a mutualistic symbiosis between fungi and plant roots, the main benefit to the plant being increased nutrient uptake. The arbuscular is the most important kind of mycorrhiza for agriculture and it is widespread in occurrence and distribution in most ecosystems. The aim of this work was to study the mycorrhizal status of the species of Commelinidae that occur in the State of Pernambuco. Plant roots, collected in ten municipalities, were washed, cleared in KOH, stained with Trypan blue in lactoglycerol and observed under a light microscope in order to assess presence and identification of the mycorrhizal type. Percentage of root colonization was evaluated by the gridline intersect method. Forty specimens representing 30 species were observed. From these specimens, 70% were colonized by arbuscular mycorrhizal fungi (AMF. In one family (Typhaceae, mycorrhizal structures were not observed, in two of them (Eriocaulaceae and Juncaceae all specimens showed the association, and three families (Commelinaceae, Cyperaceae and Poaceae presented specimens with or without AMF. In some of the roots, other fungi were observed together with the AMF. The results indicate that AMF are widely distributed among species of Commelinidae in Pernambuco, being probably important for their establishment in the areas visited.Micorrizas são associações simbióticas mutualísticas formadas entre fungos e raízes de plantas, sendo o principal benefício para a planta o aumento do aporte de nutrientes. Agronomicamente, a micorriza arbuscular (MA é o tipo mais importante de micorrizas e apresenta-se distribuído na maioria dos ecossistemas. O objetivo deste trabalho foi estudar a condição micorrízica de espécies de Commelinidae que ocorrem no Estado de Pernambuco. Raízes dessas plantas, coletadas em 10 municípios, foram lavadas, clareadas em KOH, coradas com azul de Tripano em lactoglicerol e observadas em microscópio para determinação da presença e

  4. Functional analysis of the novel mycorrhiza-specific phosphate transporter AsPT1 and PHT1 family from Astragalus sinicus during the arbuscular mycorrhizal symbiosis.

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    Xie, Xianan; Huang, Wu; Liu, Fengchuan; Tang, Nianwu; Liu, Yi; Lin, Hui; Zhao, Bin

    2013-05-01

    Arbuscular mycorrhizas contribute significantly to inorganic phosphate (Pi) uptake in plants. Gene networks involved in the regulation and function of the Pht1 family transporters in legume species during AM symbiosis are not fully understood. In order to characterize the six distinct members of Pht1 transporters in mycorrhizal Astragalus sinicus, we combined cellular localization, heterologous functional expression in yeast with expression/subcellular localization studies and reverse genetics approaches in planta. Pht1;1 and Pht1;4 silenced lines were generated to uncover the role of the newly discovered dependence of the AM symbiosis on another phosphate transporter AsPT1 besides AsPT4. These Pht1 transporters are triggered in Pi-starved mycorrhizal roots. AsPT1 and AsPT4 were localized in arbuscule-containing cells of the cortex. The analysis of promoter sequences revealed conserved motifs in both AsPT1 and AsPT4. AsPT1 overexpression showed higher mycorrhization levels than controls for parameters analysed, including abundance of arbuscules. By contrast, knockdown of AsPT1 by RNA interference led to degenerating or dead arbuscule phenotypes identical to that of AsPT4 silencing lines. AsPT4 but not AsPT1 is required for symbiotic Pi uptake. These results suggest that both, AsPT1 and AsPT4, are required for the AM symbiosis, most importantly, AsPT1 may serve as a novel symbiotic transporter for AM development. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

  5. Monotropa uniflora: morphological and molecular assessment of mycorrhizae retrieved from sites in the sub-boreal spruce biogeoclimatic zone in central British Columbia.

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    Young, B W; Massicotte, H B; Tackaberry, L E; Baldwin, Q F; Egger, K N

    2002-04-01

    Plant species in the subfamily Monotropoideae are achlorophyllous and have developed a complex mode of nutrition, receiving photosynthates from neighboring trees via shared fungi. To explore the mycorrhizal associations of Monotropa uniflora in central British Columbia (B.C.), plants were sampled from three sites: a Betula-dominated site and two sites with a mixture of conifer and hardwood trees. Fifteen M. uniflora root-clusters were sampled (five per site) and the mycorrhizal diversity was assessed using morphological and molecular (PCR-RFLP analysis and DNA sequencing) methods. Both methods showed that root-clusters (often comprising several hundred mycorrhizal tips) belonging to the same plant appeared to involve fungus monocultures in the family Russulaceae. All mycorrhizae exhibited typical Russula morphology and had mantle cystidia. Two root-clusters, one each from sites 1 and 3, lacked one of the two types of cystidia present on all other root-clusters. PCR-RFLP analysis resulted in three fragment patterns for the 15 root clusters. One molecular fragment pattern included the two root-clusters displaying the single cystidium type plus an additional root-cluster with both cystidia types. DNA sequencing of a portion of the ITS2 region of the ribosomal DNA suggests that the three variants represent different species; two of the variants clustered with the hypogeous fungi Martellia and Gymnomyces. The study provides increased evidence of low diversity and high specificity in the Monotropa-fungus relationship and suggests that M. uniflora associates uniquely with fungi in the family Russulaceae in central B.C.

  6. Regulation of root morphogenesis in arbuscular mycorrhizae: what role do fungal exudates, phosphate, sugars and hormones play in lateral root formation?

    Science.gov (United States)

    Fusconi, Anna

    2014-01-01

    Arbuscular mycorrhizae (AMs) form a widespread root-fungus symbiosis that improves plant phosphate (Pi) acquisition and modifies the physiology and development of host plants. Increased branching is recognized as a general feature of AM roots, and has been interpreted as a means of increasing suitable sites for colonization. Fungal exudates, which are involved in the dialogue between AM fungi and their host during the pre-colonization phase, play a well-documented role in lateral root (LR) formation. In addition, the increased Pi content of AM plants, in relation to Pi-starved controls, as well as changes in the delivery of carbohydrates to the roots and modulation of phytohormone concentration, transport and sensitivity, are probably involved in increasing root system branching. This review discusses the possible causes of increased branching in AM plants. The differential root responses to Pi, sugars and hormones of potential AM host species are also highlighted and discussed in comparison with those of the non-host Arabidopsis thaliana. Fungal exudates are probably the main compounds regulating AM root morphogenesis during the first colonization steps, while a complex network of interactions governs root development in established AMs. Colonization and high Pi act synergistically to increase root branching, and sugar transport towards the arbusculated cells may contribute to LR formation. In addition, AM colonization and high Pi generally increase auxin and cytokinin and decrease ethylene and strigolactone levels. With the exception of cytokinins, which seem to regulate mainly the root:shoot biomass ratio, these hormones play a leading role in governing root morphogenesis, with strigolactones and ethylene blocking LR formation in the non-colonized, Pi-starved plants, and auxin inducing them in colonized plants, or in plants grown under high Pi conditions.

  7. Proteomics provides insights into biological pathways altered by plant growth promoting bacteria and arbuscular mycorrhiza in sorghum grown in marginal soil.

    Science.gov (United States)

    Dhawi, Faten; Datta, Rupali; Ramakrishna, Wusirika

    2017-02-01

    Sorghum is an economically important crop, a model system for gene discovery and a biofuel source. Sorghum seedlings were subjected to three microbial treatments, plant growth promoting bacteria (B), arbuscular mycorrhizal (AM) fungi mix with two Glomus species (G. aggregatum and G. etunicatum), Funelliformis mosseae and Rhizophagus irregularis (My), and B and My combined (My+B). Proteomic analysis was conducted followed by integration with metabolite, plant biomass and nutrient data. Out of 366 differentially expressed proteins in sorghum roots, 44 upregulated proteins overlapping among three treatment groups showed positive correlation with sorghum biomass or element uptake or both. Proteins upregulated only in B group include asparagine synthetase which showed negative correlation with biomass and uptake of elements. Phosphoribosyl amino imidazole succinocarboxamide protein with more than 50-fold change in My and My+B groups correlated positively with Ca, Cu, S and sucrose levels in roots. The B group showed the highest number of upregulated proteins among the three groups with negative correlation with sorghum biomass and element uptake. KEGG pathway analysis identified carbon fixation as the unique pathway associated with common upregulated proteins while biosynthesis of amino acids and fatty acid degradation were associated with common downregulated proteins. Protein-protein interaction analysis using STRING identified a major network with thirteen downregulated proteins. These findings suggest that plant-growth-promoting-bacteria alone or in combination with mycorrhiza enhanced radical scavenging system and increased levels of specific proteins thereby shifting the metabolism towards synthesis of carbohydrates resulting in sorghum biomass increase and uptake of nutrients. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Regulation of root morphogenesis in arbuscular mycorrhizae: what role do fungal exudates, phosphate, sugars and hormones play in lateral root formation?

    Science.gov (United States)

    Fusconi, Anna

    2014-01-01

    Background Arbuscular mycorrhizae (AMs) form a widespread root–fungus symbiosis that improves plant phosphate (Pi) acquisition and modifies the physiology and development of host plants. Increased branching is recognized as a general feature of AM roots, and has been interpreted as a means of increasing suitable sites for colonization. Fungal exudates, which are involved in the dialogue between AM fungi and their host during the pre-colonization phase, play a well-documented role in lateral root (LR) formation. In addition, the increased Pi content of AM plants, in relation to Pi-starved controls, as well as changes in the delivery of carbohydrates to the roots and modulation of phytohormone concentration, transport and sensitivity, are probably involved in increasing root system branching. Scope This review discusses the possible causes of increased branching in AM plants. The differential root responses to Pi, sugars and hormones of potential AM host species are also highlighted and discussed in comparison with those of the non-host Arabidopsis thaliana. Conclusions Fungal exudates are probably the main compounds regulating AM root morphogenesis during the first colonization steps, while a complex network of interactions governs root development in established AMs. Colonization and high Pi act synergistically to increase root branching, and sugar transport towards the arbusculated cells may contribute to LR formation. In addition, AM colonization and high Pi generally increase auxin and cytokinin and decrease ethylene and strigolactone levels. With the exception of cytokinins, which seem to regulate mainly the root:shoot biomass ratio, these hormones play a leading role in governing root morphogenesis, with strigolactones and ethylene blocking LR formation in the non-colonized, Pi-starved plants, and auxin inducing them in colonized plants, or in plants grown under high Pi conditions. PMID:24227446

  9. The soybean mycorrhiza-inducible phosphate transporter gene, GmPT7, also shows localized expression at the tips of vein endings of senescent leaves.

    Science.gov (United States)

    Inoue, Yuki; Kobae, Yoshihiro; Omoto, Eiji; Tanaka, Aiko; Banba, Mari; Takai, Shoko; Tamura, Yosuke; Hirose, Aya; Komatsu, Kunihiko; Otagaki, Shungo; Matsumoto, Shogo; Taniguchi, Mitsutaka; Masuta, Chikara; Ishimoto, Masao; Hata, Shingo

    2014-12-01

    GmPT7 was originally identified as an arbuscular mycorrhiza-inducible gene of soybean that encodes a member of subfamily I in the PHOSPHATE TRANSPORTER 1 family. In the present study, we established conditions under which a number of dwarf soybean plants complete their life cycles in a growth chamber. Using this system, we grew transgenic soybean with a GmPT7 promoter-β-glucuronidase fusion gene and evaluated GmPT7 expression in detail. GmPT7 was highly expressed in mature, but not in collapsed, arbuscule-containing cortical cells, suggesting its importance in the absorption of fungus-derived phosphate and/or arbuscule development. GmPT7 was also expressed in the columella cells of root caps and in the lateral root primordia of non-mycorrhizal roots. The expression of GmPT7 occurred only in the late stage of phosphorus translocation from leaves to seeds, after water evaporation from the leaves ceased, and later than the expression of GmUPS1-2, GmNRT1.7a and GmNRT1.7b, which are possibly involved in nitrogen export. GmPT7 expression was localized in a pair of tracheid elements at the tips of vein endings of senescent leaves. Transmission electron microscopy revealed that the tip tracheid elements in yellow leaves were still viable and had intact plasma membranes. Thus, we think that GmPT7 on the plasma membranes transports phosphate from the apoplast into the tip elements. GmPT7 knockdown resulted in no significant effects, the function of GmPT7 remaining to be clarified. We propose a working model in which phosphate incorporated in vein endings moves to seeds via xylem to phloem transfer. © The Author 2014. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  10. The Effects of Organic Fertilizers and Mycorrhizae Inoculation (Glomus mosseae and G. intraradices on Quantitative and Qualitative Yield of Dwarf Chicory (Cichorium pumilum Jacq. in Different Cuttings

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    R. Naghibi

    2016-02-01

    Full Text Available Introduction: In recent years many farmers in Iran interested in to cultivate and produce different medicinal plants which are so important in traditional agriculture in Iran. In order to reduce the environmental impacts of using chemical inputs and also to increase the quality of plant secondary metabolite components, the emphasis is on sustainable agriculture base on using of organic and biological fertilizer. Dwarf chicory (Cichorium pumilum Jacq. is an annual plant from Asteraceae family. Dwarf chicory is classified by jacq as subspecies of the cultivated species Cichorium endeva which consumed for healing a variety of diseases such as bacterial infection, poisoning and rheumatism. The use of organic fertilizer in the form of humic acid and fulvic acid play an important role in sustainable agriculture. Humic substances can be added to the soil for improvement the crop yield. A benefit of humic acid due to its ability to complex metal ions and form aqueous complexes with micronutrients and also may form an enzymatically active complex, which can be carry on reactions that are usually assigned to the metabolic activity of living microorganisms. In additional of using organic fertilizers, the biological fertilizer like mycorrhiza fungi is a good approach in agriculture. Mycorrhizal fungi have been used to enhance the plant growth and yield of medicinal crops and to help maintain good soil health and fertility that contributes to a greater extent to a sustainable yield and good quality of the products. The present study was conducted to evaluate the effects of organic fertilizers and mycorrhizae inoculation on quantitative and qualitative characteristics of dwarf chicory (Cichorium pumilum Jacq. in different cuttings. Materials and Methods: The experiment was carried out in a factorial layout based on randomized complete block design with three replications at Research Station, Faculty of Agriculture, Ferdowsi University of Mashhad (59°28 E and

  11. BIOFERTILIZATION WITH RHIZOBACTERIA AND A CONSORTIUM OF ARBUSCULAR MYCORRHIZAL FUNGI IN CITRUS ROOTSTOCKS

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    Roberto Gregorio Chiquito-Contreras

    2012-11-01

    Full Text Available Biofertilization of plants with rhizobacteria and vesicular arbuscular mycorrhizae (mycorrhizal consortium, potentially promotes plant growth and health, and reduces the use of agrochemicals. The effect of individual and combined biofertilization with three strains of rhizobacteria and the mycorrhizal consortium (MTZ-1 was evaluated under nursery conditions on the growth of rootstocks of Citrus volkameriana and Rangpur lime grafted with Tahiti lime. Plants were inoculated individually and combined with the rhizobacteria strains FCA-8, FCA-56 and FCA-60 of Pseudomonas putida, and with MTZ-1; 50 % fertilization also was applied (18-46-00 N-P-K and compared with controls that received nursery management and 100 % fertilization. A split-plot experimental design with five replications per treatment was established. Individual and combined biofertilization with the three strains of bacteria and MTZ-1 positively promoted the growth of C. volkameriana, and Rangpur lime grafted with Tahiti lime, similar to the control with 100 % fertilization. The nutrient content of Tahiti lime leaves was similar to the control for both rootstocks. The presence of rhizobacterial and mycorrhizal populations in the combined biofertilization treatments demonstrated a positive synergism in the colonization of rootstock roots. Results demonstrate the potential of the three strains of P. putida and the MTZ-1 mycorrhizal consortium on the promotion of plant growth and assimilation of nutrients.

  12. Gene expression analyses in tomato near isogenic lines provide evidence for ethylene and abscisic acid biosynthesis fine-tuning during arbuscular mycorrhiza development.

    Science.gov (United States)

    Fracetto, Giselle Gomes Monteiro; Peres, Lázaro Eustáquio Pereira; Lambais, Marcio Rodrigues

    2017-07-01

    Plant responses to the environment and microorganisms, including arbuscular mycorrhizal fungi, involve complex hormonal interactions. It is known that abscisic acid (ABA) and ethylene may be involved in the regulation of arbuscular mycorrhiza (AM) and that part of the detrimental effects of ABA deficiency in plants is due to ethylene overproduction. In this study, we aimed to determine whether the low susceptibility to mycorrhizal colonization in ABA-deficient mutants is due to high levels of ethylene and whether AM development is associated with changes in the steady-state levels of transcripts of genes involved in the biosynthesis of ethylene and ABA. For that, tomato (Solanum lycopersicum) ethylene overproducer epinastic (epi) mutant and the ABA-deficient notabilis (not) and sitiens (sit) mutants, in the same Micro-Tom (MT) genetic background, were inoculated with Rhizophagus clarus, and treated with the ethylene biosynthesis inhibitor aminoethoxyvinylglycine (AVG). The development of AM, as well as the steady-state levels of transcripts involved in ethylene (LeACS2, LeACO1 and LeACO4) and ABA (LeNCED) biosynthesis, was determined. The intraradical colonization in epi, not and sit mutants was significantly reduced compared to MT. The epi mutant completely restored the mycorrhizal colonization to the levels of MT with the application of 10 µM of AVG, probably due to the inhibition of the ACC synthase gene expression. The steady-state levels of LeACS2 and LeACO4 transcripts were induced in mycorrhizal roots of MT, whereas the steady-state levels of LeACO1 and LeACO4 transcripts were significantly induced in sit, and the steady-state levels of LeNCED transcripts were significantly induced in all genotypes and in mycorrhizal roots of epi mutants treated with AVG. The reduced mycorrhizal colonization in sit mutants seems not to be limited by ethylene production via ACC oxidase regulation. Both ethylene overproduction and ABA deficiency impaired AM fungal

  13. Fungos micorrízicos vesículo-arbusculares em rizosferas de plantas em dunas do Parque Estadual da Ilha do Cardoso, São Paulo, Brasil: (1 Taxonomia Vesicular-arbuscular mycorrhizal fungi from rhizospheres of dunes plants of Parque Estadual da Ilha do Cardoso, São Paulo State, Brazil (1: taxonomy

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    S. F. B Trufem

    1989-01-01

    Full Text Available De março/1988 a março/1989, mensalmente, foram coletadas o total de 450 amostras de solo de rizosferas de plantas de dunas do Parque Estadual da Ilha do Cardoso, Estado de Sáo Paulo, com a finalidade de se verificar a ocorrência de fungos micorrízicos vesículo-arbusculares (MVA. As plantas mais constantemente investigadas foram: Baccharis trimera DC. (Compositae, Blutaparon portulacoides (St. Hü. Mears (Amaranthaceae, Dalbergia hecastaphylla (L. Taub. (Legurninosae, Hydrocotyle bonariensis Lam. (Umbelliferae,Ipomoeapes-caprae (L.Sweet(Convolvulaceae, Polygaid cyparisseas St. Hül & Moq. (Polygalaceae, além de gramíneas, ciperáceas e outras, que foram coletadas mais esporadicamente. O solo foi tratado pela técnica de decantação e peneiramento em via úmida. Foram verificados 14 taxons de fungos MVA: Acaulospora scrobiculata Trappe, Acaulospora tuberculata Janos & Trappe, Cigaspora gigantea (Nicol. & Gerd. Gerd. & Trappe, Glomus fasciculatum (Thaxter Gerd. & Trappe emend. Walker & Koske, Glomus globiferum Koske & Walker, Glomus monosporum Gerd. & Trappe, Sclerocystis sinuosa Gerd. & Bakshi, Scutellospora calospora (Nicol & Gerd Walker & Sanders, Scutellospora coralloidea (Trappe, Gerd. & Ho (Walker & Sanders, Scutellospora gilmorei (Trappe & Gerd. Walker & Sanders, Scutellospora gregaria (Schenck & Nicol. Walker & Sanders, Scutellospora pérsica (Koske & Walker Walker & Sanders, Scutellospora verrucosa Koske & Walker Walker & Sanders e Scutellospora sp. São apresentadas descrições taxonómicas, comentarios e murônimos dos taxons verificados.Monthly, from March/1988 to March/1989 were collected the total of 450 soil samples from rhizospheres of plants from dunes of Parque Estadual da Ilha do Cardoso, São Paulo State, Brazil, to report the occurrence of VANÍ fungus. The investigated plants were: Baccharis trímera DC. (Compositae, Blutaparon portulacoides (St. Hil. Mears (Amaranthaceae, Dalbergia hecastaphylla (L. Taub. (Legumiosae, Hydrocotyle bonariensis Lam. (Umbelliferae, Ipomoea pes-caprae (L. Sweet (Convolvulaceae, Polygala cyparisseas St. Hill & Moq. (Polygalaceae; Gramineae, Cyperaceae and other plants were occasionaly collected. The soil was prepared according the wet sieving and decanting technique. It was observed the following 14 taxa of VA M fungüs: Acaulospora scrobiculata Trappe, Acaulospora tuberculata Janos & Trappe, Gigaspora gigantea (Nicol. & Gerd Gerd & Trappe, Glomus fasciculatum (Thaxter Gerd. & Trappe emend. Walker & Koske, Glomus globiferum Koske & Walker, Glomus monosporum Gerd. & Trappe, Sclerocystís sinuosa Gerd. & Bakshi, Scutellospora calospora (Nicol. & Gerd. Walker & Sanders, Scutellospora collaroidea (Trappe, Gerd. & Ho Walker & Sanders, Scutellospora gilmorei (Trappe & Gerd. Walker & Sanders, Scutellospora gregaria (Schénck & Nicol. Walker & Sanders, Scutellospora pérsica (Koske & Walker Walker & Sanders, Scutellospora verrucosa (Koske & Walker Walker & Sanders and Scutellospora sp. Are presented taxonomical, coments and muronyms of the studied taxa.

  14. Heavy ion and proton beams in high resolution imaging of a fungi spore specimen using STIM tomography

    Science.gov (United States)

    Formenti, P.; Breese, M. B. H.; Connell, S. H.; Doyle, B. P.; Drummond, M. L.; Machi, I. Z.; Maclear, R. D.; Schaaff, P.; Sellschop, J. P. F.; Bench, G.; Sideras-Haddad, E.; Antolak, A.; Morse, D.

    1997-07-01

    Scanning transmission ion microscopy (STIM) tomography as a 3-D imaging technique has been shown to have a range of applications. The energy of the transmitted ion is detected with nearly 100% efficiency as a function of position in the transverse plane. The parameters relating to transmitted ion energy loss in the sample are imaged with statistics given by the energy loss process rather than Poisson counting statistics. This enables very fast collection of a set of relatively noise-free 2-D images. Each image is collected after a small rotation of the sample, and a complete 3-D representation of the sample may be tomographically reconstructed. The small beam currents necessary mean that the technique is non-destructive. One of the fields where these non-destructive 3-D density structure maps are particularly useful is in the analysis of biological tissue. The variation of energy loss with projectile atomic number may be exploited to tune the energy loss contrast to the size and density of the sample (heavy ion STIM). This work develops this point, and applies it to the imaging of the microscopic structure of a 90 μm diameter mycorrhiza fungi spore. This specimen has been imaged non-destructively in 3-D using both a 36 MeV 12C beam and a 2.2 MeV proton beam, both with a spatial resolution of about 1 μm. The gain in contrast in the carbon median energy loss maps was dramatic as expected. The corresponding improvement in the tomogram was found to be visible but less dramatic. The tomographic sections as well as the median energy loss maps of the vesicular-arbuscular mycorrhiza fungi spore clearly show the internal structure. Wall morphology data has relevance to germination behaviour of the spores.

  15. Mycorrhizas and tropical soil fertility

    NARCIS (Netherlands)

    Cardoso, I.M.; Kuyper, T.W.

    2006-01-01

    Major factors that constrain tropical soil fertility and sustainable agriculture are low nutrient capital, moisture stress, erosion, high P fixation, high acidity with aluminium toxicity, and low soil biodiversity. The fragility of many tropical soils limits food production in annual cropping

  16. Dipterocarpaceae : tree - mycorrhizae - seedling connections

    NARCIS (Netherlands)

    Yasman, I.

    1995-01-01

    Research on natural regeneration of Dipterocarpaceae is described. Work in greenhouse experiments, in planting experiments in natural forests and from monitoring of natural regeneration in undisturbed natural forest are discussed. In addition work on photosynthesis measurements is

  17. Mycorrhiza-induced lower oxidative burst is related with higher antioxidant enzyme activities, net H2O2 effluxes, and Ca2+ influxes in trifoliate orange roots under drought stress.

    Science.gov (United States)

    Zou, Ying-Ning; Huang, Yong-Ming; Wu, Qiang-Sheng; He, Xin-Hua

    2015-02-01

    Mechanisms of arbuscular mycorrhiza (AM)-induced lower oxidative burst of host plants under drought stress (DS) are not elucidated. A noninvasive microtest technology (NMT) was used to investigate the effects of Funneliformis mosseae on net fluxes of root hydrogen peroxide (H2O2) and calcium ions (Ca2+) in 5-month-old Poncirus trifoliata, in combination with catalase (CAT) and superoxide dismutase (SOD) activities as well as tissue superoxide radical (O2•-) and H2O2 concentrations under DS and well-watered (WW) conditions. A 2-month DS (55% maximum water holding capacity of growth substrates) significantly inhibited AM fungal root colonization, while AM symbiosis significantly increased plant biomass production, irrespective of water status. F. mosseae inoculation generally increased SOD and CAT activity but decreased O2•- and H2O2 concentrations in leaves and roots under WW and DS. Compared with non-AM seedlings, roots of AM seedlings had significantly higher net H2O2 effluxes and net Ca2+ influxes, especially in the meristem zone, but lower net H2O2 efflux in the elongation zone. Net Ca2+ influxes into roots were significantly positively correlated with root net H2O2 effluxes but negatively with root H2O2 concentrations. Results from this study suggest that AM-induced lower oxidative burst is related with higher antioxidant enzyme activities, root net H2O2 effluxes, and Ca2+ influxes under WW and DS.

  18. Rendimento de massa seca e absorção de fósforo pelo milho afetado pela aplicação de fósforo, calcário e inoculação com fungos micorrízicos Dry matter of corn and phosphorus uptake as affected by liming, rates of phosphorus, and mycorrhizae inoculation

    Directory of Open Access Journals (Sweden)

    Julio Cesar Pires Santos

    1996-04-01

    Full Text Available A colonização do sistema radicular com micorrizas pode aumentar a absorção de P e com isto aumentar o crescimento das plantas, o que parece ser mais comum em solos com baixa disponibilidade de P. No presente trabalho, a inoculação com fungos micorrízicos arbusculares (FMA, objetivou avaliar seu efeito na morfologia do sistema radicular, na produção de massa seca e na absorção de fósforo pelo milho. Utilizou-se o latossolo bruno argiloso, e os tratamentos consistiram de dois valores de pH (4,8 e 5,5, duas doses de fósforo (25 e 100mg P/kg de solo e inoculação com FMA. O experimento foi conduzido em casa de vegetação com cinco repetições, distribuídas no delineamento experimental completamente casualisado. Aos 46 dias após a emergência as plantas foram colhidas, e nelas determinou-se a produção de massa seca de parte aérea e de raízes, o comprimento e o raio médio radicular. a porcentagem e intensidade de colonização micorrízica e a absorção de fósforo. A inoculação com FMA aumentou a CM mas não afetou a produção de massa seca e absorção de fósforo pelo milho, embora as raízes mostrassem menor comprimento, indicando que as hifas extraradiculares compensaram o crescimento radicular. A adição de fósforo e a elevação do pH aumentaram a massa seca da parte aérea e raízes, a absorção de fósforo e o comprimento radicular.The existence of mycorrhiza in the plant roots may increase phosphorus uptake and thus crop yield. This effect, however, seems to occur only in phosphorus deficient soils. The objetive of this work was to evaluate the effect of soil pH, rates of phosphorus addition, and mycorrhiza inoculation on dry matter yield of corn and on phosphorus uptake. The experiment was run in a greenhouse, using an oxisol, with five replicates per treatment distributed in a completely randomized experimental design. The treatments, a 2x2x2 factorial, were two rates of phosphorus (25 and 100mg P/kg, two p

  19. Colonização por fungos micorrízicos arbusculares e teores de nutrientes em cinco cultivares de bananeiras em um Latossolo da Amazônia Arbuscular mycorrhizae fungi and nutrient contents in five banana cultivars on an Amazonian Oxisol

    Directory of Open Access Journals (Sweden)

    Arlem Nascimento de Oliveira

    2005-06-01

    Full Text Available A bananeira é uma espécie de grande importância sócio-econômica na Amazônia, mas precisa de altos insumos agrícolas para ser produtiva. A associação com fungos micorrízicos arbusculares (FMAs pode minimizar as suas necessidades nutricionais nos solos pobres da Amazônia. O presente trabalho objetivou verificar a ocorrência de associação micorrízica e os teores de nutrientes em bananeiras cultivadas em um Latossolo ácido da Amazônia. O bananal encontra-se deficiente em macro (Ca, Mg e P e micronutrientes (Fe, Mn, Zn e Cu. A colonização micorrízica foi de 54,9 %, no cultivar Mysore; 51,5 %, na Maçã, 47,6 %, na Pacovan; 47,3 %, na Nanica, e 44,7 %, na banana Prata, ocorrendo diferenças significativas. Os cultivares Mysore e Maçã apresentaram maiores índices de colonização radicular nos meses de janeiro e agosto, enquanto a Nanica, nos meses de julho, janeiro e agosto. Os cultivares Pacovan e Prata não apresentaram variações significativas de colonização por FMAs nas épocas estudadas. Nos cultivares, a associação micorrízica correlacionou-se significativamente com os teores de K, Mg, P e Zn no cultivar Maçã, K e P no Nanica e Zn no Prata.The Amazon banana plant is of great socio-economical importance, despite its requirement for high agricultural input in order to obtain good yields. An association with arbuscular mycorrhizae fungi could minimize the crop's nutritional needs in the poor soils of the Amazon. The present study aimed at verifying how the plant-fungus mycorrhizal symbiosis influences nutrient concentration in five varieties of adult banana plants cultivated in an acid Amazon Oxisol under field conditions. The banana plantation was defficient in macro (Ca, Mg and P and micronutrients (Fe, Mn, Zn and Cu. The mycorrhizae colonization varied from 33.6 to 66.5 % of the sampled roots. The average mycorrhizae colonization was 54.9 % in the Mysore, 51.5 % in Maçã, 47.6 % in Pacovan, 47.3 % in Nanica, and

  20. Interactive effects of silicon and arbuscular mycorrhiza in modulating ascorbate-glutathione cycle and antioxidant scavenging capacity in differentially salt-tolerant Cicer arietinum L. genotypes subjected to long-term salinity.

    Science.gov (United States)

    Garg, Neera; Bhandari, Purnima

    2016-09-01

    Salinity is the major environmental constraint that affects legume productivity by inducing oxidative stress. Individually, both silicon (Si) nutrition and mycorrhization have been reported to alleviate salt stress. However, the mechanisms adopted by both in mediating stress responses are poorly understood. Thus, pot trials were undertaken to evaluate comparative as well as interactive effects of Si and/or arbuscular mycorrhiza (AM) in alleviating NaCl toxicity in modulating oxidative stress and antioxidant defence mechanisms in two Cicer arietinum L. (chickpea) genotypes-HC 3 (salt-tolerant) and CSG 9505 (salt-sensitive). Plants subjected to different NaCl concentrations (0-100 mM) recorded a substantial increase in the rate of superoxide radical (O2 (·-)), H2O2, lipoxygenase (LOX) activity and malondialdehyde (MDA) content, which induced leakage of ions and disturbed Ca(2+)/Na(+) ratio in roots and leaves. Individually, Si and AM reduced oxidative burst by strengthening antioxidant enzymatic activities (superoxide dismutase (SOD), catalase (CAT) and guaiacol peroxidase (GPOX)). Si was relatively more efficient in reducing accumulation of stress metabolites, while mycorrhization significantly up-regulated antioxidant machinery and modulated ascorbate-glutathione (ASA-GSH) cycle. Combined applications of Si and AM complemented each other in reducing reactive oxygen species (ROS) build-up by further enhancing the antioxidant defence responses. Magnitude of ROS-mediated oxidative burden was lower in HC 3 which correlated strongly with more effective AM symbiosis, better capacity to accumulate Si and stronger defence response when compared with CSG 9505. Study indicated that Si and/or AM fungal amendments upgraded salt tolerance through a dynamic shift from oxidative destruction towards favourable antioxidant defence system in stressed chickpea plants.

  1. Review: Biological fertilization and its effect on medicinal and aromatic plants

    Directory of Open Access Journals (Sweden)

    KHALID ALI KHALID

    2012-11-01

    Full Text Available Khalid KA. 2012. Review: Biological fertilization and its effect on medicinal and aromatic plants. Nusantara Bioscience 4: 124-133. The need of increase food production in the most of developing countries becomes an ultimate goal to meet the dramatic expansion of their population. However, this is also associated many cases with a reduction of the areas of arable land which leaves no opinion for farmers but to increase the yield per unit area through the use of improved the crop varieties, irrigation and fertilization. The major problem facing the farmer is that he cannot afford the cost of these goods, particularly that of chemical fertilizers. Moreover, in countries where fertilizer production relies on imported raw materials, the costs are even higher for farmer and for the country. Besides this, chemical fertilizers production and utilization are considered as air, soil and water polluting operations. The utilization of bio-fertilizers is considered today by many scientists as a promising alternative, particularly for developing countries. Bio-fertilization is generally based on altering the rhizosphere flora, by seed or soil inoculation with certain organisms, capable of inducing beneficial effects on a compatible host. Bio-fertilizers mainly comprise nitrogen fixes (Rhizobium, Azotobacter, Azospirellum, Azolla or blue green algae, phosphate dissolvers or vesicular-arbuscular mycorrhizas and silicate bacteria. These organisms may affect their host plant by one or more mechanisms such as nitrogen fixation, production of growth promoting substances or organic acids, enhancing nutrient uptake or protection against plant pathogens. Growth characters, yield, essential oil and its constituents, fixed oil, carbohydrates, soluble sugars and nutrients contents of medicinal and aromatic plants were significantly affected by adding the biological fertilizers compared with recommended chemical fertilizers.

  2. PENGARUH INOKULASI MIKORIZA VESIKULA ARBUSKULA (MVA CAMPURAN TERHADAP KEMUNCULAN PENYAKIT LAYU FUSARIUM PADA TANAMAN TOMAT (Solanum lycopersicum

    Directory of Open Access Journals (Sweden)

    Uswatun Hasanah

    2017-03-01

    Full Text Available Tomato has an important role to fullfil the nutrition of society. The most important problem in the cultivation of tomatoes is fusarium wilt caused by Fusarium oxysporum it will attacking the plants from nursery to adult. One of the alternative control is use the Vesicles Arbuscular Mycorrhizae (VAM. The success of VAM infection in plants is determined by the dose and the inoculation. The aim of this research is to determine the effect of dose and mixture VAM inoculation to against the emergence of fusarium wilt in tomato plants and to determine the dosage mixture VAM inoculation as the most effective way for controlling fusarium wilt in tomato plants. The method of this research used experimental with completely randomized design. The experimental treatment consists of two types of treatment that are combined with used 5 doses of VAM mixture (0 g/plant, 10 g/plant, 12,5 g/plant, 15 g/plant, 17,5 g/plant and used two ways of inoculation ( inoculation when the seed is planted and inoculation when transplanting the seeds. Each treatment was repeated 3 times and each test are three plants. The parameters was observed the incubation period of the disease and the intensity of fusarium wilt as the main parameter and the measurement of pH, temperature, humidity room, and the degree of infection as supporting parameters. The results of this research showed that the dosage and inoculation of VAM mixture is not able to reduce the emergence of fusarium wilt on tomatoes, but it was able to extend the incubation period of fusarium wilt on tomato plants a dose with 10 g /plant inoculated plants when the seeds are planted and inoculation when transplanting the seeds.

  3. Utilization and mitigation of VAM/CMM emissions by a catalytic combustion gas turbine

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, K.; Yoshino, Y.; Kashihara, H. [Kawasaki Heavy Industries Ltd., Hyougo (Japan); Kajita, S.

    2013-07-01

    A system configured with a catalytic combustion gas turbine generator unit is introduced. The system has been developed using technologies produced by Kawasaki Heavy Industries, Ltd., such as small gas turbines, recuperators and catalytic combustors, and catalytic oxidation units which use exhaust heat from gas turbines. The system combusts (oxidizes) ventilation air methane (less than 1% concentration) and low concentration coal mine methane (30% concentration or less) discharged as waste from coal mines. Thus, it cannot only reduce the consumption of high- quality fuel for power generation, but also mitigate greenhouse gas emissions.

  4. "Potshemu Vam v Parizh ne vernutsja nazad ? A tsvetov aromat ! A tsvetov aromat !" / Galina Balashova

    Index Scriptorium Estoniae

    Balashova, Galina

    2000-01-01

    Eestist Pariisi läinud kunstniku Volodimir Makarenko loomingust. Tema töid saab näha galeriis Sammas näitusel "Tallinn-Pariis, kevad 2000", kus osalevad ka Pariisiga seotud kunstnikud A. Strahhov, S. Semerikov, V. Bachiu, V. Laur

  5. Võ k nam, a mõ k vam... / Nelli Kuznetsova

    Index Scriptorium Estoniae

    Kuznetsova, Nelli

    2008-01-01

    Vene Kunstnike Ühenduse 10. aastapäevale pühendatud kevadnäitus toimus Würthi galeriis ja Kohtla-Järve Linnagaleriis. Filmi näituste avamistest, eksponeeritud töödest ja aruteludest näidati Vene kultuurikeskuses. Slava Semerikovi, Anatoli Strahhovi ja Valeri Smirnovi maalidest. Vene Kunstnike Ühenduse tegemisi kommenteerib Valeri Smirnov

  6. Influencia de la fertilización, la época y la especie forrajera en la presencia Influence of fertilization, season, and forage species in presence of arbuscular mycorrhizae in a degraded Andisoil of Colombia

    Directory of Open Access Journals (Sweden)

    Arnulfo Gómez-Carabalí

    2011-01-01

    and percentage of root infection of arbuscular mycorrhiza increased with age and varied with the species and season. We founded differences among forage grass and legume species under field conditions to form symbiosis with mycorrhizal fungi. Knowledge on these interspecific differences could contribute to developing better adapted forage systems to contribute recuperating the degraded soils of the Andean hillsides of Latin America.

  7. Ocorrência de micorrizas arbusculares e da bactéria diazotrófica Acetobacter diazotrophicus em cana-de-açúcar Occurrence of arbuscular mycorrhizae and bacterium Acetobacter diazotrophicus in sugar cane

    Directory of Open Access Journals (Sweden)

    Veronica Massena Reis

    1999-10-01

    Full Text Available Foi avaliada a ocorrência e a distribuição de espécies de fungos micorrízicos arbusculares (FMAs e Acetobacter diazotrophicus em plantios de cana-de-açúcar em diferentes tipos de manejo nos Estados do Rio de Janeiro e Pernambuco. Foram feitas 35 coletas de amostras de solo da rizosfera e de raízes de 14 variedades de cana-de-açúcar para extração de esporos e isolamento da bactéria. O número de esporos variou de 18 a 2.070/100 mL de solo, e os maiores número e diversidade de espécies foram verificados nos canaviais de Campos, RJ, especialmente naqueles que não adotam a queima do palhiço. As espécies predominantes nas três localidades amostradas foram: Acaulospora sp., Scutellospora heterogama, Glomus etunicatum, Glomus occultum e Gigaspora margarita. A. diazotrophicus estava presente nas amostras de raízes colhidas em canaviais de Campos, com exceção de uma coleta de cana-de-açúcar plantada num solo usado como bacia de sedimentação de vinhaça. Não foi possível isolar essa bactéria a partir de esporos desinfestados dos FMAs nativos, apenas dos esporos lavados com água estéril.The occurrence and distribution of species of arbuscular mycorrhizae fungi and Acetobacter diazotrophicus in sugar cane (Saccharum officinarum grown in different regimes of crop management in the States of Rio de Janeiro and Pernambuco, Brazil, were studied. Thirty five samples of the rhizosphere soil and roots were collected from 14 varieties of sugar cane for the extraction of spores and isolation of the bacterium. The number of spores varied from 18 to 2,070 per 100 mL of soil, and the greatest diversity of fungal species was found in the sugarcane fields of Campos (Rio de Janeiro State, especially in those where the sugarcane trash was not burned at harvest. The predominant species found in the three localities sampled were: Scutellospora heterogama, Glomus etunicatum, Glomus occultum, Acaulospora sp. and Gigaspora margarita. A

  8. Influência da colonização micorrízica arbuscular sobre a nutrição do quiabeiro Influence of arbuscular mycorrhiza fungi on the nutrition of okra plant

    Directory of Open Access Journals (Sweden)

    Ricardo Luís Louro Berbara

    1999-09-01

    Full Text Available Foram estudados em casa de vegetação alguns parâmetros de crescimento em plantas de quiabo (Abelmoschus esculentus (L. Moench cv. Piranema colonizadas por dois grupos de fungos micorrízicos arbusculares, com o objetivo de determinar a influência dos inóculos na nutrição e morfologia radicular do quiabeiro. Um grupo continha apenas esporos de Acaulospora longula (A enquanto o outro, esporos de oito espécies: Glomus occultum, Glomus aggregatum, Glomus microcarpum, Acaulospora longula, Acaulospora morrowae, Sclerocystis coremioides, Sclerocystis sinuosa, Scutellospora pellucida. As plantas foram submetidas a três níveis de P (0, 10 e 60 kg ha-1 de P2O5 e coletadas em três diferentes idades (22, 32 e 47 dias, com quatro repetições para cada tratamento. Foi determinado o acúmulo de N, P, K, e Mg na raiz e parte aérea, bem como o influxo médio desses elementos e a área radicular. Os resultados indicaram, além da resposta positiva do quiabeiro ao P, uma maior eficiência da inoculação com mistura de espécies apesar de o influxo médio, determinado aos 47 dias, apresentar maiores valores para o tratamento com A. longula.An experiment was carried out in greenhouse to determine the influence of inoculation of two groups of arbuscular mycorrhizae on the nutrition and radicular morphology of the okra plant (Abelmoschus esculentus (L. Moench cv. Piranema. One group had only Acaulospora longula spores and the other a spore mixture of eight species: Glomus occultum, Glomus aggregatum, Glomus microcarpum, Acaulospora longula, Acaulospora morrowae, Sclerocystis coremioides, Sclerocystis sinuosa, Scutellospora pellucida. The experiment was held in greenhouse conditions with three levels of P (0, 10 and 60 kg ha-1 of P2O5, three samplings dates (22, 32 and 47 days and four replications. The accumulation of N, P, K, Ca and Mg in roots and shoots, root area and their influx ratio were determined. The results made evident that the mixture of

  9. Unraveling the signaling and signal transduction mechanisms controlling arbuscular mycorrhiza development Desenredando os mecanismo de sinalização e transdução de sinais que controlam o desenvolvimento de micorrizas arbusculares

    Directory of Open Access Journals (Sweden)

    Marcio Rodrigues Lambais

    2006-08-01

    Full Text Available Arbuscular mycorrhiza (AM are the most widespread symbiotic associations between plant roots and soil fungi. AM can contribute to increasing the survival and fitness of plants to limiting environments mostly due to their ability in improving nutrient uptake from the soil solution. Despite their ecological significance, the mechanisms controlling AM development and functioning are largely unknown. The obligate mutualistic nature of the arbuscular mycorrhizal fungi (AMF has hampered the advances on the understanding and application of the symbiosis. Significant alterations in the genetic programs of both symbionts are required for the successful establishment of an AM, and complex signaling and signal transduction mechanisms are likely involved. The analyses of legume mutants affected in the development of nitrogen fixing nodules and AM suggest that part of the signal transduction pathways involved in the regulation of both symbioses are conserved. Even though the use of genomics of model plants has helped to advance our understanding of the regulatory mechanisms in AM, identifying the signal molecules involved in plant-AMF communication and determining their transduction pathways is still essential for its biotechnological application in agriculture.As micorrizas arbusculares (MAs são as associações simbióticas entre raízes de plantas e fungos mais comuns na natureza. Elas podem contribuir para o aumento da sobrevivência e adaptação das plantas a ambientes limitantes, principalmente devido a sua maior capacidade em absorver nutrientes da solução do solo. Apesar de sua importância ecológica, os mecanismos que controlam o desenvolvimento e fisiologia das MAs são pouco conhecidos. A natureza mutualística obrigatória dos fungos micorrízicos arbusculares (FMAs tem limitado os avanços na compreensão e aplicação da simbiose. Alterações significativas nos programas genéticos de ambos simbiontes são necessárias para o

  10. Micorriza arbuscular e rizóbios no enraizamento e nutrição de mudas de angico-vermelho Arbuscular mycorrhizae and rhizobium in rooting and nutrition of angico-vermelho seedlings

    Directory of Open Access Journals (Sweden)

    Poliana Coqueiro Dias

    2012-12-01

    Full Text Available O objetivo deste estudo foi avaliar o efeito da inoculação dos fungos micorrízicos arbusculares (FMAs e rizóbio no enraizamento, crescimento e nutrição de mudas de angico-vermelho (Anadenanthera macrocarpa (Benth Brenan propagadas via miniestaquia. Foram utilizadas seis progênies, das quais foram confeccionadas miniestacas com um par de folhas inteiras, bem como tubetes de 55 cm³ contendo substrato comercial Bioplant®. Foram testados quatro tratamentos: 8 kg m-3 de superfosfato simples (SS misturados ao substrato; 4 kg m-3 de SS misturados ao substrato; 4 kg m-3 de SS misturados ao substrato e adição de suspensão contendo rizóbios; e 4 kg m-3 de SS e adição de suspensão contendo rizóbios e 5 g de solo contendo esporos de FMAs. Não houve interação entre os tratamentos para percentagem de sobrevivência das miniestacas e percentagem de miniestacas com raízes observadas na extremidade inferior do tubete, na saída da casa de vegetação (30 dias e da casa de sombra (40 dias, provavelmente em função do sistema radicular ainda estar em formação. Houve diferenças entre as progênies para percentagem de sobrevivência das miniestacas, percentagem de miniestacas com raízes observadas na extremidade inferior do tubete, altura, diâmetro de colo e massa seca da parte aérea. As avaliações das características de crescimento das miniestacas enraizadas, principalmente com relação à sobrevivência a pleno sol (140 dias, evidenciam a eficiência dos rizóbios e FMAs na produção de mudas desta espécie. Conclui-se que a associação simbiótica com rizóbio e/ou FMA favorece a produção de mudas de A. macrocarpa via miniestaquia.The objective of this study was to evaluate the effect of inoculation of arbuscular mycorrhizae fungi (AMF and rhizobium on rooting, growth and nutrition of seedlings of angico-red (Anadenanthera macrocarpa (Benth Brenan propagated by minicutting. Six progenies were used, of which were prepared

  11. Oaks belowground: mycorrhizas, truffles, and small mammals

    Science.gov (United States)

    Jonathan Frank; Seth Barry; Joseph Madden; Darlene Southworth

    2008-01-01

    Oaks depend on hidden diversity belowground. Oregon white oaks (Quercus garryana) form ectomycorrhizas with more than 40 species of fungi at a 25-ha site. Several of the most common oak mycorrhizal fungi form hypogeous fruiting bodies or truffles in the upper layer of mineral soil. We collected 18 species of truffles associated with Oregon white...

  12. (ajst) response of meloidogyne hapla to mycorrhiza

    African Journals Online (AJOL)

    opiyo

    The presence of nematodes in fungus-treated plants did not affect root colonization by the fungi except in plants treated ... pyrethrum yield losses, a decrease in flower size and pyrethrin content, stunting, chlorosis, wilting .... nutrient solution (12%N, 4% P2O5, 6%K2O, 0.02% Boron and 0.01% Copper) monthly. Meloidogyne ...

  13. Plant nutrient transporter regulation in arbuscular mycorrhizas

    DEFF Research Database (Denmark)

    Burleigh, Stephen; Bechmann, I.E.

    2002-01-01

    This review discusses the role arbuscular mycorrhizal fungi play in the regulation of plant nutrient transporter genes. Many plant nutrient transporter genes appear to be transcriptionally regulated by a feed-back mechanism that reduces their expression when the plant reaches an optimal level...... of nutrition. Their down-regulation in mycorrhizal roots, therefore, would be predicted as a result of symbiotic function. A variety of studies on Pi- Zn- and ammonium- or nitrate-transporter genes from two plant species indirectly support this model. For example, one study showed that the expression...... of the high-affinity Pi-transporter MtPT2 within mycorrhizal roots of Medicago truncatula was inversely correlated with the concentration of P within the shoots, which suggested that P supply from the fungus influenced this gene's expression. However, there is some evidence that these plant nutrient...

  14. [Arbuscular mycorrhizae in Paris polyphylla var. yunnanensis].

    Science.gov (United States)

    Zhou, Nong; Xia, Conglong; Jiang, Bei; Bai, Zhichuan; Liu, Guangming; Ma, Xiaokuang

    2009-07-01

    To study the infection situation of arbuscular mycorrhizal fungi, as well as the mycorrhizal structures of Paris polyphylla var. yunnanensis, and the main types and quantities of AMF spores in rhizosphere soil. The arbuscular mycorrhizal of P. polyphylla var. yunnanensis were detected by Phillips and Hayman staining. At the same time, some AMF spores were accessed by Gendemann's Wet-screening method and identified by their morphological characteristics. Arbuscular mycorrhizal fungi could infect the roots of P. polyphylla var. yunnanensis and formed arbuscular mycorrhizal. Infection rate was from 35.3% to 98.6%, indicating that infection strength was strong. From 10 soil samples collected in Yunnan, 11 Acaulospor species, 7 Glomus species, 3 Gigaspora species and 3 Scutellospora species were isolated and identified, including Acaulospora appendicola, A. brieticulata, A. excavata, A. foveata, A. lacunosa, A. laevis, A. koskei, A. myriocarpa, A. polonica, A. rehmii, A. scrobiculata, Glomus albidum, G. ambisporum, G. deserticola, G. fragarioides, G. luteum, G. microaggregatum, G. multiforum, Gigaspora albida, G. margarita, G. ramisporophora, Scutellospora calospora, S. pellucida and S. gilmorei. Among them, Acaulospora brieticulata was advantage species. AMF may be a potent biological resource which can stimulate the growth of P. polyphylla var. yunnanensis.

  15. Micorriza arbuscular e nutrição fosfática na toxidez de zinco para a trema [Trema micrantha (L. Blum.] Arbuscular mycorrhiza and phosphorus nutrition on zinc toxicity to trema [Trema micrantha (L. Blum.

    Directory of Open Access Journals (Sweden)

    Cláudio Roberto Fonsêca Sousa Soares

    2006-08-01

    mycorrhiza, the plant P nutritional status and increasing levels of P in nutrient solution on Zn toxicity to Trema micrantha (L. Blum. In a first experiment trema seedlings were grown in a substrate with increasing P rates [0, 100, 200 and 400 mg dm-3 as Ca(H2PO42], besides a mycorrhizal treatment inoculated with Glomus etunicatum (Ge. After 60 days of growth, the plants were transferred to pots with Clark's nutrient solution containing 2, 75, 150 and 225 µmol L-1 of Zn, grown for 40 days, harvested and evaluated. In a second experiment the ameliorating effects of P on Zn phytotoxicity were also evaluated in nutrient solution containing increasing P rates (0.07; 0.5; 1 and 2 mmol L-1 supplied by different sources and Zn (2, 75, 150 and 225 µmol L-1 as ZnSO4.7H2O combined and simultaneously applied to the solution where trema seedlings were left to grow for 40 days. It was found that high Zn concentrations were highly inhibitory to plant growth and mycorrhizal colonization. Enhanced P nutrition reduced translocation of Zn from plant roots to shoots, but such effects as well as mycorrhizal colonization had no effect on trema growth under Zn excess in solution. In the second experiment, higher P concentration in solution improved the plant nutritional status and protected them against the excess of Zn. Considering that chemical speciation of the solution showed no significant effect on Zn forms, the results suggested that the ameliorating effects of P occur within the plant (in planta, possibly by reducing Zn translocation from roots to shoots.

  16. EFECTO DE LA MICORRIZA Y GALLINAZA SOBRE LA PRODUCCIÓN Y LA CALIDAD DE CEBOLLA CABEZONA (Allium cepa L. ‘Yellow Granex’ EFFECT OF MYCORRHIZAE AND HEN MANURE FERTILIZATION ON YIELD AND QUALITY OF ONION (Allium cepa L. ‘YELLOW GRANEX’

    Directory of Open Access Journals (Sweden)

    Maritza Yolima Agudelo Becerra

    2004-06-01

    Full Text Available En condiciones de campo se evaluó el efecto de hongos micorrizógenos y de gallinaza, comparado con la aplicación de fertilizante mineral, sobre la producción y la calidad de cebolla cabezona (Allium cepa L. ‘Yellow Granex’ en el municipio de Cucaita - Boyacá (Colombia. Las semillas germinaron en suelo, y 70 días después de la germinación, se seleccionaron plántulas de tamaño uniforme, se transplantaron y se inocularon (0,86 ton/ha de Mycofertil o no con hongos micorrícicos. Se aplicaron tres dosis de gallinaza (0 - 1 y 2 ton/ha y 0,5 ton / ha de fertilizante comercial 15 - 15 - 15. Se evaluó la producción total, la producción de bulbos de primera y segunda calidad, así como de los bulbos dañados. Se utilizó el diseño de bloques al azar con tres replicaciones. Se hizo un análisis de varianza (ANOVA para los datos registrados y se realizó la prueba de comparación de medias de Duncan con un nivel de significancia de 0,01. Los resultados mostraron que las micorrizas y la gallinaza incrementaron la producción total y de las cebollas de primera calidad, comparados con la aplicación fertilizante mineral solo o complementado con 1 ó 2 ton/ha de gallinaza. Sin embargo, la producción de cebolla de segunda calidad fue superior en las parcelas tratadas con micorrizas, comparadas con los otros tratamientos sin ellas. Por otro lado, la adición de micorrizas redujo la cantidad de bulbos dañados. El tratamiento con fertilizante mineral solo presentó la producción total más baja y la menor producción de cebolla de primera y segunda calidad, pero la más alta producción de cebollas dañadas, en comparación con los demás tratamientos evaluados. Los resultados se discutieron con base en el incremento en la toma de nutrientes y en la reducción del efecto de patógenos radiculares en las plantas colonizadas con micorrizas.Under field conditions, the effects of mycorrhizae and hen manure fertilization, compared to the application

  17. Browse Title Index

    African Journals Online (AJOL)

    Items 3951 - 4000 of 11090 ... Vol 10, No 36 (2011), Effect of vermicompost on manifestation of pesticide action on growth of Zinnia elegans, Abstract PDF. AK Sharan, M Kumar, R Singh, AK Neha, GD Sharma, C Jee. Vol 7, No 19 (2008), Effect of vesicular arbuscular mycorrhizal fungus on the physiological and biochemical ...

  18. Browse Title Index

    African Journals Online (AJOL)

    Items 151 - 200 of 444 ... Vol 24 (1991), Effects of nitrate and ammonium nitrogen on vesicular-arbuscular mycorrhizal infection in letttuce (Lactuca sativa) grown in sand with nutrient solutions, Abstract. E Owusu-Benoah. Vol 20 (1987), Effects of N-nitrate fertilization on yield and dinitrogen fixation in common bean (Phaseolus ...

  19. Author Details

    African Journals Online (AJOL)

    Owusu-Benoah, E. Vol 24 (1991) - Articles Effects of nitrate and ammonium nitrogen on vesicular-arbuscular mycorrhizal infection in letttuce (Lactuca sativa) grown in sand with nutrient solutions. Abstract. ISSN: 0855-0042. AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors ...

  20. Influence of mycorhization and soil organic matters on lead and antimony transfers to vegetables cultivated in urban gardens: environmental and sanitary consequences

    Science.gov (United States)

    Pierart, Antoine; Braud, Armelle; Lebeau, Thierry; Séjalon-Delmas, Nathalie; Dumat, Camille

    2014-05-01

    . References: Feng, R., Wei, C., Tu, S., Ding, Y., Wang, R., Guo, J., 2013. The uptake and detoxification of antimony by plants: a review. Environ. Exp. Bot. 96, 28-34. Foucault, Y., Lévêque, T., Xiong, T., Schreck, E., Austruy, A., Shahid, M., Dumat, C., 2013. Green manure plants for remediation of soils polluted by metals and metalloids: Ecotoxicity and human bioavailability assessment. Chemosphere 93, 1430-1435. Gu, H.H., Li, F.P., Yu, Q., Gao, Y.Q., Yuan, X.T., 2013. The Roles of Arbuscular Mycorrhizal Fungus Glomus mosseae and Festuca arundinacea in Phytostabilization of Lead/Zinc Tailings. Adv. Mater. Res. 699, 245-250. Lebeau, T., Braud, A., Jézéquel, K., 2008. Performance of bioaugmentation-assisted phytoextraction applied to metal contaminated soils: A review. Environ. Pollut. 153, 497-522. Sharma, A., Sharma, H., 2013. Role of Vesicular Arbuscular Mycorrhiza in the Mycoremediation of Heavy Toxic Metals From Soil. Int J LifeSc Bt Pharm Res 2, 2418-2431. Wu, F., Fu, Z., Liu, B., Mo, C., Chen, B., Corns, W., Liao, H., 2011. Health risk associated with dietary co-exposure to high levels of antimony and arsenic in the world's largest antimony mine area. Sci. Total Environ. 409, 3344-3351. Xiong, T., Austruy, A., Dappe, V., Leveque, T., Sobanska, S., Foucault, Y., Dumat, C., 2013. Phytotoxicity and bioaccessibility of metals for vegetables exposed to atmosphere fine particles in polluted urban areas". Urban Environmental Pollution, Asian Edition, 17-20, Beijing, China.

  1. Mycorrhizae on dipterocarps in rubber agroforests (RAF) in Sumatra

    NARCIS (Netherlands)

    Tata, M.H.L.

    2008-01-01

    In tropical lowland forests, which dominated by trees of Dipterocarpaceae family, trees and fungi are strongly linked, through ectomycorrhiza (EcM) formation. However, as part of rapid deforestation and forest transformation, mixed dipterocarp forests have been replaced by other vegetation and land

  2. Role of mycorrhizae in forestation of surface mines

    Science.gov (United States)

    Donald H. Marx

    1980-01-01

    A brief introduction to ecto- and endomycorrhizae and their importance to plants is presented. Recent findings confirm the significance of ectomycorrhizae, particularly those formed by Pisolithus tinctorius in nurseries, to survival and growth of pine seedlings on strip-mined lands. Commercial inoculum of this fungus may be available in 1981. Recent...

  3. Effects of arbuscular mycorrhizae on microbial population and ...

    African Journals Online (AJOL)

    , and the activities of soil proteinase, polyphenoloxidase, urease, and saccharase in replant soils gradually declined, while the fungal population, and the fungi/total microbe ratio increased, as replanting years rose. In each replant soil, the ...

  4. Arbuscular mycorrhiza contribution to the growth performance and ...

    African Journals Online (AJOL)

    hope&shola

    2009-06-12

    Jun 12, 2009 ... Key words: Glomus mosseae, Glomus intraradices, Helianthus annuus, phytoremediation, polluted soil. INTRODUCTION. Soil contamination due to the disposal of industrial and urban wastes generated by human activities has become a major environmental concern. Controlled and uncon- trolled disposal ...

  5. Arbuscular mycorrhizae of dominant plant species in Yungas forests, Argentina.

    Science.gov (United States)

    Becerra, Alejandra G; Cabello, Marta; Zak, Marcelo R; Bartoloni, Norberto

    2009-01-01

    In Argentina the Yungas forests are among the ecosystems most affected by human activity, with loss of biodiversity. To assess the arbuscular mycorrhizal (AM) colonization and the arbuscular mycorrhizal fungi (AMF) spore numbers in these ecosystems, the roots of the most dominant native plants (one tree, Alnus acuminata; three herbaceous, Duchesnea indica, Oxalis conorrhiza, Trifolium aff. repens; and one shrub, Sambucus peruviana) were studied throughout the year from two sites of Yungas forests. Assessments of mycorrhizal colonization (percent root length, intraradical structures) were made by washing and staining the roots. Soil samples of each plant species were pooled and subsamples were obtained to determine AM spore numbers. The herbaceous species formed both Arum- and Paris-type morphologies, whereas the tree and the shrub species formed respectively single structural types of Arum- and Paris-type. AM colonization, intraradical fungi structures and AMF spore numbers displayed variation in species, seasons and sites. D. indica showed the highest AM colonization, whereas the highest spore numbers was observed in the rhizosphere of A. acuminata. No correlation was observed between spore numbers and root length percentage colonized by AM fungi. Results of this study showed that Alnus acuminata is facultatively AM. The AM colonization, intraradical fungi structures and AMF spore numbers varied in species depending on phenological, climatic and edaphic conditions.

  6. Use of arbuscular mycorrhiza fungi for improved crop production in ...

    African Journals Online (AJOL)

    Soil fertility depletion through crop removal, soil erosion and leaching is a major challenge to increased crop productivity in Sub-Saharan Africa. Whereas nitrogen can be replenished using Rhizobium inoculants and growing leguminous crops, P is difficult to replenish. This is due to the high fixing capacity of most soils in ...

  7. Miombo trees and mycorrhizae : ecological strategies, a basis for afforestation

    NARCIS (Netherlands)

    Munyanziza, E.

    1994-01-01

    This project has covered one or several aspects of the life cycle of the main miombo tree species, namely Afzelia quanzensis ,Brachystegia microphylla, Brachystegia spiciformis

  8. Miombo trees and mycorrhizae : ecological strategies, a basis for afforestation

    OpenAIRE

    Munyanziza, E.

    1994-01-01

    This project has covered one or several aspects of the life cycle of the main miombo tree species, namely Afzelia quanzensis ,Brachystegia microphylla, Brachystegia spiciformis ,Julbernardia globifloraand Pterocarpus angolensis . These aspects included natural and artificial regeneration,...

  9. Tillage or no-tillage: Impact on mycorrhizae

    OpenAIRE

    Kabir, Zahangir

    2005-01-01

    Arbuscular mycorrhizal (AM) fungi are ubiquitous in agricultural soils. These fungi play important roles in plant nutrition and soil conservation. The persistence of AM fungi in ecosystems depends on the formation and survival of propagules (e.g., spore, hyphae and colonized roots). While spores are considered to be resistant structure that may be view as "long-term" propagules when viable host plants are not present, hyphae are considered to be the main source of inocula when host plants are...

  10. Effects of arbuscular mycorrhiza and composted market waste on ...

    African Journals Online (AJOL)

    International Journal of Biological and Chemical Sciences. Journal Home · ABOUT · Advanced Search · Current Issue · Archives · Journal Home > Vol 8, No 3 (2014) >. Log in or Register to get access to full text downloads.

  11. Effects of Moisture and Mycorrhiza on Stomatal Conductance and ...

    African Journals Online (AJOL)

    A complete randomized block design with five replications and factorical combination of three watering regimes (daily for unstressed plant, twice weekly for partially stressed plants and once a week for moisture stressed plants) and three mycorrhizal treatments namely; endomycorrhizal plants, ectomycorrhizal plants and ...

  12. Effects of Mycorrhiza on the Growth and Productivity of Faidherbia ...

    African Journals Online (AJOL)

    A complete randomized block design with five replications and factorial combination of three watering regimes (daily for unstressed plant, twice weekly for partially stressed plants and once a week for moisture stressed plants) and three mycorrhizal treatments namely; endomycorrhizal plants, ectomycorrhizal plants and non ...

  13. Effects of light limitation on legume-mycorrhizae interactions.

    OpenAIRE

    Millar, Jess; Ballhorn, Daniel

    2014-01-01

    Plants respond with a sink stimulation of photosynthesis when colonized by fungal mutualists, which compensates for costs of carbohydrate allocation to the microbes. Problems may arise when light is limited and plants cannot increase photosynthesis. We hypothesize that under such conditions the costs for maintaining the mutualism outweigh the benefits, which ultimately turns the beneficial microbes into parasites exploiting resources and reducing host fitness. We study these plant-microbe int...

  14. Lead (Pb) uptake (mediated by Arbuscular Mycorrhiza) from Soil ...

    African Journals Online (AJOL)

    The need to increase cowpea production for the increasing population in cities had led to cultivation of available land in city centres for farming regardless of the level of heavy metal pollution of such land. It has therefore become imperative to assess this practice with the aim of identifying the level of danger inherent in the ...

  15. Plant 9-lox oxylipin metabolism in response to arbuscular mycorrhiza.

    Science.gov (United States)

    León Morcillo, Rafael Jorge; Ocampo, Juan A; García Garrido, José M

    2012-12-01

    The establishment of an Arbuscular Mycorrhizal symbiotic interaction (MA) is a successful strategy to substantially promote plant growth, development and fitness. Numerous studies have supported the hypothesis that plant hormones play an important role in the recognition and establishment of symbiosis. Particular attention has been devoted to jasmonic acid (JA) and its derivates, the jasmonates, which are believed to play a major role in AM symbiosis. Jasmonates belong to a diverse class of lipid metabolites known as oxylipins that include other biologically active molecules. Recent transcriptional analyses revealed upregulation of the oxylipin pathway during AM symbiosis in mycorrhizal tomato roots and point a key regulatory feature for oxylipins during AM symbiosis in tomato, particularly these derived from the action of 9-lipoxygenases (9-LOX). In this mini-review we highlight recent progress understanding the function of oxylipins in the establishment of the AM symbiosis and hypothesize that the activation of the 9-LOX pathway might be part of the activation of host defense responses which will then contribute to both, the control of AM fungal spread and the increased resistance to fungal pathogens in mycorrhizal plants.

  16. High specificity in plant leaf metabolic responses to arbuscular mycorrhiza.

    Science.gov (United States)

    Schweiger, Rabea; Baier, Markus C; Persicke, Marcus; Müller, Caroline

    2014-05-22

    The chemical composition of plants (phytometabolome) is dynamic and modified by environmental factors. Understanding its modulation allows to improve crop quality and decode mechanisms underlying plant-pest interactions. Many studies that investigate metabolic responses to the environment focus on single model species and/or few target metabolites. However, comparative studies using environmental metabolomics are needed to evaluate commonalities of chemical responses to certain challenges. We assessed the specificity of foliar metabolic responses of five plant species to the widespread, ancient symbiosis with a generalist arbuscular mycorrhizal fungus. Here we show that plant species share a large 'core metabolome' but nevertheless the phytometabolomes are modulated highly species/taxon-specifically. Such a low conservation of responses across species highlights the importance to consider plant metabolic prerequisites and the long time of specific plant-fungus coevolution. Thus, the transferability of findings regarding phytometabolome modulation by an identical AM symbiont is severely limited even between closely related species.

  17. Agroecology: the key role of arbuscular mycorrhizas in ecosystem services.

    Science.gov (United States)

    Gianinazzi, Silvio; Gollotte, Armelle; Binet, Marie-Noëlle; van Tuinen, Diederik; Redecker, Dirk; Wipf, Daniel

    2010-11-01

    The beneficial effects of arbuscular mycorrhizal (AM) fungi on plant performance and soil health are essential for the sustainable management of agricultural ecosystems. Nevertheless, since the 'first green revolution', less attention has been given to beneficial soil microorganisms in general and to AM fungi in particular. Human society benefits from a multitude of resources and processes from natural and managed ecosystems, to which AM make a crucial contribution. These resources and processes, which are called ecosystem services, include products like food and processes like nutrient transfer. Many people have been under the illusion that these ecosystem services are free, invulnerable and infinitely available; taken for granted as public benefits, they lack a formal market and are traditionally absent from society's balance sheet. In 1997, a team of researchers from the USA, Argentina and the Netherlands put an average price tag of US $33 trillion a year on these fundamental ecosystem services. The present review highlights the key role that the AM symbiosis can play as an ecosystem service provider to guarantee plant productivity and quality in emerging systems of sustainable agriculture. The appropriate management of ecosystem services rendered by AM will impact on natural resource conservation and utilisation with an obvious net gain for human society.

  18. The role of mycorrhizae in afforestation (a review).

    Science.gov (United States)

    Barna, T

    2002-01-01

    Hungary is facing to perform intensive afforestation. New forests will be planted on dry, poorly fertile soils nonprofitable for agricultural use. Applying artificially mycorrhized seedlings may considerably increase the effectivity of afforestation and decrease costs.

  19. Cereal mycorrhiza: an ancient symbiosis in modern agriculture.

    Science.gov (United States)

    Sawers, Ruairidh J H; Gutjahr, Caroline; Paszkowski, Uta

    2008-02-01

    The majority of terrestrial plants live in association with symbiotic fungi that facilitate mineral nutrient uptake. The oldest and most prevalent of these associations are the arbuscular mycorrhizal (AM) symbioses that first evolved approximately 400 million years ago, coinciding with the appearance of the first land plants. Crop domestication, in comparison, is a relatively recent event, beginning approximately 10000 years ago. How has the dramatic change from wild to cultivated ecosystems impacted AM associations, and do these ancient symbioses potentially have a role in modern agriculture? Here, we review recent advances in AM research and the use of breeding approaches to generate new crop varieties that enhance the agronomic potential of AM associations.

  20. Dipterocarpaceae: Shorea leprosula Miq. cuttings, mycorrhizae and nutrients

    NARCIS (Netherlands)

    Mulyana Omon, R.

    2002-01-01

    "Dipterocarpaceae: Shorea leprosula cuttings, mycorrhizace and nutrients" discusses the mycorrhizal development in conditions of different dosage of NPK fertilizer, on different soil substrates and under different environmental conditions

  1. Mycorrhizas and global environmental change: Research at different scales

    DEFF Research Database (Denmark)

    Staddon, P.L.; Heinemeyer, A.; Fitter, A.H.

    2002-01-01

    Global environmental change (GEC), in particular rising atmospheric CO2 concentration and temperature, will affect most ecosystems. The varied responses of plants to these aspects of GEC are well documented. As with other key below-ground components of terrestrial ecosystems, the response of the ...

  2. Community-level consequences of mycorrhizae depend on phosphorus availability.

    Science.gov (United States)

    Collins, Cathy D; Foster, Bryan L

    2009-09-01

    In grasslands, arbuscular mycorrhizal fungi (AMF) mediate plant diversity; whether AMF increase or decrease diversity depends on the relative mycotrophy in dominant vs. subordinate plants. In this study we investigated whether soil nutrient levels also influence the ability of AMF to mediate plant species coexistence. First, we developed a conceptual model that predicts the influence of AMF on diversity along a soil nutrient gradient for plant communities dominated by mycotrophic and non-mycotrophic species. To test these predictions, we manipulated phosphorus to create a soil nutrient gradient for mesocosm communities composed of native prairie grasses and then compared community properties for mesocosms with and without AMF. We found that, where P was limiting, AMF increased plant diversity and productivity, and also altered community structure; however, at high P, AMF had little influence on aboveground communities. Compositional differences among treatments were due largely to a trade-off in the relative abundance of C3 vs. C4 spes. Our study emphasizes how environmental constraints on mutualisms may govern community- and ecosystem-level properties.

  3. VINEYARD FLOOR MANAGEMENT HAS MINIMAL EFFECTS ON MYCORRHIZAE

    Science.gov (United States)

    Arbuscular mycorrhizal fungi (AMF) are one of few groups of soil microbes that have been shown to benefit grapevine nutrition. Grapevines respond positively to AMF, as evidenced by increased growth with inoculation. Furthermore, their low root density and coarse root texture reflect their relative...

  4. Mycorrhiza in tropical agriculture | Owusu-Bennoah | Ghana Journal ...

    African Journals Online (AJOL)

    Ghana Journal of Agricultural Science. Journal Home · ABOUT · Advanced Search · Current Issue · Archives · Journal Home > Vol 24 (1991) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register. DOWNLOAD FULL TEXT Open Access DOWNLOAD FULL TEXT ...

  5. Nucleic acid isolation from ecological samples--fungal associations, mycorrhizae.

    Science.gov (United States)

    Koide, Roger T

    2005-01-01

    Mycorrhizal fungi are among the most common symbioses found in terrestrial ecosystems, both natural and managed. They are important for many reasons, but most notably because of their positive effects on plant growth, which are mediated by their uptake of nutrients from the soil and transport of these to the roots. Moreover, many edible fungi are mycorrhizal. The study of mycorrhizal fungi has been hampered by the inability to identify species and individuals in the soil. This has been greatly aided by DNA-based methods, which first require the extraction of DNA. Herein, I discuss some general concerns that must be considered when extracting and purifying DNA from ecological samples and offer specific methods for soil, mycorrhizal roots, and fruiting bodies. These methods are rapid, safe, effective, relatively inexpensive, and convenient because they are based on commercially available kits.

  6. Does responsiveness to arbuscular mycorrhizas depend on plant invasive status?

    Science.gov (United States)

    1. Some posit invasive alien plants are less dependent on mycorrhizal associations than native plants, and thus weak mycorrhizal responsiveness may be a general mechanism of plant invasion. 2. Here, we tested whether mycorrhizal responsiveness varies by plant invasive status while controlling for ph...

  7. MULTIPLICACIÓN DE HONGOS MICORRIZA ARBUSCULAR (H.M.A Y EFECTO DE LA MICORRIZACIÓN EN PLANTAS MICROPROPAGADAS DE BANANO (Musa AAA cv. Gran Enano (Musaceae MULTIPLICATION OF ARBUSCULAR MYCORRHIZAE FUNGI (AMF AND MYCORRHIZATION EFFECT IN MICROPROPAGATED PLANTS OF BANANA (Musa AAA cv. ‘Gran Enano’ (Musaceae

    Directory of Open Access Journals (Sweden)

    Carmen Elena Usuga Osorio

    2008-06-01

    Full Text Available Se evaluó el proceso de multiplicación de hongos que forman micorriza arbuscular (HMA, para lo cual se usaron diferentes tipos de inóculos entre ellos nativos de agroecosistemas bananeros del Urabá (Antioquia-Colombia, en sustrato sólido, con diferentes plantas hospedadoras y la infectividad y efectividad sobre plantas de banano (Musa AAA cv. Gran Enano. La colonización micorrizal promedio general de los HMA a las plantas trampa fue de 37,76 ± 21,86 %, con respecto a este porcentaje, las plantas B (Brachiaria decumbens y S (Sorgum vulgare fueron las que más favorecieron la simbiosis. Teniendo en cuenta el sustrato, el S2 (Arena 50 - suelo 50 y el S6 (Vermiculita 50-suelo 50 permitieron expresiones significativamente mayores respecto a los demás. El Sorgum vulgare y Pueraria phaseoloides y en el sustrato S1 (Arena 30 - suelo 70, se encontró un mayor número de esporas. La combinación planta-sustrato que más favoreció la asociación fue la planta trampa B en los sustratos S2 y S4 (cascarilla de arroz 50-suelo50 y la producción de esporas fueron las plantas K y S en el sustrato S1. La asociación micorrícica general en plantas de banano provenientes de cultivo de tejidos fue de 48,74 ± 30,44. No se encontraron diferencias significativas (P > 0,05 entre plantas de cero días con plantas de 30 de aclimatadas. Los inóculos que significativamente favorecieron la asociación fueron los provenientes de agroecosistemas bananeros al compararse con el inóculo comercial y el proveniente de ecosistemas naturales del Urabá. El mayor peso seco foliar y radical se encontró en plántulas de banano inoculadas con I5 (Inóculo proveniente de agroecosistema bananeros de la zona de estudio. Para las variables de crecimiento no se encontraron diferencias.The process of multiplication of arbuscular mycorrhizae fungi (AMF from indigenous banana agro-environments from Urabá (Antioquia - Colombia was evaluated, using solid substrate, with different

  8. Nutrição fosfática e micorriza arbuscular na redução da toxicidade de cádmio em trema [Trema micrantha (L. Blum.] Phosphate nutrition and arbuscular mycorrhiza on amelioration of cadmium toxicity in trema [Trema micrantha (L. Blum.

    Directory of Open Access Journals (Sweden)

    Cláudio Roberto Fonsêca Sousa Soares

    2007-10-01

    Full Text Available Neste trabalho, avaliaram-se os efeitos da nutrição fosfática e da micorriza arbuscular na toxicidade de Cd em Trema micrantha (L. Blum. Em um primeiro experimento, mudas de trema foram formadas em substrato contendo doses crescentes de P (0, 100, 200 e 400 mg dm-3 e com um tratamento de inoculação com Glomus etunicatum. Após crescimento por 60 dias, essas mudas foram transferidas para solução nutritiva de Clark sem Cd e suplementada com 5, 15 e 45 µmol L-1 de Cd e mantidas por mais 40 dias, quando os efeitos dos tratamentos foram avaliados. As influências do P na amenização da fitotoxidez de Cd foram também avaliados em outro experimento, aplicando-se simultaneamente e de forma combinada em solução, doses de P (0,07; 0,5; 1; e 2 mmol L-1 e de Cd (0, 5, 10 e 15 µmol L-1. Houve acentuada inibição no crescimento e colonização micorrízica da trema mesmo na dose mais baixa de Cd em solução (5 µmol L-1. Constatou-se que a melhoria da nutrição fosfática favoreceu o crescimento da planta, sendo isso associado à redução da toxicidade de Cd, enquanto a inoculação com G. etunicatum não teve o mesmo efeito. Encontrou-se uma relação inversa entre o aumento no fornecimento de P em solução e a absorção e acúmulo de Cd na trema. Análise da especiação química da solução indicou que o P não interferiu na disponibilidade de Cd em solução, o que evidencia que a ação amenizante do P se deve às interações na planta, possivelmente reduzindo a translocação do Cd.In the present study the effects of phosphorus nutrition and arbuscular mycorrhiza (AM were evaluated on Cd toxicity to Trema micrantha (L. Blum.. In a first experiment, trema seedlings were raised in a P-enriched substrate (0, 100, 200 and 400 mg dm-3 and with an AM treatment (inoculation with Glomus etunicatum. After sixty days of growth, plants were transferred to Clark nutrient solution either without Cd added or amended with this metal at

  9. Global environmental change and the biology of arbuscular mycorrhizas: gaps and challenges

    DEFF Research Database (Denmark)

    Fitter, A.H.; Heinemeyer, A.; Husband, R.

    2004-01-01

    Our ability to make predictions about the impact of global environmental change on arbuscular mycorrhizal (AM) fungi and on their role in regulating biotic response to such change is seriously hampered by our lack of knowledge of the basic biology of these ubiquitous organisms. Current informatio...

  10. Competitive interactions are mediated in a sex-specific manner by arbuscular mycorrhiza in Antennaria dioica

    OpenAIRE

    Varga, Sandra; Vega-Frutis, Rocío; Kytöviita, Minna-Maarit

    2017-01-01

    Plants usually interact with other plants, and the outcome of such interaction ranges from facilitation to competition depending on the identity of the plants, including their sexual expression. Arbuscular mycorrhizal (AM) fungi have been shown to modify competitive interactions in plants. However, few studies have evaluated how AM fungi influence plant intraspecific and interspecific interactions in dioecious species. The competitive abilities of female and male plants of Antennaria dioic...

  11. Enhanced phytoremediation of soils contaminated with PAHs by arbuscular mycorrhiza and rhizobium.

    Science.gov (United States)

    Ren, Cheng-Gang; Kong, Cun-Cui; Bian, Bian; Liu, Wei; Li, Yan; Luo, Yong-Ming; Xie, Zhi-Hong

    2017-09-02

    Greenhouse experiment was conducted to evaluate the potential effectiveness of a legume (Sesbania cannabina), arbuscular mycorrhizal fungi (AMF) (Glomus mosseae), and rhizobia (Ensifer sp.) symbiosis for remediation of Polycyclic aromatic hydrocarbons (PAHs) in spiked soil. AMF and rhizobia had a beneficial impact on each other in the triple symbiosis. AMF and/or rhizobia significantly increased plant biomass and PAHs accumulation in plants. The highest PAHs dissipation was observed in plant + AMF + rhizobia treated soil, in which >97 and 85-87% of phenanthrene and pyrene, respectively, had been degraded, whereas 81-85 and 72-75% had been degraded in plant-treated soil. During the experiment, a relatively large amount of water-soluble phenolic compounds was detected in soils of AMF and/or rhizobia treatment. It matches well with the high microbial activity and soil enzymes activity. These results suggest that the mutual interactions in the triple symbiosis enhanced PAHs degradation via stimulating both microbial development and soil enzyme activity. The mutual interactions between rhizobia and AMF help to improve phytoremediation efficiency of PAHs by S. cannabina.

  12. Relative quantitative RT-PCR to study the expression of plant nutrient transporters in arbuscular mycorrhizas

    DEFF Research Database (Denmark)

    Burleigh, S.H.

    2001-01-01

    had high reproducibility and reflected trends in gene expression as observed by Northern blotting. Using this technique, it was demonstrated that both the high-affinity phosphate transporter MtPt2 and a putative nitrate transporter from Medicago truncatula were down-regulated in roots when colonized...

  13. Application of Mycorrhiza and Soil from a Permaculture System Improved Phosphorus Acquisition in Naranjilla.

    Science.gov (United States)

    Symanczik, Sarah; Gisler, Michelle; Thonar, Cécile; Schlaeppi, Klaus; Van der Heijden, Marcel; Kahmen, Ansgar; Boller, Thomas; Mäder, Paul

    2017-01-01

    Naranjilla ( Solanum quitoense ) is a perennial shrub plant mainly cultivated in Ecuador, Colombia, and Central America where it represents an important cash crop. Current cultivation practices not only cause deforestation and large-scale soil degradation but also make plants highly susceptible to pests and diseases. The use of arbuscular mycorrhizal fungi (AMF) can offer a possibility to overcome these problems. AMF can act beneficially in various ways, for example by improving plant nutrition and growth, water relations, soil structure and stability and protection against biotic and abiotic stresses. In this study, the impact of AMF inoculation on growth and nutrition parameters of naranjilla has been assessed. For inoculation three European reference AMF strains ( Rhizoglomus irregulare , Claroideoglomus claroideum , and Cetraspora helvetica ) and soils originating from three differently managed naranjilla plantations in Ecuador (conventional, organic, and permaculture) have been used. This allowed for a comparison of the performance of exotic AMF strains (reference strains) versus native consortia contained in the three soils used as inocula. To study fungal communities present in the three soils, trap cultures have been established using naranjilla as host plant. The community structures of AMF and other fungi inhabiting the roots of trap cultured naranjilla were assessed using next generation sequencing (NGS) methods. The growth response experiment has shown that two of the three reference AMF strains, a mixture of the three and soil from a permaculture site led to significantly better acquisition of phosphorus (up to 104%) compared to uninoculated controls. These results suggest that the use of AMF strains and local soils as inoculants represent a valid approach to improve nutrient uptake efficiency of naranjilla and consequently to reduce inputs of mineral fertilizers in the cultivation process. Improved phosphorus acquisition after inoculation with permaculture soil might have been caused by a higher abundance of AMF and the presence of Piriformospora indica as revealed by NGS. A higher frequency of AMF and enhanced root colonization rates in the trap cultures supplemented with permaculture soil highlight the importance of diverse agricultural systems for soil quality and crop production.

  14. The invasive plant, Brassica nigra, degrades local mycorrhizas across a wide geographical landscape.

    Science.gov (United States)

    Pakpour, Sepideh; Klironomos, John

    2015-09-01

    Disruption of mycorrhizal fungi that form symbioses with local native plants is a strategy used by some invasive exotic plants for competing within their resident communities. Example invasive plants include Alliaria petiolata (garlic mustard) and Brassica nigra (black mustard), both non-mycorrhizal plants in the Family Brassicaceae. Although there is clear evidence for mycorrhizal degradation, it is not known if such an effect is widespread across the naturalized range. In this study, we tested the ability of black mustard to degrade the local mycorrhizal symbiosis and supress the growth of native flora from across a variety of locations where black mustard has invaded. We found that the effects on mycorrhizal fungi and on the growth of native plants were consistently negative at the various sites. The present results indicate that degradation of the mycorrhizal symbiosis by black mustard is of general significance, and may be highly problematic considering the large range that it has occupied in open fields across North America.

  15. INFLUENCE OF MYCORRHIZAS, ORGANIC SUBSTRATES AND CONTAINER VOLUMES ON THE GROWTH OF Heliocarpus popayanensis Kunth

    Directory of Open Access Journals (Sweden)

    Waldemar Zangaro

    2015-09-01

    Full Text Available This work assessed, under nursery conditions, the effect of arbuscular mycorrhizal fungi (AMF inoculation on the initial growth of the woody species Heliocarpus popayanensis Kunth in containers of different sizes (nursery tubes of 50 or 250 cm3 containing composted cattle manure or organic Pinus spp bark compost diluted (0 to 100%, each 9% with low fertility soil. Plants in cattle manure grew more than plants grown in pine bark manure independent of tube size. AMF were more efficient in improving plant growth in 250 cm3 tubes than in 50 cm3 tubes independent of the substrates. Mycorrhizal plants grown in 50 cm3 tubes showed less growth than non-mycorrhizal ones irrespective of the substrates. Nevertheless, this growth depression decreased with an increase of substrates dilution with low fertility soil. In the higher dilutions, growth depression did not occur and there was a positive response to AMF inoculation. In addition, only mycorrhizal plantlets showed some growth in low fertility soil as the sole substrate. These results indicated that AMF affect plantlet growth positively or negatively depending on the combination of substrates, fertility level, and container size.

  16. Dose-response relationships between four pesticides and phosphorus uptake by hyphae of arbuscular mycorrhizas

    DEFF Research Database (Denmark)

    Schweiger, P.F.; Jakobsen, I.

    1998-01-01

    was separated from the main root compartment by nylon mesh. After 5 weeks of plant growth external hyphae of the AM fungi had spread throughout the hyphal compartment. At this time aqueous solutions of both P-32 and pesticide were added to the hyphal compartment. Resulting soil pesticide concentrations covered...

  17. Arbuscular mycorrhiza and plant succesion on zinc smelter spoil heap in Katowice-Wełnowiec

    OpenAIRE

    Ewa Gucwa-Przepióra; Katarzyna Turnau

    2014-01-01

    Mycorrhizal status of plants colonising the zinc wastes in Katowice was surveyed. In total 69 vascular plant species (25 families) appearing on the investigated area have been noted. More than 60% of them were mycorrhizal. Non-mycorrhizal species, such as Cardaminopsis arenosa and Silene vulgaris dominated the early successional part of the zinc heap. Tussilago farfara was the only AM plant there, however, no arbuscules were developed at this stage. The number of AM species was increased on t...

  18. Arbuscular mycorrhiza and plant succesion on zinc smelter spoil heap in Katowice-Wełnowiec

    Directory of Open Access Journals (Sweden)

    Ewa Gucwa-Przepióra

    2014-01-01

    Full Text Available Mycorrhizal status of plants colonising the zinc wastes in Katowice was surveyed. In total 69 vascular plant species (25 families appearing on the investigated area have been noted. More than 60% of them were mycorrhizal. Non-mycorrhizal species, such as Cardaminopsis arenosa and Silene vulgaris dominated the early successional part of the zinc heap. Tussilago farfara was the only AM plant there, however, no arbuscules were developed at this stage. The number of AM species was increased on the 20 years old part of the zinc wastes and on the older 30-50 years old areas. AM plants constituted about 60% of the total number of species there. The frequency of particular AM species was the highest on the oldest part of the investigated area. The usefulness of the results for restoration practices was discussed.

  19. Application of Mycorrhiza and Soil from a Permaculture System Improved Phosphorus Acquisition in Naranjilla

    Science.gov (United States)

    Symanczik, Sarah; Gisler, Michelle; Thonar, Cécile; Schlaeppi, Klaus; Van der Heijden, Marcel; Kahmen, Ansgar; Boller, Thomas; Mäder, Paul

    2017-01-01

    Naranjilla (Solanum quitoense) is a perennial shrub plant mainly cultivated in Ecuador, Colombia, and Central America where it represents an important cash crop. Current cultivation practices not only cause deforestation and large-scale soil degradation but also make plants highly susceptible to pests and diseases. The use of arbuscular mycorrhizal fungi (AMF) can offer a possibility to overcome these problems. AMF can act beneficially in various ways, for example by improving plant nutrition and growth, water relations, soil structure and stability and protection against biotic and abiotic stresses. In this study, the impact of AMF inoculation on growth and nutrition parameters of naranjilla has been assessed. For inoculation three European reference AMF strains (Rhizoglomus irregulare, Claroideoglomus claroideum, and Cetraspora helvetica) and soils originating from three differently managed naranjilla plantations in Ecuador (conventional, organic, and permaculture) have been used. This allowed for a comparison of the performance of exotic AMF strains (reference strains) versus native consortia contained in the three soils used as inocula. To study fungal communities present in the three soils, trap cultures have been established using naranjilla as host plant. The community structures of AMF and other fungi inhabiting the roots of trap cultured naranjilla were assessed using next generation sequencing (NGS) methods. The growth response experiment has shown that two of the three reference AMF strains, a mixture of the three and soil from a permaculture site led to significantly better acquisition of phosphorus (up to 104%) compared to uninoculated controls. These results suggest that the use of AMF strains and local soils as inoculants represent a valid approach to improve nutrient uptake efficiency of naranjilla and consequently to reduce inputs of mineral fertilizers in the cultivation process. Improved phosphorus acquisition after inoculation with permaculture soil might have been caused by a higher abundance of AMF and the presence of Piriformospora indica as revealed by NGS. A higher frequency of AMF and enhanced root colonization rates in the trap cultures supplemented with permaculture soil highlight the importance of diverse agricultural systems for soil quality and crop production. PMID:28769964

  20. Impact of roots, mycorrhizas and earthworms on soil physical properties as assessed by shrinkage analysis

    Science.gov (United States)

    Milleret, R.; Le Bayon, R.-C.; Lamy, F.; Gobat, J.-M.; Boivin, P.

    2009-07-01

    SummarySoil biota such as earthworms, arbuscular mycorrhizal fungi (AMF) and plant roots are known to play a major role in engineering the belowground part of the terrestrial ecosystems, thus strongly influencing the water budget and quality on earth. However, the effect of soil organisms and their interactions on the numerous soil physical properties to be considered are still poorly understood. Shrinkage analysis allows quantifying a large spectrum of soil properties in a single experiment, with small standard errors. The objectives of the present study were, therefore, to assess the ability of the method to quantify changes in soil properties as induced by single or combined effects of leek roots ( Allium porrum), AMF ( Glomus intraradices) and earthworms ( Allolobophora chlorotica). The study was performed on homogenised soil microcosms and the experiments lasted 35 weeks. The volume of the root network and the external fungal hyphae was measured at the end, and undisturbed soil cores were collected. Shrinkage analysis allowed calculating the changes in soil hydro-structural stability, soil plasma and structural pore volumes, soil bulk density and plant available water, and structural pore size distributions. Data analysis revealed different impacts of the experimented soil biota on the soil physical properties. At any water content, the presence of A. chlorotica resulted in a decrease of the specific bulk volume and the hydro-structural stability around 25%, and in a significant increase in the bulk soil density. These changes went with a decrease of the structural pore volumes at any pore size, a disappearing of the thinnest structural pores, a decrease in plant available water, and a hardening of the plasma. On the contrary, leek roots decreased the bulk soil density up to 1.23 g cm -3 despite an initial bulk density of 1.15 g cm -3. This increase in volume was accompanied with a enhanced hydro-structural stability, a larger structural pore volume at any pore size, smaller structural pore radii and an increase in plant available water. Interestingly, a synergistic effect of leek roots and AMF in the absence of the earthworms was highlighted, and this synergistic effect was not observed in presence of earthworms. The structural pore volume generated by root and AMF growth was several orders of magnitude larger than the volume of the organisms. Root exudates as well as other AMF secretion have served as carbon source for bacteria that in turn would enhance soil aggregation and porosity, thus supporting the idea of a self-organization of the soil-plant-microbe complex previously described.

  1. Influence of copper and formalin on the mycorrhiza of pine (Pinus kesiya Royle ex Gordon

    Directory of Open Access Journals (Sweden)

    G. D. Sharma

    2014-08-01

    Full Text Available Various concentrations of copper sulphate and formalin were tested for their effect on the efficiency of mycorrhizal functioning in pine seedlings. Low and higher doses of copper applied to the container grown seedling exhibited a less stimulatory effect than nedium doses. When applied in higher concentrations, the formalin caused mortality in young pine seedlings. The seedling yield and phosphate uptake was found maximum in 100 ppm applied concentration of copper. while słów growth and lower phosphate concentration was observed in the seedlings not given any copper treatment. Formalin at 50 ppm concentration slightly improved the seedling growth and phosphate uptake in mycorrhizal seedling as compared with untreated ones. Variation in the development and spread of ectomycorrhiza on the surface of roots of pine seedlings was also recorded in responses to copper and formalin treatments.

  2. Ectomycorrhizin Synthesis and Polypeptide Changes during the Early Stage of Eucalypt Mycorrhiza Development 1

    Science.gov (United States)

    Hilbert, Jean-Louis; Costa, Guy; Martin, Francis

    1991-01-01

    In functioning eucalypt ectomycorrhizas, biochemical alterations are accompanied by a differential accumulation of polypeptides including the synthesis of symbiosis-related proteins (JL Hilbert, Martin FM [1988] New Phytol 110: 339-346). In the present study, protein biosynthesis in the early stages of ectomycorrhiza formation on Eucalyptus globulus subsp. bicostata Kirkp. was examined using compatible and incompatible isolates of the basidiomycete Pisolithus tinctorius (Coker & Couch). Changes in polypeptide composition were observed within hours following contact of the compatible mycelium with the roots, well before the differentiation of typical symbiotic tissues. At this stage, at least seven symbiosis-related proteins (ectomycorrhizins) accumulated in root tissues. In vivo incorporation of [35S]methionine by ectomycorrhizas followed by electrophoresis of the labeled proteins revealed that most of these differences in polypeptide concentrations, including the ectomycorrhizin accumulation, are the result of differential protein biosynthesis rather than posttranslational modifications of the polypeptides. The initial development of eucalypt ectomycorrhizas, therefore, coincides with the synthesis of symbiosis-related proteins and the data presented here provide essential evidence to ascribe a functional developmental role to these proteins. ImagesFigure 2Figure 3Figure 4Figure 5 PMID:16668539

  3. Arbuscular mycorrhiza of plants from the Mountain Botanical Garden in Zakopane

    Directory of Open Access Journals (Sweden)

    Szymon Zubek

    2014-08-01

    Full Text Available The mycorrhizal status of 77 plant species collected from the Mountain Botanical Garden of the Polish Academy of Sciences in Zakopane (southern Poland was surveyed. These plants include rare, endemic and threatened species in the Tatra Mts. (the Western Carpathians and are maintained in the botanical garden in order to develop effective methods of protection and cultivation. Plants belonging to Brassicaceae, Caryophyllaceae, Dryopteridaceae, Juncaceae, Polygonaceae, Rubiaceae and Woodsiaceae families were nonmycorrhizal. 41 species formed AM symbiosis. Spores of nine AMF spccies (Glomeromycota, including Archaeospora trappei, Glomus aggregatum, G. claroideum, G. constrictum, G. deserticola, G. geosponrum, G. microcarpum, G. mosseae and G.rubiforme were isolated for the first time from this region of Poland. In addition, the occurrence of the fine endophyte, G. tenue was detected in roots of 18 species from the study area, although formation of arbuscules by this fungus was observed rarely. AM fungi were sporadically accompanied by dark septate endophytes (DSE. 70% of nonmycorrhizal plant sepcies were devoid of DSE.

  4. Can arbuscular mycorrhiza and fertilizer management reduce phosphorus runoff from paddy fields?

    Science.gov (United States)

    Zhang, Shujuan; Wang, Li; Ma, Fang; Zhang, Xue; Li, Zhe; Li, Shiyang; Jiang, Xiaofeng

    2015-07-01

    Our study sought to assess how much phosphorus (P) runoff from paddy fields could be cut down by fertilizer management and inoculation with arbuscular mycorrhizal fungi. A field experiment was conducted in Lalin River basin, in the northeast China: six nitrogen-phosphorus-potassium fertilizer levels were provided (0, 20%, 40%, 60%, 80%, and 100% of the recommended fertilizer supply), with or without inoculation with Glomus mosseae. The volume and concentrations of particle P (PP) and dissolved P (DP) were measured for each runoff during the rice growing season. It was found that the seasonal P runoff, including DP and PP, under the local fertilization was 3.7 kg/ha, with PP, rather than DP, being the main form of P in runoff water. Additionally, the seasonal P runoff dropped only by 8.9% when fertilization decreased by 20%; rice yields decreased with declining fertilization. We also found that inoculation increased rice yields and decreased P runoff at each fertilizer level and these effects were lower under higher fertilization. Conclusively, while rice yields were guaranteed arbuscular mycorrhizal inoculation and fertilizer management would play a key role in reducing P runoff from paddy fields. Copyright © 2015. Published by Elsevier B.V.

  5. Arbuscular mycorrhiza of endemic and endangered plants from the Tatra Mts

    Directory of Open Access Journals (Sweden)

    Szymon Zubek

    2011-01-01

    Full Text Available The mycorrhizal status of 24 plant species considered as endemic, endangered in Poland and included in the IUCN Red List of Threatened Plants is reported. Selected plants and rhizosphere soil samples were collected in the Tatra Mts (Western Carpathians. Individuals of seriously threatened taxa were obtained from seeds and inoculated with available AM fungal strains under laboratory conditions. AM colonisation was found in 16 plants; 9 species were of the Arum-type, 4 - Paris and 3 taxa revealed intermediate morphology. The mycelium of the fine endophyte (Glomus tenue and dark septate fungi (DSE were observed in the material collected in the field. 20 AMF species (Glomeromycota found in the rhizosphere of the investigated plants were reported for the first time from the Tatra Mts. The results provide information that might be useful for conservation and restoration programmes of these species. Application of AMF in active plant protection projects is discussed.

  6. Identification of arbuscular mycorrhiza-inducible Nitrate Transporter 1/Peptide Transporter Family (NPF) genes in rice.

    Science.gov (United States)

    Drechsler, Navina; Courty, Pierre-Emmanuel; Brulé, Daphnée; Kunze, Reinhard

    2017-10-09

    Arbuscular mycorrhizal fungi (AMF) colonize up to 90% of all land plants and facilitate the acquisition of mineral nutrients by their hosts. Inorganic orthophosphate (Pi) and nitrogen (N) are the major nutrients transferred from the fungi to plants. While plant Pi transporters involved in nutrient transfer at the plant-fungal interface have been well studied, the plant N transporters participating in this process are largely unknown except for some ammonium transporters (AMT) specifically assigned to arbuscule-colonized cortical cells. In plants, many nitrate transporter 1/peptide transporter family (NPF) members are involved in the translocation of nitrogenous compounds including nitrate, amino acids, peptides and plant hormones. Whether NPF members respond to AMF colonization, however, is not yet known. Here, we investigated the transcriptional regulation of 82 rice (Oryza sativa) NPF genes in response to colonization by the AMF Rhizophagus irregularis in roots of plants grown under five different nutrition regimes. Expression of the four OsNPF genes NPF2.2/PTR2, NPF1.3, NPF6.4 and NPF4.12 was strongly induced in mycorrhizal roots and depended on the composition of the fertilizer solution, nominating them as interesting candidates for nutrient signaling and exchange processes at the plant-fungal interface.

  7. The thalloid liverwort Plagiochasma rupestre supports arbuscular mycorrhiza-like symbiosis in vitro.

    Science.gov (United States)

    Silvani, Vanesa Analía; Rothen, Carolina Paola; Rodríguez, María Alejandra; Godeas, Alicia; Fracchia, Sebastián

    2012-12-01

    In the present study, we obtained in vitro dual cultures between the liverwort Plagiochasma rupestre and two arbuscular mycorrhizal (AM) fungi: Glomus intraradices and Glomus clarum. Four agarized culture media were tested for optimal growth of P. rupestre. Also, a description of the symbiotic association is provided. Plagiochasma rupestre gametophytes profusely grew axenically in MM with sucrose, and thalli were successfully subcultured under these growth conditions. Arbuscular mycorrhizal fungal hyphae colonized P. rupestre thalli through rhizoids or by forming appresoria in the ventral thallus cells. Arbuscules, mycelia and structures resembling intrathallic spores or vesicles were developed in the internal parenchymatic cells. The pattern of AM colonization in P. rupestre was very similar to the Paris-type. After 100 days of dual culture, the external mycelia of both AM fungal strains formed thousands of small viable spores, suggesting that P. rupestre in vitro culture could be a valuable tool for studying the biology of both symbiotic partners and conserving AM fungi in in vitro germplasm collections.

  8. Arsenate induces the expression of fungal genes involved in As transport in arbuscular mycorrhiza.

    Science.gov (United States)

    González-Chávez, Ma del Carmen A; Ortega-Larrocea, María del Pilar; Carrillo-González, Rogelio; López-Meyer, Melina; Xoconostle-Cázares, Beatriz; Gomez, Susana K; Harrison, Maria J; Figueroa-López, Alejandro Miguel; Maldonado-Mendoza, Ignacio E

    2011-12-01

    We utilized the two-compartment system to study the effect of arsenic (As) on the expression of the Glomus intraradices high-affinity phosphate transporter GiPT, and the GiArsA gene, a novel protein with a possible putative role as part of an arsenite efflux pump and similar to ArsA ATPase. Our results show that induction of GiPT expression correlates with As(V) uptake in the extra-radical mycelium of G. intraradices. We showed a time-concerted induction of transcript levels first of GiPT, followed by GiArsA, as well as the location of gene expression using laser microdissection of these two genes not only in the extra-radical mycelium but also in arbuscules. This work represents the first report showing the dissection of the molecular players involved in arbuscular mycorrhizal fungus (AMF)-mediated As tolerance in plants, and suggests that tolerance mediated by AMF may be caused by an As exclusion mechanism, where fungal structures such as the extra-radical mycelium and arbuscules may be playing an important role. Our results extend knowledge of the mechanisms underlying As efflux in arbuscular mycorrhizal fungi and mechanisms related to As tolerance. Copyright © 2011 British Mycological Society. All rights reserved.

  9. Effect of arbuscular mycorrhiza fungi on growth and development of onion and wild relatives

    NARCIS (Netherlands)

    Scholten, O.M.; Galvan-Vivero, G.; Burger-Meijer, K.; Baar, J.; Kik, C.

    2006-01-01

    Arbuscular mycorrhizal fungi play an important role in the uptake of nutrients and water from soil. Onions, Allium cepa L., are plants with a shallow root system. As a result, onion plants need a lot of fertiziler for their growth. Furthermore, onion plants are sensitive to drought. The aim of the

  10. Occurence of arbuscular mycorrhiza and extomycorrhiza on Leptospermum scoparium from the Rakaia catchment, Canterbury.

    NARCIS (Netherlands)

    Weijtmans, K.; Davis, M.; Clinton, P.; Kuyper, T.W.; Greenfield, L.

    2007-01-01

    Leptospermum is one of only three New Zealand genera that are colonised by ectomycorrhizal (EM) fungi, and L. scoparium is one of the very few New Zealand species that can be colonised by both arbuscular mycorrhizal (AM) and EM fungi. This study examined AM and EM colonisation on L. scoparium

  11. Roles of arbuscular mycorrhizas in plant nutrition and growth: new paradigms from cellular to ecosystem scales.

    Science.gov (United States)

    Smith, Sally E; Smith, F Andrew

    2011-01-01

    Root systems of most land plants form arbuscular mycorrhizal (AM) symbioses in the field, and these contribute to nutrient uptake. AM roots have two pathways for nutrient absorption, directly through the root epidermis and root hairs and via AM fungal hyphae into root cortical cells, where arbuscules or hyphal coils provide symbiotic interfaces. New physiological and molecular evidence shows that for phosphorus the mycorrhizal pathway (MP) is operational regardless of plant growth responses (positive or negative). Amounts delivered cannot be determined from plant nutrient contents because when responses are negative the contribution of the direct pathway (DP) is reduced. Nitrogen (N) is also delivered to roots via an MP, but the contribution to total N requirement and the costs to the plant are not clear. The functional interplay between activities of the DP and MP has important implications for consideration of AM symbioses in ecological, agronomic, and evolutionary contexts.

  12. Arbuscular mycorrhiza: the challenge to understand the genetics of the fungal partner.

    Science.gov (United States)

    Sanders, Ian R; Croll, Daniel

    2010-01-01

    Arbuscular mycorrhizal symbioses occur between fungi and the majority of plant species. They are important for plant nutrition, plant growth, protection from pathogens, plant diversity, nutrient cycling, and ecosystem processes. A key goal in research is to understand the molecular basis of the establishment, regulation, and functioning of the symbiosis. However, lack of knowledge on the genetics of the fungal side of this association has hindered progress. Here, we show how several key, recently discovered processes concerning the genetics of arbuscular mycorrhizal fungi could be essential for ultimately understanding the molecular genetics of this important symbiosis with plants.

  13. Lights Off for Arbuscular Mycorrhiza: On Its Symbiotic Functioning under Light Deprivation.

    Science.gov (United States)

    Konvalinková, Tereza; Jansa, Jan

    2016-01-01

    Plants are often exposed to shade over different time scales and this may substantially affect not only their own growth, but also development and functioning of the energetically dependent organisms. Among those, the root symbionts such as arbuscular mycorrhizal (AM) fungi and rhizobia represent particularly important cases-on the one hand, they consume a significant share of plant carbon (C) budget and, on the other, they generate a number of important nutritional feedbacks on their plant hosts, often resulting in a net positive effect on their host growth and/or fitness. Here we discuss our previous results comparing mycorrhizal performance under different intensities and durations of shade (Konvalinková et al., 2015) in a broader context of previously published literature. Additionally, we review publicly available knowledge on the root colonization and mycorrhizal growth responses in AM plants under light deprivation. Experimental evidence shows that sudden and intensive decrease of light availability to a mycorrhizal plant triggers rapid deactivation of phosphorus transfer from the AM fungus to the plant already within a few days, implying active and rapid response of the AM fungus to the energetic status of its plant host. When AM plants are exposed to intensive shading on longer time scales (weeks to months), positive mycorrhizal growth responses (MGR) are often decreasing and may eventually become negative. This is most likely due to the high C cost of the symbiosis relative to the C availability, and failure of plants to fully compensate for the fungal C demand under low light. Root colonization by AM fungi often declines under low light intensities, although the active role of plants in regulating the extent of root colonization has not yet been unequivocally demonstrated. Quantitative information on the rates and dynamics of C transfer from the plant to the fungus is mostly missing, as is the knowledge on the involved molecular mechanisms. Therefore, these subjects deserve particular attention in the future.

  14. The role of arbuscular mycorrhizas in decreasing aluminium phytotoxicity in acidic soils: a review.

    Science.gov (United States)

    Seguel, Alex; Cumming, Jonathan R; Klugh-Stewart, Katrina; Cornejo, Pablo; Borie, Fernando

    2013-04-01

    Soil acidity is an impediment to agricultural production on a significant portion of arable land worldwide. Low productivity of these soils is mainly due to nutrient limitation and the presence of high levels of aluminium (Al), which causes deleterious effects on plant physiology and growth. In response to acidic soil stress, plants have evolved various mechanisms to tolerate high concentrations of Al in the soil solution. These strategies for Al detoxification include mechanisms that reduce the activity of Al3+ and its toxicity, either externally through exudation of Al-chelating compounds such as organic acids into the rhizosphere or internally through the accumulation of Al-organic acid complexes sequestered within plant cells. Additionally, root colonization by symbiotic arbuscular mycorrhizal (AM) fungi increases plant resistance to acidity and phytotoxic levels of Al in the soil environment. In this review, the role of the AM symbiosis in increasing the Al resistance of plants in natural and agricultural ecosystems under phytotoxic conditions of Al is discussed. Mechanisms of Al resistance induced by AM fungi in host plants and variation in resistance among AM fungi that contribute to detoxifying Al in the rhizosphere environment are considered with respect to altering Al bioavailability.

  15. Functional biology of plant phosphate uptake at root and mycorrhiza interfaces.

    Science.gov (United States)

    Bucher, Marcel

    2007-01-01

    Phosphorus (P) is an essential plant nutrient and one of the most limiting in natural habitats as well as in agricultural production world-wide. The control of P acquisition efficiency and its subsequent uptake and translocation in vascular plants is complex. The physiological role of key cellular structures in plant P uptake and underlying molecular mechanisms are discussed in this review, with emphasis on phosphate transport across the cellular membrane at the root and arbuscular-mycorrhizal (AM) interfaces. The tools of molecular genetics have facilitated novel approaches and provided one of the major driving forces in the investigation of the basic transport mechanisms underlying plant P nutrition. Genetic engineering holds the potential to modify the system in a targeted way at the root-soil or AM symbiotic interface. Such approaches should assist in the breeding of crop plants that exhibit improved P acquisition efficiency and thus require lower inputs of P fertilizer for optimal growth. Whether engineering of P transport systems can contribute to enhanced P uptake will be discussed.

  16. Arbuscular mycorrhiza alter the concentration of essential oils in oregano (Origanum sp., Lamiaceae).

    Science.gov (United States)

    Khaosaad, T; Vierheilig, H; Nell, M; Zitterl-Eglseer, K; Novak, J

    2006-09-01

    The effect of root colonization by Glomus mosseae on the qualitative and quantitative pattern of essential oils (EO) was determined in three oregano genotypes (Origanum sp.). To exclude a simple P-mediated effect through mycorrhization the effect of P application to plants on the EO accumulation was also tested. In two genotypes the leaf biomass was increased through mycorrhization. Root colonization by the arbuscular mycorrhizal fungus (AMF) did not have any significant effect on the EO composition in oregano; however, in two genotypes the EO concentration significantly increased. As EO levels in P-treated plants were not enhanced, we conclude that the EO increase observed in mycorrhizal oregano plants is not due to an improved P status in mycorrhizal plants, but depends directly on the AMF-oregano plant association.

  17. Effect of mycorrhiza symbiosis on the Nacl salinity in Sorghum bicolor

    African Journals Online (AJOL)

    In order to determine mycorrhizal symbiosis on the Nacl salinity tolerance in Sorghum bicolor (aspydfyd cultivar), an experiment with two factors was done in Damghan Islamic Azad University laboratory (Iran) in 2007. The first factor with two levels (mycorihizal and non-mycorihizal) and second factor with six levels Nacl ...

  18. Influences of agricultural management practices on Arbuscular Mycorrhiza Fungal symbioses in Kenyan agro-ecosystems

    NARCIS (Netherlands)

    Muriithi-Muchane, M.N.

    2013-01-01

    Conservation agriculture (CA) and integrated soil fertility management (ISFM) practices are receiving increased attention as pathways to sustainable high-production agriculture in sub-Saharan Africa. However, little is known about the effects of these practices on arbuscular mycorrhizal fungi (AMF).

  19. Application of Mycorrhiza and Soil from a Permaculture System Improved Phosphorus Acquisition in Naranjilla

    Directory of Open Access Journals (Sweden)

    Sarah Symanczik

    2017-07-01

    Full Text Available Naranjilla (Solanum quitoense is a perennial shrub plant mainly cultivated in Ecuador, Colombia, and Central America where it represents an important cash crop. Current cultivation practices not only cause deforestation and large-scale soil degradation but also make plants highly susceptible to pests and diseases. The use of arbuscular mycorrhizal fungi (AMF can offer a possibility to overcome these problems. AMF can act beneficially in various ways, for example by improving plant nutrition and growth, water relations, soil structure and stability and protection against biotic and abiotic stresses. In this study, the impact of AMF inoculation on growth and nutrition parameters of naranjilla has been assessed. For inoculation three European reference AMF strains (Rhizoglomus irregulare, Claroideoglomus claroideum, and Cetraspora helvetica and soils originating from three differently managed naranjilla plantations in Ecuador (conventional, organic, and permaculture have been used. This allowed for a comparison of the performance of exotic AMF strains (reference strains versus native consortia contained in the three soils used as inocula. To study fungal communities present in the three soils, trap cultures have been established using naranjilla as host plant. The community structures of AMF and other fungi inhabiting the roots of trap cultured naranjilla were assessed using next generation sequencing (NGS methods. The growth response experiment has shown that two of the three reference AMF strains, a mixture of the three and soil from a permaculture site led to significantly better acquisition of phosphorus (up to 104% compared to uninoculated controls. These results suggest that the use of AMF strains and local soils as inoculants represent a valid approach to improve nutrient uptake efficiency of naranjilla and consequently to reduce inputs of mineral fertilizers in the cultivation process. Improved phosphorus acquisition after inoculation with permaculture soil might have been caused by a higher abundance of AMF and the presence of Piriformospora indica as revealed by NGS. A higher frequency of AMF and enhanced root colonization rates in the trap cultures supplemented with permaculture soil highlight the importance of diverse agricultural systems for soil quality and crop production.

  20. The role of the arbuscular mycorrhiza-associated rhizobacteria in the biocontrol of soilborne phyto pathogens

    Energy Technology Data Exchange (ETDEWEB)

    Lioussanne, L.

    2010-07-01

    The mutualistic symbiosis of most land plants with arbuscular mycorrhizal (AM) fungi has been shown to favor mineral and water nutrition and to increase resistance to abiotic and biotic stresses. This review reports the main mechanisms involved in the control of the disease symptoms and of the intraradical proliferation of soilborne phytopathogens by root colonization with AM fungi, with a special emphasis on the role of the rhizobacteria shown to be specifically associated with the AM extraradical network and the mycorrhizosphere (the soil zone with particular characteristics under the influence of the root/AM association). The mycorrhizosphere would constitute an environment conducive to microorganisms antagonistic to pathogen proliferation. Moreover, attempts to identify rhizobacteria from AM structures and/or the mycorrhizosphere often lead to the isolation of organisms showing strong properties of antagonism on various soilborne pathogens. The ability of AM fungi to control soilborne diseases would be strongly related to their capacity to specifically stimulate the establishment of rhizobacteria unfavorable to pathogen development within the mycorrhizosphere before root infection. Current knowledge concerning the mechanisms involved in AM/rhizobacteria interactions are also described in this review. (Author) 101 refs.