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Sample records for vesicular arbuscular mycorrhizae

  1. 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...

  2. 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 ...

  3. 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

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

    OpenAIRE

    Lin, XG.; Hao, WY.; Wu, TH.

    1993-01-01

    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 ...

  5. Dynamics of vesicular-arbuscular mycorrhizae during old field succession.

    Science.gov (United States)

    Johnson, Nancy Collins; Zak, Donald R; Tilman, David; Pfleger, F L

    1991-05-01

    The species composition of vesicular-arbuscular mycorrhizal (VAM) fungal communities changed during secondary succession of abandoned fields based on a field to forest chronosequence. Twenty-five VAM fungal species were identified. Seven species were clearly early successional and five species were clearly late successional. The total number of VAM fungal species did not increase with successional time, but diversity as measured by the Shannon-Wiener index tended to increase, primarily because the community became more even as a single species, Glomus aggregatum, became less dominant in the older sites. Diversity of the VAM fungal community was positively correlated with soil C and N. The density of VAM fungi, as measured by infectivity and total spore count, first increased with time since abandonment and then decreased in the late successional forest sites. Within 12 abandoned fields, VAM fungal density increased with increasing soil pH, H 2 O soluble soil C, and root biomass, but was inversely related to extractable soil P and percent cover of non-host plant species. The lower abundance of VAM fungi in the forest sites compared with the field sites agrees with the findings of other workers and corresponds with a shift in the dominant vegetation from herbaceous VAM hosts to woody ectomycorrhizal hosts.

  6. 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.

  7. Natural re-establishment of vesicular-arbuscular mycorrhizae following stripmine reclamation in Wyoming

    Energy Technology Data Exchange (ETDEWEB)

    Allen, E.B.; Allen, M.F. (University of Wyoming, Laramie, WY (USA))

    1980-01-01

    The % root infection of {ital Agropyron smithii} and {ital A. intermedium} by vesicular-arbuscular mycorrhizae was measured and spoil spores were counted in six reclaimed stripmine sites in Wyoming. On 2- and 3-yr old sites % infection and spore counts were c. 50% or less than native prairie levels. Spore counts of a 3-yr old disked prairie site were not different from the undisturbed prairie level, but infection was significantly lower. Spore counts of the reclimed sites were not highly correlated with % root infection. Five of seven annuals which colonized the reclaimed and disked sites were non-mycorrhizal. 43 refs., 3 tabs.

  8. 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...... and inoculation increased the uptake of bromide, Zn and Cu significantly. Mycorrhizal infection in inoculated plots was first observed 25 days after seedling emergence, and final infection levels were c. 50% in contrast to 12 % without inoculation. The introduced endophyte had spread 30 cm horizontally during...

  9. 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...

  10. Vesicular-arbuscular mycorrhizae of Easter lily in the northwestern United States.

    Science.gov (United States)

    Ames, R N; Linderman, R G

    1977-12-01

    The vesicular-arbuscular (VA) mycorrhizal fungi of commercially grown Easter lily (Lilium longiflorum Thunb.) were studied. Soil and root samples were collected monthly from March through September 1975 from five fields in the coastal area of southern Oregon and northern California. Soil seivings were inoculated onto clover, onion, and lily to cause infections resulting in the production of many new mycorrhizal spores facilitating identification. Four VA mycorrhizal species were found: Acaulospora trappei, A. elegans, Glomus monosporus, and G. fasciculatus. All four VA species infected Easter lily, clover, and onion. Acaulospora trappei and G. fasciculatus were the most commonly isolated species from all five fields. Mycorrhizal infections in roots of field-grown lilies were sparse and presumably young in March and gradually increased in size and number until September when bulbs were harvested. Over 75% of each root system became infected with mycorrhizae in fields with all four fungal species, and those levels were reached by July. In fields with only two mycorrhizal species, usually 50% or less of each root system was infected, even by the end of the growing season.

  11. 32P uptake and translocation in chickpea (Cicer arietinum L.) inoculated with vesicular-arbuscular mycorrhiza

    International Nuclear Information System (INIS)

    Chaturvedi, C.; Singh, Renu

    1990-01-01

    32 P uptake in chickpea (Cicer arietinum L.) cultivars L-550 and C-235 as affected by vesicualr-arbuscular mycorrhiza (G. caledonicum) and Rhizobium was investigated in P deficient soils. Test plants coinoculated with the above two symbionts exhibited higher 32 P uptake than inoculated with either symbiont alone. Uninoculated plants showed minimum level of 32 P uptake. (author). 1 tab., 7 refs

  12. Effects of vesicular-arbuscular mycorrhizae on survival and growth of perennial grasses in lignite overburden in Texas

    Energy Technology Data Exchange (ETDEWEB)

    Call, C.A.; Davies, F.T.

    1988-12-01

    Seedlings of sideoats grama (Bouteloua curtipendula), Indiangrass (Sorghastrum nutans), and kleingrass (Panicum coloratum) were inoculated with vesicular-arbuscular mycorrhizal (VAM) fungi (Glomus fasciculatum and Gigaspora margarita) in a containerized system and transplanted into lignite overburden in the Post Oak Savannah region of Texas, U.S.A. After three growing seasons without cultural inputs, plants inoculated with VAM fungi had greater survival percentages, basal diameters, and above-ground biomass than noninoculated plants. Inoculated plants had higher levels of nitrogen and phosphorus in above-ground biomass than noninoculated plants. Root colonization percentages of inoculated plants remained fairly stable while noninoculated plants showed low levels of colonization over the 3-year study period. Vesicular-arbuscular mycorrhizae enhanced the survival and growth of the 3 grass species by making effective use of limited resources in the lignite overburden. 31 refs., 3 tabs.

  13. The effect of vesicular-arbuscular mycorrhiza isolated from Syrian soil on alfalfa growth and nitrogen fixation in saline soil

    International Nuclear Information System (INIS)

    El Atrash, F

    2001-01-01

    The influence of vesicular - arbuscular Mycorrhiza fungi (VAM) on symbiotic fixation of N 2 n alfalfa plants has been observed. Beneficial effects of study the effect of VAM or phosphorous fertilization on alfalfa (Medicago sativa L,) yields, umber of nodules and N 2 fixation by N 15 isotope dilution at different salinity levels. This experiment was realized in green house conditions, using soil of 2.3 dsm -1 conductivity mixed with sand (5: 2V) for alfalfa plants growing at various levels of phosphorus, or infected by Mycorrhiza fungi. Different conductivities (13.18, 22.2, 28.8, 43.5 dsm -1 ) were applied on these treatment by increasing concentrations of Nacl, CaCl 2 and MgCl 2 and MgCl 2 by salinity soil irrigation. Ten days after planting, soil was enriched with 2 ppm of (NH 4 15 ) 2 SO 4 . Plant were grown under greenhouse condition for ten weeks. Our results confirmed that increased salinity reduced nitrogen - fixation and the number of nodules. The negative effect with increasing salinity was less in Mycorrhiza plants than in plants fertilized with various levels of phosphorus, and only the higher levels of salinity reduced significantly, the percentage of Mycorrhiza colonization, However, at all levels of salinity, VAM stimulated plant growth and nutrient uptake. (author)

  14. Vesicular-arbuscular-/ecto-mycorrhiza succession in seedlings of. Eucalyptus spp. Sucessão de micorrizas vesicular-arbuscular e ectomicorrizas em mudas de Eucalyptus spp.

    Directory of Open Access Journals (Sweden)

    Vera Lúcia dos Santos

    2001-06-01

    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.A ocorrência de micorrizas arbusculares (AM e ectomicorrizas (ECM no mesmo sistema radicular foi observada quando Eucalyptus urophylla S.T. Blake, E. citriodora Hook F., E. grandis W. Hill ex Maiden, E. cloeziana F. Muell e E. camaldulensis Dehnh foram inoculadas simultaneamente com Glomus etunicatum Becker & Gederman and Pisolithus tinctorius (Per. Cocker & Couch. A sucessão entre os dois fungos foi observada. De modo geral, o aumento da colonização ECM foi acompanhado de um decréscimo em AM. A inoculação simultânea resultou em percentagens de colonização diferenciadas das

  15. Occurrence of vesicular-arbuscular mycorrhizae in mixed overburden mine spoils of Texas

    Energy Technology Data Exchange (ETDEWEB)

    Mott, J.B.; Zuberer, D.A.

    1987-07-01

    Presently in east Texas, lignite surface mines are reclaimed and revegetated using mixed overburden materials which are equivalent to or better in physical-chemical properties than the poor topsoils removed during mining. Little information is available regarding the biological characteristics of levelled mixed overburden and the re-establishment of endomycorrhizal associations on revegetated mixed overburden sites. Therefore, the authors investigated the occurrence of infection of coastal bermudagrass (Cynodon dactylon), planted vegetatively on reclamation sites (1-10 years post-mining), with vesicular-arbuscular mycorrhizal (VAM) fungi. Numbers of spores were also monitored. For comparison, infection of coastal bermudagrass and spore numbers were determined for an unmined old field succession on soil typical of the region. VAM infection, measured as a percentage of root length infected or as a percentage of root segments exhibiting infection, returned to pre-mining levels by 3-7 years after disturbance. Intensity of infection was not altered by disturbance, age of reclaimed site, or season. Significantly greater numbers of spores (ca. 10-fold) were observed in the unmined soil and no differences were found between numbers of spores from variously aged mine spoil sites. 35 refs., 3 tabs.

  16. Interaction of Vesicular-Arbuscular Mycorrhizae and Cultivars of Alfalfa Susceptible and Resistant to Meloidogyne hapla.

    Science.gov (United States)

    Grandison, G S; Cooper, K M

    1986-04-01

    The interaction between vesicular-arbuscular mycorrhizal (VAM) fungi and the root-knot nematode (Meloidogyne hapla) was investigated using both nematode-susceptible (Grasslands Wairau) and nematode-resistant (Nevada Synthetic XX) cultivars of alfalfa (Medicago sativa) at four levels of applied phosphate. Mycorrhizal inoculation improved plant growth and reduced nematode numbers and adult development in roots in dually infected cultures of the susceptible cultivar. The tolerance of plants to nematode infection and development when preinfected with mycorrhizal fungi was no greater than when they were inoculated with nematodes and mycorrhizal fungi simultaneously. Growth of plants of the resistant cultivar was unaffected by nematode inoculation but was improved by mycorrhizal inoculation. Numbers of nematode juveniles were lower in the roots of the resistant than of the susceptible cultivar and were further reduced by mycorrhizal inoculation, although no adult nematodes developed in any resistant cultivar treatment. Inoculation of alfalfa with VAM fungi increased the tolerance and resistance of a cultivar susceptible to M. hapla and improved the resistance of a resistant cultivar.

  17. 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.

  18. 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.

  19. 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.

  20. 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 by...... in relation to final phosphorus uptake and dry-matter production, and it is proposed that a relatively low soil-phosphorus availability was counterbalanced, to some extent, by a well-developed VAM infection....

  1. 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, ...

  2. 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.

  3. Quantitative and qualitative effects of phosphorus on extracts and exudates of sudangrass roots in relation to vesicular-arbuscular mycorrhiza formation.

    Science.gov (United States)

    Schwab, S M; Menge, J A; Leonard, R T

    1983-11-01

    A comparison was made of water-soluble root exudates and extracts of Sorghum vulgare Pers. grown under two levels of P nutrition. An increase in P nutrition significantly decreased the concentration of carbohydrates, carboxylic acids, and amino acids in exudates, and decreased the concentration of carboxylic acids in extracts. Higher P did not affect the relative proportions of specific carboxylic acids and had little effect on proportions of specific amino acids in both extracts and exudates. Phosphorus amendment resulted in an increase in the relative proportion of arabinose and a decrease in the proportion of fructose in exudates, but did not have a large effect on the proportion of individual sugars in extracts. The proportions of specific carbohydrates, carboxylic acids, and amino acids varied between exudates and extracts. Therefore, the quantity and composition of root extracts may not be a reliable predictor of the availability of substrate for symbiotic vesicular-arbuscular mycorrhizal fungi. Comparisons of the rate of leakage of compounds from roots with the growth rate of vesicular-arbuscular mycorrhizal fungi suggest that the fungus must either be capable of using a variety of organic substrates for growth, or be capable of inducing a much higher rate of movement of specific organic compounds across root cell membranes than occurs through passive exudation as measured in this study.

  4. Accumulation of New Polypeptides in Ri T-DNA-Transformed Roots of Tomato (Lycopersicon esculentum) during the Development of Vesicular-Arbuscular Mycorrhizae.

    Science.gov (United States)

    Simoneau, P; Louisy-Louis, N; Plenchette, C; Strullu, D G

    1994-06-01

    Root-inducing transferred-DNA (Ri T-DNA)-transformed roots of tomato (Lycopersicon esculentum) were in vitro inoculated with surface-sterilized vesicular-arbuscular mycorrhizal leek root pieces. About 1 week after inoculation, the infection of the transformed root culture by the fungal endophyte was confirmed by photonic microscopy. Total proteins were extracted from the mycorrhizal roots and analyzed by two-dimensional polyacrylamide gel electrophoresis. Control gels were run with proteins extracted from noninoculated roots mixed with purified intraradical vesicles and extraradical hyphae. Comparison of the resulting patterns revealed the presence of two polypeptides with estimated apparent masses of 24 and 39 kDa that were detected only in infected roots. Polypeptides with similar migration parameters were not detected in roots challenged with spore extracts, suggesting that the accumulation of the polypeptides was directly linked to root colonization by the fungus rather than to induction by fungus-derived elicitors.

  5. Arbuscular mycorrhiza in soil quality assessment

    DEFF Research Database (Denmark)

    Kling, M.; Jakobsen, I.

    1998-01-01

    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......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...... 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....

  6. Regulation of arbuscular mycorrhizae development

    OpenAIRE

    Kiriachek, Soraya Gabriela; Azevedo, Lucas Carvalho Basilio de; Peres, Lázaro Eustáquio Pereira; Lambais, Marcio Rodrigues

    2009-01-01

    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...

  7. Arbuscular mycorrhizas are present on Spitsbergen.

    Science.gov (United States)

    Newsham, K K; Eidesen, P B; Davey, M L; Axelsen, J; Courtecuisse, E; Flintrop, C; Johansson, A G; Kiepert, M; Larsen, S E; Lorberau, K E; Maurset, M; McQuilkin, J; Misiak, M; Pop, A; Thompson, S; Read, D J

    2017-10-01

    A previous study of 76 plant species on Spitsbergen in the High Arctic concluded that structures resembling arbuscular mycorrhizas were absent from roots. Here, we report a survey examining the roots of 13 grass and forb species collected from 12 sites on the island for arbuscular mycorrhizal (AM) colonisation. Of the 102 individuals collected, we recorded AM endophytes in the roots of 41 plants of 11 species (Alopecurus ovatus, Deschampsia alpina, Festuca rubra ssp. richardsonii, putative viviparous hybrids of Poa arctica and Poa pratensis, Poa arctica ssp. arctica, Trisetum spicatum, Coptidium spitsbergense, Ranunculus nivalis, Ranunculus pygmaeus, Ranunculus sulphureus and Taraxacum arcticum) sampled from 10 sites. Both coarse AM endophyte, with hyphae of 5-10 μm width, vesicles and occasional arbuscules, and fine endophyte, consisting of hyphae of 1-3 μm width and sparse arbuscules, were recorded in roots. Coarse AM hyphae, vesicles, arbuscules and fine endophyte hyphae occupied 1.0-30.7, 0.8-18.3, 0.7-11.9 and 0.7-12.8% of the root lengths of colonised plants, respectively. Principal component analysis indicated no associations between the abundances of AM structures in roots and edaphic factors. We conclude that the AM symbiosis is present in grass and forb roots on Spitsbergen.

  8. Use of arbuscular mycorrhiza fungi for improved crop production in ...

    African Journals Online (AJOL)

    Arbuscular mycorrhiza fungi (AMF), endophytic fungi reputed for their ability to enhance P uptake can be used to alleviate P deficiencies and improve crop productivity. Although the technology has been used in developed countries, it has not been applied in crop production systems in Africa to any significant level. This is ...

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

    African Journals Online (AJOL)

    STORAGESEVER

    2008-10-06

    Oct 6, 2008 ... ... association between certain plants and microorganisms plays an important role in soil ..... an Agrostis capillaris population on a copper contaminated soil. Plant ... vesicular-arbuscular mycorrhizal fungi in Amazonian Peru.

  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. The distribution of vesicular-arbuscular mycorrhizal fungi in India.

    Science.gov (United States)

    Rani, R; Mukerji, K G

    1990-01-01

    Vesicular-arbuscular mycorrhizal fungi are widely distributed throughout the area studied including different altitudes ranging from sea level to 2500 ft above sea level. VAM fungi were recorded from 88% of the sites examined with Glomus fasciculatum and Glomus macrocarpum being the most commonly recorded. Mean species diversity was found to be maximum in the areas thickly vegetated and undisturbed.

  12. 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.

  13. Airstream fractionation of vesicular-arbuscular mycorrhizal fungi: concentration and enumeration of propagules.

    Science.gov (United States)

    Tommerup, I C

    1982-09-01

    Spores and fragments of vesicular-arbuscular mycorrhizal fungi in dry soils were concentrated up to 100-fold when the soils were partitioned by fluidization and elutriation with a series of upward airstreams at progressively increasing velocities. The propagules were transported with the finer soil particles according to their equivalent spherical diameters. The system was used to predict the transport of propagules by wind. Concentrated propagules were rapidly separated from the soil particles in each soil fraction by an aqueous flotation method. The technique is proposed as a quantitative method for estimating the numbers of spores and fragments of mycorrhizae. The scheme includes a viability test that was used to differentiate between potentially infective propagules and those that were either dormant or incapable of regrowth.

  14. 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...

  15. 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.

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

    International Nuclear Information System (INIS)

    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 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

  17. 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.

  18. 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......-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...

  19. 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 O 3 on arbuscular mycorrhiza (AM) formation and on AM role in promoting plant growth in regard to several moderating variables (O 3 levels, O 3 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 O 3 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 O 3 exposure but did not differ much with AM fungi taxa or plant type. AM symbiosis has also led to higher yields under O 3 stress, relative to the non-mycorrhizal plants, and the AM effects have been more pronounced as O 3 concentration increases. As with biomass, AM effects on yield have been affected by the duration of O 3 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 O 3 compared to ambient O 3 ; total mycorrhizal colonization rate (MCR), arbuscular MCR, vesicular MCR and hyphal coil MCR declined as O 3 levels rose. AM colonization rates were affected by duration of O 3 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 O 3 on plant growth and productivity, despite colonization rates being negatively affected by elevated O 3 . Copyright © 2017. Published by Elsevier Ltd.

  20. Arbuscular mycorrhiza differentially affects synthesis of essential oils in coriander and dill

    Czech Academy of Sciences Publication Activity Database

    Rydlová, Jana; Jelínková, M.; Dušek, K.; Dušková, E.; Vosátka, Miroslav; Püschel, David

    2016-01-01

    Roč. 26, č. 2 (2016), s. 123-131 ISSN 0940-6360 R&D Projects: GA MŠk 1M0571 Institutional support: RVO:67985939 Keywords : arbuscular mycorrhiza * aromatic plants * essential oils Subject RIV: EF - Botanics Impact factor: 3.047, year: 2016

  1. Arbuscular mycorrhiza stimulates biological nitrogen fixation in two Medicago spp. through omproved phosphorus acquisition

    Czech Academy of Sciences Publication Activity Database

    Püschel, David; Janoušková, Martina; Voříšková, Alena; Gryndlerová, H.; Vosátka, Miroslav; Jansa, J.

    2017-01-01

    Roč. 8, MAR 27 (2017), s. 1-12, č. článku no. 390. ISSN 1664-462X R&D Projects: GA ČR GA15-05466S Institutional support: RVO:67985939 Keywords : arbuscular mycorrhiza * biological nitrogen fixation * phosphorus uptake Subject RIV: EH - Ecology, Behaviour OBOR OECD: Ecology Impact factor: 4.298, year: 2016

  2. Gibberellin-Abscisic Acid Balances during Arbuscular Mycorrhiza Formation in Tomato

    Czech Academy of Sciences Publication Activity Database

    Martin-Rodriguez, J.A.; Huertas, R.; Ho-Plagaro, T.; Ocampo, J.A.; Turečková, Veronika; Tarkowská, Danuše; Ludwig-Mueller, J.; Garcia-Garrido, J.M.

    2016-01-01

    Roč. 7, AUG 23 (2016), s. 1273 ISSN 1664-462X R&D Projects: GA ČR GA14-34792S; GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : arbuscular mycorrhiza * plant hormones * gibberellins Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 4.298, year: 2016

  3. Vesicular-arbuscular mycorrhizae in jojoba and mariola

    Energy Technology Data Exchange (ETDEWEB)

    Bloss, H E

    1975-01-01

    Glomus fasculatus was isolated from soil and roots of the indigenous desert plants Parthenium incanum and Simmondsia chinensis, possible sources of rubber and a waxy oil, respectively. It is suggested that inoculation of these plants with mycorrhizal G. spp. could enhance their productivity under cultivation.

  4. The Effect of Vesicular Arbuscular Mycorrhizal (VAM on Yield and Yield Components of Three Sorghum (Sorghum bicolor Cultivars

    Directory of Open Access Journals (Sweden)

    A. Mehraban

    2012-10-01

    Full Text Available To evaluate the influence of vesicular arbuscular mycorrhizal (VAM on yield and yield components of three sorghum cultivars, a factorial experiment based randomized complete block design with four replications was carried out in 2007, at the Agricultural Research Center of Zahak, Iran. The treatments were different mycorrhiza species in three levels: without mycorrhiza (M1, Glomus etanicatum (M2 and G. mosseae(M3 and three cultivars of sorghum: local cultivars (C1, KGS25 (C2 and KGS29 (C3. The results showed that all of the traits measured were increased by inoculation of cultivars with mycorrhiza. The highest plant height (165.1 cm, stem diameter (1.61 cm, flag leaf length (27.22 cm, flag leaf width (3.67 cm and ear width (5.00 cm was obtained by inoculation of seed with Glumus etanicatum, and highest ear length (19.21 cm, ear number (2.51, seed number per ear (10252.11, 1000-seed weight (17.56 g and grain yield (1967.32 kg/ha by using Glumus mossea. The highest leaf width and length belonged to local cultivar, and the highest seed yield to KGS 29 cultivar. However, differences of other traits among sorghum cultivars were not significant. Based on the experimental results it can be concluded that highest grain yield may be obtained by inoculating seeds of KGS 29 with Glumus mossea.

  5. Vesicular-arbuscular mycorrhizal populations in stored topsoil

    Energy Technology Data Exchange (ETDEWEB)

    Harris, J.A.; Hunter, D.; Birch, P.; Short, K.C. (North East London Polytechnic, London (UK). Environment and Industry Research Unit, Dept. of Biology and Biochemistry)

    1987-01-01

    Two soil stores of different ages were sampled to investigate their vesicular-arbuscular mycorrhizal (VAM) populations. The soils collected were assessed for pH, moisture content, loss on ignition, spore numbers, number and size of root fragments present and percentage of these roots infected with VAM. A corn-root bioassay was used to determine soil infectivity. Root fragment number, size, % root infection and soil infectivity were negatively correlated with soil depth. VAM spore number was not significantly correlated with depth in either store. It appears that infected root fragments and fresh roots were the source of inoculum although there may have been a contribution from spores in the younger store. The infectivity of the older store soil was less than that of the younger store. 12 refs., 5 tabs.

  6. Initial vesicular-arbuscular mycorrhizal development of slender wheatgrass on two amended mine spoils

    Energy Technology Data Exchange (ETDEWEB)

    Zak, J.C.; Parkinson, D. (University of Calgary, Calgary, AB (Canada). Dept. of Biology)

    1982-01-01

    The initial vesicular-arbuscular (VA) mycorrhizal development of slender wheatgrass on extracted oil-sands and subalpine coal-mine spoils, amended with either fertilizer, peat, or liquid sewage sludge, was examined. Plants were sampled at 2,6 and 10 weeks after plant emergence and the level of infection was expressed as length of mycorrhizal root per plant and length of root which contained arbuscules, vesicles, or only hyphae. Mycorrhizal infection of slender wheatgrass on the oil sands was limited to plants on the peat-amended spoil. Infection of plants on the peat-amended oil-sands spoil was detected by 2 weeks. Plants on the subalpine spoil were infected at 2 weeks only on the peat-amended spoil. While slender wheatgrass on the control and fertilizer-amended spoil developed mycorrhizae by 6 weeks, infection was not observed in plants on the sewage-amended spoil until 10 weeks. At 10 weeks, there were no significant differences in lengths of mycorrhizal root per plant among the amendments. Increased P levels in the fertilizer- and sewage-amended subalpine spoil did not suppress VA mycorrhizal development. 43 refs., 6 tabs.

  7. EFFECT OF ARBUSCULAR MYCORRHIZA FUNGI INOCULATION ON TEAK (Tectona grandis Linn. F AT CIKAMPEK, WEST JAVA

    Directory of Open Access Journals (Sweden)

    Ragil S.B. Irianto

    2005-07-01

    Full Text Available The aim of this study was to identify the effect of Arbuscular Mycorhiza Fungi (AMF on the early growth of teak (Tectona grandis Linn. F plantation. Teak seedlings were inoculated with Glomus aggregatum or Mycofer (mixing of four Arbuscular Mycorrhiza Fungi (AMF : G. margarita, G. manihotis, G. etunicatum and Acalospora spinosa at the time of transplantation. At  three months old the seedlings were planted in Cikampek experimental forest. Results showed that application of G. aggregatum or mycofer to teak could accelerate height and diameter growth by up to 61%and4 7%, respectively, after three months in the field.

  8. 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 OBOR OECD: Microbiology Impact factor: 4.298, year: 2016

  9. 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.

  10. Effects of arbuscular mycorrhizae on microbial population and ...

    African Journals Online (AJOL)

    Arbuscular mycorrhizal (AM) fungi are ubiquitous fungi distributed widely in soil ecosystems. It has been showed that AM fungi play an important role in improving soil nutrition and enhancing crop disease resistance, which have great application potentials in overcoming crop replant problems. In order to evaluate the effects ...

  11. [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.

  12. Sheared-root inocula of vesicular-arbuscular mycorrhizal fungi.

    Science.gov (United States)

    Sylvia, D M; Jarstfer, A G

    1992-01-01

    For efficient handling, vesicular-arbuscular mycorrhizal fungi should be processed into small and uniform inocula; however, processing can reduce the inoculum density. In this article we describe the preparation and use of sheared-root inocula of Glomus spp. in which inoculum densities were increased during processing. Our objectives were to determine inoculum viability and density after shearing and to ascertain if the sheared inocula could be pelletized or used with a gel carrier. Root samples were harvested from aeroponic cultures, blotted dry, cut into 1-cm lengths, and sheared in a food processor for up to 80 s. After shearing, the inoculum was washed over sieves, and the propagule density in each fraction was determined. Sheared inocula were also encapsulated in carrageenan or used in a gel carrier. Shearing aeroponically produced root inocula reduced particle size. Propagule density increased with decreasing size fraction down to a size of 63 mum, after which propagule density decreased. The weighted-average propagule density of the inoculum was 135,380 propagules g (dry weight) of sheared root material. Sheared roots were encapsulated successfully in carrageenan, and the gel served as an effective carrier. Aeroponic root inoculum was stored dry at 4 degrees C for 23 months without significant reduction in propagule density; however, this material was not appropriate for shearing. Moist roots, useful for shearing, began to lose propagule density after 1 month of storage. Shearing proved to be an excellent method to prepare viable root inocula of small and uniform size, allowing for more efficient and effective use of limited inoculum supplies.

  13. Effect of arbuscular mycorrhiza on the growth and development of micropropagated Annona cherimola plants

    Directory of Open Access Journals (Sweden)

    Concepcion Azcón-Aguilar

    1994-05-01

    Full Text Available Annona cherimola Mill., cherimoya, is a tropical plantation crop of interest in fruit culture. Micropropagation techniques have been developed due to the need to increase productivity through clonal selection. Because of the mycorrhizal dependence exhibited by this crop for optimal growth and the recognized role of mycorrhiza establishment for the survival and development of most of the plants produced in vitro, the effect of mycorrhiza inoculation on the development of micropropagated plants of Annona cherimola was investigated. Mycorrhizal inoculation was assayed at two different stages of the micropropagation process: (i immediately after the in vitro phase, before starting the acclimatization period, and (ii after the acclimatization phase, before starting the post-acclimatization period under greenhouse conditions. Plantlet survival was about 50 % after the acclimatization period. Plant growth and development profited remarkably from mycorrhiza establishment. Most of the arbuscular mycorrhizal fungi (AMF assayed greatly increased shoot and root biomass and leaf area. Micropropagated Annona plants seem to be more dependent on mycorrhiza formation for optimal growth than plants derived from seeds. The greatest effects of AMF on plant growth were observed when they were introduced after the acclimatization period.

  14. Vescicular-arbuscular mycorrhiza and Azospirillum brasilense rhizocoenosis in pearlmillet in a semi-arid soil

    International Nuclear Information System (INIS)

    Tilak, K.V.B.R.; Sachdev, M.S.; Sachdev, Pamila

    2007-01-01

    A field experiment was conducted in an alluvial sandy loam soil using Pearlmillet as the test crop to study the effect of Vescicular-Arbuscular Mycorrhiza (VAM) and Azospirillum with phosphorus on yield and other parameters. Dual inoculation gave a significant increase in Azospirillum and VAM infection in root over the control plants, and resulted in significant increase in grain yield. Combined inoculation alongwith N and P application showed maximum P uptake. Nitrogen fixation increased with plant growth with dually inoculated N and P treatment, The effect was more pronounced in the presence of phosphrous indicating that P is required for nitrogen fixation. (author)

  15. 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.

  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. Stimulation of vesicular-arbuscular mycorrhizal fungi by mycotrophic and nonmycotrophic plant root systems.

    Science.gov (United States)

    Schreiner, R P; Koide, R T

    1993-08-01

    Transformed root cultures of three nonmycotrophic and one mycotrophic plant species stimulated germination and hyphal growth of the vesicular-arbuscular mycorrhizal fungus Glomus etunicatum (Becker & Gerd.) in a gel medium. However, only roots of the mycotrophic species (carrot) supported continued hyphal exploration after 3 to 4 weeks and promoted appressoria formation by G. etunicatum.

  18. Stimulation of Vesicular-Arbuscular Mycorrhizal Fungi by Mycotrophic and Nonmycotrophic Plant Root Systems

    OpenAIRE

    Schreiner, R. Paul; Koide, Roger T.

    1993-01-01

    Transformed root cultures of three nonmycotrophic and one mycotrophic plant species stimulated germination and hyphal growth of the vesicular-arbuscular mycorrhizal fungus Glomus etunicatum (Becker & Gerd.) in a gel medium. However, only roots of the mycotrophic species (carrot) supported continued hyphal exploration after 3 to 4 weeks and promoted appressoria formation by G. etunicatum.

  19. ARBUSCULAR MYCORRHIZA FUNGI AS AN INDICATOR OF SOIL FERTILITY

    Directory of Open Access Journals (Sweden)

    Muhammad Akhid Syibli

    2014-02-01

    Full Text Available Arbuscular mycorrhizal fungi (AMF are ubiquitous organism that forms association with the root of most terrestrial plants. AMF association also influence soil fertility through the enhancement of chemical, biological and physical content. In this study, we enumerated AMF spores from rhizosphere of Tithonia difersivolia as an indicator of soil fertility. The results showed that the most fertile soil had the highest AMF spores density. This research has confirmed that AMF has high interaction with organic carbon, organic matter, total phosphorus, cation exchange capacity, water level, soil fungi and soil bacteria. Partial regression analysis revealed the mathematic equation for their interaction. This equation used the abundant of AMF spores as an indicator for chemical, biological and physical fertility of the soil.

  20. 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.

  1. 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.

  2. Cadmium accumulation in sunflower plants influenced by arbuscular mycorrhiza.

    Science.gov (United States)

    de Andrade, Sara Adrián López; da Silveira, Adriana Parada Dias; Jorge, Renato Atílio; de Abreu, Mônica Ferreira

    2008-01-01

    In order to investigate the cadmium (Cd) accumulation patterns and possible alleviation of Cd stress by mycorrhization, sunflower plants (Helianthus annuus L.) were grown in the presence or absence of Cd (20 micromol L(-1)) and inoculated or not inoculated with the arbuscular mycorrhizal fungus (AMF) Glomus intraradices. No visual symptoms of Cd phytotoxicity were observed; nevertheless, in non-mycorrhizal plants the presence of Cd decreased plant growth. The addition of Cd had no significant effect on either mycorrhizal colonization or the amount of extra-radical mycelia that was produced by the AMF. Cd accumulated mainly in roots; only 22% of the total Cd absorbed was translocated to the shoots, where it accumulated to an average of 228 mg Cd kg(-1). Although the shoot-to-root ratio of Cd was similar in both the AMF inoculated and non-inoculated plants, the total absorbed Cd was 23% higher in mycorrhizal plants. Cd concentration in AMF extra-radical mycelium was 728 microg g(-1) dry weight. Despite the greater absorption of Cd, mycorrhizal plants showed higher photosynthetic pigment concentrations and shoot P contents. Cd also influenced mineral nutrition, leading to decreased Ca and Cu shoot concentrations; N, Fe and Cu shoot contents; and increased S and K shoot concentrations. Cd induced guaiacol peroxidase activity in roots in both mycorrhizal and non-mycorrhizal plants, but this increase was much more accentuated in non-mycorrhizal roots. In conclusion, sunflower plants associated with G. intraradices were less sensitive to Cd stress than non-mycorrhizal plants. Mycorrhizal sunflowers showed enhanced Cd accumulation and some tolerance to excessive Cd concentrations in plant tissues.

  3. 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.

  4. Identification of a Vesicular-Arbuscular Mycorrhizal Fungus by Using Monoclonal Antibodies in an Enzyme-Linked Immunosorbent Assay †

    OpenAIRE

    Wright, Sara F.; Morton, Joseph B.; Sworobuk, Janis E.

    1987-01-01

    Spore morphology is currently used to identify species of vesicular-arbuscular mycorrhizal fungi. We report the first use of a highly specific immunological method for identification of a vesicular-arbuscular mycorrhizal fungus. Two monoclonal antibodies were produced against Glomus occultum. Monoclonal antibodies reacted strongly with both spores and hyphae in an indirect enzyme-linked immunosorbent assay. All other mycorrhizal (29 species) and nonmycorrhizal (5 species) fungi tested were no...

  5. Arbuscular mycorrhizae under CuSO4 stress community structure of arbuscular mycorrhizae under CuSO4 stress in Capsicum annuum L. and Zea mays L

    International Nuclear Information System (INIS)

    Raza, A.; Chaudhry, M.S.

    2017-01-01

    Community structure and ecology of arbuscular mycorrhizal fungi was studied in the present study using two host plant species i.e. Capsicum annuum L. and Zea mays L. under CuSO4 stress. Five levels of copper sulfate (CuSO4) i.e. 0 ppm (control), 25 ppm, 50 ppm, 75 ppm, and 100 ppm were used to elucidate their influence on mycorrhizal community. Results showed that some spores disappeared with increased metal content while other spores were abundant even at a high level of stress. Present studies supported the stress tolerance mechanism conferred by AMF spore density and diversity. Value of Simpson index was shown to decrease from 3.58 to 2.42. Shannon index value was changed from 0.27 to 0.51. Similar rise in the values was observed for spore diversity i.e. 20.94 to 79.13. However, it may be concluded that spore ecotypes might vary in their abundance depending upon the host plant and soil physical-chemical characters that control the metal availability to plants. Among all the four plant varieties, ghotki chilli seemed to have less species associated with it. It can be concluded that when compared to the control, more mycorrhizal types were found to be associated with plants under stress which could prove the tolerance of mycorrhizae against the heavy metals and their positive role in protecting plant from the toxicity of heavy metals. (author)

  6. Effect of gamma irradiation on plants in interaction with arbuscular mycorrhizae

    International Nuclear Information System (INIS)

    Ene, M.; Trandafir, L.; Alexandru, M.

    2009-01-01

    Arbuscular mycorrhizae are endogenous fungi that form symbiotic association with the vast majority of vascular plants. They help to increase the nutrient uptake, especially phosphorus and to exploit a larger area of soil. Also,they improve soil aggregation, contribute to nutrient cycling processes in plants and improve their tolerance of heavy metal contamination or drought, as well as their susceptibility to root pathogens or herbivores. These fungi colonize the root epidermis and outer cortical layers and release bioactive molecules. The transcriptome and the proteome of plants are substantially altered. They have evolved multiple mechanisms that result in improvements in plant resistance to disease and plant growth and productivity, being included in a lot of combination of biofertilizers. In order to study these mechanisms, gamma irradiation was used to create mutants that are defective in their association. Culture under in vitro conditions is presented as method for maintaining the useful mutants in pure line. (authors)

  7. Arbuscular mycorrhiza and their effect on the soil structure in farms with agroecological and intensive management

    Directory of Open Access Journals (Sweden)

    Juan David Lozano Sánchez

    2015-10-01

    Full Text Available Arbuscular mycorrhizal fungi help to reduce the damage caused by erosion and maintain soil structure through the production of mycelium and adhering substances. This study evaluated the structural stability; estimated the diversity and density of mycorrhizal spores present in three systems of soil (eroded, forest and coffee plantations in the rural area of Dagua, Valle del Cauca, Colombia. The systems evaluated were classified as farms with intensive or agroecological management. There were 25 morphospecies of mycorrhiza grouped in 13 genera, being Glomus and Entrophospora the most representative. The mean index values of mean weight (DPM and geometric (DGM diameters and diversity of mycorrhizal spores were statistically higher in farms with agroecological management than in farms with intensive management. The aggregate stability analysis revealed that eroded soils have significantly lower stability than forest and crop soils. A statistically significant correlation was found between diversity (r = 0.579 and spore density (r = 0.66 regarding DGM, and DPM with Shannon diversity (r = 0.54. Differences in practices, use and soil management affect mycorrhizal diversity found on farms and its effect such as particle aggregation agent generates remarkable changes in the stability and soil structure of evaluated areas. It is concluded, that agroecological management tends to favour both mycorrhizae and the structure of soils.

  8. Increased Sporulation of Vesicular-Arbuscular Mycorrhizal Fungi by Manipulation of Nutrient Regimens †

    OpenAIRE

    Douds, David D.; Schenck, N. C.

    1990-01-01

    Adjustment of pot culture nutrient solutions increased root colonization and sporulation of vesicular-arbuscular mycorrhizal (VAM) fungi. Paspalum notatum Flugge and VAM fungi were grown in a sandy soil low in N and available P. Hoagland nutrient solution without P enhanced sporulation in soil and root colonization of Acaulospora longula, Scutellospora heterogama, Gigaspora margarita, and a wide range of other VAM fungi over levels produced by a tap water control or nutrient solutions contain...

  9. Airstream Fractionation of Vesicular-Arbuscular Mycorrhizal Fungi: Concentration and Enumeration of Propagules

    OpenAIRE

    Tommerup, Inez C.

    1982-01-01

    Spores and fragments of vesicular-arbuscular mycorrhizal fungi in dry soils were concentrated up to 100-fold when the soils were partitioned by fluidization and elutriation with a series of upward airstreams at progressively increasing velocities. The propagules were transported with the finer soil particles according to their equivalent spherical diameters. The system was used to predict the transport of propagules by wind. Concentrated propagules were rapidly separated from the soil particl...

  10. 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.

  11. Arbuscular Mycorrhiza Improves Substrate Hydraulic Conductivity in the Plant Available Moisture Range Under Root Growth Exclusion.

    Science.gov (United States)

    Bitterlich, Michael; Franken, Philipp; Graefe, Jan

    2018-01-01

    Arbuscular mycorrhizal fungi (AMF) proliferate in soils and are known to affect soil structure. Although their contribution to structure is extensively investigated, the consequences of those processes for soil water extractability and transport has, so far, gained surprisingly little attention. Therefore we asked, whether AMF can affect water retention and unsaturated hydraulic conductivity under exclusion of root ingrowth, in order to minimize plant driven effects. We carried out experiments with tomato inoculated with Rhizoglomus irregulare in a soil substrate with sand and vermiculite that created variation in colonization by mixed pots with wild type (WT) plants and mycorrhiza resistant (RMC) mutants. Sampling cores were introduced and used to assess substrate moisture retention dynamics and modeling of substrate water retention and hydraulic conductivity. AMF reduced the saturated water content and total porosity, but maintained air filled porosity in soil spheres that excluded root ingrowth. The water content between field capacity and the permanent wilting point (6-1500 kPa) was only reduced in mycorrhizal substrates that contained at least one RMC mutant. Plant available water contents correlated positively with soil protein contents. Soil protein contents were highest in pots that possessed the strongest hyphal colonization, but not significantly affected. Substrate conductivity increased up to 50% in colonized substrates in the physiologically important water potential range between 6 and 10 kPa. The improvements in hydraulic conductivity are restricted to substrates where at least one WT plant was available for the fungus, indicating a necessity of a functional symbiosis for this effect. We conclude that functional mycorrhiza alleviates the resistance to water movement through the substrate in substrate areas outside of the root zone.

  12. 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.

  13. 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.

  14. 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

  15. 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.

  16. Identification of a vesicular-arbuscular mycorrhizal fungus by using monoclonal antibodies in an enzyme-linked immunosorbent assay.

    Science.gov (United States)

    Wright, S F; Morton, J B; Sworobuk, J E

    1987-09-01

    Spore morphology is currently used to identify species of vesicular-arbuscular mycorrhizal fungi. We report the first use of a highly specific immunological method for identification of a vesicular-arbuscular mycorrhizal fungus. Two monoclonal antibodies were produced against Glomus occultum. Monoclonal antibodies reacted strongly with both spores and hyphae in an indirect enzyme-linked immunosorbent assay. All other mycorrhizal (29 species) and nonmycorrhizal (5 species) fungi tested were nonreactive with the monoclonal antibodies. A single spore of G. occultum was detectable in the presence of high numbers of spores of other vesicular-arbuscular mycorrhizal fungi. Variation in the reaction of G. occultum isolates from West Virginia, Florida, and Colombia suggests that monoclonal antibodies may differentiate strains.

  17. Quantitative Simulation of Damage Roots on Inoculated Alfalfa by Arbuscular Mycorrhiza Fungi

    Directory of Open Access Journals (Sweden)

    Ying Liu

    2017-12-01

    Full Text Available Underground mining would cause ground subsidence damage and large amounts of cracks, which would result a loss of surface moisture and nutrient and intensifying drought. There are a few reports about damage to plant roots caused by coal mining. The irregular distribution of plant roots in soil and the different forces generated in process of surface subsidence are difficult to study comprehensively. The technologies to repair damaged plant roots have not been completely perfected yet. Based on quantitative simulation of alfalfa root cut-repair experiment, this paper discusses the influences of inoculated Arbuscular Mycorrhiza Fungi on alfalfa root and the mitigation effects of an inoculation on the growth of alfalfa. Root injured alfalfa were investigated by soil pot experiments. The result indicated that at the same cut degree, the growth situation of inoculated alfalfa is better than the contrast. Compared with the Olsen-P content, at cut level of 0 and 1/3, the sand of inoculated alfalfa has less Olsen-P than contrast, at cut degree of 1/2 and 2/3, the sand of inoculated alfalfa has more Olsen-P than contrast, at degree of 3/4, the sand of inoculated alfalfa has less Olsen-P than contrast, the change trend of Olsen-P content is concerned with the relative strength size of absorb Olsen-P by alfalfa root and dissolve Olsen-P by root exudates and hyphae interstate.

  18. The Medicago truncatula GRAS protein RAD1 supports arbuscular mycorrhiza symbiosis and Phytophthora palmivora susceptibility.

    Science.gov (United States)

    Rey, Thomas; Bonhomme, Maxime; Chatterjee, Abhishek; Gavrin, Aleksandr; Toulotte, Justine; Yang, Weibing; André, Olivier; Jacquet, Christophe; Schornack, Sebastian

    2017-12-16

    The roots of most land plants are colonized by symbiotic arbuscular mycorrhiza (AM) fungi. To facilitate this symbiosis, plant genomes encode a set of genes required for microbial perception and accommodation. However, the extent to which infection by filamentous root pathogens also relies on some of these genes remains an open question. Here, we used genome-wide association mapping to identify genes contributing to colonization of Medicago truncatula roots by the pathogenic oomycete Phytophthora palmivora. Single-nucleotide polymorphism (SNP) markers most significantly associated with plant colonization response were identified upstream of RAD1, which encodes a GRAS transcription regulator first negatively implicated in root nodule symbiosis and recently identified as a positive regulator of AM symbiosis. RAD1 transcript levels are up-regulated both in response to AM fungus and, to a lower extent, in infected tissues by P. palmivora where its expression is restricted to root cortex cells proximal to pathogen hyphae. Reverse genetics showed that reduction of RAD1 transcript levels as well as a rad1 mutant are impaired in their full colonization by AM fungi as well as by P. palmivora. Thus, the importance of RAD1 extends beyond symbiotic interactions, suggesting a general involvement in M. truncatula microbe-induced root development and interactions with unrelated beneficial and detrimental filamentous microbes. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  19. 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

  20. [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

    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...

  1. 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.

  2. Partitioning of Intermediary Carbon Metabolism in Vesicular-Arbuscular Mycorrhizal Leek.

    Science.gov (United States)

    Shachar-Hill, Y.; Pfeffer, P. E.; Douds, D.; Osman, S. F.; Doner, L. W.; Ratcliffe, R. G.

    1995-05-01

    Vesicular-arbuscular mycorrhizal fungi are symbionts for a large variety of crop plants; however, the form in which they take up carbon from the host is not established. To trace the course of carbon metabolism, we have used nuclear magnetic resonance spectroscopy with [13C]glucose labeling in vivo and in extracts to examine leek (Allium porrum) roots colonized by Glomus etunicatum (and uncolonized controls) as well as germinating spores. These studies implicate glucose as a likely substrate for vesicular-arbuscular mycorrhizal fungi in the symbiotic state. Root feeding of 0.6 mM 1-[13C]glucose labeled only the fungal metabolites trehalose and glycogen. The time course of this labeling was dependent on the status of the host. Incubation with 50 mM 1-[13C]glucose caused labeling of sucrose (in addition to fungal metabolites) with twice as much labeling in uncolonized plants. There was no detectable scrambling of the label from C1 glucose to the C6 position of glucose moieties in trehalose or glycogen. Labeling of mannitol C1,6 in the colonized root tissue was much less than in axenically germinating spores. Thus, carbohydrate metabolism of host and fungus are significantly altered in the symbiotic state.

  3. Interaction of rhizosphere bacteria, fertilizer, and vesicular-arbuscular mycorrhizal fungi with sea oats.

    Science.gov (United States)

    Will, M E; Sylvia, D M

    1990-07-01

    Plants must be established quickly on replenished beaches in order to stabilize the sand and begin the dune-building process. The objective of this research was to determine whether inoculation of sea oats (Uniola paniculata L.) with bacteria (indigenous rhizosphere bacteria and N(2) fixers) alone or in combination with vesicular-arbuscular mycorrhizal fungi would enhance plant growth in beach sand. At two fertilizer-N levels, Klebsiella pneumoniae and two Azospirillum spp. did not provide the plants with fixed atmospheric N; however, K. pneumoniae increased root and shoot growth. When a sparingly soluble P source (CaHPO(4)) was added to two sands, K. pneumoniae increased plant growth in sand with a high P content. The phosphorus content of shoots was not affected by bacterial inoculation, indicating that a mechanism other than bacterially enhanced P availability to plants was responsible for the growth increases. When sea oats were inoculated with either K. pneumoniae or Acaligenes denitrificans and a mixed Glomus inoculum, there was no consistent evidence of a synergistic effect on plant growth. Nonetheless, bacterial inoculation increased root colonization by vesicular-arbuscular mycorrhizal fungi when the fungal inoculum consisted of colonized roots but had no effect on colonization when the inoculum consisted of spores alone. K. pneumoniae was found to increase spore germination and hyphal growth of Glomus deserticola compared with the control. The use of bacterial inoculants to enhance establishment of pioneer dune plants warrants further study.

  4. Role of the GRAS transcription factor ATA/RAM1 in the transcriptional reprogramming of arbuscular mycorrhiza in Petunia hybrida

    OpenAIRE

    Rich, Melanie K.; Courty, Pierre-Emmanuel; Roux, Christophe; Reinhardt, Didier

    2017-01-01

    Background Development of arbuscular mycorrhiza (AM) requires a fundamental reprogramming of root cells for symbiosis. This involves the induction of hundreds of genes in the host. A recently identified GRAS-type transcription factor in Petunia hybrida, ATA/RAM1, is required for the induction of host genes during AM, and for morphogenesis of the fungal endosymbiont. To better understand the role of RAM1 in symbiosis, we set out to identify all genes that depend on activation by RAM1 in mycorr...

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

    International Nuclear Information System (INIS)

    Gucwa-Przepiora, Ewa; Malkowski, Eugeniusz; Sas-Nowosielska, Aleksandra; Kucharski, Rafal; Krzyzak, Jacek; Kita, Andrzej; Roemkens, Paul 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 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. - Addition of phosphorus and lignite in chemophytostabilization increased arbuscular mycorrhizal colonization of Deschampsia cespitosa roots

  6. 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

  7. 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

    2017-10-01

    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.

  8. The Petunia GRAS Transcription Factor ATA/RAM1 Regulates Symbiotic Gene Expression and Fungal Morphogenesis in Arbuscular Mycorrhiza1

    Science.gov (United States)

    Rich, Mélanie K.

    2015-01-01

    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. PMID:25971550

  9. 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.

  10. Computational investigation of small RNAs in the establishment of root nodules and arbuscular mycorrhiza in leguminous plants.

    Science.gov (United States)

    Jin, Danfeng; Meng, Xianwen; Wang, Yue; Wang, Jingjing; Zhao, Yuhua; Chen, Ming

    2018-01-03

    Many small RNAs have been confirmed to play important roles in the development of root nodules and arbuscular mycorrhiza. In this study, we carried out the identification of certain small RNAs in leguminous plants (Medicago truncatula, soybean, peanut and common bean), such as miRNAs, tRFs and srRNAs, as well as the computational investigation of their regulations. Thirty miRNAs were predicted to be involved in establishing root nodules and mycorrhiza, and 12 of them were novel in common bean and peanut. The generation of tRFs in M. truncatula was not associated with tRNA gene frequencies and codon usage. Six tRFs exhibited different expressions in mycorrhiza and root nodules. Moreover, srRNA 5.8S in M. truncatula was generated from the regions with relatively low conservation at the rRNA 3' terminal. The protein-protein interactions between the proteins encoded by the target genes of miRNAs, tRFs and srRNAs were computed. The regulation of these three types of sRNAs in the symbiosis between leguminous plants and microorganisms is not a single regulation of certain signaling or metabolic pathways but a global regulation for the plants to own growth or specific events in symbiosis.

  11. Phosphorus use efficiency of tomato as influenced by phosphorus and vesicular arbuscular mycorrhizal (VAM) fungi inoculation

    International Nuclear Information System (INIS)

    Dhinakaran, R.; Savithri, P.

    1997-01-01

    A pot experiment was conducted on tomato (Lycopersicon esculentum L.var. CO3) grown in red non-calcareous soil (Paralythic Ustochrept) to study the effect of different P treatments involving single superphosphate (SSP) and Mussoorie rock phosphate (MRP) added at different levels, viz. 100 and 75 kg P 2 O 5 /ha along with and without vesicular arbuscular mycorrhizal (VAM) fungi inoculation. The results revealed that the P application as superphosphate at 100 kg P 2 O 5 /ha significantly increased the yield of tomato but the application of VAM fungi did not have any pronounced effect on tomato yield. The 32 P studies confirmed the increased uptake of P by the plants at higher level of P application. P content and its uptake by tomato fruit increased with the increasing levels of P application and VAM inoculation. The VAM fungi inoculation was also helpful in increasing the fertilizer use efficiency and also per cent P derived from fertilizer. (author)

  12. Increased sporulation of vesicular-arbuscular mycorrhizal fungi by manipulation of nutrient regimens.

    Science.gov (United States)

    Douds, D D; Schenck, N C

    1990-02-01

    Adjustment of pot culture nutrient solutions increased root colonization and sporulation of vesicular-arbuscular mycorrhizal (VAM) fungi. Paspalum notatum Flugge and VAM fungi were grown in a sandy soil low in N and available P. Hoagland nutrient solution without P enhanced sporulation in soil and root colonization of Acaulospora longula, Scutellospora heterogama, Gigaspora margarita, and a wide range of other VAM fungi over levels produced by a tap water control or nutrient solutions containing P. However, Glomus intraradices produced significantly more spores in plant roots in the tap water control treatment. The effect of the nutrient solutions was not due solely to N nutrition, because the addition of NH(4)NO(3) decreased both colonization and sporulation by G. margarita relative to levels produced by Hoagland solution without P.

  13. Effects of vesicular-arbuscular mycorrhizal (VAM) fungi on the seedling growth of three Pistacia species.

    Science.gov (United States)

    Caglar, S; Akgun, A

    2006-07-01

    The experiment was undertaken to test the efficiency of inoculation of vesicular-arbuscular mycorrhizal (VAM) fungi on the seedling growth of three Pistacia species used as rootstocks. The stratified Pistacia seeds were inoculated with VAM fungi. The highest rate of inoculated roots was 96.7% in P. khinjuck seedlings with G. clarum and G. etunicatum, 83.3% in P. vera seedlings with G. caledonium and 73.3% in P. terebinthus seedlings with G. caledonium. Mycorrhizal inoculations improved seedling height only in P. terebinthus. Certain mycorrhizal inoculations increased the leaf N, but not P and K contents. Seedlings inoculated with G. caledonium had higher reducing sugar contents. It was concluded that pre-inoculated Pistacia seedlings could have a better growth in the harsh field conditions.

  14. Observations on arbuscular mycorrhiza associated with important edible tuberous plants grown in wet evergreen forest in Assam, India

    Directory of Open Access Journals (Sweden)

    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.

  15. Extensive In Vitro Hyphal Growth of Vesicular-Arbuscular Mycorrhizal Fungi in the Presence of CO(2) and Flavonols.

    Science.gov (United States)

    Bécard, G; Douds, D D; Pfeffer, P E

    1992-03-01

    Various flavonoids were tested for their ability to stimulate in vitro growth of germinated spores of vesicular-arbuscular mycorrhizal fungi. Experiments were performed in the presence of 2% CO(2), previously demonstrated to be required for growth of Gigaspora margarita (G. Bécard and Y. Piché, Appl. Environ. Microbiol. 55:2320-2325, 1989). Only the flavonols stimulated fungal growth. The flavones, flavanones, and isoflavones tested were generally inhibitory. Quercetin (10 muM) prolonged hyphal growth from germinated spores of G. margarita from 10 to 42 days. An average of more than 500 mm of hyphal growth and 13 auxiliary cells per spore were obtained. Quercetin also stimulated the growth of Glomus etunicatum. The glycosides of quercetin, rutin, and quercitrin were not stimulatory. The axenic growth of G. margarita achieved here under rigorously defined conditions is the most ever reported for a vesicular-arbuscular mycorrhizal fungus.

  16. 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

  17. Vesicular-arbuscular mycorrhizal status of plant species in the peat swamp forest of Setia Alam Jaya, Sebangau, Central Kalimantan

    Directory of Open Access Journals (Sweden)

    Suciatmih Suciatmih

    2003-06-01

    Full Text Available In order to describe the vesicular-arbuscular mycorrhizal (VAM status of plants growing on peat soil, a study was carried out inthe peat swamp forest of Setia Alam Jaya in Sebangau, Central Kalimantan. Out of 146 plant root samples belonging to 48 plantspecies from 25 families examined, all plants colonized by VAM fungi namely 14 (29.2% high level, 32 (66.7% medium level, and 2(4.1% low level respectively.

  18. Vesicular-arbuscular mycorrhizal status of plant species in the peat swamp forest of Setia Alam Jaya, Sebangau, Central Kalimantan

    OpenAIRE

    Suciatmih Suciatmih

    2003-01-01

    In order to describe the vesicular-arbuscular mycorrhizal (VAM) status of plants growing on peat soil, a study was carried out inthe peat swamp forest of Setia Alam Jaya in Sebangau, Central Kalimantan. Out of 146 plant root samples belonging to 48 plantspecies from 25 families examined, all plants colonized by VAM fungi namely 14 (29.2%) high level, 32 (66.7%) medium level, and 2(4.1%) low level respectively.

  19. 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.

  20. Artificial climate warming positively affects arbuscular mycorrhizae but decreases soil aggregate water stability in an annual grassland

    Energy Technology Data Exchange (ETDEWEB)

    Rillig, M.C.; Wright, S.F.; Shaw, M.R.; Field, C.B.

    2002-04-01

    Despite the importance of arbuscular mycorrhizae to the functioning of terrestrial ecosystems (e.g. nutrient uptake, soil aggregation), and the increasing evidence of global warming, responses of arbuscular mycorrhizal fungi (AMF) to climate warming are poorly understood. In a field experiment using infrared heaters, we found effects of warming on AMF after one growing season in an annual grassland, in the absence of any effects on measured root parameters (weight, length, average diameter). AMF soil hyphal length was increased by over 40% in the warmed plots, accompanied by a strong trend for AMF root colonization increase. In the following year, root weight was again not significantly changed, and AMF root colonization increased significantly in the warmed plots. Concentration of the soil protein glomalin, a glycoprotein produced by AMF hyphae with importance in soil aggregation, was decreased in the warmed plots. Soil aggregate water stability, measured for five diameter size classes, was also decreased significantly. In the following year, soil aggregate weight in two size classes was decreased significantly, but the effect size was very small. These results indicate that ecosystem warming may have stimulated carbon allocation to AMF. Other factors either influenced glomalin decomposition or production, hence influencing the role of these symbionts in soil aggregation. The observed small changes in soil aggregation, if widespread among terrestrial ecosystems, could have important consequences for soil carbon storage and erosion in a warmed climate, especially if there are cumulative effects of warming. (au)

  1. Interactions of Vesicular-Arbuscular Mycorrhizal Fungi, Phosphorus, and Heterodera glycines on Soybean.

    Science.gov (United States)

    Tylka, G L; Hussey, R S; Roncadori, R W

    1991-01-01

    Effects of vesicular-arbuscular mycorrhizal (VAM) fungi and soil phosphorus (P) fertility on parasitism of soybean cultivars Bragg and Wright by soybean cyst nematode (SCN) were investigated in field micropiot and greenhouse experiments. VAM fungi increased height of both cultivars and yield of Wright in microplot studies in 1986 and 1987. Conversely, yield of mycorrhizal and nonmycorrhizal plants of both cultivars was suppressed by SCN. Soil population densities of SCN were unaffected by VAM fungi in 1986 but were greater in microplots infested with VAM fungi than in control microplots in 1987. Growth of Wright soybean was stimulated by VAM fungi and suppressed by SCN in greenhouse experiments. The effect of VAM fungi on SCN varied with time. Numbers of SCN in roots and soil were decreased by VAM fungi by as much as 73% at the highest SCN inoculum level through 49 days after planting. Later, however, SCN numbers were usually comparable on mycorrhizal and nonmycorrhizal plants. Soil P fertility generally had no effect on SCN. Results of a split-root experiment indicated that VAM fungal suppression of SCN was not systemic.

  2. Production of vesicular-arbuscular mycorrhizal fungus inoculum in aeroponic culture.

    Science.gov (United States)

    Hung, L L; Sylvia, D M

    1988-02-01

    Bahia grass (Paspalum notatum) and industrial sweet potato (Ipomoea batatas) colonized by Glomus deserticola, G. etunicatum, and G. intraradices were grown in aeroponic cultures. After 12 to 14 weeks, all roots were colonized by the inoculated vesicular-arbuscular mycorrhizal fungi. Abundant vesicles and arbuscules formed in the roots, and profuse sporulation was detected intra-and extraradically. Within each fungal species, industrial sweet potato contained significantly more roots and spores per plant than bahia grass did, although the percent root colonization was similar for both hosts. Mean percent root colonization and sporulation per centimeter of colonized root generally increased with time, although with some treatments colonization declined by week 14. Spore production ranged from 4 spores per cm of colonized root for G. etunicatum to 51 spores per cm for G. intraradices. Infectivity trials with root inocula resulted in a mean of 38, 45, and 28% of bahia grass roots colonized by G. deserticola, G. etunicatum, and G. intraradices, respectively. The germination rate of G. etunicatum spores produced in soil was significantly higher than that produced in aeroponic cultures (64% versus 46%) after a 2-week incubation at 28 degrees C. However, infectivity studies comparing G. etunicatum spores from soil and aeroponic culture indicated no biological differences between the spore sources. Aeroponically produced G. deserticola and G. etunicatum inocula retained their infectivity after cold storage (4 degrees C) in either sterile water or moist vermiculite for at least 4 and 9 months, respectively.

  3. A plausible mechanism of biosorption in dual symbioses by vesicular-arbuscular mycorrhizal in plants.

    Science.gov (United States)

    Azmat, Rafia; Hamid, Neelofer

    2015-03-01

    Dual symbioses of vesicular-arbuscular mycorrhizal (VAM) fungi with growth of Momordica charantia were elucidated in terms of plausible mechanism of biosorption in this article. The experiment was conducted in green house and mixed inoculum of the VAM fungi was used in the three replicates. Results demonstrated that the starch contents were the main source of C for the VAM to builds their hyphae. The increased plant height and leaves surface area were explained in relation with an increase in the photosynthetic rates to produce rapid sugar contents for the survival of plants. A decreased in protein, and amino acid contents and increased proline and protease activity in VAM plants suggested that these contents were the main bio-indicators of the plants under biotic stress. The decline in protein may be due to the degradation of these contents, which later on converted into dextrose where it can easily be absorbed by for the period of symbioses. A mechanism of C chemisorption in relation with physiology and morphology of plant was discussed.

  4. Ammonia Assimilation in Zea mays L. Infected with a Vesicular-Arbuscular Mycorrhizal Fungus Glomus fasciculatum.

    Science.gov (United States)

    Cliquet, J. B.; Stewart, G. R.

    1993-03-01

    To investigate nitrogen assimilation and translocation in Zea mays L. colonized by the vesicular-arbuscular mycorrhizal (VAM) fungus Glomus fasciculatum (Thax. sensu Gerd.), we measured key enzyme activities, 15N incorporation into free amino acids, and 15N translocation from roots to shoots. Glutamine synthetase and nitrate reductase activities were increased in both roots and shoots compared with control plants, and glutamate dehydrogenase activity increased in roots only. In the presence of [15N]ammonium, glutamine amide was the most heavily labeled product. More label was incorporated into amino acids in VAM plants. The kinetics of 15N labeling and effects of methionine sulfoximine on distribution of 15N-labeled products were entirely consistent with the operation of the glutamate synthase cycle. No evidence was found for ammonium assimilation via glutamate dehydrogenase. 15N translocation from roots to shoots through the xylem was higher in VAM plants compared with control plants. These results establish that, in maize, VAM fungi increase ammonium assimilation, glutamine production, and xylem nitrogen translocation. Unlike some ectomycorrhizal fungi, VAM fungi do not appear to alter the pathway of ammonium assimilation in roots of their hosts.

  5. Interaction of vesicular-arbuscular mycorrhizal fungi with erosion in an oxisol.

    Science.gov (United States)

    Habte, M; Fox, R L; Aziz, T; El-Swaify, S A

    1988-04-01

    The development of vesicular-arbuscular mycorrhizal (VAM) symbiosis was monitored in Leucaena leucocephala grown in an Oxisol subjected to incremental simulated erosion. The density of VAM infective propagules in the soil diminished as the level of simulated erosion (removal of surface soil) was increased from 0 to 50 cm. The level of infection on L. leucocephala roots observed at harvest was not significantly influenced by simulated erosion unless removal of surface soil exceeded 25 cm. Inoculation of this soil and the uneroded soil with Glomus aggregatum enhanced the early onset of infection but did not significantly influence the level of infection observed at the time of harvest. Simulated erosion in excess of 7.5 cm of surface soil removal significantly delayed the development of VAM effectiveness monitored in terms of the P status of L. leucocephala subleaflets and also curtailed the level of maximum effectiveness observed. Decreases in VAM effectiveness were significantly correlated with decreases in soil chemical constituents. However, VAM effectiveness in a soil subjected to 30 cm of surface soil removal was not restored to a significant extent unless the soil was amended with P, even though other nutrients were restored to sufficiency levels. Our results demonstrate that the development of VAM effectiveness is the phase of the VAM symbiosis that is most adversely influenced by simulated erosion and that this effect appears to be caused primarily by insufficient P in the soil solution.

  6. The development of arbuscular mycorrhiza in two simulated stages of spoil-bank succession

    Czech Academy of Sciences Publication Activity Database

    Püschel, David; Rydlová, Jana; Vosátka, Miroslav

    2007-01-01

    Roč. 35, č. 2 (2007), s. 363-369 ISSN 0929-1393 R&D Projects: GA ČR GA526/04/0996; GA ČR(CZ) GD206/03/H137 Institutional research plan: CEZ:AV0Z60050516 Keywords : mycorrhiza * plant succession * spoil bank s Subject RIV: EF - Botanics Impact factor: 1.810, year: 2007

  7. Distribution of vesicular-arbuscular mycorrhizal fungi in coal, lignite and calcite mine spoils of India

    Energy Technology Data Exchange (ETDEWEB)

    Ganesan, V.; Ragupathy, S.; Parthipan, B.; Rani, D.B.R.; Mahadevan, A.

    1991-12-31

    Vesicular-arbuscular mycorhizzal (VAM) status was assessed for coal, lignite and calcite mine spoils. The three study sites were: The Kothagudem coal field in the south central region where waste materials are piled 1 to 2 m high on the soil surface. Samples were collected from plants growing on the waste. Neyveli, on the southeastern coast, is a lignite coal mine where the spoil is piled 70 to 100 m high on the soil surface. Samples were collected from recently revegetated mine spoil and from 25 year old revegetated sites. The calcite mine at Thazhaiyuthu in the south where the spoil is piled up 2 to 3 m on the soil surface. Samples were collected from 4 to 7 year old reclaimed sites. The wastes generally supported different plant species. The level of VAM infection of plants was markedly different in each mine spoil, with the maximum infection in the coal and calcite spoils, and the least in the lignite spoil. There was more infection in the 25 year old lignite spoil than in the newly revegetated spoil. There were different VAM species in each spoil, and no one species was present in all of the samples. The authors conclude that one of the factors leading to the differences between spoils is the amount of topsoil contained in the spoil (least in the lignite spoils which are very deep). The other is age of the spoils. Unfortunately the authors concluded that the best approach is to enrich the spoils with VAM rather than salvaging and replacing topsoil

  8. Interaction of Vesicular-arbuscular Mycorrhizal Fungi and Phosphorus with Meloidogyne incognita on Tomato.

    Science.gov (United States)

    Cason, K M; Hussey, R S; Roncadori, R W

    1983-07-01

    The influence of two vesicular-arbuscular mycorrhizal fungi and phosphorus (P) nutrition on penetration, development, and reproduction by Meloidogyne incognita on Walter tomato was studied in the greenhouse. Inoculation with either Gigaspora margarita or Glomus mosseae 2 wk prior to nematode inoculation did not alter infection by M. incognita compared with nonmycorrhizal plants, regardless of soil P level (either 3 mug [low P] or 30 mug [high P] available P/g soil). At a given soil P level, nematode penetration and reproduction did not differ in mycorrhizal and nonmycorrhizal plants. However, plants grown in high P soil had greater root weights, increased nematode penetration and egg production per plant, and decreased colonization by mycorrhizal fungi, compared with plants grown in low P soil. The number of eggs per female nematode on mycorrhizal and nonmycorrhizal plants was not influenced by P treatment. Tomato plants with split root systems grown in double-compartment containers which had either low P soil in both sides or high P in one side and low P in the other, were inoculated at transplanting with G. margarita and 2 wk later one-half of the split root system of each plant was inoculated with M. incognita larvae. Although the mycoorhizal fungus increased the inorganic P content of the root to a level comparable to that in plants grown in high P soil, nematode penetration and reproduction were not altered. In a third series of experiments, the rate of nematode development was not influenced by either the presence of G. margarita or high soil P, compared with control plants grown in low P soil. These data indicate that supplemental P (30 mu/g soil) alters root-knot nematode infection of tomato more than G. mosseae and G. margarita.

  9. 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

  10. 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 information...

  11. 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

  12. Influence of arbuscular mycorrhizas on the growth rate of mist-propagated olive plantlets

    OpenAIRE

    Porras Piedra, A.; Soriano Martín, M.L.; Porras Soriano, A.; Fernández Izquierdo, G.

    2005-01-01

    The aim of this work was to determine the influence of early inoculation of semi-woody olive cuttings (cv. Cornicabra), cultivated under mist propagation conditions, with arbuscular mycorrhizal fungi. A strongly positive response was seen to root inoculation with the three fungal species tested —Glomus mosseae, G. intraradices and G. claroideum— both in nursery phase plantlets, and in older plants grown in 5 L pots.

  13. Competitive interactions are mediated in a sex-specific manner by arbuscular mycorrhiza in Antennaria dioica

    OpenAIRE

    Varga, S.; Vega-Frutis, R.; Kytöviita, M.-M.; Franken, P.

    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...

  14. Resistance Responses of Potato to Vesicular-Arbuscular Mycorrhizal Fungi under Varying Abiotic Phosphorus Levels.

    Science.gov (United States)

    McArthur, D A; Knowles, N R

    1992-09-01

    In mycorrhizal symbioses, susceptibility of a host plant to infection by fungi is influenced by environmental factors, especially the availability of soil phosphorus. This study describes morphological and biochemical details of interactions between a vesicular-arbuscular mycorrhizal (VAM) fungus and potato (Solanum tuberosum L. cv Russet Burbank) plants, with a particular focus on the physiological basis for P-induced resistance of roots to infection. Root infection by the VAM fungus Glomus fasciculatum ([Thaxt. sensu Gerdemann] Gerdemann and Trappe) was extensive for plants grown with low abiotic P supply, and plant biomass accumulation was enhanced by the symbiosis. The capacity of excised roots from P-deficient plants to produce ethylene in the presence or absence of exogenous 1-amino cyclopropane-1-carboxylic acid (ACC) was markedly reduced by VAM infection. This apparent inhibition of ACC oxidase (ACC(ox)) activity was localized to areas containing infected roots, as demonstrated in split-root studies. Furthermore, leachate from VAM roots contained a potent water-soluble inhibitor of ethylene generation from exogenous ACC by nonmycorrhizal (NM) roots. The leachate from VAM-infected roots had a higher concentration of phenolics, relative to that from NM roots. Moreover, the rates of ethylene formation and phenolic concentration in leachates from VAM roots were inversely correlated, suggesting that this inhibitor may be of a phenolic nature. The specific activity of extracellular peroxidase recovered in root leachates was not stimulated by VAM infection, although activity on a fresh weight basis was significantly enhanced, reflecting the fact that VAM roots had higher protein content than NM roots. Polyphenol oxidase activity of roots did not differ between NM and VAM roots. These results characterize the low resistance response of P-deficient plants to VAM infection. When plants were grown with higher abiotic P supply, the relative benefit of the VAM symbiosis

  15. Influence of Vesicular-Arbuscular Mycorrhizal Fungi on the Response of Potato to Phosphorus Deficiency.

    Science.gov (United States)

    McArthur, DAJ.; Knowles, N. R.

    1993-01-01

    Morphological and biochemical interactions between a vesicular-arbuscular mycorrhizal (VAM) fungus (Glomus fasciculatum [Thaxt. sensu Gerdemann] Gerdemann and Trappe) and potato (Solanum tuberosum L.) plants during the development of P deficiency were characterized. Nonmycorrhizal (NM) plants grown for 63 d with low abiotic P supply (0.5 mM) produced 34, 52, and 73% less root, shoot, and tuber dry matter, respectively, than plants grown with high P (2.5 mM). The total leaf area and the leaf area:plant dry weight ratio of low-P plants were substantially lower than those of high-P plants. Moreover, a lower shoot:root dry weight ratio and tuber:plant dry weight ratio in low-P plants than in high-P plants characterized a major effect of P deficiency stress on dry matter partitioning. In addition to a slower rate of growth, low-P plants accumulated nonreducing sugars and nitrate. Furthermore, root respiration and leaf nitrate reductase activity were lower in low-P plants than in high-P plants. Low abiotic P supply also induced physiological changes that contributed to the greater efficiency of P acquisition by low-P plants than by high-P plants. For example, allocation of dry matter and P to root growth was less restricted by P deficiency stress than to shoot and tuber growth. Also, the specific activities of root acid phosphatases and vanadate-sensitive microsomal ATPases were enhanced in P-deficient plants. The establishment of a VAM symbiosis by low-P plants was essential for efficient P acquisition, and a greater root infection level for P-stressed plants indicated increased compatibility to the VAM fungus. By 63 d after planting, low-P VAM plants had recovered 42% more of the available soil P than low-P NM plants. However, the VAM fungus only partially alleviated P deficiency stress and did not completely compensate for inadequate abiotic P supply. Although the specific activities of acid phosphatases and microsomal ATPases were only marginally influenced by VAM

  16. The incidence of arbuscular mycorrhiza in two submerged Isoëtes species

    Czech Academy of Sciences Publication Activity Database

    Sudová, Radka; Rydlová, Jana; Čtvrtlíková, Martina; Havránek, P.; Adamec, Lubomír

    2011-01-01

    Roč. 94, č. 4 (2011), s. 183-187 ISSN 0304-3770. [The Biology of Fungi. IMC9. Edinburgh, (01.08.2010-06.08.2010)] R&D Projects: GA ČR GAP504/10/0781; GA ČR GA206/07/1200 Institutional research plan: CEZ:AV0Z60050516; CEZ:AV0Z60170517 Keywords : arbuscular mycorrhizal fungi * aquatic macrophytes * dark septate endophytes Subject RIV: EF - Botanics Impact factor: 1.516, year: 2011

  17. 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

    The effect of the fungicides carbendazim, fenpropimorph and propiconazole and of the insecticide dimethoate on plant P uptake via external hyphae of arbuscular mycorrhizal (AM) fungi was examined. Mycorrhizal plants were grown in a two-compartment system where a root-free hyphal compartment...... 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...

  18. 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.

  19. Field inoculation of arbuscular mycorrhiza on maize (Zea mays L. under low inputs: preliminary study on quantitative and qualitative aspects

    Directory of Open Access Journals (Sweden)

    Emilio Sabia

    2015-03-01

    Full Text Available Arbuscular mycorrhizal symbiosis contributes to the sustainability of soil-plant system. A field experiment was conducted to examine the effect of arbuscular mycorrhiza (AM on quantitative and qualitative performance in forage maize (Zea mays L.. Within the project Sviluppo di modelli zootecnici ai fini della sostenibilità (SOS-ZOOT a trial was conducted at the experimental farm of the Agricultural Research Council in Bella (PZ, located in Basilicata region (Southern Italy at 360 m asl, characterised by an annual rainfall of approximately 650 mm. For spring sowing, two plots of 2500 m2 were used, one sown with seeds inoculated with AM (M, 1.0 kg/ha, and the other one with non-inoculated seeds (NM. After 120 days after sowing, when plants showed 30% dry matter, five replicates of 1 m2 per plot were used to estimate dry matter yield (DMY, while half plot was dedicated to the assessment of grain production. For each replicate, three representative plants were considered; each plant was measured for height and was divided into leaves, stem and ear. For each plot, the following constituents were determined: crude protein, ash, ether extract, crude fibre (CF, fractions of fibre [neutral detergent (NDF, acid detergent fibre (ADF and sulphuric acid lignin] and phosphorus (P. Throughout the period of plants’ growth, no herbicides, organic or inorganic fertilisation, and irrigation water were distributed. The preliminary results revealed a significant effect of AM inoculation on forage maize DMY, P content in the whole plant, into the leaves and on the quality of steam. The M thesis showed a significant increase in terms of DMY in comparison with the NM thesis: 21.2 vs 17.9 t/ha (P<0.05. The mycorrhized whole plants [0.22 vs 0.17% dry matter (DM, P<0.05] and leaves (0.14 vs 0.09% DM, P<0.05 showed an increased P content. The stems of M plants showed a content of CF, NDF, ADF and Ash significantly lower compared with NM plants. No significant

  20. Effects of biochar and Arbuscular mycorrhizae on bioavailability of potentially toxic elements in an aged contaminated soil

    International Nuclear Information System (INIS)

    Qiao, Yuhui; Crowley, David; Wang, Kun; Zhang, Huiqi; Li, Huafen

    2015-01-01

    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. - Highlights: • Biochar pyrolyzed from corn stalks at 300 °C/500 °C can increase the biomass of corn growing in a heavily contaminated soil. • Biochar could significantly decrease bioavailability of heavy metals (Cd, Cr, Ni, Cu, Zn) for plants. • Effects were not augmented by the addition of AMF although the production of glomalin is promoted by biochars. • AMF had not reduced bioavailability of PTEs, no significant interaction between biochar and AMF inoculation was observed. - Biochar could significantly decrease bioavailability of heavy metals (Cd, Cr, Ni, Cu, Zn) for plants, but AMF had little such effects, biochar and AMF interaction is not valid.

  1. Role of the GRAS transcription factor ATA/RAM1 in the transcriptional reprogramming of arbuscular mycorrhiza in Petunia hybrida.

    Science.gov (United States)

    Rich, Mélanie K; Courty, Pierre-Emmanuel; Roux, Christophe; Reinhardt, Didier

    2017-08-08

    Development of arbuscular mycorrhiza (AM) requires a fundamental reprogramming of root cells for symbiosis. This involves the induction of hundreds of genes in the host. A recently identified GRAS-type transcription factor in Petunia hybrida, ATA/RAM1, is required for the induction of host genes during AM, and for morphogenesis of the fungal endosymbiont. To better understand the role of RAM1 in symbiosis, we set out to identify all genes that depend on activation by RAM1 in mycorrhizal roots. We have carried out a transcript profiling experiment by RNAseq of mycorrhizal plants vs. non-mycorrhizal controls in wild type and ram1 mutants. The results show that the expression of early genes required for AM, such as the strigolactone biosynthetic genes and the common symbiosis signalling genes, is independent of RAM1. In contrast, genes that are involved at later stages of symbiosis, for example for nutrient exchange in cortex cells, require RAM1 for induction. RAM1 itself is highly induced in mycorrhizal roots together with many other transcription factors, in particular GRAS proteins. Since RAM1 has previously been shown to be directly activated by the common symbiosis signalling pathway through CYCLOPS, we conclude that it acts as an early transcriptional switch that induces many AM-related genes, among them genes that are essential for the development of arbuscules, such as STR, STR2, RAM2, and PT4, besides hundreds of additional RAM1-dependent genes the role of which in symbiosis remains to be explored. Taken together, these results indicate that the defect in the morphogenesis of the fungal arbuscules in ram1 mutants may be an indirect consequence of functional defects in the host, which interfere with nutrient exchange and possibly other functions on which the fungus depends.

  2. 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.

  3. 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...... and top of tubes, and of cocci with a diameter of 0.55-0.78 mum in the bulk soil in the center of tubes, were significantly reduced by VAM fungi. The extremely high bacterial biomass (1-7 mg C g-1 dry weight soil) was significant reduced by mycorrhizal colonization on root segments and in bulk soil...... biomass, and changed the spatial pattern of bacterial growth compared to non-mycorrhizal cucumbers. The [H-3]-thymidine incorporation was significantly higher on root tips in the top of tubes, and on root segments and bulk soil in the center of tubes on non-mycorrhizal plants compared to mycorrhizal...

  4. Gibberellin–Abscisic Acid Balances during Arbuscular Mycorrhiza Formation in Tomato

    Science.gov (United States)

    Martín-Rodríguez, José A.; Huertas, Raúl; Ho-Plágaro, Tania; Ocampo, Juan A.; Turečková, Veronika; Tarkowská, Danuše; Ludwig-Müller, Jutta; García-Garrido, José M.

    2016-01-01

    Plant hormones have become appropriate candidates for driving functional plant mycorrhization programs, including the processes that regulate the formation of arbuscules in arbuscular mycorrhizal (AM) symbiosis. Here, we examine the role played by ABA/GA interactions regulating the formation of AM in tomato. We report differences in ABA and GA metabolism between control and mycorrhizal roots. Active synthesis and catabolism of ABA occur in AM roots. GAs level increases as a consequence of a symbiosis-induced mechanism that requires functional arbuscules which in turn is dependent on a functional ABA pathway. A negative interaction in their metabolism has been demonstrated. ABA attenuates GA-biosynthetic and increases GA-catabolic gene expression leading to a reduction in bioactive GAs. Vice versa, GA activated ABA catabolism mainly in mycorrhizal roots. The negative impact of GA3 on arbuscule abundance in wild-type plants is partially offset by treatment with ABA and the application of a GA biosynthesis inhibitor rescued the arbuscule abundance in the ABA-deficient sitiens mutant. These findings, coupled with the evidence that ABA application leads to reduce bioactive GA1, support the hypothesis that ABA could act modifying bioactive GA level to regulate AM. Taken together, our results suggest that these hormones perform essential functions and antagonize each other by oppositely regulating AM formation in tomato roots. PMID:27602046

  5. Competitive interactions are mediated in a sex-specific manner by arbuscular mycorrhiza in Antennaria dioica.

    Science.gov (United States)

    Varga, S; Vega-Frutis, R; Kytöviita, M-M

    2017-03-01

    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 dioica were examined in a greenhouse experiment. Females and males were grown in the following competitive settings: (i) without competition, (ii) with intrasexual competition, (iii) with intersexual competition, and (iv) with interspecific competition by Hieracium pilosella - a plant with similar characteristics to A. dioica. Half of the pots were grown with Claroideoglomus claroideum, an AM fungus isolated from the same habitat as the plant material. We evaluated plant survival, growth, flowering phenology, and production of AM fungal structures. Plant survival was unaffected by competition or AM fungi. Competition and the presence of AM fungi reduced plant biomass. However, the sexes responded differently to the interaction between fungal and competition treatments. Both intra- and interspecific competition results were sex-specific, and in general, female performance was reduced by AM colonization. Plant competition or sex did not affect the intraradical structures, extraradical hyphae, or spore production of the AM fungus. These findings suggest that plant sexual differences affect fundamental processes such as competitive ability and symbiotic relationships with AM fungi. © 2016 German Botanical Society and The Royal Botanical Society of the Netherlands.

  6. 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.

  7. 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.

  8. 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%.

  9. Effect of Arbuscular Mycorrhiza Fungi and Pseudomonas fluorescent bactria on Nutrient Uptake of Pistachio Seedling (Pistacia Vera Cv. Qazvini under Four Irrigation Regimes

    Directory of Open Access Journals (Sweden)

    A. Shool

    2015-01-01

    Full Text Available Pistachio is one of the most important products exported from the country, which due to the low rainfall, its production is faced with water deficiency in Iran. One of the strategies adopted to deal with water deficiency and drought stress in recent years is the use of mycorrhizal fungi and phosphate solubilizing bacteria. Therefore, to study the effect of co-inoculation of arbuscular mycorrhizal fungus Glomus mosseae and Pseudomonas fluorescens P52 strain bacteria on nutrient uptake of pistachio seedling (Pistacia vera cv. Qazvini under drought stress, a greenhouse experiment was conducted using four levels of drought stress (%100 Field capacity (FC as control and 75, 50 and 25 %FC and four levels of biofertilizer (plant without mycorrhizae and bacteria as control, mycorrhizae alone (100 gr of mycorrhizal inoculum in every pot, bacteria alone (two ml of the bacterial suspension in every pot and mycorrhizae and bacteria combination (100 gr of mycorrhizal inoculum and two ml of the bacterial suspension in every pot in a completely randomized design as factorial with four replications. The experiment was carried out between the years of 2010 to 2011 on 3-months old seedlings with three seedlings per pot. In this experiment, bacteria inoculation in different levels of drought had no significant effect on root colonization by mycorrhizae, but regardless of bacterial treatment, an increase in drought intensity had a promotive effect on root colonization. The amount of phosphorus was increased using biofertilizer and in many cases the greatest amount of phosphorus was obtained in mycorrhizae and mixed treatments under 25 and 50% FC. The K+ content of shoot was maximum in the mixed treatment. The greatest amount of root Ca+ was recorded under 25% FC. Drought stress caused a significant increase in micronutrients compared with control at 25% of field capacity, but was ineffective in the roots. In conclusion, the results of this study showed that in many

  10. 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

  11. Identification of arbuscular mycorrhiza (AM-responsive microRNAs in tomato

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    Ping eWu

    2016-03-01

    Full Text Available A majority of land plants can form symbiosis with arbuscular mycorrhizal (AM fungi. MicroRNAs (miRNAs have been implicated to regulate this process in legumes, but their involvement in non-legume species is largely unknown. In this study, by performing deep sequencing of sRNA libraries in tomato roots and comparing with tomato genome, a total of 700 potential miRNAs were predicted, among them, 187 are known plant miRNAs that have been previously deposited in miRBase. Unlike the profiles in other plants such as rice and Arabidopsis, a large proportion of predicted tomato miRNAs was 24 nt in length. A similar pattern was observed in the potato genome but not in tobacco, indicating a Solanum genus-specific expansion of 24-nt miRNAs. About 40% identified tomato miRNAs showed significantly altered expressions upon Rhizophagus irregularis inoculation, suggesting the potential roles of these novel miRNAs in AM symbiosis. The differential expression of five known and six novel miRNAs were further validated using qPCR analysis. Interestingly, three up-regulated known tomato miRNAs belong to a known miR171 family, a member of which has been reported in Medicago truncatula to regulate AM symbiosis. Thus, the miR171 family likely regulates AM symbiosis conservatively across different plant lineages. More than 1000 genes targeted by potential AM-responsive miRNAs were provided and their roles in AM symbiosis are worth further exploring.

  12. CERBERUS and NSP1 of Lotus japonicus are common symbiosis genes that modulate arbuscular mycorrhiza development.

    Science.gov (United States)

    Takeda, Naoya; Tsuzuki, Syusaku; Suzaki, Takuya; Parniske, Martin; Kawaguchi, Masayoshi

    2013-10-01

    Arbuscular mycorrhizal symbiosis (AMS) and root nodule symbiosis (RNS) are mutualistic plant-microbe interactions that confer nutritional benefits to both partners. Leguminous plants possess a common genetic system for intracellular symbiosis with AM fungi and with rhizobia. Here we show that CERBERUS and NSP1, which respectively encode an E3 ubiquitin ligase and a GRAS transcriptional regulator and which have previously only been implicated in RNS, are involved in AM fungal infection in Lotus japonicus. Hyphal elongation along the longitudinal axis of the root was reduced in the cerberus mutant, giving rise to a lower colonization level. Knockout of NSP1 decreased the frequency of plants colonized by AM fungi or rhizobia. CERBERUS and NSP1 showed different patterns of expression in response to infection with symbiotic microbes. A low constitutive level of CERBERUS expression was observed in the root and an increased level of NSP1 expression was detected in arbuscule-containing cells. Induction of AM marker gene was triggered in both cerberus and nsp1 mutants by infection with symbiotic microbes; however, the mutants showed a weaker induction of marker gene expression than the wild type, mirroring their lower level of colonization. The common symbiosis genes are believed to act in an early signaling pathway for recognition of symbionts and for triggering early symbiotic responses. Our quantitative analysis of symbiotic phenotypes revealed developmental defects of the novel common symbiosis mutants in both symbioses, which demonstrates that common symbiosis mechanisms also contribute to a range of functions at later or different stages of symbiont infection.

  13. 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.

  14. Arbuscular Mycorrhiza Alleviates Restrictions to Substrate Water Flow and Delays Transpiration Limitation to Stronger Drought in Tomato.

    Science.gov (United States)

    Bitterlich, Michael; Sandmann, Martin; Graefe, Jan

    2018-01-01

    Arbuscular mycorrhizal fungi (AMF) proliferate in soil pores, on the surface of soil particles and affect soil structure. Although modifications in substrate moisture retention depend on structure and could influence plant water extraction, mycorrhizal impacts on water retention and hydraulic conductivity were rarely quantified. Hence, we asked whether inoculation with AMF affects substrate water retention, water transport properties and at which drought intensity those factors become limiting for plant transpiration. Solanum lycopersicum plants were set up in the glasshouse, inoculated or not with Funneliformis mosseae , and grown for 35 days under ample water supply. After mycorrhizal establishment, we harvested three sets of plants, one before (36 days after inoculation) and the second (day 42) and third (day 47) within a sequential drying episode. Sampling cores were introduced into pots before planting. After harvest, moisture retention and substrate conductivity properties were assessed and water retention and hydraulic conductivity models were fitted. A root water uptake model was adopted in order to identify the critical substrate moisture that induces soil derived transpiration limitation. Neither substrate porosity nor saturated water contents were affected by inoculation, but both declined after substrates dried. Drying also caused a decline in pot water capacity and hydraulic conductivity. Plant available water contents under wet (pF 1.8-4.2) and dry (pF 2.5-4.2) conditions increased in mycorrhizal substrates and were conserved after drying. Substrate hydraulic conductivity was higher in mycorrhizal pots before and during drought exposure. After withholding water from pots, higher substrate drying rates and lower substrate water potentials were found in mycorrhizal substrates. Mycorrhiza neither affected leaf area nor root weight or length. Consistently with higher substrate drying rates, AMF restored the plant hydraulic status, and increased plant

  15. Preliminary studies on the relationship between Tuber melanosporum and vesicular arbuscular mycorrizhae in the "burnt-places"

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    Rosell Armengol, Alexis

    1997-12-01

    Full Text Available The vesicular-arbuscular mycorrhizal status of the herbaceous plants living inside and outside the "burnt- places" caused by Tuber melanosporum Vitt. was examined in order to determine whether the fungus may interfere with endomycorrhizal formation. When plants surviving in the burnt-out areas were compared to those in surrounding ground, a clear reduction in growth and vesicular-arbuscular mycorrhizal colonization were observed; additionally a reduction in the number of endogonaceous spores occurring in me soil was detected. These results suggest mat T. melanosporum produces substances also inhibitive to endomycorrhizal fungi.

    S'ha examinat l'estat de les micorrizes vessículo-arbusculars de les plantes herbácies que viuen dins i fora deis tofoners deguts a Tuber melanosporum Vitt., a fi de determinar si el fong interfereix en la formació endomicorrízica. Quan varen comparar-se les plantes que sobrevivien als tofoners amb les del terreny del voltant, es va observar una clara reducció en llur creixement i en la micorrizació vessículo-arbuscular; i, a més, es va detectar una reducció notable en el nombre d'espores endogàmiques presents al sòl. Tot això suggereix que T. melanosporum produeix substancies inhibents també respecte als fongs endomicorrízics.

  16. 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

    Transport of N by hyphae of a vesicular-arbuscular mycorrhizal fungus was studied under controlled experimental conditions. The N source was applied to the soil as (NH4+)-N-15 or (NH3-)N-15. Cucumis sativus was grown for 25 days, either alone or in symbiosis with Glomus intraradices, in containers...... 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...... compartment at 7 and 12 days after labelling, and the concentration of mineral N in the samples was measured from 2 M KCl extracts. Mycorrhizal colonization did not affect plant dry weight. The recovery of N-15 in mycorrhizal plants was 38 or 40%, respectively, when (NH4+)-N-15 or (NO3-)-N-15 was applied...

  17. Existing of Vesicular Arbuscular Mycorrhizal on The Corn Field Subjected by Long-term Organic and Inorganic Fertilizers

    Directory of Open Access Journals (Sweden)

    Sri Yusnaini

    2009-09-01

    Full Text Available The existing of vesicular arbuscular mycorrhizal fungi was determined in continuously cropping systems which had applied by organic and/or inorganic fertilizers for a long term (4 years application of corn and upland rice rotation. The experiment was established at Taman Bogo, Probolinggo sub-district, East Lampung district. The experiment were: control (without fertilizer, 20 Mg ha-1 chicken manure (CK, 20 Mg ha-1 green manure Glyricidium sp. (GM, 100 % inorganic fertilizers (IF (urea 300 kg ha-1, SP 36 200 kg ha-1, and KCl 100 kg ha-1, 50% CK + 50% IF, 50% GM + 50% IF, 75% CK + 25% IF, and 75% GM + 25% IF. Soil samples were taken at the first corn growing season (2001 and the eight corn growing season (2004. VAM fungi spores were examined by wet sieving methods. The results showed that application of chicken manure or its combination with inorganic fertilizers had higher VAM fungi spore. The dominant species of VAM fungi at all treatment was Glomus constrictum.

  18. Establishment of vesicular-arbuscular mycorrhizal fungi and other microorganisms on a beach replenishment site in Florida.

    Science.gov (United States)

    Sylvia, D M; Will, M E

    1988-02-01

    Beach replenishment is a widely used method of controlling coastal erosion. To reduce erosional losses from wind, beach grasses are often planted on the replenishment sands. However, there is little information on the microbial populations in this material that may affect plant establishment and growth. The objectives of this research were to document changes in the populations of vesicular-arbuscular mycorrhizal (VAM) fungi and other soil microorganisms in replenishment materials and to determine whether roots of transplanted beach grasses become colonized by beneficial microbes. The study was conducted over a 2-year period on a replenishment project in northeastern Florida. Three sampling locations were established at 1-km intervals along the beach. Each location consisted of three plots: an established dune, replenishment sand planted with Uniola paniculata and Panicum sp., and replenishment sand left unplanted. Fungal and bacterial populations increased rapidly in the rhizosphere of beach grasses in the planted plots. However, no bacteria were recovered that could fix significant amounts of N(2). The VAM fungi established slowly on the transplanted grasses. Even after two growing seasons, levels of root colonization and sporulation were significantly below those found in the established dune. There was a shift in the dominant VAM fungi found in the planted zone with respect to those in the established dunes. The most abundant species recovered from the established dunes were Glomus deserticola, followed by Acaulospora scrobiculata and Scutellospora weresubiae. The VAM fungi that colonized the planted zone most rapidly were Glomus globiferum, followed by G. deserticola and Glomus aggregatum.

  19. Comparative nitrogen fixation, native arbuscular mycorrhiza formation and biomass production potentials of some grain legumes species grown in the field in the Guinea Savannah zone of Ghana

    International Nuclear Information System (INIS)

    Ahiabor, B.D.K.; Fosu, M.; Tibo, I.; Sumaila, I.

    2007-01-01

    An on-station trial was conducted in the experimental field of Savannah Agricultural Research Institute at Nyankpala in the Northern Region of Ghana to assess the nitrogen fixation, native arbuscular mycorrhizal formation and biomass production potentials of cowpea (Vigna unguiculata), devil-bean (Crotalaria retusa), Mucuna pruriens var. utilis (black and white types) and Canavalia ensiformis with maize (Dorke SR) as the reference crop using the total nitrogen difference (TND) method. Plants were fertilized with 40 kg P/ha and 30 kg K/ha at 2 weeks after planting and grown for 55 days after which they were harvested. The harvested biomass (separated into roots, stems and leaves) of each crop was oven-dried at 70 0 C for 48 h to a constant weight. Cowpea and devil-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 most heavily colonized (34%) and M. pruriens recording below 5% colonization. Apart from C. ensiformis, the test legumes derived over 50% of their total accumulated N from the atmosphere with cowpea being the most efficient (90% Ndfa). Both N and P accumulations were significantly higher in cowpea than the other legumes due to increased N concentration and dry matter accumulation, respectively. In all the legumes, there was a direct positive correlation between the extent of mycorrhiza formation, biological N fixation and total N uptake. It could, therefore, be concluded that the extensive mycorrhiza formation in cowpea and its high N 2 -fixing potential resulted in a high shoot N and P uptake leading to a comparatively better growth enhancement. Cowpea could, therefore, be the grain legume for consideration in the selection of a suitable legume pre-crop to cereals for the amelioration of the low fertility of the degraded soils of the Guinea savannah zone of Ghana, and also as

  20. Influence of Aphelenchus avenae on Vesicular-arbuscular Endomycorrhizal Growth Response in Cotton.

    Science.gov (United States)

    Hussey, R S; Roncadori, R W

    1981-01-01

    The influence of Aphelenchus avenae on the relationship between cotton (Gossypium hirsutum 'Stoneville 213') and Gigaspora margarita or Glomus etunicatus was assessed by its effect on the mycorrhizal stimulation of plant growth and microorganism reproduction. The mycophagous nematode usually did not suppress stimulation of shoot growth resulting from mycorrhizae (G. margarita) at inoculum levels of 3,000 or 6,000 nematodes per pot, but retarded root growth at 6,000 per pot. When the nematode inoculum was increased to 10, 40, or 80 thousand, G. margarita stimulation of shoot or root growth was retarded at the two higher rates. Shoot growth enhancement by G. etunicatus was suppressed by 10 thousand A. avenae but not by 40 or 80 thousand. A. avenae reproduced better when the nematode was added 3 wk after G. margarita than with simultaneous inoculations. Sporulation of both fungi was affected little by the mycophagous nematode. The high numbers of A. avenae required for an antagonistic effect probably precludes the occurrence of any significant interaction between these two organisms under field conditions.

  1. EFFECTS OF VARIOUS SOIL ENVIRONMENTAL STRESSES ON THE OCCURRENCE, DISTRIBUTION AND EFFECTIVENESS OF VA MYCORRHIZAE

    Directory of Open Access Journals (Sweden)

    A.G. KHAN

    1995-01-01

    Full Text Available The vesicular - arbuscular (VA mycorrhizal fungi are geographically ubiquitous soil inhabitants and form universal symbiotic relationship with plants from every phylum. These fungi link host plants with host soils and their biota in the mycorrhizosphere and play an important role in plant health, productivity and soil structure. Although VA mycorrhizal fungi do not show any host specificity, there is increasing evidence that various climatic and edaphic environmental factors such as land use and management practices, physical, chemical and biological properties of host soils and host plant characteristics influence their occurrence, taxonomic distribution and effectiveness. The interaction of these factors with vesicular-arbuscular mycorrhizae (VAM is poorly understood except in a few cases. It is now very clear that VA mycorrhizal associations are ecologically significant factors that require more attention than previously accorded. This paper discusses the occurrence, distribution and significance of VAM in environmentally stressed soil conditions that limit plant growth such as drought, waterlogging and salinity.

  2. Arbuscular mycorrhiza and water and nutrient supply differently impact seedling performance of dry woodland species with different acquisition strategies

    NARCIS (Netherlands)

    Emiru Birhane, E.B.; Kuyper, T.W.; Sterck, F.J.; Gebrehiwot, K.; Bongers, F.

    2015-01-01

    Background: Arbuscular mycorrhizal (AM) fungi increase seedling survival and performance through enhancement of nutrient and water uptake under stress conditions. Acacia etbaica, A. senegal and Boswellia papyrifera dominate large areas in African drylands where both moisture and nutrients are

  3. Influence of arbuscular mycorrhizae on biomass production and nitrogen fixation of berseem clover plants subjected to water stress.

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    Sergio Saia

    Full Text Available Several studies, performed mainly in pots, have shown that arbuscular mycorrhizal symbiosis can mitigate the negative effects of water stress on plant growth. No information is available about the effects of arbuscular mycorrhizal symbiosis on berseem clover growth and nitrogen (N fixation under conditions of water shortage. A field experiment was conducted in a hilly area of inner Sicily, Italy, to determine whether symbiosis with AM fungi can mitigate the detrimental effects of drought stress (which in the Mediterranean often occurs during the late period of the growing season on forage yield and symbiotic N2 fixation of berseem clover. Soil was either left under water stress (i.e., rain-fed conditions or the crop was well-watered. Mycorrhization treatments consisted of inoculation of berseem clover seeds with arbuscular mycorrhizal spores or suppression of arbuscular mycorrhizal symbiosis by means of fungicide treatments. Nitrogen biological fixation was assessed using the 15N-isotope dilution technique. Arbuscular mycorrhizal symbiosis was able to mitigate the negative effect of water stress on berseem clover grown in a typical semiarid Mediterranean environment. In fact, under water stress conditions, arbuscular mycorrhizal symbiosis resulted in increases in total biomass, N content, and N fixation, whereas no effect of crop mycorrhization was observed in the well-watered treatment.

  4. Influence of arbuscular mycorrhizae on biomass production and nitrogen fixation of berseem clover plants subjected to water stress.

    Science.gov (United States)

    Saia, Sergio; Amato, Gaetano; Frenda, Alfonso Salvatore; Giambalvo, Dario; Ruisi, Paolo

    2014-01-01

    Several studies, performed mainly in pots, have shown that arbuscular mycorrhizal symbiosis can mitigate the negative effects of water stress on plant growth. No information is available about the effects of arbuscular mycorrhizal symbiosis on berseem clover growth and nitrogen (N) fixation under conditions of water shortage. A field experiment was conducted in a hilly area of inner Sicily, Italy, to determine whether symbiosis with AM fungi can mitigate the detrimental effects of drought stress (which in the Mediterranean often occurs during the late period of the growing season) on forage yield and symbiotic N2 fixation of berseem clover. Soil was either left under water stress (i.e., rain-fed conditions) or the crop was well-watered. Mycorrhization treatments consisted of inoculation of berseem clover seeds with arbuscular mycorrhizal spores or suppression of arbuscular mycorrhizal symbiosis by means of fungicide treatments. Nitrogen biological fixation was assessed using the 15N-isotope dilution technique. Arbuscular mycorrhizal symbiosis was able to mitigate the negative effect of water stress on berseem clover grown in a typical semiarid Mediterranean environment. In fact, under water stress conditions, arbuscular mycorrhizal symbiosis resulted in increases in total biomass, N content, and N fixation, whereas no effect of crop mycorrhization was observed in the well-watered treatment.

  5. Effects of phosphorus availability and vesicular-arbuscular mycorrhizas on the carbon budget of common bean (Phaseolus vulgaris)

    NARCIS (Netherlands)

    Nielsen, K.F.; Bouma, T.J.; Lynch, J.P.; Eissenstat, D.M.

    1998-01-01

    Low phosphorus availability is often a primary constraint to plant productivity in native soils. Here we test the hypothesis that root carbon costs are a primary limitation to plant growth in low P soils by assessing the effect of P availability and mycorrhizal infection on whole plant C budgets in

  6. 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.

  7. 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

    The possible role of arbuscular mycorrhizal fungi in the transfer of nitrogen and phosphorus from Pueraria phaseoloides (donor) to Hevea brasiliensis (receiver) was examined. P. phaseoloides is used as a cover crop in rubber tree (H. brasiliensis) plantations. Roots of donor and receiver plants...

  8. Mutualistic functioning of indigenous arbuscular mycorrhizae in spring barley and winter wheat after cessation of long-term phosphate fertilization

    NARCIS (Netherlands)

    Dekkers, T.B.M.; Werff, van der P.A.

    2001-01-01

    The influence of 23 years of phosphorus (P) application at three annual rates of 0, 17.5 and 52.5 kg ha-1 on arbuscular mycorrhizal (AM) fungal colonization was studied 10 years after the fertilization treatment ended. The annual application of 52.5 kg ha-1 was about twice the annual crop P

  9. [Effect of vesicular-arbuscular mycorrhizal fungi on growth, nutrient uptake and synthesis of volatile oil in Schizonepeta tenuifolia briq].

    Science.gov (United States)

    Wei, G; Wang, H

    1991-03-01

    Inoculating Schizonepeta tenuifolia with VA mycorrhizal fungi can significantly improve the plant growth and uptake of P and S, and influence the absorption of K, Na, Fe, Mo, Mn, Zn, Co, Ba, Ni and Pb. It is interesting to note that VA mycorrhiza can also increase the synthesis of volatile oil in the shoots of S. tenuifolia. The efficiency of VA mycorrhiza varies with the fungal species.

  10. 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

  11. Evaluation of Two Biochemical Markers for Salt Stress in Three Pistachio Rootstocks Inoculated with Arbuscular Mycorrhiza (Glomus mosseae)

    OpenAIRE

    Shamshiri M.H.; Fattahi. M.

    2014-01-01

    The possible involvement of the methylglyoxal and proline accumulation in leaves and roots of three pistachio rootstocks, cv. Sarakha, Abareqi and Bane baghi, pre-inoculated with arbuscular mycorrhizal fungus ( Glomus mosseae ) in response to salt stress was studied during a greenhouse experiment in 2013. Six months old pistachio seedlings were exposed to four salinity levels of irrigation water (EC of 0.5 as control, 5, 10 and 15 dS m -1) for 70 days. Methylglyoxal and proline of the roots a...

  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. 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

  14. A key role for arbuscular mycorrhiza in plant acquisition of P from sewage sludge recycled to soil

    DEFF Research Database (Denmark)

    Mackay, Jessica E.; Cavagnaro, Timothy R.; Müller-Stöver, Dorette Sophie

    2017-01-01

    Dried and incinerated sewage sludge (SS) have the potential to be used as phosphorus (P) fertilisers. Arbuscular mycorrhizal fungi (AMF) contribute to plant P uptake; however, their role in P uptake from SS has yet to be fully explored. A compartmented pot system with an isotope pool dilution...... approach was used to investigate wheat (Triticum aestivum L.) P uptake from soluble P, dried SS and incinerated SS, via roots and/or AMF hyphae. Wheat was sown into an inner compartment containing a 33P label with/without AMF (Rhizophagus irregularis) inoculum. An outer soil compartment contained the P...... access dried SS than when only roots could access dried SS. We discuss the results in terms of availability of P to roots and hyphae. We conclude that AMF play an important role in wheat P acquisition from dried SS and therefore can assist in the recycling of P in waste....

  15. Arbuscular mycorrhiza improve growth, nitrogen uptake, and nitrogen use efficiency in wheat grown under elevated CO2

    DEFF Research Database (Denmark)

    Zhu, Xiancan; Song, Fengbin; Liu, Shengqun

    2016-01-01

    Effects of the arbuscular mycorrhizal (AM) fungus Rhizophagus irregularis on plant growth, carbon (C) and nitrogen (N) accumulation, and partitioning was investigated in Triticum aestivum L. plants grown under elevated CO2 in a pot experiment. Wheat plants inoculated or not inoculated with the AM...... and higher plant biomass than the non-AM plants. CO2 elevation did not affect C and N partitioning in plant organs, while AM symbiosis increased C and N allocation into the roots. In addition, plant C and N accumulation, (15)N recovery rate, and N use efficiency (NUE) were significantly higher in AM plants...... than in non-AM controls under CO2 enrichment. It is concluded that AM symbiosis favors C and N partitioning in roots, increases C accumulation and N uptake, and leads to greater NUE in wheat plants grown at elevated CO2....

  16. Influência da colonização micorrízica arbuscular sobre a nutrição do quiabeiro Influence of arbuscular mycorrhiza fungi on the nutrition of okra plant

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    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

  17. Effect of Arbuscular Mycorrhizae on zinc nutrition of maize grow in calcareous soil amended with different phosphorus sources

    International Nuclear Information System (INIS)

    Aly, S.S.M.; EL-Ghandour, I. A.

    2001-01-01

    Arbuscular mycorrhizal fungi (AMF) are known to improve P nutrition of plants. The information of AMF effects on corn Zn nutrition under P fertilization in calcareous soil is limited. A greenhouse experiment was carried out using calcareous soil and two P-sources i.e single superphosphate and rock phosphate (with full and one third of recommended dose). to evaluate the ability of AMF on improving Zn nutrition in maize plants. Labelled 65 ZnSo 4 was added at rates of 0.10 and 20 mg Zn Kg -1 soil. Zinc uptake and dry mater of corn shoots were improved as a result of AMF inoculation. The maximum improvement was recorded with super-P fertilizer in combination with 10 or 20 mg Zn Kg -1 soil for non-inoculated and AMF inoculated plants. respectively. The amount of Zn in non-inoculated and AMF inoculated plants. respectively. The amount of ZnSo 4 utilized plant derived from fertilizer.(Zndff) and the percent of ZnSo 4 utilization by corn plants were increased when ZnSo 4 was added at rate of 10 mg Zn Kg -1 soil in the presence of super-P fertilizer. Inoculated plants with AMF had higher Zndff content and U% than non-inoculated ones and the greater Zndff and superphosphate fertilizer. It could be concluded that. AMF is useful method utilization by corn plants grown in calcareous soil

  18. Evaluation of Two Biochemical Markers for Salt Stress in Three Pistachio Rootstocks Inoculated with Arbuscular Mycorrhiza (Glomus mosseae

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    Shamshiri M.H.

    2014-03-01

    Full Text Available The possible involvement of the methylglyoxal and proline accumulation in leaves and roots of three pistachio rootstocks, cv. Sarakha, Abareqi and Bane baghi, pre-inoculated with arbuscular mycorrhizal fungus (Glomus mosseae in response to salt stress was studied during a greenhouse experiment in 2013. Six months old pistachio seedlings were exposed to four salinity levels of irrigation water (EC of 0.5 as control, 5, 10 and 15 dS m-1 for 70 days. Methylglyoxal and proline of the roots and leaves were increased by increasing salt stress. The highest concentrations of proline in leaves and roots were recorded in Abareqi rootstock while the lowest concentration was observed in Sarakhs. In general, a negative relationship was obtained between proline and methylglyoxal concentrations in both tissues especially at two highest levels of salinity. A very strong relationship between salinity and measured biochemical markers were found. The level of both biomarkers were reduced in both tissues and in all rootstocks as the effect of mycorrhizal symbiosis. Root colonization percentage was declined as the effect of salinity in Abareqi and Bane baghi and not in Sarakhs.

  19. Arbuscular mycorrhiza improve growth, nitrogen uptake, and nitrogen use efficiency in wheat grown under elevated CO2.

    Science.gov (United States)

    Zhu, Xiancan; Song, Fengbin; Liu, Shengqun; Liu, Fulai

    2016-02-01

    Effects of the arbuscular mycorrhizal (AM) fungus Rhizophagus irregularis on plant growth, carbon (C) and nitrogen (N) accumulation, and partitioning was investigated in Triticum aestivum L. plants grown under elevated CO2 in a pot experiment. Wheat plants inoculated or not inoculated with the AM fungus were grown in two glasshouse cells with different CO2 concentrations (400 and 700 ppm) for 10 weeks. A (15)N isotope labeling technique was used to trace plant N uptake. Results showed that elevated CO2 increased AM fungal colonization. Under CO2 elevation, AM plants had higher C concentration and higher plant biomass than the non-AM plants. CO2 elevation did not affect C and N partitioning in plant organs, while AM symbiosis increased C and N allocation into the roots. In addition, plant C and N accumulation, (15)N recovery rate, and N use efficiency (NUE) were significantly higher in AM plants than in non-AM controls under CO2 enrichment. It is concluded that AM symbiosis favors C and N partitioning in roots, increases C accumulation and N uptake, and leads to greater NUE in wheat plants grown at elevated CO2.

  20. Plant growth responses to elevated atmospheric CO2 are increased by phosphorus sufficiency but not by arbuscular mycorrhizas

    DEFF Research Database (Denmark)

    Jakobsen, Iver; Smith, Sally E.; Smith, F. Andrew

    2016-01-01

    Capturing the full growth potential in crops under future elevated CO2 (eCO2) concentrations would be facilitated by improved understanding of eCO2 effects on uptake and use of mineral nutrients. This study investigates interactions of eCO2, soil phosphorus (P), and arbuscular mycorrhizal (AM......) symbiosis in Medicago truncatula and Brachypodium distachyon grown under the same conditions. The focus was on eCO2 effects on vegetative growth, efficiency in acquisition and use of P, and expression of phosphate transporter (PT) genes. Growth responses to eCO2 were positive at P sufficiency, but under low......-P conditions they ranged from non-significant in M. truncatula to highly significant in B. distachyon. Growth of M. truncatula was increased by AM at low P conditions at both CO2 levels and eCO2×AM interactions were sparse. Elevated CO2 had small effects on P acquisition, but enhanced conversion of tissue P...

  1. Plant growth responses to elevated atmospheric CO2 are increased by phosphorus sufficiency but not by arbuscular mycorrhizas.

    Science.gov (United States)

    Jakobsen, Iver; Smith, Sally E; Smith, F Andrew; Watts-Williams, Stephanie J; Clausen, Signe S; Grønlund, Mette

    2016-11-01

    Capturing the full growth potential in crops under future elevated CO 2 (eCO 2 ) concentrations would be facilitated by improved understanding of eCO 2 effects on uptake and use of mineral nutrients. This study investigates interactions of eCO 2 , soil phosphorus (P), and arbuscular mycorrhizal (AM) symbiosis in Medicago truncatula and Brachypodium distachyon grown under the same conditions. The focus was on eCO 2 effects on vegetative growth, efficiency in acquisition and use of P, and expression of phosphate transporter (PT) genes. Growth responses to eCO 2 were positive at P sufficiency, but under low-P conditions they ranged from non-significant in M. truncatula to highly significant in B. distachyon Growth of M. truncatula was increased by AM at low P conditions at both CO 2 levels and eCO 2 ×AM interactions were sparse. Elevated CO 2 had small effects on P acquisition, but enhanced conversion of tissue P into biomass. Expression of PT genes was influenced by eCO 2 , but effects were inconsistent across genes and species. The ability of eCO 2 to partly mitigate P limitation-induced growth reductions in B. distachyon was associated with enhanced P use efficiency, and requirements for P fertilizers may not increase in such species in future CO 2 -rich climates. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  2. Time of Stablishment of Pastures and Their Relationship with Arbuscular Mycorrhiza in Hilly Terrain and Fertile Valley

    Directory of Open Access Journals (Sweden)

    Raúl Hernando Posada Almanza

    2006-07-01

    Full Text Available The subject of this research was to evaluate the effect of the time of establishment (0-5 years, 5-10 years, and more than 10 years. of pastures of Brachiaria sp. over theArbuscular Mycorrhizal Fungal populations (AMF: genus and spore distribution, length of extramatrical mycelia, root colonizations by AMF and septate fungi; the pastures resulting from fragmentation of the tropical rainforest with valley and hilly landscapes at Florencia, Caquetá, Colombia. Whichever the age of pasture, the genera Glomus and Acaulospora predominate; the change of coverage require more than ten years for different species of MAF to recolonize, adapt and diversify. In hilly terrain, the Brachiaria sp-MAF relationship decrease with time, specially after ten years of establishment; in valley landscapes the relationship is medium and homogeneous (21- 50%, while the root colonization by septate fungi increased, showing possibly a competitive mechanism by root space or a cooperative activity. Finally, the extramatrical mycelia and spores in any landscape had a variable behavior (increase, decrease or stability with time.

  3. Gate crashing arbuscular mycorrhizas: in vivo imaging shows the extensive colonization of both symbionts by Trichoderma atroviride.

    Science.gov (United States)

    Lace, Beatrice; Genre, Andrea; Woo, Sheridan; Faccio, Antonella; Lorito, Matteo; Bonfante, Paola

    2015-02-01

    Plant growth-promoting fungi include strains of Trichoderma species that are used in biocontrol, and arbuscular mycorrhizal (AM) fungi, that enhance plant nutrition and stress resistance. The concurrent interaction of plants with these two groups of fungi affects crop performance but has only been occasionally studied so far. Using in vivo imaging of green fluorescent protein-tagged lines, we investigated the cellular interactions occurring between Trichoderma atroviride PKI1, Medicago truncatula and two Gigaspora species under in vitro culture conditions. Trichoderma atroviride did not activate symbiotic-like responses in the plant cells, such as nuclear calcium spiking or cytoplasmic aggregations at hyphal contact sites. Furthermore, T. atroviride parasitized G. gigantea and G. margarita hyphae through localized wall breaking and degradation - although this was not associated with significant chitin lysis nor the upregulation of two major chitinase genes. Trichoderma atroviride colonized broad areas of the root epidermis, in association with localized cell death. The infection of both symbionts was also observed when T. atroviride was applied to a pre-established AM symbiosis. We conclude that - although this triple interaction is known to improve plant growth in agricultural environments - in vitro culture demonstrate a particularly aggressive mycoparasitic and plant-colonizing behaviour of a biocontrol strain of Trichoderma. © 2014 Society for Applied Microbiology and John Wiley & Sons Ltd.

  4. Influence of fertilization, season, and forage species in presence of arbuscular mycorrhizae in a degraded Andisoil of Colombia

    Directory of Open Access Journals (Sweden)

    Otero Joel Tupac

    2011-03-01

    Full Text Available Para determinar la influencia de la fertilización, época, y especies forrajeras en la producción de micorrizas arbusculares  se realizó un experimento  con una graminea C4, (Brachiaria dictyoneura, dos leguminosas forrajeras C3  (Arachis pintoi y Centrosema macrocarpum  y la vegetación nativa; cultivadas en dos sistemas de siembra (monocultivo y asociación, dos niveles de fertilización (alto y bajo y cuatro edades de cosecha. Se uso un diseño de parcelas sub-sub divididas, en el cual la parcela principal fue la especie, los niveles de  fertilización como subparcelas y la edad de rebrote como la sub-sub parcela. El número de esporas de hongos micorrizicos en el suelo y el porcentaje de infección en las raices se incrementó con la edad y varió con la especie y la época del muestreo (seca o húmeda. Se encontraron diferencias en la capacidad para formar simbiosis micorrízica entre las especies de gramíneas y leguminosas bajo condiciones de campo.

  5. Effect of inoculation with arbuscular mycorrhizas on rooting, weaning and subsequent growth of micropropagated Malus (L. Moench

    Directory of Open Access Journals (Sweden)

    Marjatta Uosukainen

    1994-05-01

    Full Text Available The importance of different rooting methods and the effects of arbuscular mycorrhizal (AMF inoculation on the rooting rate, weaning survival and subsequent growth of microcuttings of Malus rootstock YP and the Finnish crab apple cultivars Hanna and Marjatta were studied in four experiments conducted at the Laukaa Research and Elite Plant Unit, Finland. Sucrose in the in vitro rooting medium gave the best support to weaning survival in comparision with glucose and fructose. Directly rooted microcuttings had a higher survival rate than in vitro rooted microcuttings. AMF inoculation did not improve the rooting rate in direct rooting. However, the Glomus hoi strain V98 caused severe rotting of microcuttings and thus lowered the rooting rate of cv. Hanna, AMF inoculation increased the mean shoot height of established plants, particularly inoculation with G. hoi V98, G. claroideum V43a or G. fistulosum V128. This effect, however, varied considerably in different host-fungus combinations. Some AMF strains, e.g. G. hoi V1O4, caused strong growth retardation. After the rooting and weaning stage, many uninoculated plants lapsed into arrest of growth. This phenomenon was less frequent in AMF inoculated plants. Optimal timing of AMF inoculation and nutritional level of rooting and weaning substrate are discussed.

  6. Inoculation with arbuscular mycorrhizae does not improve 137Cs uptake in crops grown in the Chernobyl region.

    Science.gov (United States)

    Vinichuk, M; Mårtensson, A; Rosén, K

    2013-12-01

    Methods for cleaning up radioactive contaminated soils are urgently needed. In this study we investigated whether the use of arbuscular mycorrhizal (AM) fungi can improve (137)Cs uptake by crops. Barley, cucumber, perennial ryegrass, and sunflower were inoculated with AM fungi and grown in low-level radionuclide contaminated soils in a field experiment 70 km southwest of Chernobyl, Ukraine, during two successive years (2009-2010). Roots of barley, cucumber and sunflower plants were slightly or moderately infected with AM fungus and root infection frequency was negatively or non-correlated with (137)Cs uptake by plants. Roots of ryegrass were moderately infected with AM fungus and infection frequency was moderately correlated with (137)Cs uptake by ryegrass. The application of AM fungi to soil in situ did not enhance radionuclide plant uptake or biomass. The responsiveness of host plants and AM fungus combination to (137)Cs uptake varied depending on the soil, although mycorrhization of soil in the field was conditional and did not facilitate the uptake of radiocesium. The total amount of (137)Cs uptake by plants growing on inoculated soil was equal to amounts in plant cultivated on non-inoculated soil. Thus, the use of AM fungi in situ for bioremediation of soil contaminated with a low concentration of (137)Cs could not be recommended. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Host-specific effects of soil microbial filtrates prevail over those of arbuscular mycorrhizae in a fragmented landscape.

    Science.gov (United States)

    Pizano, Camila; Mangan, Scott A; Graham, James H; Kitajima, Kaoru

    2017-09-01

    Plant-soil interactions have been shown to determine plant community composition in a wide range of environments. However, how plants distinctly interact with beneficial and detrimental organisms across mosaic landscapes containing fragmented habitats is still poorly understood. We experimentally tested feedback responses between plants and soil microbial communities from adjacent habitats across a disturbance gradient within a human-modified tropical montane landscape. In a greenhouse experiment, two components of soil microbial communities were amplified; arbuscular mycorrhizal fungi (AMF) and a filtrate excluding AMF spores from the soils of pastures (high disturbance), coffee plantations (intermediate disturbance), and forest fragments (low disturbance), using potted seedlings of 11 plant species common in these habitats (pasture grass, coffee, and nine native species). We then examined their effects on growth of these same 11 host species with reciprocal habitat inoculation. Most plant species received a similar benefit from AMF, but differed in their response to the filtrates from the three habitats. Soil filtrate from pastures had a net negative effect on plant growth, while filtrates from coffee plantations and forests had a net positive effect on plant growth. Pasture grass, coffee, and five pioneer tree species performed better with the filtrate from "away" (where these species rarely occur) compared to "home" (where these species typically occur) habitat soils, while four shade-tolerant tree species grew similarly with filtrates from different habitats. These results suggest that pastures accumulate species-specific soil enemies, while coffee plantations and forests accumulate beneficial soil microbes that benefit pioneer native plants and coffee, respectively. Thus, compared to AMF, soil filtrates exerted stronger habitat and host-specific effects on plants, being more important mediators of plant-soil feedbacks across contrasting habitats. © 2017 by

  8. Inoculation with arbuscular mycorrhizae does not improve 137Cs uptake in crops grown in the Chernobyl region

    International Nuclear Information System (INIS)

    Vinichuk, M.; Mårtensson, A.; Rosén, K.

    2013-01-01

    Methods for cleaning up radioactive contaminated soils are urgently needed. In this study we investigated whether the use of arbuscular mycorrhizal (AM) fungi can improve 137 Cs uptake by crops. Barley, cucumber, perennial ryegrass, and sunflower were inoculated with AM fungi and grown in low-level radionuclide contaminated soils in a field experiment 70 km southwest of Chernobyl, Ukraine, during two successive years (2009–2010). Roots of barley, cucumber and sunflower plants were slightly or moderately infected with AM fungus and root infection frequency was negatively or non-correlated with 137 Cs uptake by plants. Roots of ryegrass were moderately infected with AM fungus and infection frequency was moderately correlated with 137 Cs uptake by ryegrass. The application of AM fungi to soil in situ did not enhance radionuclide plant uptake or biomass. The responsiveness of host plants and AM fungus combination to 137 Cs uptake varied depending on the soil, although mycorrhization of soil in the field was conditional and did not facilitate the uptake of radiocesium. The total amount of 137 Cs uptake by plants growing on inoculated soil was equal to amounts in plant cultivated on non-inoculated soil. Thus, the use of AM fungi in situ for bioremediation of soil contaminated with a low concentration of 137 Cs could not be recommended. -- Highlights: • Effect of mycorrhization on 137 Cs uptake by crops was studied in a field experiment. • AM fungi did not enhance radionuclide plant uptake or biomass. • Plants growing on inoculated and non-inoculated soil accumulate 137 Cs equally

  9. RiArsB and RiMT-11: Two novel genes induced by arsenate in arbuscular mycorrhiza.

    Science.gov (United States)

    Maldonado-Mendoza, Ignacio E; Harrison, Maria J

    Plants associated with arbuscular mycorrhizal fungi (AMF) increase their tolerance to arsenic-polluted soils. This study aims to investigate the genes involved in the AMF molecular response to arsenic pollution. Genes encoding proteins involved in arsenic metabolism were identified and their expression assessed by PCR or RT-qPCR. The As-inducible gene GiArsA (R. irregularis ABC ATPase component of the ArsAB arsenite efflux pump) and two new genes, an arsenate/arsenite permease component of ArsAB (RiArsB) and a methyltransferase type 11 (RiMT-11) were induced when arsenate was added to two-compartment in vitro monoxenic cultures of R. irregularis-transformed carrot roots. RiArsB and RiMT-11 expression in extraradical hyphae in response to arsenate displayed maximum induction 4-6 h after addition of 350 μM arsenate. Their expression was also detected in colonized root tissues grown in pots, or in the root-fungus compartment of two-compartment in vitro systems. We used a Medicago truncatula double mutant (mtpt4/mtpt8) to demonstrate that RiMT-11 and RiArsB transcripts accumulate in response to the addition of arsenate but not in response to phosphate. These results suggest that these genes respond to arsenate addition regardless of non-functional Pi symbiotic transport, and that RiMT-11 may be involved in arsenate detoxification by methylation in AMF-colonized tissues. Copyright © 2017 British Mycological Society. All rights reserved.

  10. Arbuscular mycorrhizae alleviate negative effects of zinc oxide nanoparticle and zinc accumulation in maize plants--A soil microcosm experiment.

    Science.gov (United States)

    Wang, Fayuan; Liu, Xueqin; Shi, Zhaoyong; Tong, Ruijian; Adams, Catharine A; Shi, Xiaojun

    2016-03-01

    ZnO nanoparticles (NPs) are considered an emerging contaminant when in high concentration, and their effects on crops and soil microorganisms pose new concerns and challenges. Arbuscular mycorrhizal (AM) fungi (AMF) form mutualistic symbioses with most vascular plants, and putatively contribute to reducing nanotoxicity in plants. Here, we studied the interactions between ZnO NPs and maize plants inoculated with or without AMF in ZnO NPs-spiked soil. ZnO NPs had no significant adverse effects at 400 mg/kg, but inhibited both maize growth and AM colonization at concentrations at and above 800 mg/kg. Sufficient addition of ZnO NPs decreased plant mineral nutrient acquisition, photosynthetic pigment concentrations, and root activity. Furthermore, ZnO NPs caused Zn concentrations in plants to increase in a dose-dependent pattern. As the ZnO NPs dose increased, we also found a positive correlation with soil diethylenetriaminepentaacetic acid (DTPA)-extractable Zn. However, AM inoculation significantly alleviated the negative effects induced by ZnO NPs: inoculated-plants experienced increased growth, nutrient uptake, photosynthetic pigment content, and SOD activity in leaves. Mycorrhizal plants also exhibited decreased ROS accumulation, Zn concentrations and bioconcentration factor (BCF), and lower soil DTPA-extractable Zn concentrations at high ZnO NPs doses. Our results demonstrate that, at high contamination levels, ZnO NPs cause toxicity to AM symbiosis, but AMF help alleviate ZnO NPs-induced phytotoxicity by decreasing Zn bioavailability and accumulation, Zn partitioning to shoots, and ROS production, and by increasing mineral nutrients and antioxidant capacity. AMF may play beneficial roles in alleviating the negative effects and environmental risks posed by ZnO NPs in agroecosystems. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Induction of fungal disease resistance in Vicia faba by dual inoculation with Rhizobium leguminosarum and vesicular-arbuscular mycorrhizal fungi.

    Science.gov (United States)

    Rabie, G H

    1998-01-01

    Infection of Vicia faba with Bothytis fabae causes significant decreases in growth vigour, total nitrogen content, number of nodules and nutrient accumulation. Na-uptake and phenolics concentration increased compared to that of noninfected plants. In contrast, dual inoculation of Rhizobium and VA mycorrhizae increased all above parameters suggesting a distinct improvement of the plants. The results also revealed that an inverse correlation may exist between phenolic, calcium, magnesium and zinc concentrations in mycorrhizal plant tissues grown in presence of rhizobial bacteria and the disease severity. From these findings we conclude a possible role of both VA mycorrhizal fungi and rhizobial bacteria in the decrease of susceptibility of plants.

  12. Effectiveness of native arbuscular mycorrhiza on the growth of four tree forest species from the Santa Marta Mountain, Veracruz (Mexico)

    Energy Technology Data Exchange (ETDEWEB)

    Retama-Ortiz, Y.; Ávila-Bello, C.H.; Alarcón, A.; Ferrera-Cerrato, R.

    2017-11-01

    Aim of the study: The aim of this work was to isolate consortia of arbuscular mycorrhizal fungi (AMF) associated to Liquidambar styraciflua in soils of the Santa Marta Mountain in Veracruz, and to select highly effective mycorrhizal consortia on promoting the growth of four tree forest species with economic and ecological importance. Area of study: Santa Marta Mountain, inside the buffer area of the Los Tuxtlas Biological Reserve in Veracruz (México). Materials and methods: Ten composite samples of rhizosphere soil were collected from L. styraciflua trees of 13-15 cm DBH (diameter at breast height). Roots were fixed in FAA solution to determine the mycorrhizal colonization percentage, the abundance of morphospecies, and its effectiveness in promoting the growth of L. styraciflua, Terminalia amazonia, Cordia alliodora, and Cojoba arborea. Soil physical and chemical characteristics were also analysed, and soil type recognition was performed with the Reference Base for Soil FAO-ISRIC World-SICS. Mycorrhizal colonization was determined by the method of clearing and staining roots with trypan blue; total percentage of colonization was estimated by the Linderman-Biermann method. Spores were extracted for counting and identifying morphospecies from each soil sample, those with more effectiveness were selected and inoculated in the four tree species, based upon a completely random design there were evaluated height, number of leaves, total dry weight and foliar area. Main results: Average mycorrhizal colonization percentage was 45% from natural conditions, samples one and four showed 80% of AMF-colonization. Average number of spores was 617 in 100 g-1 of dry soil. Forty-seven AMF-morphospecies were identified. After eight months significant differences were observed in root colonization, height, number of leaves, total dry weight, leaf area and foliar analysis of N5+, P5+ and K+ on plants inoculated with rhizosphere samples of L. styraciflua. Terminalia amazonia and

  13. Effectiveness of native arbuscular mycorrhiza on the growth of four tree forest species from the Santa Marta Mountain, Veracruz (Mexico)

    International Nuclear Information System (INIS)

    Retama-Ortiz, Y.; Ávila-Bello, C.H.; Alarcón, A.; Ferrera-Cerrato, R.

    2017-01-01

    Aim of the study: The aim of this work was to isolate consortia of arbuscular mycorrhizal fungi (AMF) associated to Liquidambar styraciflua in soils of the Santa Marta Mountain in Veracruz, and to select highly effective mycorrhizal consortia on promoting the growth of four tree forest species with economic and ecological importance. Area of study: Santa Marta Mountain, inside the buffer area of the Los Tuxtlas Biological Reserve in Veracruz (México). Materials and methods: Ten composite samples of rhizosphere soil were collected from L. styraciflua trees of 13-15 cm DBH (diameter at breast height). Roots were fixed in FAA solution to determine the mycorrhizal colonization percentage, the abundance of morphospecies, and its effectiveness in promoting the growth of L. styraciflua, Terminalia amazonia, Cordia alliodora, and Cojoba arborea. Soil physical and chemical characteristics were also analysed, and soil type recognition was performed with the Reference Base for Soil FAO-ISRIC World-SICS. Mycorrhizal colonization was determined by the method of clearing and staining roots with trypan blue; total percentage of colonization was estimated by the Linderman-Biermann method. Spores were extracted for counting and identifying morphospecies from each soil sample, those with more effectiveness were selected and inoculated in the four tree species, based upon a completely random design there were evaluated height, number of leaves, total dry weight and foliar area. Main results: Average mycorrhizal colonization percentage was 45% from natural conditions, samples one and four showed 80% of AMF-colonization. Average number of spores was 617 in 100 g-1 of dry soil. Forty-seven AMF-morphospecies were identified. After eight months significant differences were observed in root colonization, height, number of leaves, total dry weight, leaf area and foliar analysis of N5+, P5+ and K+ on plants inoculated with rhizosphere samples of L. styraciflua. Terminalia amazonia and

  14. Effects of arbuscular mycorrhizae on growth and mineral nutrition of greenhouse propagated fruit trees from diverse geographic provenances

    Directory of Open Access Journals (Sweden)

    Guissou, T.

    2016-01-01

    Full Text Available Description of the subject. Arbuscular mycorrhizal (AM fungi are known to promote plant growth by enhancing mineral uptake in nutrient deficient soils. These beneficial effects on plant growth may vary considerably between cultivars of a given species and between plant species originating from different locations. Objectives. The present experiment evaluated the response of three Sahelian fruit trees: néré (Parkia biglobosa [Jacq.] G.Don, tamarind (Tamarindus indica L., and jujube (Ziziphus mauritiana Lam., originating from five different geographic provenances, to mycorrhizal colonization, evaluate their respective mycorrhizal dependency (MD and analyze their leaf and stem mineral composition. Method. Trees were cultivated in a nursery on pre-sterilized soil substrate low in available P (2.18 μg·g-1 with or without inoculum of Glomus aggregatum (Schenck & Smith emend. Koske. The experiment was arranged in a factorial design for each fruit tree species separately: 5 provenances x 2 AM treatments (inoculated and non-inoculated [control] with 10 replicates per treatment. Plants were harvested six months after inoculation and different parameters were measured. Results. Overall, the results showed significant provenance variations in the plant response to mycorrhizal inoculation. Néré mycorrhizal plants, from two seed sources, tamarind and jujube plants from one seed source had significant higher dry weight and shoot height than those from other provenances. Jujube plants from 3 out of the 5 provenances showed significant higher MD. It then appears that seed provenance happened to be determinant even though AM-root colonization levels (80-90% do not vary much from one provenance to another. In all cases, the fruit trees benefited from AM fungi with increased N, P and K mineral uptake in aerial parts. In particular P uptake was proportional to MD concentration in AM-jujube plants. Conclusions. These results demonstrate the importance of

  15. 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

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

    African Journals Online (AJOL)

    Jane

    2011-08-01

    Aug 1, 2011 ... Khajehzadeh, 1996). Mycorrhiza is a mutual symbiosis between thallus of some fungi and the root of organic plants. In nature, mycorrhiza is important in satisfying the needs of the plants for water and nutrition. Among the microorganisms living in the soil, arbuscular mycorrhiza fungi are especially important ...

  17. Increased Phosphorus Uptake by Wheat and Field Beans Inoculated with a Phosphorus-Solubilizing Penicillium bilaji Strain and with Vesicular-Arbuscular Mycorrhizal Fungi.

    Science.gov (United States)

    Kucey, R M

    1987-12-01

    Greenhouse and field experiments were conducted to test the effect of a P-solubilizing isolate of Penicillium bilaji on the availability of Idaho rock phosphate (RP) in a calcareous soil. Under controlled greenhouse conditions, inoculation of soils with P. bilaji along with RP at 45 mug of P per g of soil resulted in plant dry matter production and P uptake by wheat (Triticum aestivum) and beans (Phaseolus vulgaris) that were not significantly different from the increases in dry matter production and P uptake caused by the addition of 15 mug of P per g of soil as triple superphosphate. Addition of RP alone had no effect on plant growth. Addition of vesicular-arbuscular mycorrhizal fungi was necessary for maximum effect in the sterilized soil in the greenhouse experiment. Under field conditions, a treatment consisting of RP (20 kg of P per ha of soil) plus P. bilaji plus straw resulted in wheat yields and P uptake equivalent to increases due to the addition of monoammonium phosphate added at an equivalent rate of P. RP added alone had no effect on wheat growth or P uptake. The results indicate that a biological system of RP solubilization can be used to increase the availability of RP added to calcareous soils.

  18. Pigeon Pea and Cowpea-Based Cropping Systems Improve Vesicular Arbuscular Mycorrhizal Fungal Colonisation of Subsequent Maize on the Alfisols in Central Malawi

    Directory of Open Access Journals (Sweden)

    Keston O. W. Njira

    2017-01-01

    Full Text Available Mycorrhizal associations contribute to the sustainability of crop production systems through their roles in nutrient cycling and other benefits in the soil-plant ecosystems. A two-year study was conducted on the Alfisols of Lilongwe and Dowa districts, Central Malawi, to assess the vesicular-arbuscular mycorrhizal (VAM fungal colonisation levels in pigeon pea, cowpea, and maize grown in sole cropping, legume-cereal, and legume-legume intercropping systems and in the maize grown in short rotation (year 2 as influenced by the previous cropping systems and N fertilizer application. The gridline intersect method was used to assess the VAM fungal colonisation levels. Results showed that all treatments that included legumes whether grown as sole crop, in legume-cereal or in legume-legume cropping systems in the previous year, had significantly higher (P < 0.05 VAM fungal colonisation of the rotational maize crop roots by a range 39% to 50% and 19% to 47% than those in maize supplied and not supplied with N fertilizer, respectively, in a maize-maize short rotation, at the Lilongwe site. A similar trend was reported for the Dowa site. Furthermore, there were positive correlations between VAM fungal colonisation and the plant P content, dry matter yield, and nodule numbers. Further studies may help to assess the diversity of VAM fungal species in Malawi soils and identify more adaptive ones for inoculation studies.

  19. RNA-seq Transcriptional Profiling of an Arbuscular Mycorrhiza Provides Insights into Regulated and Coordinated Gene Expression in Lotus japonicus and Rhizophagus irregularis.

    Science.gov (United States)

    Handa, Yoshihiro; Nishide, Hiroyo; Takeda, Naoya; Suzuki, Yutaka; Kawaguchi, Masayoshi; Saito, Katsuharu

    2015-08-01

    Gene expression during arbuscular mycorrhizal development is highly orchestrated in both plants and arbuscular mycorrhizal fungi. To elucidate the gene expression profiles of the symbiotic association, we performed a digital gene expression analysis of Lotus japonicus and Rhizophagus irregularis using a HiSeq 2000 next-generation sequencer with a Cufflinks assembly and de novo transcriptome assembly. There were 3,641 genes differentially expressed during arbuscular mycorrhizal development in L. japonicus, approximately 80% of which were up-regulated. The up-regulated genes included secreted proteins, transporters, proteins involved in lipid and amino acid metabolism, ribosomes and histones. We also detected many genes that were differentially expressed in small-secreted peptides and transcription factors, which may be involved in signal transduction or transcription regulation during symbiosis. Co-regulated genes between arbuscular mycorrhizal and root nodule symbiosis were not particularly abundant, but transcripts encoding for membrane traffic-related proteins, transporters and iron transport-related proteins were found to be highly co-up-regulated. In transcripts of arbuscular mycorrhizal fungi, expansion of cytochrome P450 was observed, which may contribute to various metabolic pathways required to accommodate roots and soil. The comprehensive gene expression data of both plants and arbuscular mycorrhizal fungi provide a powerful platform for investigating the functional and molecular mechanisms underlying arbuscular mycorrhizal symbiosis. © The Author 2015. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  20. 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

  1. Effect of two vesicular-arbuscular mycorrhizal fungi on the growth of micropropagated potato plantlets and on the extent of disease caused by Rhizoctonia solani.

    Science.gov (United States)

    Yao, M K; Tweddell, R J; Désilets, H

    2002-10-01

    Two micropropagated potato cultivars, Goldrush and LP89221, were inoculated into sowing trays with either Glomus etunicatum or G. intraradices in a greenhouse. After 2 weeks, plantlets were transplanted into pots and roots were challenged 7 days later with Rhizoctonia solani. At different times after R. solani infection, disease severity, mortality rate, root colonization levels, various growth parameters, and shoot mineral content were evaluated. In Goldrush, only inoculation with G. etunicatum led to a significant reduction in disease severity, ranging between 60.2% and 71.2%, on both shoot and crown. This decrease was not observed in LP89221. Compared with the control plantlets, inoculation of Goldrush with G. etunicatum or G. intraradices reduced significantly the mortality rate by 77% and 26%, respectively, whereas vesicular-arbuscular mycorrhizal (VAM) fungi did not significantly influence the mortality rate in LP89221. In Goldrush, inoculation with G. etunicatum significantly increased shoot fresh weight, root dry weight and the number of tubers produced per plant, whereas G. intraradices only significantly increased the number of tubers. Tuber and root fresh weights of both potato cultivars were significantly reduced by R. solani infection. However, R. solani-infected plantlets of both Goldrush and LP89221, inoculated with G. etunicatum, produced significantly greater tuber fresh weight than non-VAM plantlets. In R. solani-infected plantlets of Goldrush but not LP89221, G. etunicatum and G. intraradices increased root fresh weight by approximately 140.3% and 76.5%, respectively, compared with non-VAM plants. The potato cultivars Goldrush and LP89221 responded differently to VAM fungal inoculation and to R. solani infection in terms of shoot mineral content.

  2. A novel gene whose expression in Medicago truncatula roots is suppressed in response to colonization by vesicular-arbuscular mycorrhizal (VAM) fungi and to phosphate nutrition.

    Science.gov (United States)

    Burleigh, S H; Harrison, M J

    1997-05-01

    A cDNA clone (Mt4) was isolated as a result of a differential screen to identify genes showing altered expression during the interaction between Medicago truncatula and the vesicular-arbuscular mycorrhizal (VAM) fungus Glomus versiforme. Mt4 represents a M. truncatula mRNA that contains numerous short open reading frames, the two longest of which are predicted to encode polypeptides of 51 amino acids each. One of these open reading frames shares a short region of identity with a phosphate starvation-inducible gene from tomato. Mt4 gene expression is regulated in response to colonization by mycorrhizal fungi: transcripts were detected in non-colonized roots and levels decreased in both M. truncatula and M. sativa (alfalfa) roots after colonization by G. versiforme. Transcript levels also decreased during the incomplete interaction between G. versiforme and a M. sativa mycorrhizal minus (myc-) line, indicating that the down-regulation of this gene occurs early during the interaction between the fungus and its host plant. Phosphate levels in the nutrient media also affected the expression of the Mt4 gene: transcripts were present in the roots of plants grown under phosphate-deficient conditions, but were undetectable in the roots of plants grown under phosphate sufficient conditions. Furthermore, expression was only observed when plants were grown under nitrogen-sufficient conditions. Northern blot analyses indicate that Mt4 transcripts are present primarily in roots and barely detectable in stems or leaves. Thus, Mt4 represents a M. truncatula gene whose expression is regulated in response to both colonization by mycorrhizal fungi and to the phosphate status of the plant.

  3. Consequences of pre-inoculation with native arbuscular mycorrhizae on root colonization and survival of Artemisia tridentata ssp. wyomingensis (Wyoming big sagebrush) seedlings after transplanting

    Science.gov (United States)

    Bill Eugene Davidson

    2015-01-01

    Inoculation of seedlings with arbuscular mycorrhizal fungi (AMF) is a common practice aimed at improving seedling establishment. The success of this practice largely depends on the ability of the inoculum to multiply and colonize the growing root system after transplanting. These events were investigated in Artemisia tridentata ssp. wyomingensis (Wyoming big sagebrush...

  4. Influence of Species of Vesicular-Arbuscular Mycorrhizal Fungi and Phosphorus Nutrition on Growth, Development, and Mineral Nutrition of Potato (Solanum tuberosum L.).

    Science.gov (United States)

    McArthur, DAJ.; Knowles, N. R.

    1993-07-01

    Growth, development, and mineral physiology of potato (Solanum tuberosum L.) plants in response to infection by three species of vesicular-arbuscular mycorrhizal (VAM) fungi and different levels of P nutrition were characterized. P deficiency in no-P and low-P (0.5 mM) nonmycorrhizal plants developed between 28 and 84 d after planting. By 84 d after planting, P deficiency decreased plant relative growth rate such that no-P and low-P plants had, respectively, 65 and 45% less dry mass and 76 and 55% less total P than plants grown with high P (2.5 mM). A severe reduction in leaf area was also evident, because P deficiency induced a restriction of lateral bud growth and leaf expansion and, also, decreased the relative plant allocation of dry matter to leaf growth. Root growth was less influenced by P deficiency than either leaf or stem growth. Moreover, P-deficient plants accumulated a higher proportion of total available P than high-P plants, indicating that P stress had enhanced root efficiency of P acquisition. Plant P deficiency did not alter the shoot concentration of N, K, Mg, or Fe; however, the total accumulation of these mineral nutrients in shoots of P-stressed plants was substantially less than that of high-P plants. P uptake by roots was enhanced by each of the VAM symbionts by 56 d after planting and at all levels of abiotic P supply. Species differed in their ability to colonize roots and similarly to produce a plant growth response. In this regard, Glomus intraradices (Schenck and Smith) enhanced plant growth the most, whereas Glomus dimorphicum (Boyetchko and Tewari) was least effective, and Glomus mosseae ([Nicol. and Gerd.] Gerd. and Trappe) produced an intermediate growth response. The partial alleviation of P deficiency in no-P and low-P plants by VAM fungi stimulated uptake of N, K, Mg, Fe, and Zn. VAM fungi enhanced shoot concentrations of P, N, and Mg by 28 d after planting and, through a general improvement of overall plant mineral nutrition

  5. 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.

  6. Chromium resistance of dandelion (Taraxacum platypecidum Diels.) and bermudagrass (Cynodon dactylon [Linn.] Pers.) is enhanced by arbuscular mycorrhiza in Cr(VI)-contaminated soils.

    Science.gov (United States)

    Wu, Song-Lin; Chen, Bao-Dong; Sun, Yu-Qing; Ren, Bai-Hui; Zhang, Xin; Wang, You-Shan

    2014-09-01

    In a greenhouse pot experiment, dandelion (Taraxacum platypecidum Diels.) and bermudagrass (Cynodon dactylon[Linn.] Pers.), inoculated with and without arbuscular mycorrhizal fungus (AMF) Rhizophagus irregularis, were grown in chromium (Cr)-amended soils (0 mg/kg, 5 mg/kg, 10 mg/kg, and 20 mg/kg Cr[VI]) to test whether arbuscular mycorrhizal (AM) symbiosis can improve Cr tolerance in different plant species. The experimental results indicated that the dry weights of both plant species were dramatically increased by AM symbiosis. Mycorrhizal colonization increased plant P concentrations and decreased Cr concentrations and Cr translocation from roots to shoots for dandelion; in contrast, mycorrhizal colonization decreased plant Cr concentrations without improvement of P nutrition in bermudagrass. Chromium speciation analysis revealed that AM symbiosis potentially altered Cr species and bioavailability in the rhizosphere. The study confirmed the protective effects of AMF on host plants under Cr contaminations. © 2014 SETAC.

  7. Arbuscular mycorrhiza enhanced arsenic resistance of both white clover (Trifolium repens Linn.) and ryegrass (Lolium perenne L.) plants in an arsenic-contaminated soil

    International Nuclear Information System (INIS)

    Dong Yan; Zhu Yongguan; Smith, F. Andrew; Wang Youshan; Chen Baodong

    2008-01-01

    In a compartmented cultivation system, white clover (Trifolium repens Linn.) and ryegrass (Lolium perenne L.), with their roots freely intermingled, or separated by 37 μm 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

  8. 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.

  9. Plant growth responses to elevated atmospheric CO2 are increased by phosphorus sufficiency but not by arbuscular mycorrhizas

    DEFF Research Database (Denmark)

    Jakobsen, Iver; Smith, Sally E.; Smith, F. Andrew

    2016-01-01

    Capturing the full growth potential in crops under future elevated CO2 (eCO2) concentrations would be facilitated by improved understanding of eCO2 effects on uptake and use of mineral nutrients. This study investigates interactions of eCO2, soil phosphorus (P), and arbuscular mycorrhizal (AM......) symbiosis in Medicago truncatula and Brachypodium distachyon grown under the same conditions. The focus was on eCO2 effects on vegetative growth, efficiency in acquisition and use of P, and expression of phosphate transporter (PT) genes. Growth responses to eCO2 were positive at P sufficiency, but under low...

  10. 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.

  11. Soil microbiology in land reclamation volume II - mycorrhizae

    Energy Technology Data Exchange (ETDEWEB)

    Graves, D.H. (ed.)

    1984-01-01

    This volume contains three separate reports: RRTAC 84-4 (Greenhouse pot studies dealing with amendment of oil sand tailings: effects of peat, sewage sludge and fertilizer on plant growth, mycorrhizae and microbial activity); RRTAC 84-8 (Vesicular-arbuscular mycorrhizal (VAM) development of slender wheatgrass on amended oil sand tailings and subalpine coal mines spoil); RRTAC 84-7 (Ectomycorrhizae in amended oil sand tailings and subalpine coal mine spoil and in undisturbed Jack pine and spruce stands). In the first report mixtures of two peats were used to amend oil sand tailings and either mineral fertilizers or sewage sludge were added at different rates. The growth of slender wheat grass and jack pine grown in the greenhouse in these media were monitored. In the second report the VAM development of slender wheatgrass was monitored over a 4 year period; in the third the mycorrhizal status of jack pine and bear berry grown in oil sand tailings treated with various amendments and of white spruce and willow grown in subalpine coal mine spoil were monitored over the same period.

  12. Micorriza arbuscular em plantações de Eucalyptus cloeziana F. Muell no litoral norte da Bahia, Brasil Arbuscular mycorrhiza in Eucalyptus cloeziana F. Muell plantations in the north littoral of Bahia, Brazil

    Directory of Open Access Journals (Sweden)

    Cristiano V.M. Araújo

    2004-09-01

    Full Text Available As micorrizas arbusculares são de longa data conhecidas e exploradas devido à importância ecológica e aos efeitos no crescimento e na nutrição das plantas. Eucalyptus cloeziana F. Muell, particularmente nas áreas em estudo, apresenta comportamento diferenciado quando comparado com outras espécies de eucaliptos, instalando-se em sítios de solos pobres e textura arenosa, com crescimento reduzido, dificuldades para a formação das mudas e problemas nutricionais. Objetivando avaliar a percentagem de colonização radicular e a densidade de esporos de fungos micorrízicos arbusculares em plantações de E. cloeziana, foram realizadas coletas de solo rizosférico e de raízes em 20 áreas, distribuídas em seis municípios do Estado da Bahia, Brasil. Os resultados médios da percentagem de colonização variaram de 10% a 96,66% e a densidade de esporos variou de 3 a 110 esporos/50cm³ de solo, demonstrando a grande suscetibilidade do E. cloeziana à micorrização.The arbuscular mycorrhizal are known and explored long ago due to the ecological significance and the effects in the growth and nutrition of the plants. Eucalyptus cloeziana F. Muell, particularly in the studied sites, exhibit differenced behaviour when compared with other eucaliptus species, establishing in sites of the poor soils and sandy texture, with reduced growth, difficulty to formation of the seedling and nutritional problems. Aiming to evaluate the percentage of mycorrhizal colonization, as well as the density of arbuscular mycorrhizal fungi spores in E. cloeziana plantations, rhizospheric soil and roots samples were collected in twenty sites, distributed in six municipalities of Bahia state, Brazil. The mean results of percentage root colonization ranged from 10 to 96.66% and spore number ranged from 3 to 110 spores/50cm³ soil, demonstrating high susceptibility of the E. cloeziana to mycorrhization.

  13. Mycorrhiza of Dryopteris carthusiana in southern Poland

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    Juliusz Unrug

    2014-08-01

    Full Text Available The research on mycorrhiza of Dryopteris carthusiana from natural sites and those contaminated by heavy metals (Niepołomice Forest, both on lowlands and mountainous areas in Poland, was carried out. Mycorrhizal colonization of Arum-type was higher in ferns growing on tree stumps than in specimens developing directly on the soil. Additionally, an increase in mycorrhiza intensity and arbuscular richness with the rising ground humidity was observed. In comparison to natural sites, mycorrhizas from the areas contaminated by heavy metals were much less developed and the roots were often infected by parasites. Two morphotypes of mycorrhizal fungi have been described The most common was a fine endophyte (Glomales.

  14. Can arbuscular mycorrhiza fungi and NPK fertilizer suppress nematodes and improve tuber yield of yam (Dioscorea rotundata ‘cv’ ewuru?

    Directory of Open Access Journals (Sweden)

    Gani Oladejo Kolawole

    2018-04-01

    Full Text Available Poor soil fertility and nematodes limit yam tuber yield and quality. Arbuscular mycorrhizal fungi (AMF and fertilizers may suppress nematodes and improve yam productivity. We evaluated the extent AMF and fertilizer suppressed nematodes and improved yam performance. Tuber weight, mycorrhizal colonization of roots and nematode populations were evaluated with eight treatments; Control (No amendments, 90-50-75, kg N- P2O5-K2O ha-1 (NPK, (AMF (2g/kg soil, nematodes (5000 juvenile/pot, and their combinations. Tuber weight was higher in NPK+AMF and NPK+nematode treatments than AMF+nematode. NPK+AMF improved tuber weight by 17.5% and 32% compared with sole NPK or AMF respectively. Compared with control, nematodes did not reduce tuber weight but, AMF+nematode reduced it by 49.4%. NPK reduced AMF colonization of roots and reduced nematode population on tuber, in roots and soil by 34%, 42.6% and 41% respectively. NPK+AMF treatment was superior to either NPK or AMF in improving tuber yield while NPK was superior to AMF in suppressing nematodes in roots, soil, and tuber.

  15. Effects of arbuscular mycorrhizae on tomato yield, nutrient uptake, water relations, and soil carbon dynamics under deficit irrigation in field conditions.

    Science.gov (United States)

    Bowles, Timothy M; Barrios-Masias, Felipe H; Carlisle, Eli A; Cavagnaro, Timothy R; Jackson, Louise E

    2016-10-01

    Plant strategies to cope with future droughts may be enhanced by associations between roots and soil microorganisms, including arbuscular mycorrhizal (AM) fungi. But how AM fungi affect crop growth and yield, together with plant physiology and soil carbon (C) dynamics, under water stress in actual field conditions is not well understood. The well-characterized mycorrhizal tomato (Solanum lycopersicum L.) genotype 76R (referred to as MYC+) and the mutant nonmycorrhizal tomato genotype rmc were grown in an organic farm with a deficit irrigation regime and control regime that replaced evapotranspiration. AM increased marketable tomato yields by ~25% in both irrigation regimes but did not affect shoot biomass. In both irrigation regimes, MYC+ plants had higher plant nitrogen (N) and phosphorus (P) concentrations (e.g. 5 and 24% higher N and P concentrations in leaves at fruit set, respectively), 8% higher stomatal conductance (gs), 7% higher photosynthetic rates (Pn), and greater fruit set. Stem water potential and leaf relative water content were similar in both genotypes within each irrigation regime. Three-fold higher rates of root sap exudation in detopped MYC+ plants suggest greater capacity for water uptake through osmotic driven flow, especially in the deficit irrigation regime in which root sap exudation in rmc was nearly absent. Soil with MYC+ plants also had slightly higher soil extractable organic C and microbial biomass C at anthesis but no changes in soil CO2 emissions, although the latter were 23% lower under deficit irrigation. This study provides novel, field-based evidence for how indigenous AM fungi increase crop yield and crop water use efficiency during a season-long deficit irrigation and thus play an important role in coping with increasingly limited water availability in the future. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Arbuscular mycorrhiza alters metal uptake and the physiological response of Coffea arabica seedlings to increasing Zn and Cu concentrations in soil.

    Science.gov (United States)

    Andrade, S A L; Silveira, A P D; Mazzafera, P

    2010-10-15

    Studies on mycorrhizal symbiosis effects on metal accumulation and plant tolerance are not common in perennial crops under metal stress. The objective of this study was to evaluate the influence of mycorrhization on coffee seedlings under Cu and Zn stress. Copper (Cu) and zinc (Zn) uptake and some biochemical and physiological traits were studied in thirty-week old Coffea arabica seedlings, in response to the inoculation with arbuscular mycorrhizal fungi (AMF) and to increasing concentrations of Cu or Zn in soil. The experiments were conducted under greenhouse conditions in a 2×4 factorial design (inoculation or not with AMF and 0, 50, 150 and 450mgkg(-1) Cu or 0, 100, 300 and 900mgkg(-1) Zn). Non-mycorrhizal plants maintained a hampered and slow growth even in a soil with appropriate phosphorus (P) levels for this crop. As metal levels increased in soil, a greater proportion of the total absorbed metals were retained by roots. Foliar Cu concentrations increased only in non-mycorrhizal plants, reaching a maximum concentration of 30mgkg(-1) at the highest Cu in soil. Mycorrhization prevented the accumulation of Cu in leaves, and mycorrhizal plants showed higher Cu contents in stems, which indicated a differential Cu distribution in AMF-associated or non-associated plants. Zn distribution and concentrations in different plant organs followed a similar pattern independently of mycorrhization. In mycorrhizal plants, only the highest metal concentrations caused a reduction in biomass, leading to significant changes in some biochemical indicators, such as malondialdehyde, proline and amino acid contents in leaves and also in foliar free amino acid composition. Marked differences in these physiological traits were also found due to mycorrhization. In conclusion, AMF protected coffee seedlings against metal toxicity. Copyright © 2010 Elsevier B.V. All rights reserved.

  17. The effects of mineral nitrogen limitation, competition, arbuscular mycorrhiza, and their respective interactions, on morphological and chemical plant traits of Plantago lanceolata.

    Science.gov (United States)

    Pankoke, Helga; Höpfner, Ingo; Matuszak, Agnieszka; Beyschlag, Wolfram; Müller, Caroline

    2015-10-01

    Plants are sessile organisms that suffer from a multitude of challenges such as abiotic stress or the interactions with competitors, antagonists and symbionts, which influence their performance as well as their eco-physiological and biochemical responses in complex ways. In particular, the combination of different stressors and their impact on plant biomass production and the plant's ability to metabolically adjust to these challenges are less well understood. To study the effects of mineral nitrogen (N) availability, interspecific competition and the association with arbuscular mycorrhizal fungi (AMF) on biomass production, biomass allocation patterns (root/shoot ratio, specific leaf area) and metabolic responses, we chose the model organism Plantago lanceolata L. (Plantaginaceae). Plants were grown in a full factorial experiment. Biomass production and its allocation patterns were assessed at harvest, and the influence of the different treatments and their interactions on the plant metabolome were analysed using a metabolic fingerprinting approach with ultra-high performance liquid chromatography coupled with time-of-flight-mass spectrometry. Limited supply of mineral N caused the most pronounced changes with respect to plant biomass and biomass allocation patterns, and altered the concentrations of more than one third of the polar plant metabolome. Competition also impaired plant biomass production, yet affected the plant metabolome to a much lesser extent than limited mineral N supply. The interaction of competition and limited mineral N supply often caused additive changes on several traits. The association with AMF did not enhance biomass production, but altered biomass allocation patterns such as the root/shoot ratio and the specific leaf area. Interestingly, we did not find significant changes in the plant metabolome caused by AMF. A targeted analysis revealed that only limited mineral N supply reduced the concentrations of one of the main target defence

  18. Fungos micorrízicos arbusculares em estéril revegetado com Acacia mangium, após mineração de bauxita Colonization of arbuscular mycorrhizae fungi in substrate, after bauxite mining, vegetated with Acacia mangium

    Directory of Open Access Journals (Sweden)

    Ana Lucy Caproni

    2005-06-01

    Full Text Available O objetivo deste trabalho foi avaliar a composição das comunidades de FMAs em áreas revegetadas com Acacia mangium após a mineração de bauxita na região de Porto Trombetas, PA. Foram coletadas amostras de solo compostas nos períodos seco e chuvoso, em áreas revegetadas com Acacia mangium, que receberam inóculos de Glomus clarum e Gigaspora margarita, com 1 e 5 anos de idade. Os solos foram revegetados sem a reposição do horizonte superficial orgânico. Os esporos dos fungos micorrízicos arbusculares (FMAs foram extraídos e identificados através de suas características morfológicas. Analisou-se a densidade de esporos e de espécies em cada amostra, a densidade relativa e a freqüência de ocorrência de cada espécie por período de amostragem, além do índice de abundância e freqüência (IAF. Sob o plantio de mudas de A. mangium, a densidade de esporos de FMAs foi elevada e aumentou com a idade, enquanto o número de espécies não variou. Glomus clarum produz alta densidade de esporos na fase inicial do plantio e declina com o tempo, e Gigaspora margarita não esporula nas condições edafoclimáticas locais. A maioria das espécies de FMA não apresenta o mesmo padrão de esporulação nos períodos seco e chuvoso.The objective of this work was to monitor the establishment of Gigaspora margarita and Glomus clarum in reclaimed areas after the bauxite mining in Porto Trombetas, PA, Brazil. Soil samples were collected during the dry and rainy periods under one and five-year-old Acacia mangium trees grown from seedlings that had been inoculated with Glomus clarum and Gigaspora margarita. The exposed subsoil was managed without replacing the organic soil layer. FMA spores were extracted and identified through their morphologic characteristics. Spore density and frequency of each species were determined in each sampling The index of abundance and frequency (IAF were estimated for all samples. Under A. mangium the arbuscular

  19. Arbuscular mycorrhiza and kinetic parameters of phosphorus absorption by bean plants Micorriza arbuscular e os parâmetros cinéticos de absorção de fósforo pelo feijoeiro

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    Adriana Parada Dias da Silveira

    2004-04-01

    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.Os mecanismos envolvidos na maior absorção de P pela planta micorrizada ainda não estão totalmente esclarecidos, atribuindo-se, em parte, ao aumento no número de sítios de absorção promovido pela hifa e/ou maior afinidade dos carregadores da hifa ou da raiz colonizada ao P. Avaliou-se o efeito da micorriza formada por Glomus etunicatum nos parâmetros cinéticos da absorção radicular de P e no influxo de P em feijoeiro, cultivar IAC-Carioca, em duas épocas do ciclo da planta

  20. Aspectos ecológicos de fungos micorrízicos vesículo-arbusculares da mata tropical úmida da Ilha do Cardoso, SP, Brasil Ecological aspects of mycorrhizal vesicular-arbuscular fungi of the tropical humid forest of Cardoso Island, SP, Brazil

    Directory of Open Access Journals (Sweden)

    Sandra F. B Trufem

    1990-12-01

    Full Text Available No período de agosto/1984 a maio/1987, em nove ocasiões, foram coletadas 300 amostras de solo da rizosfera de 35 espécies de plantas nativas da mata tropical úmida do Parque Estadual da Ilha do Cardoso, SP, Brasil, para a investigação da ocorrência de fungos micorrízicos vesículo-arbusculares (MVA ea obtenção de dados sobre aspectos ecológicos desses microrganismos. Foram verificados 35 taxa de fungos MV A, sete dos quais espécies novas. Os esporos qué ocorreram em maior quantidade foram os de Acaulospora foveata Trappe & Janos, Acaulospora scrobiculata Trappe, Glomus etunicatum Becker & Gerd.. Glomus geosporum (Nicol. & Gerd. Walker, Glomus macrocarpum Tul. & Tul. e Glomus microcarpum Tul. & Tul. As plantas cujas rizosferas apresentaram maior número de esporos de fungos MV A foram as de Blechnum serrulatum L.C. Rich., Euterpe edulis Mart, Neomarica caerulia Sprague, Geonoma elegans Mart, e Piper aduncum L. A maior diversidade de espécies de fugnos MV A ocorreu nas rizosferas de Aphettandra sp., Geonoma elegans Mart e Leandra barbinervis Cogn. Verificouse que houve predominancia de espécies de fungos micorrízicos vesículo-arbusculares clamidospóricas sobre as azigospóricas, bem como que a quantidade de esporos em urna dada rizosfera está diretamente relacionada com a diversidade. Glomus monosporum Gerd. & Trappe e as espécies de Sclerocystis podem ser apontadas como características do ecossistema estudado, que apresentou a média de 50,04 esporos/ 100g de solo.From August/1984 to May/1987, 300 soil samples were collected from the rhizospheres of 35 species of native plants of Parque Estadual da Ilha do Cardoso, SP, Brazil, in a wet tropical forest, to investigate the occurrence and some ecological aspects of vesicular-arbuscular mycorrhizal (VAM fungi. Thirty five taxa of VA M fungi were reported, seven of them as new species. The most numerous VA M fungal spores belong to Acaulospora foveata Trappe & Janos, Acaulospora

  1. Arbuscular mycorrhizal fungi associating with roots of Alnus and Rubus in Europe and the Middle East

    Czech Academy of Sciences Publication Activity Database

    Pölme, S.; Öpik, M.; Moora, M.; Zobel, M.; Kohout, Petr; Oja, J.; Köljalg, U.; Tedersoo, L.

    2016-01-01

    Roč. 24, Part A (2016), s. 27-34 ISSN 1754-5048 Institutional support: RVO:67985939 Keywords : arbuscular mycorrhiza * fungi * biogeography Subject RIV: EH - Ecology, Behaviour Impact factor: 3.219, year: 2016

  2. Quantification of arbuscular mycorrhizal fungal DNA in roots: how important is material preservation?

    Czech Academy of Sciences Publication Activity Database

    Janoušková, Martina; Püschel, David; Hujslová, M.; Slavíková, R.; Jansa, J.

    2015-01-01

    Roč. 25, č. 3 (2015), s. 205-214 ISSN 0940-6360 Institutional support: RVO:67985939 Keywords : arbuscular mycorrhiza * quantitative real-time PCR * sample preservation Subject RIV: EF - Botanics Impact factor: 3.252, year: 2015

  3. Distribution patterns of arbuscular mycorrhizal and non-mycorrhizal plant species in Germany

    Czech Academy of Sciences Publication Activity Database

    Menzel, A.; Hempel, S.; Manceur, A. M.; Götzenberger, Lars; Moora, M.; Rilling, M.C.; Zobel, M.; Kühn, I.

    2016-01-01

    Roč. 21, August 2016 (2016), s. 78-88 ISSN 1433-8319 Institutional support: RVO:67985939 Keywords : arbuscular mycorrhiza * distribution model * Central Europe Subject RIV: EH - Ecology, Behaviour Impact factor: 3.123, year: 2016

  4. The rise and fall of arbuscular mycorrhizal fungal diversity during ecosystem retrogression

    Czech Academy of Sciences Publication Activity Database

    Krüger, Manuela; Teste, F. P.; Laliberté, E.; Lambers, H.; Coghlan, M.; Zemunik, G.; Bunce, M.

    2015-01-01

    Roč. 24, č. 19 (2015), s. 4912-4930 ISSN 0962-1083 Institutional support: RVO:67985939 Keywords : arbuscular mycorrhiza * ecosystem retrogression * chronosequence Subject RIV: EH - Ecology, Behaviour Impact factor: 5.947, year: 2015

  5. Can Fertilization of Soil Select Less Mutualistic Mycorrhizae?

    Science.gov (United States)

    Johnson, Nancy Collins

    1993-11-01

    It has been noted previously that nutrient-stressed plants generally release more soluble carbohydrate in root exudates and consequently support more mycorrhizae than plants supplied with ample nutrients. Fertilization may select strains of vesicular-arbuscular mycorrhizal (VAM) fungi that are inferior mutualists if the same characteristics that make a VAM fungus successful in roots with a lowered carbohydrate content also reduce the benefits that the fungus provides a host plant. This two-phase study experimentally tests the hypothesis that fertilizing low-nutrient soil selects VAM fungi that are inferior mutualists. The first phase examines the effects of chemical fertilizers on the species composition of VAM fungal communities in long-term field plots. The second phase measures the effects of VAM fungal assemblages from fertilized and unfertilized plots on big bluestem grass grown in a greenhouse. The field results indicate that 8 yr of fertilization altered the species composition of VAM fungal communities. Relative abundance of Gigaspora gigantea, Gigaspora margarita, Scutellispora calospora, and Glomus occultum decreased while Glomus intraradix increased in response to fertilization. Results from the greenhouse experiment show that big bluestem colonized with VAM fungi from fertilized soil were smaller after 1 mo and produced fewer inflorescences at 3 mo than big bluestem colonized with VAM fungi from unfertilized soil. Fungal structures within big bluestem roots suggest that VAM fungi from fertilized soil exerted a higher net carbon cost on their host than VAM fungi from unfertilized soil. VAM fungi from fertilized soil produced fewer hyphae and arbuscules (and consequently provided their host with less inorganic nutrients from the soil) and produced as many vesicles (and thus provisioned their own storage structures at the same level) as fungi from unfertilized soil. These results support the hypothesis that fertilization selects VAM fungi that are inferior

  6. Colonização micorrízica arbuscular e tolerância ao mal-do-Panamá em mudas de banana-maçã Colonisation of arbuscular mycorrhiza and tolerance to Panama disease in seedlings of the maçã banana

    Directory of Open Access Journals (Sweden)

    Deusiane Batista Sampaio

    2012-09-01

    Full Text Available O objetivo desse trabalho foi avaliar o efeito da colonização micorrízica arbuscular na tolerância da bananeira, cv. Maçã, ao mal-do-Panamá, sob diferentes fontes de nutrientes. Utilizou-se um delineamento inteiramente casualizado com fatorial 2 x 4 [2 densidades de esporos de FMA nativos (D1 - 3.500 esporos kg-1 solo e D2 - 7.000 esporos kg-1 solo e 4 diferentes concentrações de fontes de nutrientes - três de solução nutritiva (SN 40%, SN 70% e SN 100% e uma de biofertilizante 100% (B4] com três repetições. Após o plantio inoculou-se Fusarium oxysporum f.sp. cubense e posteriormente avaliou-se matéria seca da parte aérea (MSPA, o teor de fósforo foliar (P, a colonização micorrízica, o pH do solo e o índice de severidade da doença (ID. As diferentes fontes de nutrientes influenciaram a matéria seca da parte aérea, o teor de fósforo, a colonização micorrízica e o índice de severidade da doença, porém não influenciaram o pH da solução do solo. O biofertilizante não atendeu à demanda nutricional das plantas, as quais se mostraram pouco desenvolvidas. Porém proporcionou intensa colonização micorrízica e menor índice de severidade da fusariose, o qual aumentou com a adubação mineral.The aim of this study was to evaluate the effect of the colonization of arbuscular mycorrhiza on the tolerance to Panama disease of the banana plant cv. maçã under different sources of nutrients. A completely randomized design was employed, having a 2 x 4 factorial [2 densities of native FMA spores (D1 - 3,500 spores kg-1 soil and D2 - 7000 spores kg-1 soil and four different concentrations of nutrient sources - three of a nutrient solution (SN 40%, SN 70% and SN 100% and a 100% solution of bio-fertiliser (B4], with three replications. After planting, the seedlings were inoculated with Fusarium oxysporum f.sp. cubense, and later the shoot dry matter, leaf phosphorus content, mycorrhizal colonization, soil pH and disease

  7. Plant nutrient transporter regulation in arbuscular mycorrhizas

    DEFF Research Database (Denmark)

    Burleigh, Stephen; Bechmann, I.E.

    2002-01-01

    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...

  8. Effect of Symbiosis of Arbuscular Mycorhiza and Like-endo Mycorhiza on Yield and Uptake of MacroandMicro Elements in Chickpea Genotypes (Cicer arietinum L.

    Directory of Open Access Journals (Sweden)

    M. J Arshadi

    2017-12-01

    Full Text Available Introduction Improving of nutrients absorption by biological approaches, in addition to emphasis on sustainable agriculture, will increase or stabilize crop yield. It seems that microorganisms such as mycorrhiza and rhizobium can improve the nutrients absorption in crops such as chickpea. Rhizobiums are effective to provide biological nitrogen for crops and mycorrhizal fungi are involved to supply biological phosphorus to the plants. Among them, the endo myccorihza (or Vesicular Arbuscular Mycorrhiza that is abbreviated VAM, in creation of symbiosis with the roots of crops such as legumes have been more successful. Of course, the mycorrhizal fungi and rhizobium bacteria before creating symbiosis with host plant, directly affect in the overlay in rhizosphere environment of host plant. Creating colonies in the roots by mycorrhizal fungi leads to conducive for forming nodulation of rhizobium. In other words, mycorrhiza fungi creats favorable conditions for the production of rhizobium nodules on the roots and also they affect on greater availability of phosphorus for nitrogenase enzymes involved in rhizobium bacteria. In contrast, rhizobiums affect in better absorption of nitrogen and followed by the synthesis of amino acids and amino acid availability for required mycorrhiza. It seems that this symbiotic relationship between plants, mycorrhizal and rhizobium can be either normal or adverse environmental conditions, which is effective in promoting the product of crop. However, the Triplet symbiosis of chickpea, mycorrhiza and rhizobium and also chickpea genotypes response to this symbiosis should be examined. Materials and Methods This study was conducted to investigate the inoculation of kabuli seeds of chickpea genotypes with arbuscular mycorrhiza and like - endomycorhiza, in 2014, in split plot by arrangement of two factors with a randomized complete block design and three replications in Research Field, Faculty of Agriculture, Ferdowsi

  9. Mycorrhizae and their potential use in the agricultural and forestry industries.

    Science.gov (United States)

    Peterson, R L; Piché, Y; Plenchette, C

    1984-01-01

    Mycorrhizal fungi associated with plant roots increase the absorption of nutrients, particularly phosphorus, and thus enhance the growth of crop plants and trees. Vesicular-arbuscular mycorrhizae (VAM) occur in approximately 90% of all vascular plants including most of the important agricultural species, whereas ectomycorrhizae are found in most of the economically important tree species of the temperate regions of the world, and in some tropical trees. These symbiotic associations are, therefore, important in crop and biomass production. For this reason they are receiving considerable attention in agriculture and forestry. Currently, VAM are utilized in fumigated soils, greenhouse crops, and in the reclamation of disturbed sites. Ectomycorrhizae are employed in the establishment of trees in nurseries, in reforestation programs, and in the production of containerized seedlings. Production of VAM and ectomycorrhiza inoculum for large scale projects is now feasible but many basic questions related to persistence of these fungi in field situations, competition with other microorganisms, and particularly the most efficient fungi to use for particular hosts remain largely unanswered.

  10. Glomus drummondii and G. walkeri, two new species of arbuscular mycorrhizal fungi (Glomeromycota).

    Science.gov (United States)

    Błaszkowski, Janusz; Renker, Carsten; Buscot, François

    2006-05-01

    Two new ectocarpic arbuscular mycorrhizal fungal species, Glomus drummondii and G. walkeri (Glomeromycota), found in maritime sand dunes of northern Poland and those adjacent to the Mediterranean Sea are described and illustrated. Mature spores of G. drummondii are pastel yellow to maize yellow, globose to subglobose, (58-)71(-85) micromdiam, or ovoid, 50-80x63-98 microm. Their wall consists of three layers: an evanescent, hyaline, short-lived outermost layer, a laminate, smooth, pastel yellow to maize yellow middle layer, and a flexible, smooth, hyaline innermost layer. Spores of G. walkeri are white to pale yellow, globose to subglobose, (55-)81(-95) micromdiam, or ovoid, 60-90x75-115 microm, and have a spore wall composed of three layers: a semi-permanent, hyaline outermost layer, a laminate, smooth, white to pale yellow middle layer, and a flexible, smooth, hyaline innermost layer. In Melzer's reagent, only the inner- and outermost layers stain reddish white to greyish rose in G. drummondii and G. walkeri, respectively. Both species form vesicular-arbuscular mycorrhizae in one-species cultures with Plantago lanceolata as the host plant. Phylogenetic analyses of the ITS and parts of the LSU of the nrDNA of spores placed both species in Glomus Group B sensu Schüssler et al. [Schüssler A, Schwarzott D, Walker C, 2001. A new fungal phylum, the Glomeromycota: phylogeny and evolution. Mycolological Research 105: 1413-1421.].

  11. 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

  12. 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

  13. 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.

  14. Alleviating salt stress in tomato inoculated with mycorrhizae: Photosynthetic performance and enzymatic antioxidants

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    Mohsen K.H. Ebrahim

    2017-11-01

    Full Text Available Tomato cultivars (Sultana-7 & Super Strain-B were germinated with various concentrations (0–200 mM of NaCl. Seed germination in the Super Strain-B was promoted by 25 mM NaCl. However, the germination of both cultivars was progressively inhibited by 50 and 100 mM NaCl and obstructed at 200 mM NaCl, and this response was more pronounced for Sultana-7. Therefore, Super Strain-B was selected for further investigation, such as growth under NaCl stress (50 & 100 mM and inoculation with vesicular-arbuscular mycorrhizal fungus (Glomus fasciculatum, VAMF. The leaves of Super Strain-B showed reduced mineral (N, P, K, Mg uptake and K/Na ratio as well as increased Na uptake and N/P ratio in response to salinity. Moreover, salinity decreased the chlorophyll (Chl contents coupled with an increase in Chl a/b, Hill-reaction activity, and quenched Chl a fluorescence emission. These changes reflect a disturbance in the structure, composition and function of the photosynthetic apparatus as well as the activity of photosystem 2. The superoxide dismutase and peroxidase activities of leaves were enhanced by salinity, whereas the catalase activity was decreased. Leaf polysaccharides and proteins as well as shoot biomass also decreased as a result of salinity, but the total soluble sugars and root to shoot ratio improved.VAMF enhanced both the photosynthesis and productivity of plants; thus, VAMF may alleviate the adverse effects of salinity in plants by increasing their salt tolerance. Although mycorrhizal infection showed a negative correlation with salinity, it remained relatively high (21 & 25% at 100 mM NaCl. Keywords: Mycorrhizae, tomato, salinity, minerals, photosynthetic performance and antioxidant enzymes

  15. Analyzing the soybean transcriptome during autoregulation of mycorrhization identifies the transcription factors GmNF-YA1a/b as positive regulators of arbuscular mycorrhization.

    Science.gov (United States)

    Schaarschmidt, Sara; Gresshoff, Peter M; Hause, Bettina

    2013-06-18

    Similarly to the legume-rhizobia symbiosis, the arbuscular mycorrhiza interaction is controlled by autoregulation representing a feedback inhibition involving the CLAVATA1-like receptor kinase NARK in shoots. However, little is known about signals and targets down-stream of NARK. To find NARK-related transcriptional changes in mycorrhizal soybean (Glycine max) plants, we analyzed wild-type and two nark mutant lines interacting with the arbuscular mycorrhiza fungus Rhizophagus irregularis. Affymetrix GeneChip analysis of non-inoculated and partially inoculated plants in a split-root system identified genes with potential regulation by arbuscular mycorrhiza or NARK. Most transcriptional changes occur locally during arbuscular mycorrhiza symbiosis and independently of NARK. RT-qPCR analysis verified nine genes as NARK-dependently regulated. Most of them have lower expression in roots or shoots of wild type compared to nark mutants, including genes encoding the receptor kinase GmSIK1, proteins with putative function as ornithine acetyl transferase, and a DEAD box RNA helicase. A predicted annexin named GmAnnx1a is differentially regulated by NARK and arbuscular mycorrhiza in distinct plant organs. Two putative CCAAT-binding transcription factor genes named GmNF-YA1a and GmNF-YA1b are down-regulated NARK-dependently in non-infected roots of mycorrhizal wild-type plants and functional gene analysis confirmed a positive role for these genes in the development of an arbuscular mycorrhiza symbiosis. Our results indicate GmNF-YA1a/b as positive regulators in arbuscular mycorrhiza establishment, whose expression is down-regulated by NARK in the autoregulated root tissue thereby diminishing subsequent infections. Genes regulated independently of arbuscular mycorrhization by NARK support an additional function of NARK in symbioses-independent mechanisms.

  16. 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

    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...... elevated CO2 suggest increased bacterial production, whereas the lower populations in response to presence of mycorrhiza suggest a depressing effect on bacterial production by AM colonisation. (C) 2002 Elsevier Science Ltd. All rights reserved....

  17. 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.

  18. Micorriza arbuscular em cupuaçu e pupunha cultivados em sistema agroflorestal e em monocultivo na Amazônia Central Arbuscular mycorrhiza in cupuaçu and peach palm cultivated in agroforestry and monoculture systems in the Central Amazon region

    Directory of Open Access Journals (Sweden)

    José Pereira da Silva Junior

    2006-05-01

    Full Text Available O objetivo deste trabalho foi avaliar a colonização micorrízica arbuscular em pupunha (Bactris gasipaes Kunth e cupuaçu (Theobroma grandiflorum (Willd ex Spring K. Schum cultivados em sistema agroflorestal e em monocultivo na Amazônia Central, em duas épocas do ano, e também identificar características anatômicas da formação dessa simbiose nessas espécies. Foram realizadas coletas de solo e raízes em duas estações, seca e chuvosa. A colonização micorrízica arbuscular no cupuaçu e na pupunha é alterada pelo sistema de manejo adotado, com taxas maiores de colonização no monocultivo. A densidade total dos esporos de fungos micorrízicos arbusculares sob o cupuaçu não é alterada pelo sistema de manejo ou pela época do ano, ao contrário do que ocorre sob a pupunha. Nessa cultura, a densidade de esporos foi maior sob sistema agroflorestal no período seco. A colonização micorrízica na pupunha apresenta dois padrões anatômicos, Paris e Arum, enquanto no cupuaçu ocorre o padrão Arum.The objective of this work was to evaluate the arbuscular mycorrhizal colonization in peach palm (Bactris gasipaes Kunth and cupuaçu (Theobroma grandiflorum (Willd ex Spring K. Schum, in agroforestry systems and monoculture in the Central Amazon region, and to identify anatomic characteristics of mycorrhizal colonization in these species. Soil and root samples were collected in the field, in the dry and rainy season. Mycorrhizal root colonization of cupuaçu and peach palm is affected by the management systems, with higher colonization rates in the monoculture system. Total spore density of the arbuscular mycorrhizal fungi under cupuaçu is not affected by management systems or season, but under peach palm this variation is season dependent. Mycorrhizal colonization of Arum and Paris types occur in peach palm, and only Arum type occurs in cupuaçu.

  19. Correlation of arbuscular mycorrhizal colonization with plant growth, nodulation, and shoot npk in legumes

    International Nuclear Information System (INIS)

    Javaid, A.; Anjum, T.; Shah, M.H.M.

    2007-01-01

    Correlation of arbuscular mycorrhizal colonization with different root and shoot growth, nodulation and shoot NPK parameters was studied in three legumes viz. Trifolium alexandrianum, Medicago polymorpha and Melilotus parviflora. The three test legume species showed different patterns of root and shoot growth, nodulation, mycorrhizal colonization and shoot N, P and K content. Different mycorrhizal structures viz. mycelium, arbuscules and vesicles showed different patters of correlation with different studied parameters. Mycelial infection showed an insignificantly positive correlation with root and shoot dry biomass and total root length. Maximum root length was however, negatively associated with mycelial infection. Both arbuscular and vesicular infections were negatively correlated with shoot dry biomass and different parameters of root growth. The association between arbuscular infection and maximum root length was significant. All the three mycorrhizal structures showed a positive correlation with number and biomass of nodules. The association between arbuscular infection and nodule number was significant. Mycelial infection was positively correlated with percentage and total shoot N and P. Similarly percentage N was also positively correlated with arbuscular and vesicular infections. By contrast, total shoot N showed a negative association with arbuscular as well as vesicular infections. Similarly both percentage and total shoot P were negatively correlated with arbuscular and vesicular infections. All the associations between mycorrhizal parameters and shoot K were negative except between vesicular infection and shoot %K. (author)

  20. [Discussion on appraisal methods and key technologies of arbuscular mycorrhizal fungi and medicinal plant symbiosis system].

    Science.gov (United States)

    Chen, Meilan; Guo, Lanping; Yang, Guang; Chen, Min; Yang, Li; Huang, Luqi

    2011-11-01

    Applications of arbuscular mycorrhizal fungi in research of medicinal plant cultivation are increased in recent years. Medicinal plants habitat is complicated and many inclusions are in root, however crop habitat is simple and few inclusions in root. So appraisal methods and key technologies about the symbiotic system of crop and arbuscular mycorrhizal fungi can't completely suitable for the symbiotic system of medicinal plants and arbuscular mycorrhizal fungi. This article discuss the appraisal methods and key technologies about the symbiotic system of medicinal plant and arbuscular mycorrhizal fungi from the isolation and identification of arbuscular mycorrhiza, and the appraisal of colonization intensity. This article provides guidance for application research of arbuscular mycorrhizal fungi in cultivation of medicinal plants.

  1. Carbon flow from plant to arbuscular mycorrhizal fungi is reduced under phosphorus fertilization

    Czech Academy of Sciences Publication Activity Database

    Konvalinková, Tereza; Püschel, David; Řezáčová, Veronika; Gryndlerová, Hana; Jansa, Jan

    2017-01-01

    Roč. 419, 1-2 (2017), s. 319-333 ISSN 0032-079X R&D Projects: GA MŠk(CZ) LK11224; GA ČR(CZ) GA14-19191S Institutional support: RVO:61388971 Keywords : Arbuscular mycorrhiza * Carbon allocation * Mycorrhizal cost Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 3.052, year: 2016

  2. Large-scale diversity patterns in spore communities of Arbuscular mycorrhizal fungi [Chapter 2

    Science.gov (United States)

    Javier Alvarez-Sanchez; Nancy C. Johnson; Anita Antoninka; V. Bala Chaudhary; Matthew K. Lau; Suzanne M. Owen; Patricia Gauadarrama; Silvia. Castillo

    2010-01-01

    Surprising little is known about the factors controlling Arbuscular Mycorrhizal (AM) fungal diversity and distribution patterns. A better understanding of these factors is necessary before mycorrhizas can be effectively managed for their benefits in ecosystem restoration and agriculture. The goal of this chapter is to examine the relationships between AM fungal...

  3. ARBUSCULAR MYCORRHIZAL FUNGI - AN ESSENTIAL TOOL TO SUSTAINABLE VINEYARD DEVELOPMENT: A REVIEW

    Directory of Open Access Journals (Sweden)

    Gheorghe Cristian Popescu

    2016-12-01

    Full Text Available Grapevine is one of the most important horticultural perennial crops grown in many countries from worldwide. In this paper, we review the global benefits of arbuscular mycorrhiza application for grapevine production and the impact of viticultural practices for these natural microorganisms to establish symbiotic associations with vine roots. This review aims to provide a brief overview of the status of and to outline the most important application and effects of AMF in viticulture in order to increase the sustainability of vineyards. Viticulture has to adapt to new challenges of pest and chemicals fertilizers management, climate change, global urbanization, land erosions, increasing droughts, world population growth and others factors that can affect the sustainability of viticultural production systems. One of eco-friendly approaches is to use the application of arbuscular mycorrhiza fungi (AMF. Response of grapevine to AMF application demonstrated a lot of benefits for viticultural ecosystems. Technologies on sustainable agriculture and conservation of ecosystems vineyards may consider arbuscular mycorrhiza fungi as biofertilizers. Arbuscular mycorrhiza fungi could be an effective tool for improving the agro-enviromental perfomance in viticultural farms.

  4. 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.

  5. Gibberellins Interfere with Symbiosis Signaling and Gene Expression and Alter Colonization by Arbuscular Mycorrhizal Fungi in Lotus japonicus1

    Science.gov (United States)

    Takeda, Naoya; Handa, Yoshihiro; Tsuzuki, Syusaku; Kojima, Mikiko; Sakakibara, Hitoshi; Kawaguchi, Masayoshi

    2015-01-01

    Arbuscular mycorrhiza is a mutualistic plant-fungus interaction that confers great advantages for plant growth. Arbuscular mycorrhizal (AM) fungi enter the host root and form symbiotic structures that facilitate nutrient supplies between the symbionts. The gibberellins (GAs) are phytohormones known to inhibit AM fungal infection. However, our transcriptome analysis and phytohormone quantification revealed GA accumulation in the roots of Lotus japonicus infected with AM fungi, suggesting that de novo GA synthesis plays a role in arbuscular mycorrhiza development. We found pleiotropic effects of GAs on the AM fungal infection. In particular, the morphology of AM fungal colonization was drastically altered by the status of GA signaling in the host root. Exogenous GA treatment inhibited AM hyphal entry into the host root and suppressed the expression of Reduced Arbuscular Mycorrhization1 (RAM1) and RAM2 homologs that function in hyphal entry and arbuscule formation. On the other hand, inhibition of GA biosynthesis or suppression of GA signaling also affected arbuscular mycorrhiza development in the host root. Low-GA conditions suppressed arbuscular mycorrhiza-induced subtilisin-like serine protease1 (SbtM1) expression that is required for AM fungal colonization and reduced hyphal branching in the host root. The reduced hyphal branching and SbtM1 expression caused by the inhibition of GA biosynthesis were recovered by GA treatment, supporting the theory that insufficient GA signaling causes the inhibitory effects on arbuscular mycorrhiza development. Most studies have focused on the negative role of GA signaling, whereas our study demonstrates that GA signaling also positively interacts with symbiotic responses and promotes AM colonization of the host root. PMID:25527715

  6. Gibberellins interfere with symbiosis signaling and gene expression and alter colonization by arbuscular mycorrhizal fungi in Lotus japonicus.

    Science.gov (United States)

    Takeda, Naoya; Handa, Yoshihiro; Tsuzuki, Syusaku; Kojima, Mikiko; Sakakibara, Hitoshi; Kawaguchi, Masayoshi

    2015-02-01

    Arbuscular mycorrhiza is a mutualistic plant-fungus interaction that confers great advantages for plant growth. Arbuscular mycorrhizal (AM) fungi enter the host root and form symbiotic structures that facilitate nutrient supplies between the symbionts. The gibberellins (GAs) are phytohormones known to inhibit AM fungal infection. However, our transcriptome analysis and phytohormone quantification revealed GA accumulation in the roots of Lotus japonicus infected with AM fungi, suggesting that de novo GA synthesis plays a role in arbuscular mycorrhiza development. We found pleiotropic effects of GAs on the AM fungal infection. In particular, the morphology of AM fungal colonization was drastically altered by the status of GA signaling in the host root. Exogenous GA treatment inhibited AM hyphal entry into the host root and suppressed the expression of Reduced Arbuscular Mycorrhization1 (RAM1) and RAM2 homologs that function in hyphal entry and arbuscule formation. On the other hand, inhibition of GA biosynthesis or suppression of GA signaling also affected arbuscular mycorrhiza development in the host root. Low-GA conditions suppressed arbuscular mycorrhiza-induced subtilisin-like serine protease1 (SbtM1) expression that is required for AM fungal colonization and reduced hyphal branching in the host root. The reduced hyphal branching and SbtM1 expression caused by the inhibition of GA biosynthesis were recovered by GA treatment, supporting the theory that insufficient GA signaling causes the inhibitory effects on arbuscular mycorrhiza development. Most studies have focused on the negative role of GA signaling, whereas our study demonstrates that GA signaling also positively interacts with symbiotic responses and promotes AM colonization of the host root. © 2015 American Society of Plant Biologists. All Rights Reserved.

  7. 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.

  8. Eficiência de fungos micorrízicos arbusculares isolados de solos sob diferentes sistemas de uso na região do Alto Solimões na Amazônia Effectiveness of arbuscular mycorrhiza fungal isolated from soils under different land use systems in the Alto Solimões river region in the Amazon

    Directory of Open Access Journals (Sweden)

    Gláucia Alves e Silva

    2009-09-01

    Full Text Available Os fungos micorrízicos arbusculares (FMAs são importantes componentes dos ecossistemas terrestres onde acredita-se desempenharem papel fundamental para a sustentabilidade destes. Estes fungos sofrem influência de diversos fatores antrópicos como o uso da terra, que modificam a estrutura e diversidade das comunidades podendo comprometer suas funções ecológicas. No presente estudo avaliou-se o comportamento de FMAs isolados de solos sob diferentes sistemas de uso (SUT. Fungos isolados de amostras de solo sob diferentes SUT foram testados em caupi [Vigna unguiculata (L. Walp] em condições controladas. Verificou-se que todos os cinqüenta e um fungos avaliados colonizaram o caupi, porém de modo muito diferenciado, tal como ocorreu para os efeitos destes na absorção de fósforo e crescimento da planta. A colonização variou de 1 a 68%, e os efeitos positivos no crescimento variaram de 33 a 148%, sendo mais comuns nos fungos isolados de pastagem e roça. O aumento nos teores de fósforo foi generalizado (95% dos fungos testados, no entanto, nem todos foram capazes de promover o crescimento do Caupi. Apenas 39% dos fungos foram considerados eficientes, sendo estes isolados de quase todos os SUT. Os tratamentos fúngicos de mais alta eficiência continham as espécies: A. foveata, Glomus sp.1, Acaulospora sp.1 e mistura dos dois primeiros mais E. infrequens e A. bireticulata-like. Os resultados indicam ampla diversidade de eficiência dos FMAs do Alto Solimões. Embora a eficiência não tenha relação direta com o SUT, a proporção de isolados eficientes variou com a origem de isolamento.Arbuscular mycorrhizal fungi (AMF are important components of terrestrial ecosystems where they are believed to play a fundamental role for their sustainability. These fungi are influenced by a number of anthropic factors such as, land use which modifies the structure and diversity of fungal communities and this may compromise their ecological functions

  9. Propágulos de fungos micorrízicos arbusculares em solos deficientes em fósforo sob diferentes usos, da região semi-arida no nordeste do Brasil Propagules of arbuscular mycorrhizae in p-deficient soils under different land uses, in semi-arid NE Brazil

    Directory of Open Access Journals (Sweden)

    Regina Lúcia Félix de Aguiar Lima

    2007-04-01

    Full Text Available A conversão de áreas de caatinga em agricultura e pecuária de subsistência é uma das características marcantes da região semi-árida do Nordeste do Brasil. O presente estudo investigou o efeito dessa conversão sobre os propágulos de fungos micorrízicos arbusculares (FMA em 10 locais diferentes, distribuídos nos Estados da Paraíba e de Pernambuco. Cada local consistiu de uma área de vegetação nativa (caatinga contígua com uma área cultivada, na mesma posição de encosta. Amostras de solo foram coletadas a intervalos de 20-30 m, nas profundidades de 0-7,5 e 7,5-15 cm (10 locais x 2 usos do solo x 2 profundidades com 4 pontos amostrais ao longo de uma transecção que cruzava as áreas contíguas. As raízes (The conversion of tropical dry forest into areas used for subsistence agriculture or livestock production is a common feature of the semi-arid region of NE Brazil. Our study looked into the effect of these land use changes on propagules of arbuscular mycorrhizal fungi (AMF at ten sites distributed in the states of Paraíba and Pernambuco. Each site consisted of an area under native vegetation (Dry-Forest adjacent to a cultivated area in the same slope position. Soil samples were taken at distance intervals of 20-30 m from two depths (0-7.5 and 7.5-15 cm along a transect crossing the adjacent areas (10 sites x 2 land uses x 2 depths x 4 sampling points. Roots (< 2 mm found in the soil samples (n = 160 were stained with trypan blue to assess the percentage of AMF colonization as well as the type of fungal structures. The AMF spores were separated from soil by wet sieving, incubated in iodonitrotetrazolium chloride (INT solution and counted; those stained with INT were considered viable. Soil samples were analyzed for resin-extractable P and total organic carbon (TOC. For data analysis, the 10 areas under dry forest were separated in two sub-groups: Undisturbed-Dry-Forest (UDF, n = 6 and Disturbed-Dry-Forest (DDF, n = 4, owing

  10. Potential contribution of arbuscular mycorrhiza to cadmium immobilisation in soil

    Czech Academy of Sciences Publication Activity Database

    Janoušková, Martina; Pavlíková, D.; Vosátka, Miroslav

    2006-01-01

    Roč. 65, č. 11 (2006), s. 1959-1965 ISSN 0045-6535 R&D Projects: GA ČR GA526/02/0293; GA AV ČR KSK6005114 Institutional research plan: CEZ:AV0Z60050516 Keywords : extraradical mycelium * heavy metals * rhizosphere Subject RIV: EF - Botanics Impact factor: 2.442, year: 2006

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

    African Journals Online (AJOL)

    ... heavy metals (Cd and Pb) uptake of Helianthus annuus L. from polluted soils. Cadmium sulfate (CdSO4.8H2O) and lead acetate ((CH3COO)2Pb.3H2O) were ... 0.05 mg Cd kg-1 and 0.23 mg Pb kg-1 were remediated with GM application.

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

    African Journals Online (AJOL)

    hope&shola

    2009-06-12

    Jun 12, 2009 ... performance and heavy metal uptake of Helianthus ... growth performance and heavy metals (Cd and Pb) uptake of Helianthus annuus L. from polluted soils. Cadmium sulfate ..... Phytoextraction of Toxic Metals: A review of.

  13. 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...

  14. L-System model for the growth of arbuscular mycorrhizal fungi, both within and outside of their host roots

    Czech Academy of Sciences Publication Activity Database

    Schnepf, A.; Leitner, D.; Schweiger, P.F.; Scholl, P.; Jansa, Jan

    2016-01-01

    Roč. 13, č. 117 (2016), s. 20160129 ISSN 1742-5689 R&D Projects: GA MŠk(CZ) LK11224 Institutional support: RVO:61388971 Keywords : L-system * arbuscular mycorrhiza * external hyphae Subject RIV: EE - Microbiology, Virology Impact factor: 3.579, year: 2016

  15. Arbuscular mycorrhizal symbiosis on serpentine soils: the effect of native fungal communities on different Knautia arvensis ecotypes

    Czech Academy of Sciences Publication Activity Database

    Doubková, Pavla; Suda, Jan; Sudová, Radka

    2011-01-01

    Roč. 345, 1-2 (2011), s. 325-338 ISSN 0032-079X R&D Projects: GA AV ČR KJB600050812 Institutional research plan: CEZ:AV0Z60050516 Keywords : arbuscular mycorrhiza * serpentine soils * edaphic stress Subject RIV: EF - Botanics Impact factor: 2.733, year: 2011

  16. 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.

  17. 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

    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...... 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......We conducted a field experiment to test the hypothesis that improved phosphorus nutrition occurs in maize plants with rapid arbuscular (AM) mycorrhizae development at early developmental stages and that this also is reflected in dry matter allocation and final yield. A split-split plot design...

  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. Root colonization of bait plants by indigenous arbuscular mycorrhizal fungal communities is not a suitable indicator of agricultural land-use legacy

    Czech Academy of Sciences Publication Activity Database

    Jansa, Jan; Řezáčová, Veronika; Šmilauer, P.; Oberholzer, H.-R.; Egli, S.

    2016-01-01

    Roč. 231, SEPTEMBER (2016), s. 310-319 ISSN 0167-8809 R&D Projects: GA ČR GAP504/12/1665; GA MŠk(CZ) LK11224 Institutional support: RVO:61388971 Keywords : Arbuscular mycorrhiza * Geography * Root colonization Subject RIV: EE - Microbiology, Virology Impact factor: 4.099, year: 2016

  20. Asymmetric response of root-associated fungal communities of an arbuscular mycorrhizal grass and an ectomycorrhizal tree to their coexistence in primary succession

    Czech Academy of Sciences Publication Activity Database

    Knoblochová, T.; Kohout, Petr; Püschel, D.; Doubková, P.; Frouz, J.; Cajthaml, T.; Kukla, J.; Vosátka, M.; Rydlová, J.

    2017-01-01

    Roč. 27, č. 8 (2017), s. 775-789 ISSN 0940-6360 R&D Projects: GA ČR GA13-10377S Institutional support: RVO:61388971 Keywords : Arbuscular mycorrhiza * Ectomycorrhiza * Root-associated fungal communities Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 3.047, year: 2016

  1. Rhizoglomus melanum, a new arbuscular mycorrhizal fungal species associated with submerged plants in freshwater lake Avsjøen in Norway

    Czech Academy of Sciences Publication Activity Database

    Sudová, Radka; Sýkorová, Zuzana; Rydlová, Jana; Čtvrtlíková, Martina; Oehl, F.

    2015-01-01

    Roč. 14, č. 3 (2015), s. 1-8, no.9 ISSN 1617-416X R&D Projects: GA ČR GAP504/10/0781 Institutional support: RVO:67985939 ; RVO:60077344 Keywords : arbuscular mycorrhiza * biodiversity * submerged plants Subject RIV: EF - Botanics; DA - Hydrology ; Limnology (BC-A) Impact factor: 1.572, year: 2015

  2. Comparison of arbuscular mycorrhizal fungal effects on the heavy metal uptake of a host and a non-host plant species in contact with extraradical mycelial network

    Czech Academy of Sciences Publication Activity Database

    Mnasri, M.; Janoušková, Martina; Rydlová, Jana; Abdelly, C.; Ghnaya, T.

    2017-01-01

    Roč. 171, MAR 2017 (2017), s. 476-484 ISSN 0045-6535 Institutional support: RVO:67985939 Keywords : arbuscular mycorrhiza * heavy metals * Sesuvium portulacastrum Subject RIV: EH - Ecology, Behaviour OBOR OECD: Ecology Impact factor: 4.208, year: 2016

  3. Inoculation effects on root-colonizing arbuscular mycorrhizal fungal communities spread beyond directly inoculated plants

    Czech Academy of Sciences Publication Activity Database

    Janoušková, Martina; Krak, Karol; Vosátka, Miroslav; Püschel, David; Štorchová, Helena

    2017-01-01

    Roč. 12, č. 7 (2017), s. 1-21, č. článku e0181525. E-ISSN 1932-6203 R&D Projects: GA MŠk(CZ) LH14285 Institutional support: RVO:67985939 ; RVO:61389030 Keywords : inoculation * arbuscular mycorrhiza * community Subject RIV: EH - Ecology, Behaviour; EH - Ecology, Behaviour (UEB-Q) OBOR OECD: Plant sciences, botany; Plant sciences, botany (UEB-Q) Impact factor: 2.806, year: 2016

  4. Fungal and plant gene expression in arbuscular mycorrhizal symbiosis.

    Science.gov (United States)

    Balestrini, Raffaella; Lanfranco, Luisa

    2006-11-01

    Arbuscular mycorrhizas (AMs) are a unique example of symbiosis between two eukaryotes, soil fungi and plants. This association induces important physiological changes in each partner that lead to reciprocal benefits, mainly in nutrient supply. The symbiosis results from modifications in plant and fungal cell organization caused by specific changes in gene expression. Recently, much effort has gone into studying these gene expression patterns to identify a wider spectrum of genes involved. We aim in this review to describe AM symbiosis in terms of current knowledge on plant and fungal gene expression profiles.

  5. 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

    Directory of Open Access Journals (Sweden)

    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

  6. Vesicular arbuscular mycorrhizal fungi prevalence and diversity in ...

    African Journals Online (AJOL)

    The prevalence and population levels of VAM fungi in a range of field soil environments in Zimbabwe were determined. The main VAM genera Acaulospora, Scutellospora, Gigaspora, Glomus, Sclerocystis and Entrophospora were represented in the study sites. The relative abundance was ...

  7. 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 ...

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

    African Journals Online (AJOL)

    USER

    2010-06-14

    Jun 14, 2010 ... 2Organic Farming Program, Vocational School of Bismil, Dicle University, .... area in the early morning (07:00 - 09:00) with 45 x 35 cm space in ..... Brazil. Robinson D, Fitter A (1999). The magnitude and control of carbon.

  9. Effects of Metal Phytoextraction Practices on the Indigenous Community of Arbuscular Mycorrhizal Fungi at a Metal-Contaminated Landfill

    Science.gov (United States)

    Pawlowska, Teresa E.; Chaney, Rufus L.; Chin, Mel; Charvat, Iris

    2000-01-01

    Phytoextraction involves use of plants to remove toxic metals from soil. We examined the effects of phytoextraction practices with three plant species (Silene vulgaris, Thlaspi caerulescens, and Zea mays) and a factorial variation of soil amendments (either an ammonium or nitrate source of nitrogen and the presence or absence of an elemental sulfur supplement) on arbuscular mycorrhizal (AM) fungi (Glomales, Zygomycetes) at a moderately metal-contaminated landfill located in St. Paul, Minn. Specifically, we tested whether the applied treatments affected the density of glomalean spores and AM root colonization in maize. Glomalean fungi from the landfill were grouped into two morphotypes characterized by either light-colored spores (LCS) or dark-colored spores (DCS). Dominant species of the LCS morphotype were Glomus mosseae and an unidentified Glomus sp., whereas the DCS morphotype was dominated by Glomus constrictum. The density of spores of the LCS morphotype from the phytoremediated area was lower than the density of these spores in the untreated landfill soil. Within the experimental area, spore density of the LCS morphotype in the rhizosphere of mycorrhizal maize was significantly higher than in rhizospheres of nonmycorrhizal S. vulgaris or T. caerulescens. Sulfur supplement increased vesicular root colonization in maize and exerted a negative effect on spore density in maize rhizosphere. We conclude that phytoextraction practices, e.g., the choice of plant species and soil amendments, may have a great impact on the quantity and species composition of glomalean propagules as well as on mycorrhiza functioning during long-term metal-remediation treatments. PMID:10831433

  10. Phosphorus and Nitrogen Regulate Arbuscular Mycorrhizal Symbiosis in Petunia hybrida

    Science.gov (United States)

    Nouri, Eva; Breuillin-Sessoms, Florence; Feller, Urs; Reinhardt, Didier

    2014-01-01

    Phosphorus and nitrogen are essential nutrient elements that are needed by plants in large amounts. The arbuscular mycorrhizal symbiosis between plants and soil fungi improves phosphorus and nitrogen acquisition under limiting conditions. On the other hand, these nutrients influence root colonization by mycorrhizal fungi and symbiotic functioning. This represents a feedback mechanism that allows plants to control the fungal symbiont depending on nutrient requirements and supply. Elevated phosphorus supply has previously been shown to exert strong inhibition of arbuscular mycorrhizal development. Here, we address to what extent inhibition by phosphorus is influenced by other nutritional pathways in the interaction between Petunia hybrida and R. irregularis. We show that phosphorus and nitrogen are the major nutritional determinants of the interaction. Interestingly, the symbiosis-promoting effect of nitrogen starvation dominantly overruled the suppressive effect of high phosphorus nutrition onto arbuscular mycorrhiza, suggesting that plants promote the symbiosis as long as they are limited by one of the two major nutrients. Our results also show that in a given pair of symbiotic partners (Petunia hybrida and R. irregularis), the entire range from mutually symbiotic to parasitic can be observed depending on the nutritional conditions. Taken together, these results reveal complex nutritional feedback mechanisms in the control of root colonization by arbuscular mycorrhizal fungi. PMID:24608923

  11. Phosphorus and nitrogen regulate arbuscular mycorrhizal symbiosis in Petunia hybrida.

    Science.gov (United States)

    Nouri, Eva; Breuillin-Sessoms, Florence; Feller, Urs; Reinhardt, Didier

    2014-01-01

    Phosphorus and nitrogen are essential nutrient elements that are needed by plants in large amounts. The arbuscular mycorrhizal symbiosis between plants and soil fungi improves phosphorus and nitrogen acquisition under limiting conditions. On the other hand, these nutrients influence root colonization by mycorrhizal fungi and symbiotic functioning. This represents a feedback mechanism that allows plants to control the fungal symbiont depending on nutrient requirements and supply. Elevated phosphorus supply has previously been shown to exert strong inhibition of arbuscular mycorrhizal development. Here, we address to what extent inhibition by phosphorus is influenced by other nutritional pathways in the interaction between Petunia hybrida and R. irregularis. We show that phosphorus and nitrogen are the major nutritional determinants of the interaction. Interestingly, the symbiosis-promoting effect of nitrogen starvation dominantly overruled the suppressive effect of high phosphorus nutrition onto arbuscular mycorrhiza, suggesting that plants promote the symbiosis as long as they are limited by one of the two major nutrients. Our results also show that in a given pair of symbiotic partners (Petunia hybrida and R. irregularis), the entire range from mutually symbiotic to parasitic can be observed depending on the nutritional conditions. Taken together, these results reveal complex nutritional feedback mechanisms in the control of root colonization by arbuscular mycorrhizal fungi.

  12. Interacción micorriza vesiculo-arbuscular, Rhizobium leguminosa en un oxisol de los Llanos Orientales de Colombia

    Directory of Open Access Journals (Sweden)

    Satizabal E. Jorge H.

    1987-03-01

    Full Text Available En los dos primeros trabajos (la y lb, se evaluó la interacción entre cepas seleccionadas de Rhizobium (apropiadas para la leguminosa forrajera tropical Centrosema macrocarpum y especies (Entrophospora colombiana, Acaulospora longula, Glomus manihotis de micorriza vesiculo arbuscular (MVA, en un suelo esterilizado, fijador de P. Los experimentos se diferenciaron por las fuentes de P utilizadas. Por su mayor producción de materia seca, absorción de minerales, nodulación y infección por MVA, se destacaron las plantas inoculadas con cuales quiera de las cepas de FIlizobiumy Glomus manihotis (Experimento la o Acaulospora longula (Experimento lb. En la tercera investigación (Experimento II, se evalúo en Centrosema la interacción MVA, Rhizobiumo N-químico (niveles equivalentes a 0, 30,55, 105,0 + Rhiz. y 30 + Rhiz. kg N ha-1 y dosis de P (0, 20, 40 y 80 kg ha-1. Es aconsejable aplicar pequeñas dosis (30 kg ha-1 de N al momento de la siembra e inocular con Rhizobium. Plantas inoculadas con MVA presentaron su óptimo crecimiento con 40 kg P ha-1. Dosis de 80 kg P ha-1 favoreció la eficiencia de la bacteria más no la del hongo.In the first two works (la and lb we evaluated the interation between selected stumps of Rhizobium (appropiate for the tropical forage legumes Centrosema macrocarpum and species (Entrophospora colombiana, Acaulospora longula, Glomus manihotis of vesicular-arbuscular mycorrhiza (MVA, in a sterelize soil fixer of P. The two experiments are different because we used different P sources. For the best production of dry matter, absorption of minerals, nodulation and infection for MVA; rebounded the plants with the inoculation with any of the Rhizobium´s stumps and Glomus manihotis (Experiment la of Acaulospora longula (Experiment lb. In the third investigation (Experiment II we evaluated in Centrosema the interaction MVA. Rhizobium and chemical N (levels equivalent to 0,30. 55, 105, O + Rhizobium and 30 + Rhizobium kg N ha

  13. Reaction and interaction of mycorrhizae and rhizosphere

    International Nuclear Information System (INIS)

    Kottke, I.

    1989-01-01

    Mycorrhizae of forest trees react and interact in a sensitive manner to environmental stress but have evolved adaption mechanism. Soil acidification causes no reduction of mycorrhizal frequency but shorter life span which is frequently compensated for by a higher production rate of mycorrhizae. Mycorrhizae of Norway spruce preferentially develop in soil pores. Nutrient availability probably relies more on the exchangeable ions at the surfaces of the pores than on the total ion exchange capacity. Additionally, organically bound compounds are mobilized by fungal hyphae and interaction on the rhizoplane. A lack of soil pores results in severe difficulties for Norway spruce to penetrate soil and to maintain mycorrhizal acticity. Water stress in the top soil causing a high percentage of dormant and dead mycorrhizae can be compensated for by a higher mycorrhizal production in deeper soil layers. At low nutrient availability in the mineral soil preferentially development of mycorrhizae is observed in the organic layer that may be regarded as an internal regulation mechanism, not as a toxic effect caused by Al in the mineral soil. Differentiated hyphal mantles protect mycorrhizae against water stress by impermeability and enhanced trehalose content and serve as storage and detoxification organs. There are indications of mycorrhizal types specially adapted to acidified soil conditions. (orig./vhe)

  14. Do ectomycorrhizal and arbuscular mycorrhizal temperate tree species systematically differ in root order-related fine root morphology and biomass?

    OpenAIRE

    Kubisch, Petra; Hertel, Dietrich; Leuschner, Christoph

    2015-01-01

    While most temperate broad-leaved tree species form ectomycorrhizal (EM) symbioses, a few species have arbuscular mycorrhizas (AM). It is not known whether EM and AM tree species differ systematically with respect to fine root morphology, fine root system size and root functioning. In a species-rich temperate mixed forest, we studied the fine root morphology and biomass of three EM and three AM tree species from the genera Acer, Carpinus, Fagus, Fraxinus, and Tilia searching for principal dif...

  15. Mycorrhiza

    Indian Academy of Sciences (India)

    the root surface and mineral uptake efficiency. Environmental .... The AM interactions are established further with the induc- tion of seven genes (SYM ... This eventually leads to the regulation of other genes and finally ... plants absorb copper and zinc by similar mechanisms. ... are essential for the survival of plant species.

  16. 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

    , is the transfer of phosphate (Pi) from the AM fungus to the plant, facilitated by plasma membrane-spanning Pi transporter proteins. The first mycorrhiza-specific plant Pi transporter to be identified, was StPT3 from potato [Nature 414 (2004) 462]. Here, we describe novel Pi transporters from the solanaceous...... species tomato, LePT4, and its orthologue StPT4 from potato, both being members of the Pht1 family of plant Pi transporters. Phylogenetic tree analysis demonstrates clustering of both LePT4 and StPT4 with the mycorrhiza-specific Pi transporter from Medicago truncatula [Plant Cell, 14 (2002) 2413] and rice......Solanaceous species are among the >200 000 plant species worldwide forming a mycorrhiza, that is, a root living in symbiosis with soil-borne arbuscular-mycorrhizal (AM) fungi. An important parameter of this symbiosis, which is vital for ecosystem productivity, agriculture, and horticulture...

  17. The water relations of mycorrhiza

    International Nuclear Information System (INIS)

    Leyton, L.

    1982-01-01

    The wettability of the surface of ectotrophic beech mycorrhiza roots which did not have any radiating hyphae, was much less than a non-mycorrhizal root epidermis. The mycorrhizal sheath has a lower permeability to the flow of water than the uninfected root. The mycorrhizal roots absorbed water more rapidly than non-mycorrhizal roots. Possible explanations for this unusual phenomenon were (1) the development of a lower water potential in water stressed mycorrhizal roots, (2) accummulation of absorbed water in the sheath and (3) a higher permeability of the sheath to incoming than outgoing water. A study with endotrophic red clover plants confirmed that infection markedly increased growth and P uptake. This was accompanied by a reduction in the root/shoot ratio. This could be explained by a faster recovery of stressed mycorrhizal plants when water was restored because they were more efficient in taking up water. Experiments with tritiated water (THO) were initiated but consistent values for conductivity were not obtained. (author)

  18. [Arbuscular mycorrhizal symbiosis influences the biological effects of nano-ZnO on maize].

    Science.gov (United States)

    Wang, Wei-Zhong; Wang, Fa-Yuan; Li, Shuai; Liu, Xue-Qin

    2014-08-01

    Engineered nanoparticles (ENPs) can be taken up and accumulated in plants, then enter human bodies via food chain, and thus cause potential health risk. Arbuscular mycorrhizal fungi form mutualistic symbioses with the majority of higher plants in terrestrial ecosystems, and potentially influence the biological effects of ENPs. The present greenhouse pot culture experiment studied the effects of inoculation with or without arbuscular mycorrhizal fungus Acaulospora mellea on growth and nutritional status of maize under different nano-ZnO levels (0, 500, 1 000, 2000 and 3 000 mg x kg(-1)) artificially added into soil. Results showed that with the increasing nano-ZnO levels in soil, mycorrhizal colonization rate and biomass of maize plants showed a decreasing trend, total root length, total surface area and total volume reduced, while Zn concentration and uptake in plants gradually increased, and P, N, K, Fe, and Cu uptake in shoots all decreased. Compared with the controls, arbuscular mycorrhizal inoculation improved the growth and P, N and K nutrition of maize, enhanced total root length, total surface area and total volume, and increased Zn allocation to roots when nano-ZnO was added. Our results firstly show that nano-ZnO in soil induces toxicity to arbuscular mycorrhizae, while arbuscular mycorrhizal inoculation can alleviate its toxicity and play a protective role in plants.

  19. 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.

  20. A Native Arbuscular Mycorrhizal Fungus, Acaulospora scrobiculata Stimulated Growth of Mongolian Crested Wheatgrass ( Agropyron cristatum (L. Gaertn.

    Directory of Open Access Journals (Sweden)

    Burenjargal Otgonsuren

    2010-12-01

    Full Text Available Agr opyron cristatum (L. Gaertn. (crested wheatgrass is an endemic plant species, which dominates most area of the Mongolian steppe and forest steppe. In the present study, spores of arbuscular mycorrhizal fungi in the rhizosphere soil of crested wheatgrass were isolated with wet- sieving/decanting methods, and the major species was identifi ed as Acaulospora scrobiculata Trappe. For arbuscular-mycorrhizal resynthesis, the spores of A. scrobiculata were propagated with corn pot-culture technique and inoculated onto the roots of crested wheatgrass seedlings. The inoculated crested wheatgrass seedlings exhibited vigor in growth, and examination of the root structure revealed the occurrence of arbuscules and vesicles in the cortical cells. These results demonstrated that A. scrobiculata could effectively form arbuscular mycorrhizas with crested wheatgrass and promote its growth, which can be used to restore Mongolian grassland.

  1. Imbalanced carbon-for-phosphorus exchange between European arbuscular mycorrhizal fungi and non-native Panicum grasses-A case of dysfunctional symbiosis

    Czech Academy of Sciences Publication Activity Database

    Řezáčová, Veronika; Slavíková, Renata; Konvalinková, Tereza; Hujslová, Martina; Gryndlerová, Hana; Gryndler, Milan; Püschel, David; Jansa, Jan

    2017-01-01

    Roč. 62, May 2017 (2017), s. 48-55 ISSN 0031-4056 R&D Projects: GA MŠk(CZ) LK11224; GA ČR(CZ) GA14-19191S Grant - others:AV ČR(CZ) Fellowship J. E. Purkyně Institutional support: RVO:61388971 Keywords : Arbuscular mycorrhiza * Panicum * Plant biomass Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 2.000, year: 2016

  2. Amazonian açai and food dyes for staining arbuscular- micorrhizal fungi

    Directory of Open Access Journals (Sweden)

    Aline Lourdes Martins Silva

    2015-12-01

    Full Text Available Arbuscular mycorrhizae microscopy requires differential staining of typical structures. Dyes employed, such as trypan blue, pose risks to health and environment. Alternative dyes such as pen ink and aniline have variable coloring efficiency. In this work, Brachiaria decumbens roots, discolored with caustic soda (NaOH, were stained with açai, annatto, saffron, trypan blue and pen inks. There were significant differences among dyes regarding stained mycorrhizal structures and pictures quality. Acai was considered the best alternative dye, with similar results to trypan blue.

  3. Growth and extracellular phosphatase activity of arbuscular mycorrhizal hyphae as influenced by soil organic matter

    DEFF Research Database (Denmark)

    Joner, E.J.; Jakobsen, I.

    1995-01-01

    Two experiments were set up to investigate the influence of soil organic matter on growth of arbuscular mycorrhizal (AM) hyphae and concurrent changes in soil inorganic P, organic P and phosphatase activity. A sandy loam soil was kept for 14 months under two regimes (outdoor where surplus...... additions. In soil with added clover alkaline phosphatase activity increased due to the presence of mycorrhizal hyphae. We suggest that mycorrhizas may influence the exudation of acid phosphatase by roots. Hyphae of G. invermaium did apparently not excrete extracellular phosphatases, but their presence may...

  4. 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.

  5. Role of Arbuscular Mycorrhizal Fungi on Iris

    Directory of Open Access Journals (Sweden)

    CHEN Yuan

    2014-06-01

    Full Text Available For efficiency using the amphibious plant iris to restore polluted water, the promoting effect of different arbuscular mycorrhiza fungi(AMFon iris was investigated, by monitoring the plant growth index, the physicochemical properties of the soil and the plant photosynthesis indexes. The result showed that the promoting effects of the AMF on the aboveground part and the underground part of the iris were based on different mechanism. For the underground part of the iris, the AMF stimulated its growth through the nutrient enrichment which was performed by the enormous hypha network. The nitrogen absorbing rate of the G. mosseae and the G. intraradices infected iris increased about 71.75% and 42.55%, and the phosphorous absorbing rate increased 8.36% and 9.5% separately. For the aboveground part of the iris, the AMF strengthened the conductance of the leaves’ stomas to control the balance between the net photosynthesis rate and the transpiration rate, so that the utilization rate of water resources was optimized, the metabolic rate was accelerated and the growth of the plant was promoted eventually. In this study, the promoting effect of the G. mosseae on the photosynthesis rate of the iris was significantly better than that of the G. intraradices(P<0.05.

  6. Efeito da mobilização do solo nas micorrizas arbusculares de cereais de Inverno Effects of soil management on arbuscular mycorrhizal fungi in autumn-sown crops

    Directory of Open Access Journals (Sweden)

    I. Brito

    2007-01-01

    sua capacidade para gerar novas colonizações no período cultural. Com o objectivo de avaliar a diversidade dos Glomeromycota presentes no campo de ensaios em estudo, sujeito aos dois tipos de mobilização do solo (SD e MT, foi usada a técnica de amplificação de sequências de rDNA destes fungos a partir de DNA total do solo. Esta técnica permite uma avaliação abrangente, evitando a morosidade e complexidade da abordagem clássica através de culturas armadilha. No total foram analisadas 87 sequencias, provenientes de solo perturbado e não perturbado, e encontrados 11 tipos ribosomais. Considerando as diferenças de frequência dos tipos ribosomais presentes em cada tipo de solo, os resultados parecem confirmar que os fungos micorrízicos arbusculares são diferencialmente susceptíveis à perturbação do solo, não só em termos de diversidade como ao nível da estrutura da comunidade.Soil tillage may markedly reduce the rate of arbuscular mycorrhiza (AM establishment by breaking up the living AM fungal mycelium in the soil. In no till or reduced till management, this mycelium can allow earlier AM formation. Work under field conditions in a Mediterranean climate clearly confirmed that wheat plants cultivated under no-till system had a 6 fold greater mycorrhizal colonization than those grown using a conventional tillage system. Pot experiments were initiated to determine the benefit of the timing of colonization on plants. Soil disturbance induced by tillage practices was simulated by passing the soil through a 4 mm sieve at the start of each successive period of 3 weeks plant growth cycles. After 4 cycles of plant growth (wheat, significant effects in all colonization parameters were detected. Arbuscular, vesicular and hyphal colonization were clearly higher in undisturbed soil. To gain a global overview of the diversity of Glomeromycota under the 2 cultivation systems in the experimental field, rDNA sequences from the fungi have been amplified

  7. Enhanced tomato disease resistance primed by arbuscular mycorrhizal fungus.

    Science.gov (United States)

    Song, Yuanyuan; Chen, Dongmei; Lu, Kai; Sun, Zhongxiang; Zeng, Rensen

    2015-01-01

    Roots of most terrestrial plants form symbiotic associations (mycorrhiza) with soil- borne arbuscular mycorrhizal fungi (AMF). Many studies show that mycorrhizal colonization enhances plant resistance against pathogenic fungi. However, the mechanism of mycorrhiza-induced disease resistance remains equivocal. In this study, we found that mycorrhizal inoculation with AMF Funneliformis mosseae significantly alleviated tomato (Solanum lycopersicum Mill.) early blight disease caused by Alternaria solani Sorauer. AMF pre-inoculation led to significant increases in activities of β-1,3-glucanase, chitinase, phenylalanine ammonia-lyase (PAL) and lipoxygenase (LOX) in tomato leaves upon pathogen inoculation. Mycorrhizal inoculation alone did not influence the transcripts of most genes tested. However, pathogen attack on AMF-inoculated plants provoked strong defense responses of three genes encoding pathogenesis-related proteins, PR1, PR2, and PR3, as well as defense-related genes LOX, AOC, and PAL, in tomato leaves. The induction of defense responses in AMF pre-inoculated plants was much higher and more rapid than that in un-inoculated plants in present of pathogen infection. Three tomato genotypes: a Castlemart wild-type (WT) plant, a jasmonate (JA) biosynthesis mutant (spr2), and a prosystemin-overexpressing 35S::PS plant were used to examine the role of the JA signaling pathway in AMF-primed disease defense. Pathogen infection on mycorrhizal 35S::PS plants led to higher induction of defense-related genes and enzymes relative to WT plants. However, pathogen infection did not induce these genes and enzymes in mycorrhizal spr2 mutant plants. Bioassays showed that 35S::PS plants were more resistant and spr2 plants were more susceptible to early blight compared with WT plants. Our finding indicates that mycorrhizal colonization enhances tomato resistance to early blight by priming systemic defense response, and the JA signaling pathway is essential for mycorrhiza

  8. Les mycorhizes à vésicules et arbuscules chez la vigne

    Directory of Open Access Journals (Sweden)

    Andrea Schubert

    1985-12-01

    Vesicular-arbuscular (VA mycorrhizae are widespread in vineyards. Their structures allow an improved phosphate nutrition and consequently an enhanced growth of the vine, specially in P-deficient soils. Experimental results obtained up to now show the interest in the use of artificially introduced VA mycorrhizae in some areas of viticultural practice.

  9. Gr and hp-1 tomato mutants unveil unprecedented interactions between arbuscular mycorrhizal symbiosis and fruit ripening.

    Science.gov (United States)

    Chialva, Matteo; Zouari, Inès; Salvioli, Alessandra; Novero, Mara; Vrebalov, Julia; Giovannoni, James J; Bonfante, Paola

    2016-07-01

    Systemic responses to an arbuscular mycorrhizal fungus reveal opposite phenological patterns in two tomato ripening mutants depending whether ethylene or light reception is involved. The availability of tomato ripening mutants has revealed many aspects of the genetics behind fleshy fruit ripening, plant hormones and light signal reception. Since previous analyses revealed that arbuscular mycorrhizal symbiosis influences tomato berry ripening, we wanted to test the hypothesis that an interplay might occur between root symbiosis and fruit ripening. With this aim, we screened seven tomato mutants affected in the ripening process for their responsiveness to the arbuscular mycorrhizal fungus Funneliformis mosseae. Following their phenological responses we selected two mutants for a deeper analysis: Green ripe (Gr), deficient in fruit ethylene perception and high-pigment-1 (hp-1), displaying enhanced light signal perception throughout the plant. We investigated the putative interactions between ripening processes, mycorrhizal establishment and systemic effects using biochemical and gene expression tools. Our experiments showed that both mutants, notwithstanding a normal mycorrhizal phenotype at root level, exhibit altered arbuscule functionality. Furthermore, in contrast to wild type, mycorrhization did not lead to a higher phosphate concentration in berries of both mutants. These results suggest that the mutations considered interfere with arbuscular mycorrhiza inducing systemic changes in plant phenology and fruits metabolism. We hypothesize a cross talk mechanism between AM and ripening processes that involves genes related to ethylene and light signaling.

  10. The arbuscular mycorrhizal fungus Rhizophagus irregularis differentially regulates the copper response of two maize cultivars differing in copper tolerance.

    Science.gov (United States)

    Merlos, Miguel A; Zitka, Ondrej; Vojtech, Adam; Azcón-Aguilar, Concepción; Ferrol, Nuria

    2016-12-01

    Arbuscular mycorrhiza can increase plant tolerance to heavy metals. The effects of arbuscular mycorrhiza on plant metal tolerance vary depending on the fungal and plant species involved. Here, we report the effect of the arbuscular mycorrhizal fungus Rhizophagus irregularis on the physiological and biochemical responses to Cu of two maize genotypes differing in Cu tolerance, the Cu-sensitive cv. Orense and the Cu-tolerant cv. Oropesa. Development of the symbiosis confers an increased Cu tolerance to cv. Orense. Root and shoot Cu concentrations were lower in mycorrhizal than in non-mycorrhizal plants of both cultivars. Shoot lipid peroxidation increased with soil Cu content only in non-mycorrhizal plants of the Cu-sensitive cultivar. Root lipid peroxidation increased with soil Cu content, except in mycorrhizal plants grown at 250mg Cu kg -1 soil. In shoots of mycorrhizal plants of both cultivars, superoxide dismutase, ascorbate peroxidase, catalase and glutathione reductase activities were not affected by soil Cu content. In Cu-supplemented soils, total phytochelatin content increased in shoots of mycorrhizal cv. Orense but decreased in cv. Oropesa. Overall, these data suggest that the increased Cu tolerance of mycorrhizal plants of cv. Orense could be due to an increased induction of shoot phytochelatin biosynthesis by the symbiosis in this cultivar. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  11. Current treatment of vesicular lithiasis

    International Nuclear Information System (INIS)

    Garcia Rodriguez, Oscar

    2010-01-01

    Surgical treatment of vesicular lithiasis has changed in past years. The addition of the new techniques in daily medical practice not always is immediate. Reasons relative to when to operate a patient presenting with gall bladder calculi are argued and documenting how this procedure is mainly reserved for symptomatic patients where pain is considered as a symptom par excellence. Also, it is exposed how this change has been faced. (author)

  12. EFFECT OF DIESEL AND BIODIESEL ON THE GROWTH OF Brachiaria decumbens INOCULATED WITH ARBUSCULAR MYCORRHIZAL FUNGI

    Directory of Open Access Journals (Sweden)

    Dora Trejo

    2013-12-01

    Full Text Available Arbuscular mycorrhizal fungi have been found to be associated with plants useful in soil phytoremediation. The aim of this study was to compare the effects of diesel and biodiesel in soil and sand on the growth of Brachiaria decumbens inoculated with mycorrhizae. Two experiments were carried out: one experiment in soil and another in sand. A two-level- factorial design with three factors was used (one on sterile and another on non-sterile soil, with and without mycorrhizae; and one with diesel and another with biodiesel. In sand, a two-factor design with two levels was used (with and without mycorrhizae and with diesel and biodiesel, both with three replications. NOVADIESEL, biodiesel and PEMEX diesel were use as contaminants, both at 7%. The fresh and dry weight of the plants and percentage of mycorrhizal colonization, were assessed 30 days after planting. In soil, biodiesel was more toxic and reduced the fresh and dry weights of plants, especially in non-sterile soil. Biodiesel yielded greater mycorrhizal colonization values that doubled those of the control. In sand, diesel was found to reduce three times the fresh and dry weights of plants, compared to the biodiesel. In sand diesel presented high values of mycorrhizal colonization in comparison with biodiesel.  Plants inoculated with mycorrhizal fungi exhibited better development than non-inoculated plants, even in the presence of contaminants.

  13. Arbuscular mycorrhizal fungi mediated uptake of 137Cs in leek and ryegrass

    International Nuclear Information System (INIS)

    Rosen, Klas; Weiliang, Zhong; Maertensson, Anna

    2005-01-01

    In a first experiment of soil contaminated with 137 Cs, inoculation with a mixture of arbuscular mycorrhizae enhanced the uptake of 137 Cs by leek under greenhouse conditions, while no effect on the uptake by ryegrass was observed. The mycorrhizal infection frequency in leek was independent of whether the 137 Cs-contaminated soil was inoculated with mycorrhizal spores or not. The lack of mycorrhizae-mediated uptake of 137 Cs in ryegrass could be due to the high root density, which was about four times that of leek, or due to a less well functioning mycorrhizal symbiosis than of leek. In a second experiment, ryegrass was grown for a period of four cuts. Additions of fungi enhanced 137 Cs uptake of all harvests, improved dry weight production in the first cut, and also improved the mycorrhizal infection frequencies in the roots. No differences were obtained between the two fungal inoculums investigated with respect to biomass production or 137 Cs uptake, but root colonization differed. We conclude that, under certain circumstances, mycorrhizae affect plant uptake of 137 Cs. There may be a potential for selecting fungal strains that stimulate 137 Cs accumulation in crops. The use of ryegrass seems to be rather ineffective for remediation of 137 Cs-contaminated soil

  14. Effect of arbuscular mycorrhizal (AM) fungi on 137Cs uptake by plants grown on different soils

    International Nuclear Information System (INIS)

    Vinichuk, M.; Mårtensson, A.; Ericsson, T.; Rosén, K.

    2013-01-01

    The potential use of mycorrhiza as a bioremediation agent for soils contaminated by radiocesium was evaluated in a greenhouse experiment. The uptake of 137 Cs by cucumber, perennial ryegrass, and sunflower after inoculation with a commercial arbuscular mycorrhizal (AM) product in soils contaminated with 137 Cs was investigated, with non-mycorrhizal quinoa included as a “reference” plant. The effect of cucumber and ryegrass inoculation with AM fungi on 137 Cs uptake was inconsistent. The effect of AM fungi was most pronounced in sunflower: both plant biomass and 137 Cs uptake increased on loamy sand and loamy soils. The total 137 Cs activity accumulated within AM host sunflower on loamy sand and loamy soils was 2.4 and 3.2-fold higher than in non-inoculated plants. Although the enhanced uptake of 137 Cs by quinoa plants on loamy soil inoculated by the AM fungi was observed, the infection of the fungi to the plants was not confirmed. - Highlights: ► Effect of soil inoculation on 137 Cs uptake by crops was studied in greenhouse. ► 137 Cs uptake by inoculated sunflower plants was most pronounced. ► The higher 137 Cs uptake by inoculated sunflower due to presence of mycorrhiza. ► Studies suggest potential for use of mycorrhiza on contaminated sites.

  15. Arbuscular mycorrhizal fungi mediated uptake of {sup 137}Cs in leek and ryegrass

    Energy Technology Data Exchange (ETDEWEB)

    Rosen, Klas; Weiliang, Zhong; Maertensson, Anna [Department of Soil Sciences, Swedish University of Agricultural Sciences P.O. Box 7014, SE-750 07 Uppsala (Sweden)

    2005-02-15

    In a first experiment of soil contaminated with {sup 137}Cs, inoculation with a mixture of arbuscular mycorrhizae enhanced the uptake of {sup 137}Cs by leek under greenhouse conditions, while no effect on the uptake by ryegrass was observed. The mycorrhizal infection frequency in leek was independent of whether the {sup 137}Cs-contaminated soil was inoculated with mycorrhizal spores or not. The lack of mycorrhizae-mediated uptake of {sup 137}Cs in ryegrass could be due to the high root density, which was about four times that of leek, or due to a less well functioning mycorrhizal symbiosis than of leek. In a second experiment, ryegrass was grown for a period of four cuts. Additions of fungi enhanced {sup 137}Cs uptake of all harvests, improved dry weight production in the first cut, and also improved the mycorrhizal infection frequencies in the roots. No differences were obtained between the two fungal inoculums investigated with respect to biomass production or {sup 137}Cs uptake, but root colonization differed. We conclude that, under certain circumstances, mycorrhizae affect plant uptake of {sup 137}Cs. There may be a potential for selecting fungal strains that stimulate {sup 137}Cs accumulation in crops. The use of ryegrass seems to be rather ineffective for remediation of {sup 137}Cs-contaminated soil.

  16. 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...

  17. Transfer of N and P from intact or decomposing roots of pea to barley interconnected by an arbuscular mycorrhizal fungus

    DEFF Research Database (Denmark)

    Johansen, A.; Jensen, E.S.

    1996-01-01

    of growth. In half of the containers, the donor-plant shoot was removed 42 d after the start of labelling and the roots were left in the soil to decompose. The reverse transfer of N and P, from barley donor to pea receiver plants was also measured to allow calculation of the net transfer through hyphae...... by G, intraradices. The results for P transfer followed the same patterns as was observed for N, although in smaller proportions. The results indicate that arbuscular mycorrhizas may play a significant role in the flow of N and P between two plants interconnected by hyphae, when the root system of one...

  18. 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

  19. 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

  20. Transmission and pathogenesis of vesicular stomatitis viruses

    Science.gov (United States)

    Vesicular Stomatitis (VS) is caused by the Vesicular Stomatitis Virus (VSV), a negative single stranded RNA arthropod-borne virus member of the Family Rhabdoviridae. The virion is composed of the host derived plasma membrane, the envelope, and an internal ribonucleoprotein core. The envelope contain...

  1. Characterization of Tuber borchii and Arbutus unedo mycorrhizas.

    Science.gov (United States)

    Lancellotti, Enrico; Iotti, Mirco; Zambonelli, Alessandra; Franceschini, Antonio

    2014-08-01

    For the first time, arbutoid mycorrhizas established between Tuber borchii and Arbutus unedo were described. Analyzed mycorrhizas were from one T. borchii natural truffle ground, dominated by Pinus pinea, as well as synthesized in greenhouse conditions. A. unedo mycorrhizas presented some typical characteristics of ectomycorrhizas of T. borchii. However, as in arbutoid mycorrhizas, ramification was cruciform and intracellular colonization in epidermal cells was present. The ability of T. borchii to form ectomycorrhizas with A. unedo opens up the possibility to also use this fruit plant for truffle cultivation. This represents an important economic opportunity in Mediterranean areas by combining both the cultivation of precious truffles and the production of edible fruits which are used fresh or in food delicacies.

  2. 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

  3. Tolerance of Mycorrhiza infected pistachio (Pistacia vera L.) seedling to drought stress under glasshouse conditions.

    Science.gov (United States)

    Abbaspour, H; Saeidi-Sar, S; Afshari, H; Abdel-Wahhab, M A

    2012-05-01

    The influence of Glomus etunicatum colonization on plant growth and drought tolerance of 3-month-old Pistacia vera seedlings in potted culture was studied in two different water treatments. The arbuscular mycorrhiza (AM) inoculation and plant growth (including plant shoot and root weight, leaf area, and total chlorophyll) were higher for well-watered than for water-stressed plants. The growth of AM-treated seedlings was higher than non-AM-treatment regardless of water status. P, K, Zn and Cu contents in AM-treated shoots were greater than those in non-AM shoots under well-watered conditions and drought stress. N and Ca content were higher under drought stress, while AM symbiosis did not affect the Mg content. The contents of soluble sugars, proteins, flavonoid and proline were higher in mycorrhizal than non-mycorrhizal-treated plants under the whole water regime. AM colonization increased the activities of peroxidase enzyme in treatments, but did not affect the catalase activity in shoots and roots under well-watered conditions and drought stress. We conclude that AM colonization improved the drought tolerance of P. vera seedlings by increasing the accumulation of osmotic adjustment compounds, nutritional and antioxidant enzyme activity. It appears that AM formation enhanced the drought tolerance of pistachio plants, which increased host biomass and plant growth. Copyright © 2012 Elsevier GmbH. All rights reserved.

  4. 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.

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

    Czech Academy of Sciences Publication Activity Database

    Rydlová, Jana; Püschel, David; Dostálková, M.; Janoušková, Martina; Frouz, J.

    2016-01-01

    Roč. 26, č. 7 (2016), s. 757-767 ISSN 0940-6360 R&D Projects: GA ČR GA13-10377S Institutional support: RVO:67985939 Keywords : chronosequence * mycorrhizal growth response * spoil banks Subject RIV: EF - Botanics Impact factor: 3.047, year: 2016

  6. 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

    - compartment petri dishes and three ammonium levels were supplied to the compartment containing the extraradical mycelium (ERM), but no roots. Time courses of specific enzyme activity were obtained for glutamine synthetase, argininosuccinate synthetase, arginase, and urease in the ERM and AM roots. 15 NH 4 1...... was used to follow the dynamics of nitrogen incorporation into and turnover of Arg. Both the absence of external nitrogen and the presence of L- norvaline, an inhibitor of Arg synthesis, prevented the synthesis of Arg in the ERM and resulted in decreased activity of arginase and urease in the AM root...

  7. Arbuscular mycorrhiza decreases cadmium phytoextraction by transgenic tobacco with inserted metallothionein

    Czech Academy of Sciences Publication Activity Database

    Janoušková, Martina; Pavlíková, D.; Macek, Tomáš; Vosátka, Miroslav

    2005-01-01

    Roč. 272, - (2005), s. 29-40 ISSN 0032-079X R&D Projects: GA ČR(CZ) GA526/02/0293 Institutional research plan: CEZ:AV0Z60050516 Keywords : CUP1 gene * heavy metals * soil microflora Subject RIV: EF - Botanics Impact factor: 1.703, year: 2005

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

    Czech Academy of Sciences Publication Activity Database

    Rydlová, Jana; Sýkorová, Zuzana; Slavíková, Renata; Turis, P.

    2015-01-01

    Roč. 25, č. 8 (2015), s. 599-609 ISSN 0940-6360 Institutional support: RVO:67985939 ; RVO:61388971 Keywords : wild cyclamens * Septoglomus constrictum * growth response Subject RIV: EF - Botanics; EE - Microbiology, Virology (MBU-M) Impact factor: 3.252, year: 2015

  9. 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...

  10. Multiple Exocytotic Markers Accumulate at the Sites of Perifungal Membrane Biogenesis in Arbuscular Mycorrhizas

    Czech Academy of Sciences Publication Activity Database

    Genre, A.; Ivanov, S.; Fendrych, Matyáš; Faccio, A.; Žárský, Viktor; Bisseling, T.; Bonfante, P.

    2012-01-01

    Roč. 53, č. 1 (2012), s. 244-255 ISSN 0032-0781 R&D Projects: GA ČR(CZ) GAP305/11/1629 Institutional research plan: CEZ:AV0Z50380511 Keywords : Daucus carota * Exocytosis * Medicago truncatula Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.134, year: 2012

  11. 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

    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...

  12. Lights Off for Arbuscular Mycorrhiza: On Its Symbiotic Functioning under Light Deprivation

    Czech Academy of Sciences Publication Activity Database

    Konvalinková, Tereza; Jansa, Jan

    2016-01-01

    Roč. 7, JUNE (2016), s. 782 ISSN 1664-462X R&D Projects: GA ČR(CZ) GA14-19191S; GA MŠk(CZ) LK11224 Institutional support: RVO:61388971 Keywords : mycorrhizal symbiosis * costs and benefits * light intensity Subject RIV: EF - Botanics Impact factor: 4.298, year: 2016

  13. 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.

  14. 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

  15. 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

  16. Radiocaesium in fruitbodies and mycorrhizae in ectomycorrhizal fungi

    International Nuclear Information System (INIS)

    Nikolova, Ivanka; Johanson, K.J.; Dahlberg, Anders

    1997-01-01

    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 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 137 Cs within fruitbodies was studied by collecting fruitbodies growing in clusters. Between 13 and 64% of the mean ground 137 Cs deposition of the cluster area (400 or 625 cm 2 ) was found in the fruitbodies. This indicates that there might be an important fungal redistribution of 137 Cs in the forest floor during the production of fruitbodies. The distribution of 137 Cs within the fruitbodies was heterogenous. For example in Cortinarious armillatus, the 137 Cs level in the cap was 2.7 times higher compared to in the stripe. (Author)

  17. 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).

  18. Diversity of arbuscular mycorrhizal fungi in grassland spontaneously developed on area polluted by a fertilizer plant

    International Nuclear Information System (INIS)

    Renker, C.; Blanke, V.; Buscot, F.

    2005-01-01

    Mycorrhizal colonization and diversity of arbuscular mycorrhizal fungi (AMF) were analyzed in a calcareous grassland with residual phosphate contamination 10 years after the closure of a pollutant fertilizer plant in Thuringia (Germany). AMF were detected in 21 of 22 plant species analyzed. Mean mycorrhization levels reached up to 74.5% root length colonized. AMF diversity was analyzed based on 104 sequences of the internal transcribed spacer (ITS) of the ribosomal DNA. Phylogenetic analyses revealed a total of 6 species all belonging to the genus Glomus. There was no overlap between species detected as active mycorrhizas on roots (2 taxa) or as spores (4 taxa). Compared to the regional context, the diversity of AMF at our field site was reduced, which may reflect a residual disturbance effect. However, none of the detected species was exclusive to the polluted site as they are commonly found in the region. - Almost all plant species were mycorrhizal

  19. Effect of arbuscular mycorrhizal fungi and pesticides on Cynara cardunculus growth

    Directory of Open Access Journals (Sweden)

    M. MARIN

    2008-12-01

    Full Text Available Wild cardoon (Cynara cardunculus L. is a promising crop for biomass production. A nursery trial was conducted to investigate the effectiveness of mycorrhizal inoculation on the biomass yield of wild cardoon seedlings and the effect of the pesticides fosetyl-Al, folpet and propamocarb, as fungicides, and isofenphos, phoxim and oxamyl, as insecticides, on cardoon plant growth and the mycorrhization. The arbuscular mycorrhizal (AM fungi inocula were: commercial inoculum with Glomus mosseae spores, and an inoculum of a Glomus sp. strain (AMF-i isolated locally. Mycorrhizal inoculation with either inoculum increased cardoon shoot biomass compared to non-inoculated control plants. The pesticide applications had a neutral or positive effect on cardoon seedling growth. However, the AM fungi colonisation did not decrease except for plants colonised by G. mosseae and treated with the insecticides isofenphos and oxamyl. Thus, the mycorrhiza can survive to pesticide concentrations employed in commercial nursery, and enhance cardoon plant productivity.

  20. Implication of evolution and diversity in arbuscular and ectomycorrhizal symbioses.

    Science.gov (United States)

    Buscot, François

    2015-01-01

    Being highly sensitive to ecological variations, symbiotic associations should inherently have a limited occurrence in nature. To circumvent this sensitivity and reach their universal distribution, symbioses used three strategies during their evolution, which all generated high biodiversity levels: (i) specialization to a specific environment, (ii) protection of one partner via its internalization into the other, (iii) frequent partner exchange. Mycorrhizal associations follow the 3rd strategy, but also present traits of internalization. As most ancient type, arbuscular mycorrhiza (AM) formed by a monophyletic fungal group with reduced species richness did constantly support the mineral nutrition of terrestrial plants and enabled their ecological radiation and actual biodiversity level. In contrast ectomycorrhiza (EM) evolved later and independently within different taxa of fungi able to degrade complex organic plant residues, and the diversity levels of EM fungal and tree partners are balanced. Despite their different origins and diversity levels, AM and EM fungi display similar patterns of diversity dynamics in ecosystems. At each time or succession interval, a few dominant and many rare fungi are recruited by plants roots from a wide reservoir of propagules. However, the dominant fungal partners are frequently replaced in relation to changes in the vegetation or ecological conditions. While the initial establishment of AM and EM fungal communities corresponds to a neutral recruitment, their further succession is rather driven by niche differentiation dynamics. Copyright © 2014 The Authors. Published by Elsevier GmbH.. All rights reserved.

  1. Arbuscular-mycorrhizal networks inhibit Eucalyptus tetrodonta seedlings in rain forest soil microcosms.

    Directory of Open Access Journals (Sweden)

    David P Janos

    Full Text Available Eucalyptus tetrodonta, a co-dominant tree species of tropical, northern Australian savannas, does not invade adjacent monsoon rain forest unless the forest is burnt intensely. Such facilitation by fire of seedling establishment is known as the "ashbed effect." Because the ashbed effect might involve disruption of common mycorrhizal networks, we hypothesized that in the absence of fire, intact rain forest arbuscular mycorrhizal (AM networks inhibit E. tetrodonta seedlings. Although arbuscular mycorrhizas predominate in the rain forest, common tree species of the northern Australian savannas (including adult E. tetrodonta host ectomycorrhizas. To test our hypothesis, we grew E. tetrodonta and Ceiba pentandra (an AM-responsive species used to confirm treatments separately in microcosms of ambient or methyl-bromide fumigated rain forest soil with or without severing potential mycorrhizal fungus connections to an AM nurse plant, Litsea glutinosa. As expected, C. pentandra formed mycorrhizas in all treatments but had the most root colonization and grew fastest in ambient soil. E. tetrodonta seedlings also formed AM in all treatments, but severing hyphae in fumigated soil produced the least colonization and the best growth. Three of ten E. tetrodonta seedlings in ambient soil with intact network hyphae died. Because foliar chlorosis was symptomatic of iron deficiency, after 130 days we began to fertilize half the E. tetrodonta seedlings in ambient soil with an iron solution. Iron fertilization completely remedied chlorosis and stimulated leaf growth. Our microcosm results suggest that in intact rain forest, common AM networks mediate belowground competition and AM fungi may exacerbate iron deficiency, thereby enhancing resistance to E. tetrodonta invasion. Common AM networks-previously unrecognized as contributors to the ashbed effect-probably help to maintain the rain forest-savanna boundary.

  2. Effect of mycorrhiza and phosphorus content in nutrient solution on the yield and nutritional status of tomato plants grown on rockwool or coconut coir

    Directory of Open Access Journals (Sweden)

    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.

  3. Mycorrhizal infection, phosphorus uptake, and phenology in Ranunculus adoneus: implications for the functioning of mycorrhizae in alpine systems.

    Science.gov (United States)

    Mullen, R B; Schmidt, S K

    1993-05-01

    Phosphorus levels, phenology of roots and shoots, and development of vesicular arbuscular mycorrhizal (VAM) fungi were monitored for two years in natural populations of the perennial alpine herb, Ranunculus adoneus. The purpose of this study was to understand how phosphorus uptake relates to the phenology of R. adoneus and to ascertain whether arbusculus, fungal structures used for nutrient transfer, were present when maximum phosphorus accumulation was occurring. Arbuscules were only present for a few weeks during the growing season of R. adoneus and their presence corresponded with increased phosphorus accumulation in both the roots and shoots of R. adoneus. In addition, phosphorus accumulation and peaks in mycorrhizal development occurred well after plant reproduction and most plant growth had occurred. The late season accumulation of phosphorus by mycorrhizal roots of R. adoneus is stored for use during early season growth and flowering the following spring. In this way R. adoneus can flower before soils thaw and root or mycorrhizal nutrient uptake can occur.

  4. 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 ...

  5. 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

  6. Symbiotic interaction of endophytic bacteria with arbuscular mycorrhizal fungi and its antagonistic effect on Ganoderma boninense.

    Science.gov (United States)

    Sundram, Shamala; Meon, Sariah; Seman, Idris Abu; Othman, Radziah

    2011-08-01

    Endophytic bacteria (Pseudomonas aeruginosa UPMP3 and Burkholderia cepacia UMPB3), isolated from within roots of oil palm (Elaeis guineensis Jacq.) were tested for their presymbiotic effects on two arbuscular mcorrhizal fungi, Glomus intraradices UT126 and Glomus clarum BR152B). These endophytic bacteria were also tested for antagonistic effects on Ganoderma boninense PER 71, a white wood rot fungal pathogen that causes a serious disease in oil palm. Spore germination and hyphal length of each arbuscular mycorrhizal fungal (AMF) pairing with endophytic bacteria was found to be significantly higher than spores plated in the absence of bacteria. Scanning electron microscopy (SEM) showed that the endophytic bacteria were scattered, resting or embedded on the surface hyaline layer or on the degraded walls of AMF spores, possibly feeding on the outer hyaline spore wall. The antagonistic effect of the endophytic bacteria was expressed as severe morphological abnormalities in the hyphal structures of G. boninense PER 71. The effects of the endophytic bacteria on G. boninense PER 71 hyphal structures were observed clearly under SEM. Severe inter-twisting, distortion, lysis and shriveling of the hyphal structures were observed. This study found that the effect of endophytic bacteria on G. intraradices UT126 and G. clarum BR152B resembled that of a mycorrhiza helper bacteria (MHB) association because the association significantly promoted AMF spore germination and hyphal length. However, the endophytic bacteria were extremely damaging to G. boninense PER 71.

  7. Genetic diversity patterns of arbuscular mycorrhizal fungi associated with the mycoheterotroph Arachnitis uniflora Phil. (Corsiaceae).

    Science.gov (United States)

    Renny, Mauricio; Acosta, M Cristina; Cofré, Noelia; Domínguez, Laura S; Bidartondo, Martin I; Sérsic, Alicia N

    2017-06-01

    Arachnitis uniflora is a mycoheterotrophic plant that exploits arbuscular mycorrhizal fungi of neighbouring plants. We tested A. uniflora 's specificity towards fungi across its large latitudinal range, as well as the role of historical events and current environmental, geographical and altitudinal variables on fungal genetic diversity. Arachnitis uniflora mycorrhizas were sampled at 25 sites. Fungal phylogenetic relationships were reconstructed, genetic diversity was calculated and the main divergent lineages were dated. Phylogeographical analysis was performed with the main fungal clade. Fungal diversity correlations with environmental factors were investigated. Glomeraceae fungi dominated, with a main clade that likely originated in the Upper Cretaceous and diversified in the Miocene. Two other arbuscular mycorrhizal fungal families not previously known to be targeted by A. uniflora were detected rarely and appear to be facultative associations. High genetic diversity, found in Bolivia and both northern and southern Patagonia, was correlated with temperature, rainfall and soil features. Fungal genetic diversity and its distribution can be explained by the ancient evolutionary history of the target fungi and by micro-scale environmental conditions with a geographical mosaic pattern. © The Author 2017. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  8. Insights on the Impact of Arbuscular Mycorrhizal Symbiosis on Tomato Tolerance to Water Stress1[OPEN

    Science.gov (United States)

    Siciliano, Ilenia

    2016-01-01

    Arbuscular mycorrhizal (AM) fungi, which form symbioses with the roots of the most important crop species, are usually considered biofertilizers, whose exploitation could represent a promising avenue for the development in the future of a more sustainable next-generation agriculture. The best understood function in symbiosis is an improvement in plant mineral nutrient acquisition, as exchange for carbon compounds derived from the photosynthetic process: this can enhance host growth and tolerance to environmental stresses, such as water stress (WS). However, physiological and molecular mechanisms occurring in arbuscular mycorrhiza-colonized plants and directly involved in the mitigation of WS effects need to be further investigated. The main goal of this work is to verify the potential impact of AM symbiosis on the plant response to WS. To this aim, the effect of two AM fungi (Funneliformis mosseae and Rhizophagus intraradices) on tomato (Solanum lycopersicum) under the WS condition was studied. A combined approach, involving ecophysiological, morphometric, biochemical, and molecular analyses, has been used to highlight the mechanisms involved in plant response to WS during AM symbiosis. Gene expression analyses focused on a set of target genes putatively involved in the plant response to drought, and in parallel, we considered the expression changes induced by the imposed stress on a group of fungal genes playing a key role in the water-transport process. Taken together, the results show that AM symbiosis positively affects the tolerance to WS in tomato, with a different plant response depending on the AM fungi species involved. PMID:27208301

  9. Expression of phenazine biosynthetic genes during the arbuscular mycorrhizal symbiosis of Glomus intraradices

    Directory of Open Access Journals (Sweden)

    Dionicia Gloria León-Martínez

    2012-06-01

    Full Text Available To explore the molecular mechanisms that prevail during the establishment of the arbuscular mycorrhiza symbiosis involving the genus Glomus, we transcriptionally analysed spores of Glomus intraradices BE3 during early hyphal growth. Among 458 transcripts initially identified as being expressed at presymbiotic stages, 20% of sequences had homology to previously characterized eukaryotic genes, 30% were homologous to fungal coding sequences, and 9% showed homology to previously characterized bacterial genes. Among them, GintPbr1a encodes a homolog to Phenazine Biosynthesis Regulator (Pbr of Burkholderia cenocepacia, an pleiotropic regulatory protein that activates phenazine production through transcriptional activation of the protein D isochorismatase biosynthetic enzyme phzD (Ramos et al., 2010. Whereas GintPbr1a is expressed during the presymbiotic phase, the G. intraradices BE3 homolog of phzD (BGintphzD is transcriptionally active at the time of the establishment of the arbuscular mycorrhizal symbiosis. DNA from isolated bacterial cultures found in spores of G. intraradices BE3 confirmed that both BGintPbr1a and BGintphzD are present in the genome of its potential endosymbionts. Taken together, our results indicate that spores of G. intraradices BE3 express bacterial phenazine biosynthetic genes at the onset of the fungal-plant symbiotic interaction.

  10. Response of Sesbania grandiflora to Inoculation of Soil with Vesicular-Arbuscular Mycorrhizal Fungi.

    Science.gov (United States)

    Habte, M; Aziz, T

    1985-09-01

    A greenhouse experiment was conducted to determine the influence of two tropical isolates of Glomus fasciculatum and Glomus mosseae on the nutrient uptake and growth of Sesbania grandiflora. Inoculation of sterile soil with the fungi significantly improved growth and nutrient uptake by S. grandiflora, but the response of the legume was markedly better when the soil was inoculated with G. fasciculatum than when it was inoculated with G. mosseae. Nutrient uptake and growth of S. grandiflora in nonsterile soil was also significantly stimulated by inoculation, but the legume did not respond differently to the two endophytes under this condition.

  11. 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 CFA-soil admixtures at 7.5% and 15% (w/w) significantly (p 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 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 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.

  12. Nursery inoculation with the arbuscular mycorrhizal fungus Glomus viscosum and its effect on the growth and physiology of hybrid artichoke seedlings

    Directory of Open Access Journals (Sweden)

    Angela Campanelli

    2011-09-01

    Full Text Available Most nurseries operating in Italy adopt high technologies and produce transplants that well suit and satisfy the grower’s need to produce high value crops. Mycorrhizas are discussed as a tool for improving and developing plant production in the nursery. Much research has been carried out on mycorrhizal symbiosis and we now know more about the symbiontic relationship between fungi and host plants. Plants receive numerous benefits from this symbiosis which are more macroscopic the earlier in the ontogenetic cycle this symbiosis is established. Therefore, it appears that the most effective period in which the inoculum should be made corresponds to the in-nursery growing stage. The earlier the plant is inoculated, the more evident the effect will be. In this study, several aspects related to the physiological foundations of arbuscular mycorrhiza in artichoke plants are presented. The main goal was to study the effects of mycorrhiza on the growth and physiological parameters of three hybrids of artichokes growing in the nursery. The experimental 3¥2 design included two treatments (with or without arbuscular mycorrhizal fungi and three hybrids of artichokes marketed by Nunhems (Opal F1, Madrigal F1, Concerto F1. Mycorrhizal plants have greater shoot length, leaf area, shoot and root fresh and dry mass, and root density. This also corresponded with increased photosynthetic rates and stomatal conductance of mycorrhizal plants. Mycorrhizal colonization improves relative water content and increases proline concentration in vegetal tissue. Inoculation produced the most beneficial effect on hybrid Madrigal F1 and on hybrid Opal F1; the best mycorrhizal affinity was enhanced when compared to hybrid Concerto F1. The results showed that mycorrhizal symbiosis stimulated the growth of inoculated seedlings providing a qualitatively good propagation material.

  13. Nursery inoculation with the arbuscular mycorrhizal fungus Glomus viscosum and its effect on the growth and physiology of hybrid artichoke seedlings

    Directory of Open Access Journals (Sweden)

    Angela Campanelli

    2011-07-01

    Full Text Available Most nurseries operating in Italy adopt high technologies and produce transplants that well suit and satisfy the grower’s need to produce high value crops. Mycorrhizas are discussed as a tool for improving and developing plant production in the nursery. Much research has been carried out on mycorrhizal symbiosis and we now know more about the symbiontic relationship between fungi and host plants. Plants receive numerous benefits from this symbiosis which are more macroscopic the earlier in the ontogenetic cycle this symbiosis is established. Therefore, it appears that the most effective period in which the inoculum should be made corresponds to the in-nursery growing stage. The earlier the plant is inoculated, the more evident the effect will be. In this study, several aspects related to the physiological foundations of arbuscular mycorrhiza in artichoke plants are presented. The main goal was to study the effects of mycorrhiza on the growth and physiological parameters of three hybrids of artichokes growing in the nursery. The experimental 3¥2 design included two treatments (with or without arbuscular mycorrhizal fungi and three hybrids of artichokes marketed by Nunhems (Opal F1, Madrigal F1, Concerto F1. Mycorrhizal plants have greater shoot length, leaf area, shoot and root fresh and dry mass, and root density. This also corresponded with increased photosynthetic rates and stomatal conductance of mycorrhizal plants. Mycorrhizal colonization improves relative water content and increases proline concentration in vegetal tissue. Inoculation produced the most beneficial effect on hybrid Madrigal F1 and on hybrid Opal F1; the best mycorrhizal affinity was enhanced when compared to hybrid Concerto F1. The results showed that mycorrhizal symbiosis stimulated the growth of inoculated seedlings providing a qualitatively good propagation material.

  14. Regulation of vesicular trafficking by Parkinson's disease-associated genes

    Directory of Open Access Journals (Sweden)

    Tsuyoshi Inoshita

    2015-10-01

    Full Text Available The regulatory mechanisms that control intracellular vesicular trafficking play important roles in cellular function and viability. Neurons have specific vesicular trafficking systems for synaptic vesicle formation, release and recycling. Synaptic vesicular trafficking impairments induce neuronal dysfunction and physiological and behavioral disorders. Parkinson's disease (PD is an age-dependent neurodegenerative disorder characterized by dopamine depletion and loss of dopamine neurons in the midbrain. The molecular mechanism responsible for the neurodegeneration that occurs during PD is still not understood; however, recent functional analyses of familial PD causative genes suggest that a number of PD causative genes regulate intracellular vesicular trafficking, including synaptic vesicular dynamics. This review focuses on recent insights regarding the functions of PD causative genes, their relationship with vesicular trafficking and how mutations associated with PD affect vesicular dynamics and neuronal survival.

  15. 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

    Directory of Open Access Journals (Sweden)

    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

  16. Effect of phosphate and the arbuscular mycorrhizal fungus Glomus intraradices on disease severity of root rot of peas ( Pisum sativum ) caused by Aphanomyces euteiches

    DEFF Research Database (Denmark)

    Bødker, Lars; Kjøller, Rasmus; Rosendahl, Søren

    1998-01-01

    The effects of inorganic phosphate levels and the presence of arbuscular mycorrhiza on disease severity of Aphanomyces euteiches in pea roots were studied. Disease severity on roots and epicotyl as well as the oospore number within infected root tissue were correlated with the phosphorus (P) level...... to measure the activity of the pathogen in roots. The enzyme activity increased with disease severity and disease incidence, except in plants supplemented with P at the highest level, where a peak in activity was seen 12 days after inoculation with the pathogen, followed by a decrease in activity...

  17. Arbuscular mycorrhizal fungi in phytoremediation of contaminated areas by trace elements: mechanisms and major benefits of their applications.

    Science.gov (United States)

    Cabral, Lucélia; Soares, Claúdio Roberto Fonsêca Sousa; Giachini, Admir José; Siqueira, José Oswaldo

    2015-11-01

    In recent decades, the concentration of trace elements has increased in soil and water, mainly by industrialization and urbanization. Recovery of contaminated areas is generally complex. In that respect, microorganisms can be of vital importance by making significant contributions towards the establishment of plants and the stabilization of impacted areas. Among the available strategies for environmental recovery, bioremediation and phytoremediation outstand. Arbuscular mycorrhizal fungi (AMF) are considered the most important type of mycorrhizae for phytoremediation. AMF have broad occurrence in contaminated soils, and evidences suggest they improve plant tolerance to excess of certain trace elements. In this review, the use of AMF in phytoremediation and mechanisms involved in their trace element tolerance are discussed. Additionally, we present some techniques used to study the retention of trace elements by AMF, as well as a summary of studies showing major benefits of AMF for phytoremediation.

  18. Influence of silver and titanium nanoparticles on arbuscular mycorrhizal colonization and accumulation of radiocaesium in Helianthus annuus

    International Nuclear Information System (INIS)

    Dubchak, S.; Ogar, A.; Mietelski, J. W.; Turnau, K.

    2010-01-01

    The influence of arbuscular mycorrhizal fungus on 1 34Cs uptake by Helianthus annuus was studied in a pilot study under growth chamber conditions. Mycorrhizal plants took up five times more 1 34Cs (up to 250,000 Bq kg - 1 dry weight) than non mycorrhizal plants. Silver and titanium nanoparticles, supplied into the surface soil layer decreased both the mycorrhizal colonization and Cs uptake by mycorrhizal plants. The application of activated carbon attenuated the effect of nanoparticles and increased 1 34Cs uptake in the presence of mycorrhizal fungi (up to 400,000 Bq kg - 1 dry weight). The results underline the possible application of phyto remediation techniques based on mycorrhizas assisted plants in decontamination of both radionuclides and nanoparticles. (Author) 27 refs.

  19. Model of reversible vesicular transport with exclusion

    International Nuclear Information System (INIS)

    Bressloff, Paul C; Karamched, Bhargav R

    2016-01-01

    A major question in neurobiology concerns the mechanics behind the motor-driven transport and delivery of vesicles to synaptic targets along the axon of a neuron. Experimental evidence suggests that the distribution of vesicles along the axon is relatively uniform and that vesicular delivery to synapses is reversible. A recent modeling study has made explicit the crucial role that reversibility in vesicular delivery to synapses plays in achieving uniformity in vesicle distribution, so called synaptic democracy (Bressloff et al 2015 Phys. Rev. Lett. 114 168101). In this paper we generalize the previous model by accounting for exclusion effects (hard-core repulsion) that may occur between molecular motor-cargo complexes (particles) moving along the same microtubule track. The resulting model takes the form of an exclusion process with four internal states, which distinguish between motile and stationary particles, and whether or not a particle is carrying vesicles. By applying a mean field approximation and an adiabatic approximation we reduce the system of ODEs describing the evolution of occupation numbers of the sites on a 1D lattice to a system of hydrodynamic equations in the continuum limit. We find that reversibility in vesicular delivery allows for synaptic democracy even in the presence of exclusion effects, although exclusion does exacerbate nonuniform distributions of vesicles in an axon when compared with a model without exclusion. We also uncover the relationship between our model and other models of exclusion processes with internal states. (paper)

  20. Vesicular stomatitis forecasting based on Google Trends.

    Science.gov (United States)

    Wang, JianYing; Zhang, Tong; Lu, Yi; Zhou, GuangYa; Chen, Qin; Niu, Bing

    2018-01-01

    Vesicular stomatitis (VS) is an important viral disease of livestock. The main feature of VS is irregular blisters that occur on the lips, tongue, oral mucosa, hoof crown and nipple. Humans can also be infected with vesicular stomatitis and develop meningitis. This study analyses 2014 American VS outbreaks in order to accurately predict vesicular stomatitis outbreak trends. American VS outbreaks data were collected from OIE. The data for VS keywords were obtained by inputting 24 disease-related keywords into Google Trends. After calculating the Pearson and Spearman correlation coefficients, it was found that there was a relationship between outbreaks and keywords derived from Google Trends. Finally, the predicted model was constructed based on qualitative classification and quantitative regression. For the regression model, the Pearson correlation coefficients between the predicted outbreaks and actual outbreaks are 0.953 and 0.948, respectively. For the qualitative classification model, we constructed five classification predictive models and chose the best classification predictive model as the result. The results showed, SN (sensitivity), SP (specificity) and ACC (prediction accuracy) values of the best classification predictive model are 78.52%,72.5% and 77.14%, respectively. This study applied Google search data to construct a qualitative classification model and a quantitative regression model. The results show that the method is effective and that these two models obtain more accurate forecast.

  1. Vesicular stomatitis forecasting based on Google Trends

    Science.gov (United States)

    Lu, Yi; Zhou, GuangYa; Chen, Qin

    2018-01-01

    Background Vesicular stomatitis (VS) is an important viral disease of livestock. The main feature of VS is irregular blisters that occur on the lips, tongue, oral mucosa, hoof crown and nipple. Humans can also be infected with vesicular stomatitis and develop meningitis. This study analyses 2014 American VS outbreaks in order to accurately predict vesicular stomatitis outbreak trends. Methods American VS outbreaks data were collected from OIE. The data for VS keywords were obtained by inputting 24 disease-related keywords into Google Trends. After calculating the Pearson and Spearman correlation coefficients, it was found that there was a relationship between outbreaks and keywords derived from Google Trends. Finally, the predicted model was constructed based on qualitative classification and quantitative regression. Results For the regression model, the Pearson correlation coefficients between the predicted outbreaks and actual outbreaks are 0.953 and 0.948, respectively. For the qualitative classification model, we constructed five classification predictive models and chose the best classification predictive model as the result. The results showed, SN (sensitivity), SP (specificity) and ACC (prediction accuracy) values of the best classification predictive model are 78.52%,72.5% and 77.14%, respectively. Conclusion This study applied Google search data to construct a qualitative classification model and a quantitative regression model. The results show that the method is effective and that these two models obtain more accurate forecast. PMID:29385198

  2. Vesicular stomatitis forecasting based on Google Trends.

    Directory of Open Access Journals (Sweden)

    JianYing Wang

    Full Text Available Vesicular stomatitis (VS is an important viral disease of livestock. The main feature of VS is irregular blisters that occur on the lips, tongue, oral mucosa, hoof crown and nipple. Humans can also be infected with vesicular stomatitis and develop meningitis. This study analyses 2014 American VS outbreaks in order to accurately predict vesicular stomatitis outbreak trends.American VS outbreaks data were collected from OIE. The data for VS keywords were obtained by inputting 24 disease-related keywords into Google Trends. After calculating the Pearson and Spearman correlation coefficients, it was found that there was a relationship between outbreaks and keywords derived from Google Trends. Finally, the predicted model was constructed based on qualitative classification and quantitative regression.For the regression model, the Pearson correlation coefficients between the predicted outbreaks and actual outbreaks are 0.953 and 0.948, respectively. For the qualitative classification model, we constructed five classification predictive models and chose the best classification predictive model as the result. The results showed, SN (sensitivity, SP (specificity and ACC (prediction accuracy values of the best classification predictive model are 78.52%,72.5% and 77.14%, respectively.This study applied Google search data to construct a qualitative classification model and a quantitative regression model. The results show that the method is effective and that these two models obtain more accurate forecast.

  3. The impact of arbuscular mycorrhizal fungi in mitigating salt-induced adverse effects in sweet basil (Ocimum basilicum L.).

    Science.gov (United States)

    Elhindi, Khalid M; El-Din, Ahmed Sharaf; Elgorban, Abdallah M

    2017-01-01

    Salinity is one of the serious abiotic stresses adversely affecting the majority of arable lands worldwide, limiting the crop productivity of most of the economically important crops. Sweet basil ( Osmium basilicum ) plants were grown in a non-saline soil (EC = 0.64 dS m -1 ), in low saline soil (EC = 5 dS m -1 ), and in a high saline soil (EC = 10 dS m -1 ). There were differences between arbuscular mycorrhizal ( Glomus deserticola ) colonized plants (+AMF) and non-colonized plants (-AMF). Mycorrhiza mitigated the reduction of K, P and Ca uptake due to salinity. The balance between K/Na and between Ca/Na was improved in +AMF plants. Growth enhancement by mycorrhiza was independent from plant phosphorus content under high salinity levels. Different growth parameters, salt stress tolerance and accumulation of proline content were investigated, these results showed that the use of mycorrhizal inoculum (AMF) was able to enhance the productivity of sweet basil plants under salinity conditions. Mycorrhizal inoculation significantly increased chlorophyll content and water use efficiency under salinity stress. The sweet basil plants appeared to have high dependency on AMF which improved plant growth, photosynthetic efficiency, gas exchange and water use efficiency under salinity stress. In this study, there was evidence that colonization with AMF can alleviate the detrimental salinity stress influence on the growth and productivity of sweet basil plants.

  4. The impact of arbuscular mycorrhizal fungi in mitigating salt-induced adverse effects in sweet basil (Ocimum basilicum L.

    Directory of Open Access Journals (Sweden)

    Khalid M. Elhindi

    2017-01-01

    Full Text Available Salinity is one of the serious abiotic stresses adversely affecting the majority of arable lands worldwide, limiting the crop productivity of most of the economically important crops. Sweet basil (Osmium basilicum plants were grown in a non-saline soil (EC = 0.64 dS m−1, in low saline soil (EC = 5 dS m−1, and in a high saline soil (EC = 10 dS m−1. There were differences between arbuscular mycorrhizal (Glomus deserticola colonized plants (+AMF and non-colonized plants (−AMF. Mycorrhiza mitigated the reduction of K, P and Ca uptake due to salinity. The balance between K/Na and between Ca/Na was improved in +AMF plants. Growth enhancement by mycorrhiza was independent from plant phosphorus content under high salinity levels. Different growth parameters, salt stress tolerance and accumulation of proline content were investigated, these results showed that the use of mycorrhizal inoculum (AMF was able to enhance the productivity of sweet basil plants under salinity conditions. Mycorrhizal inoculation significantly increased chlorophyll content and water use efficiency under salinity stress. The sweet basil plants appeared to have high dependency on AMF which improved plant growth, photosynthetic efficiency, gas exchange and water use efficiency under salinity stress. In this study, there was evidence that colonization with AMF can alleviate the detrimental salinity stress influence on the growth and productivity of sweet basil plants.

  5. Efeito de fungos micorrízicos arbusculares no desenvolvimento do abacateiro Effect of arbuscular mycorrhizal fungi on growth of avocado

    Directory of Open Access Journals (Sweden)

    Samar Velho da Silveira

    2002-11-01

    Full Text Available O objetivo deste trabalho foi determinar a influência da inoculação de seis espécies de fungos micorrízicos arbusculares (FMA (Glomus clarum, G. etunicatum, G. manihotis, Acaulospora scrobiculata, Scutellospora heterogama e Gigaspora margarita sobre o desenvolvimento vegetativo de mudas de abacateiro (Persea sp., nas fases de porta-enxerto, de muda enxertada e de muda no pomar. A influência dos FMA em abacateiros foi variável conforme a espécie do endófito em estudo. As espécies S. heterogama, A. scrobiculata, G. etunicatum e G. clarum colonizaram mais intensamente o sistema radicular dos abacateiros, promovendo melhor desenvolvimento vegetativo das plantas, na fase de porta-enxerto, ao longo do período de produção da muda e após o transplante para pomar.The objective of this work was to evaluate the influence of six arbuscular mycorrhizal fungi (AMF (Glomus clarum, G. etunicatum, G. manihotis, Acaulospora scrobiculata, Scutellospora heterogama and Gigaspora margarita on the vegetative growth, of grafted avocado plants (Persea sp., in the rootstocks phase, grafted plant and after transplant to the orchard. The influence of AMF in avocado plants varyed according to the endophytic mycorrhiza species under study. The species S. heterogama, A. scrobiculata, G. etunicatum and G. clarum were more effective in root colonization, promoting better vegetative growth of plants on the rootstock phase, during the plant production period and after the transplanting to the orchard.

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

    African Journals Online (AJOL)

    Field experiments were carried out on an alley-cropping farm in Ajibode village, near Ibadan where cassava alley-cropped with three hedgerow trees (Leucaena leucocephala, Gliricidia sepium and Senna (Syn Cassia) siamea), and sole planted cassava (all in three replicates) were arranged with arbuscular mycorrhizal ...

  7. The plasma membrane proteome of Medicago truncatula roots as modified by arbuscular mycorrhizal symbiosis.

    Science.gov (United States)

    Aloui, Achref; Recorbet, Ghislaine; Lemaître-Guillier, Christelle; Mounier, Arnaud; Balliau, Thierry; Zivy, Michel; Wipf, Daniel; Dumas-Gaudot, Eliane

    2018-01-01

    In arbuscular mycorrhizal (AM) roots, the plasma membrane (PM) of the host plant is involved in all developmental stages of the symbiotic interaction, from initial recognition to intracellular accommodation of intra-radical hyphae and arbuscules. Although the role of the PM as the agent for cellular morphogenesis and nutrient exchange is especially accentuated in endosymbiosis, very little is known regarding the PM protein composition of mycorrhizal roots. To obtain a global overview at the proteome level of the host PM proteins as modified by symbiosis, we performed a comparative protein profiling of PM fractions from Medicago truncatula roots either inoculated or not with the AM fungus Rhizophagus irregularis. PM proteins were isolated from root microsomes using an optimized discontinuous sucrose gradient; their subsequent analysis by liquid chromatography followed by mass spectrometry (MS) identified 674 proteins. Cross-species sequence homology searches combined with MS-based quantification clearly confirmed enrichment in PM-associated proteins and depletion of major microsomal contaminants. Changes in protein amounts between the PM proteomes of mycorrhizal and non-mycorrhizal roots were monitored further by spectral counting. This workflow identified a set of 82 mycorrhiza-responsive proteins that provided insights into the plant PM response to mycorrhizal symbiosis. Among them, the association of one third of the mycorrhiza-responsive proteins with detergent-resistant membranes pointed at partitioning to PM microdomains. The PM-associated proteins responsive to mycorrhization also supported host plant control of sugar uptake to limit fungal colonization, and lipid turnover events in the PM fraction of symbiotic roots. Because of the depletion upon symbiosis of proteins mediating the replacement of phospholipids by phosphorus-free lipids in the plasmalemma, we propose a role of phosphate nutrition in the PM composition of mycorrhizal roots.

  8. Does responsiveness to arbuscular mycorrhizal fungi depend on plant invasive status?

    Science.gov (United States)

    Reinhart, Kurt O; Lekberg, Ylva; Klironomos, John; Maherali, Hafiz

    2017-08-01

    Differences in the direction and degree to which invasive alien and native plants are influenced by mycorrhizal associations could indicate a general mechanism of plant invasion, but whether or not such differences exist is unclear. Here, we tested whether mycorrhizal responsiveness varies by plant invasive status while controlling for phylogenetic relatedness among plants with two large grassland datasets. Mycorrhizal responsiveness was measured for 68 taxa from the Northern Plains, and data for 95 taxa from the Central Plains were included. Nineteen percent of taxa from the Northern Plains had greater total biomass with mycorrhizas while 61% of taxa from the Central Plains responded positively. For the Northern Plains taxa, measurable effects often depended on the response variable (i.e., total biomass, shoot biomass, and root mass ratio) suggesting varied resource allocation strategies when roots are colonized by arbuscular mycorrhizal fungi. In both datasets, invasive status was nonrandomly distributed on the phylogeny. Invasive taxa were mainly from two clades, that is, Poaceae and Asteraceae families. In contrast, mycorrhizal responsiveness was randomly distributed over the phylogeny for taxa from the Northern Plains, but nonrandomly distributed for taxa from the Central Plains. After controlling for phylogenetic similarity, we found no evidence that invasive taxa responded differently to mycorrhizas than other taxa. Although it is possible that mycorrhizal responsiveness contributes to invasiveness in particular species, we find no evidence that invasiveness in general is associated with the degree of mycorrhizal responsiveness. However, mycorrhizal responsiveness among species grown under common conditions was highly variable, and more work is needed to determine the causes of this variation.

  9. Two putative-aquaporin genes are differentially expressed during arbuscular mycorrhizal symbiosis in Lotus japonicus

    Directory of Open Access Journals (Sweden)

    Giovannetti Marco

    2012-10-01

    Full Text Available Abstract Background Arbuscular mycorrhizas (AM are widespread symbioses that provide great advantages to the plant, improving its nutritional status and allowing the fungus to complete its life cycle. Nevertheless, molecular mechanisms that lead to the development of AM symbiosis are not yet fully deciphered. Here, we have focused on two putative aquaporin genes, LjNIP1 and LjXIP1, which resulted to be upregulated in a transcriptomic analysis performed on mycorrhizal roots of Lotus japonicus. Results A phylogenetic analysis has shown that the two putative aquaporins belong to different functional families: NIPs and XIPs. Transcriptomic experiments have shown the independence of their expression from their nutritional status but also a close correlation with mycorrhizal and rhizobial interaction. Further transcript quantification has revealed a good correlation between the expression of one of them, LjNIP1, and LjPT4, the phosphate transporter which is considered a marker gene for mycorrhizal functionality. By using laser microdissection, we have demonstrated that one of the two genes, LjNIP1, is expressed exclusively in arbuscule-containing cells. LjNIP1, in agreement with its putative role as an aquaporin, is capable of transferring water when expressed in yeast protoplasts. Confocal analysis have demonstrated that eGFP-LjNIP1, under its endogenous promoter, accumulates in the inner membrane system of arbusculated cells. Conclusions Overall, the results have shown different functionality and expression specificity of two mycorrhiza-inducible aquaporins in L. japonicus. One of them, LjNIP1 can be considered a novel molecular marker of mycorrhizal status at different developmental stages of the arbuscule. At the same time, LjXIP1 results to be the first XIP family aquaporin to be transcriptionally regulated during symbiosis.

  10. Pancreatitis aguda grave asociada a gangrena vesicular

    OpenAIRE

    Arroyo-Sánchez, Abel S; Aguirre-Mejía, Rosa Y; Echenique-Martínez, Sergio E

    2014-01-01

    Se presenta el caso un paciente diabético que desarrolló un cuadro de pancreatitis aguda grave asociada a gangrena vesicular, en el que se evaluó la aplicabilidad de los criterios de clasificación y manejo de la hoja de ruta para pancreatitis aguda, así mismo se proponen algunos tópicos que pudieran ser investigados a futuro We present a diabetic patient who developed severe acute pancreatitis associated to gallbladder gangrene, in this case we assessed the applicability of classification ...

  11. Arbuscular mycorrhizal fungi associations of vascular plants confined to river valleys: towards understanding the river corridor plant distribution.

    Science.gov (United States)

    Nobis, Agnieszka; Błaszkowski, Janusz; Zubek, Szymon

    2015-01-01

    The group of river corridor plants (RCP) includes vascular plant species which grow mainly or exclusively in the valleys of large rivers. Despite the long recognized fact that some plant species display a corridor-like distribution pattern in Central Europe, there is still no exhaustive explanation of the mechanisms generating this peculiar distribution. The main goal of this study was therefore to investigate whether arbuscular mycorrhizal fungi (AMF) and fungal root endophytes influence the RCP distribution. Arbuscular mycorrhizae (AM) were observed in 19 out of 33 studied RCP. Dark septate endophytes (DSE) and Olpidium spp. were recorded with low abundance in 15 and 10 plant species, respectively. The spores of AMF were found only in 32% of trap cultures established from the soils collected in the river corridor habitats. In total, six widespread AMF species were identified. Because the percentage of non-mycorrhizal species in the group of RCP is significant and the sites in river corridors are characterized by low AMF species diversity, RCP can be outcompeted outside river valleys by the widespread species that are able to benefit from AM associations in more stable plant-AMF communities in non-river habitats.

  12. The impact of domestication and crop improvement on arbuscular mycorrhizal symbiosis in cereals: insights from genetics and genomics.

    Science.gov (United States)

    Sawers, Ruairidh J H; Ramírez-Flores, M Rosario; Olalde-Portugal, Víctor; Paszkowski, Uta

    2018-04-15

    Contents Summary I. Introduction II. Recruitment of plant metabolites and hormones as signals in AM symbiosis III. Phytohormones are regulators of AM symbiosis and targets of plant breeding IV. Variations in host response to AM symbiosis V. Outlook Acknowledgements References SUMMARY: Cereals (rice, maize, wheat, sorghum and the millets) provide over 50% of the world's caloric intake, a value that rises to > 80% in developing countries. Since domestication, cereals have been under artificial selection, largely directed towards higher yield. Throughout this process, cereals have maintained their capacity to interact with arbuscular mycorrhizal (AM) fungi, beneficial symbionts that associate with the roots of most terrestrial plants. It has been hypothesized that the shift from the wild to cultivation, and above all the last c. 50 years of intensive breeding for high-input farming systems, has reduced the capacity of the major cereal crops to gain full benefit from AM interactions. Recent studies have shed further light on the molecular basis of establishment and functioning of AM symbiosis in cereals, providing insight into where the breeding process might have had an impact. Classic phytohormones, targets of artificial selection during the generation of Green Revolution semi-dwarf varieties, have emerged as important regulators of AM symbiosis. Although there is still much to be learnt about the mechanistic basis of variation in symbiotic outcome, these advances are providing an insight into the role of arbuscular mycorrhiza in agronomic systems. © 2018 The Authors. New Phytologist © 2018 New Phytologist Trust.

  13. Arbuscular mycorrhizal fungal communities in the rhizosphere of a continuous cropping soybean system at the seedling stage.

    Science.gov (United States)

    Cui, Jiaqi; Bai, Li; Liu, Xiaorui; Jie, Weiguang; Cai, Baiyan

    Arbuscular mycorrhizae (AM) fungi play a crucial role in the growth of soybean; however, the planting system employed is thought to have an effect on AM fungal communities in the rhizosphere. This study was performed to explore the influence of continuous soybean cropping on the diversity of Arbuscular mycorrhizal (AM) fungi, and to identify the dominant AM fungus during the seedling stage. Three soybean cultivars were planted under two and three years continuous cropping, respectively. The diversity of AM fungi in the rhizosphere soil at the seedling stage was subsequently analyzed using polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE). The results showed that an increase in cropping years improved the colonization rate of AM in all three soybean cultivars. Moreover, the dominant species were found to be Funneliformis mosseae and Glomus species. The results of cluster analysis further confirmed that the number of years of continuous cropping significantly affected the composition of rhizospheric AM fungal communities in different soybean cultivars. Copyright © 2017 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  14. Plant Functional Traits Associated with Mycorrhizal Root Foraging in Arbuscular Mycorrhizal and Ectomycorrhizal Trees

    Science.gov (United States)

    Eissenstat, D. M.; Chen, W.; Cheng, L.; Liu, B.; Koide, R. T.; Guo, D.

    2016-12-01

    Root foraging for nutrient "hot spots" is a key strategy by which some plants maximize nutrient gain from their carbon investment in root and mycorrhizal hyphae. Foraging strategies may depend on costs of root construction, with thick roots generally costing more per unit length than thin roots. Investment in mycorrhizal hyphae, which are considerably thinner than roots, may represent an alternative strategy for cost-effective nutrient foraging, especially for thick-root species. Type of mycorrhiza may matter, as ectomycorrhizal (EM) fungi are more associated with longer hyphae and ability to mineralize organic matter than arbuscular mycorrhizal (AM) fungi. Among AM trees in both subtropical forests in SE China and in temperate forests in central Pennsylvania, USA, we found that tree species with thin roots proliferated their roots in soil patches enriched with mineral nutrients to a greater extent than species with thick roots. In addition, thick-root species were consistently colonized more heavily with mycorrhizal fungi than thin root species, although nutrient addition tended to diminish colonization. In a common garden in central Pennsylvania of both AM and EM tree species, we found that nutrient patches enriched with organic materials resulted in greater root and mycorrhizal fungal proliferation compared to those enriched with inorganic nutrients and that thick-root species proliferated more with their mycorrhizal fungi whereas thin-root species proliferated more with their roots. We further examined with many more species, patterns of root and mycorrhizal fungal proliferation in organic-nutrient-enriched patches. Foraging precision, or the extent that roots or mycorrhizal hyphae grew in the enriched patch relative to the unenriched patch, was related to both root thickness and type of mycorrhiza. In both AM and EM trees, thick-root species were not selective foragers of either their roots or hyphae. In thin-root species, there was strong selectivity in

  15. Fungal associations of roots of dominant and sub-dominant plants in high-alpine vegetation systems with special reference to mycorrhiza.

    Science.gov (United States)

    Haselwandter, K; Read, D J

    1980-04-01

    Types of root infection were analysed in healthy dominant and sub-dominant plants of zonal and azonal vegetation above the timberline in the Central and Northern Calcareous Alps of Austria. In the open nival zone vegetation, infection by fungi of the Rhizoctonia type was predominant, vesicular-arbuscular mycorrhizal infection, which was mostly of the fine endophyte (Glomus tenuis) type, being light and mainly restricted to grasses in closed vegetation patches. More extensive Glomus tenuis infection was found in the alpine grass heath, but in Carex, Rhizoctonia was again the most important fungus. The ericaceous plants of the dwarf shrub heath have typical ericoid infection, but quantitative analysis reveals a decrease of infection intensity with increase of altitude. The possible function of the various types of root infection are discussed, and the status of Rhizoctonia as a possible mycorrhizal fungus is considered.

  16. Insights on the Impact of Arbuscular Mycorrhizal Symbiosis on Tomato Tolerance to Water Stress.

    Science.gov (United States)

    Chitarra, Walter; Pagliarani, Chiara; Maserti, Biancaelena; Lumini, Erica; Siciliano, Ilenia; Cascone, Pasquale; Schubert, Andrea; Gambino, Giorgio; Balestrini, Raffaella; Guerrieri, Emilio

    2016-06-01

    Arbuscular mycorrhizal (AM) fungi, which form symbioses with the roots of the most important crop species, are usually considered biofertilizers, whose exploitation could represent a promising avenue for the development in the future of a more sustainable next-generation agriculture. The best understood function in symbiosis is an improvement in plant mineral nutrient acquisition, as exchange for carbon compounds derived from the photosynthetic process: this can enhance host growth and tolerance to environmental stresses, such as water stress (WS). However, physiological and molecular mechanisms occurring in arbuscular mycorrhiza-colonized plants and directly involved in the mitigation of WS effects need to be further investigated. The main goal of this work is to verify the potential impact of AM symbiosis on the plant response to WS To this aim, the effect of two AM fungi (Funneliformis mosseae and Rhizophagus intraradices) on tomato (Solanum lycopersicum) under the WS condition was studied. A combined approach, involving ecophysiological, morphometric, biochemical, and molecular analyses, has been used to highlight the mechanisms involved in plant response to WS during AM symbiosis. Gene expression analyses focused on a set of target genes putatively involved in the plant response to drought, and in parallel, we considered the expression changes induced by the imposed stress on a group of fungal genes playing a key role in the water-transport process. Taken together, the results show that AM symbiosis positively affects the tolerance to WS in tomato, with a different plant response depending on the AM fungi species involved. © 2016 American Society of Plant Biologists. All Rights Reserved.

  17. 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

  18. Functional diversity in arbuscular mycorrhizas: Exploitation of soil patches with different phosphate enrichment differs among fungal species

    DEFF Research Database (Denmark)

    Cavagnaro, T.R.; Smith, F.A.; Smith, S.E.

    2005-01-01

    . This was studied by growing symbioses of Linum usitatissimum and three AMF (Glomus intraradices, G. mosseae and Gigaspora margarita) in pots with two side-arms, which were accessible to hyphae, but not to roots. Soil in one side-arm was either unamended (P0) or enriched with P; simultaneous labelling of this soil...

  19. 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

    fungi enhanced NUE by altering plant C assimilation and N uptake. AM plants had higher soluble sugar concentration and [K+]: [Na+] ratio compared with non-AM plants. It is concluded that AM symbiosis improves wheat plant growth at vegetative stages through increasing stomatal conductance, enhancing NUE...... 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......, accumulating soluble sugar, and improving ion homeostasis in wheat plants grown at elevated CO2 and salinity stress....

  20. Dynamic of Arbuscular Mycorrhiza (AM fungus in a Humic Dystrudepts sowed with corn Zea mays L. and Green Compost (GC

    Directory of Open Access Journals (Sweden)

    Francisco Javier Vélez Zabala

    2014-05-01

    Full Text Available Green Compost (GC have a positive impact on physical, chemical and biological properties of the soil, among them, the expression of the MA. In a Humic Dystrudepts in a mountainous area of Palmira (Valle five treatments were established: (T, fertilization of insdustrial chemical synthesis (FQ, green manure (AV, Compost (C and green manure compost (AVC, in a settlement of randomized complete blocks with three replications. As GC intermingled Canavalia ensiformis L. and Axonopus scoparius F., were harvested in prefloration of the legume, incorporated and became the first planting of corn, variety ICA V-354, monitored during 150 days, until time of fill of cob, when assessed length total external mycelium, LMET (Technical of the membrane filter method and the intercepted of Miller and Jastrow, that alive and active LMEV (succinate dehydrogenase, Hamel et al., 1990 and percentage of colonization by branch out manifold (Phillips and Hayman, 1980, described by Sieverding, 1983 and adapted for this crop, Sanchez et al. , 2010. The analysis of variance (SASR software version 9.1.3 showed that LMET, LMEV and % of branch out manifold showed highly significant differences between treatments. Greater LMET, coincided with increases in LMEV, colonization by branch out manifold and is presented in GC C, followed by AV, C and T, which did not vary among themselves, and, the lowest in CF. The coincidence of these three variables, would indicate that through LMET and especially, LMEV is absorbing and transporting P to the inside of the plants, and this supply, coinciding with higher % of colonization by branch out manifold, traces the path of the conjunction P in the soil-plantorganic fertilization, with their consequences on the economy of the agroecosystem and farmer.

  1. Hyphal growt and mycorrhiza formation by the arbuscular mycorrhizal fungus Glomus claroideum BEG 23 is stimulated by humic substances

    Czech Academy of Sciences Publication Activity Database

    Gryndler, Milan; Hršelová, Hana; Sudová, Radka; Gryndlerová, Hana; Řezáčová, Veronika; Merhautová, Věra

    2005-01-01

    Roč. 15, - (2005), s. 483-488 ISSN 0940-6360 R&D Projects: GA ČR GA526/03/0188; GA ČR GA526/00/1276 Institutional research plan: CEZ:AV0Z50200510; CEZ:AV0Z60050516 Keywords : fulvic acid * humic acid * iron Subject RIV: EE - Microbiology, Virology Impact factor: 1.753, year: 2005

  2. Armadillo motifs involved in vesicular transport.

    Directory of Open Access Journals (Sweden)

    Harald Striegl

    Full Text Available Armadillo (ARM repeat proteins function in various cellular processes including vesicular transport and membrane tethering. They contain an imperfect repeating sequence motif that forms a conserved three-dimensional structure. Recently, structural and functional insight into tethering mediated by the ARM-repeat protein p115 has been provided. Here we describe the p115 ARM-motifs for reasons of clarity and nomenclature and show that both sequence and structure are highly conserved among ARM-repeat proteins. We argue that there is no need to invoke repeat types other than ARM repeats for a proper description of the structure of the p115 globular head region. Additionally, we propose to define a new subfamily of ARM-like proteins and show lack of evidence that the ARM motifs found in p115 are present in other long coiled-coil tethering factors of the golgin family.

  3. Role of Intermediate Filaments in Vesicular Traffic

    Directory of Open Access Journals (Sweden)

    Azzurra Margiotta

    2016-04-01

    Full Text Available Intermediate filaments are an important component of the cellular cytoskeleton. The first established role attributed to intermediate filaments was the mechanical support to cells. However, it is now clear that intermediate filaments have many different roles affecting a variety of other biological functions, such as the organization of microtubules and microfilaments, the regulation of nuclear structure and activity, the control of cell cycle and the regulation of signal transduction pathways. Furthermore, a number of intermediate filament proteins have been involved in the acquisition of tumorigenic properties. Over the last years, a strong involvement of intermediate filament proteins in the regulation of several aspects of intracellular trafficking has strongly emerged. Here, we review the functions of intermediate filaments proteins focusing mainly on the recent knowledge gained from the discovery that intermediate filaments associate with key proteins of the vesicular membrane transport machinery. In particular, we analyze the current understanding of the contribution of intermediate filaments to the endocytic pathway.

  4. Growth responses of maritime sand dune plant species to arbuscular mycorrhizal fungi

    Directory of Open Access Journals (Sweden)

    Mariusz Tadych

    2014-08-01

    Full Text Available In a pot experiment conducted in a greenhouse, the response of 6 plant species dominating in the succession of vegetation of a deflation hollow of the Łeba Bar to inoculation with arbuscular mycorrhizal fungi (AMF was investigated. The inoculum was a mixture of soil, roots and spores of 5 species of AMF with the dominant species Glomus aggregatum. Except for Corynephorus canescens and Festuca rubra subsp. arenaria, both the growth and the dry matter of above-ground parts of plants of Agrostis stolonifera, Ammophila arenaria, Corynephorus canescens, Juncus articulatus and J. balticus inoculated with AMF were higher than those growing in soils lacking infection propagules of these fungi. Inoculation with AMF decreased the dry matter of root: shoot ratios in 5 plant species. This property was not determined in Festuca rubra subsp. arenaria due to the death of all control plants. The level of mycorrhizal infection was low and did not correlate with the growth responses found. The high growth reaction of Juncus spp. to AMF found in this study suggests that the opinion of non-mycotrophy or low dependence of plants of Juncaceae on AMF was based on results of investigations of plants growing in wet sites known to inhibit the formation of mycorrhizae.

  5. Effect of arbuscular mycorrhizal fungi on tomato yield and nutrient uptake under different fertilization levels

    Directory of Open Access Journals (Sweden)

    Ľudovít Nedorost

    2012-01-01

    Full Text Available Effect of the arbuscular mycorrhiza on tomato plants (Lycopersicon lycopersicum in the pot experiment was studied. Three different fertilization regimes (optimum – H1, stress a – H2, stress b - H3 and three different mycorrhizal treatments (control – Ctrl, Glomus mossae – Gm, Glomus intraradices – Gi were used. Economical parameter (yield, nutritional characteristic (vitamin C content, phosphates and minerals content, total antioxidant capacity, and level of root colonization were studied. The yield of the tomatoes was influenced by the basic dose of the fertilization, especially in the H2 and H3 treatment. The highest yield was in the H2 treatment in Gm (938 g per plant. The positive effect of the inoculation resulted in the increased content of the vitamin C. The highest significant influence was observed in the H2 treatment (plants inoculated with Gi with the average content of the vitamin C 289 mg.kg−1. The average rate of the colonization was in the range from 39 % to 65 %.

  6. Uptake of 15 trace elements in arbuscular mycorrhizal marigold measured by the multitracer technique

    International Nuclear Information System (INIS)

    Suzuki, H.; Kumagai, H.; Oohashi, K.; Sakamoto, K.; Inubushi, K.; Enomoto, S.; Ambe, F.

    2000-01-01

    The effect of arbuscular mycorrhizal (AM) colonization on the uptake of trace elements in marigold (Tagetes patula L.) was studied using a multitracer consisting of radionuclides of 7 Be, 22 Na, 46 Sc, 51 Cr, 54 Mn, 59 Fe, 56 Co, 65 Zn, 74 As, 75 Se, 83 Rb, 85 Sr, 88 Y, 88 Zr, and 95m Tc. Marigold plants were grown under controlled environmental conditions in sand culture either without mycorrhizas or in association with an AM fungus, Glomus etunicatum. The multitracer was applied to the pot, and plants were harvested at 7 and 21 d after tracer application. We found that the uptake of 7 Be, 22 Na, 51 Cr, 59 Fe, 65 Zn, and 95m Tc was higher in the mycorrhizal marigolds than in the non-mycorrhizal ones, while that of 46 Sc, 56 Co, 83 Rb, and 85 Sr was lower in the mycorrhizal marigolds than in the non-mycorrhizal ones. Thus, the multitracer technique enabled to analyze the uptake of various elements by plant simultaneously. It is suggested that this technique could be used to analyze the effects of AM colonization on the uptake of trace elements by plant. (author)

  7. High intraspecific genome diversity in the model arbuscular mycorrhizal symbiont Rhizophagus irregularis.

    Science.gov (United States)

    Chen, Eric C H; Morin, Emmanuelle; Beaudet, Denis; Noel, Jessica; Yildirir, Gokalp; Ndikumana, Steve; Charron, Philippe; St-Onge, Camille; Giorgi, John; Krüger, Manuela; Marton, Timea; Ropars, Jeanne; Grigoriev, Igor V; Hainaut, Matthieu; Henrissat, Bernard; Roux, Christophe; Martin, Francis; Corradi, Nicolas

    2018-01-22

    Arbuscular mycorrhizal fungi (AMF) are known to improve plant fitness through the establishment of mycorrhizal symbioses. Genetic and phenotypic variations among closely related AMF isolates can significantly affect plant growth, but the genomic changes underlying this variability are unclear. To address this issue, we improved the genome assembly and gene annotation of the model strain Rhizophagus irregularis DAOM197198, and compared its gene content with five isolates of R. irregularis sampled in the same field. All isolates harbor striking genome variations, with large numbers of isolate-specific genes, gene family expansions, and evidence of interisolate genetic exchange. The observed variability affects all gene ontology terms and PFAM protein domains, as well as putative mycorrhiza-induced small secreted effector-like proteins and other symbiosis differentially expressed genes. High variability is also found in active transposable elements. Overall, these findings indicate a substantial divergence in the functioning capacity of isolates harvested from the same field, and thus their genetic potential for adaptation to biotic and abiotic changes. Our data also provide a first glimpse into the genome diversity that resides within natural populations of these symbionts, and open avenues for future analyses of plant-AMF interactions that link AMF genome variation with plant phenotype and fitness. © 2018 The Authors. New Phytologist © 2018 New Phytologist Trust.

  8. Facilitation between woody and herbaceous plants that associate with arbuscular mycorrhizal fungi in temperate European forests.

    Science.gov (United States)

    Veresoglou, Stavros D; Wulf, Monika; Rillig, Matthias C

    2017-02-01

    In late-successional environments, low in available nutrient such as the forest understory, herbaceous plant individuals depend strongly on their mycorrhizal associates for survival. We tested whether in temperate European forests arbuscular mycorrhizal (AM) woody plants might facilitate the establishment of AM herbaceous plants in agreement with the mycorrhizal mediation hypothesis. We used a dataset spanning over 400 vegetation plots in the Weser-Elbe region (northwest Germany). Mycorrhizal status information was obtained from published resources, and Ellenberg indicator values were used to infer environmental data. We carried out tests for both relative richness and relative abundance of herbaceous plants. We found that the subset of herbaceous individuals that associated with AM profited when there was a high cover of AM woody plants. These relationships were retained when we accounted for environmental filtering effects using path analysis. Our findings build on the existing literature highlighting the prominent role of mycorrhiza as a coexistence mechanism in plant communities. From a nature conservation point of view, it may be possible to promote functional diversity in the forest understory through introducing AM woody trees in stands when absent.

  9. Comparative response of six grapevine rootstocks to inoculation with arbuscular mycorrhizal fungi based on root traits

    Science.gov (United States)

    Pogiatzis, Antreas; Bowen, Pat; Hart, Miranda; Holland, Taylor; Klironomos, John

    2017-04-01

    Arbuscular mycorrhizal (AM) symbiosis has been proven to be essential in grapevines, sustaining plant growth especially under abiotic and biotic stressors. The mycorrhizal growth response of young grapevines varies among rootstock cultivars and the underlying mechanisms involved in this variation are unknown. We predicted that this variation in mycorrhizal response may be explained by differences in root traits among rootstocks. We analyzed the entire root system of six greenhouse-grown rootstocks (Salt Creek, 3309 Couderc, Riparia Gloire, 101-14 Millardet et de Grasset, Swarzmann, Teleki 5C), with and without AM fungal inoculation (Rhizophagus irregularis) and characterized their morphological and architectural responses. Twenty weeks after the inoculation, aboveground growth was enhanced by AM colonization. The rootstock varieties were distinctly different in their response to AM fungi, with Salt Creek receiving the highest growth benefit, while Schwarzmann and 5C Teleki receiving the lowest. Plant responsiveness to AM fungi was negatively correlated with branching intensity (fine roots per root length). Furthermore, there was evidence that mycorrhizas can influence the expression of root traits, inducing a higher branching intensity and a lower root to shoot ratio. The results of this study will help to elucidate how interactions between grapevine rootstocks and AM fungi may benefit the establishment of new vineyards.

  10. Colonization with Arbuscular Mycorrhizal Fungi Promotes the Growth of Morus alba L. Seedlings under Greenhouse Conditions

    Directory of Open Access Journals (Sweden)

    Nan Lu

    2015-03-01

    Full Text Available Morus alba L. is an important tree species planted widely in China because of its economic value. In this report, we investigated the influence of two arbuscular mycorrhizal fungal (AMF species, Glomus mosseae and Glomus intraradices, alone and together, on the growth of M. alba L. seedlings under greenhouse conditions. The growth parameters and physiological performance of M. alba L. seedlings were evaluated 90 days after colonization with the fungi. The growth and physiological performance of M. alba L. seedlings were significantly affected by the AMF species. The mycorrhizal seedlings were taller, had longer roots, more leaves and a greater biomass than the non-mycorrhizae-treated seedlings. In addition, the AMF species-inoculated seedlings had increased root activity and a higher chlorophyll content compared to non-inoculated seedlings. Furthermore, AMF species colonization increased the phosphorus and nitrogen contents of the seedlings. In addition, simultaneous root colonization by the two AMF species did not improve the growth of M. alba L. seedlings compared with inoculation with either species alone. Based on these results, these AMF species may be applicable to mulberry seedling cultivation.

  11. Arbuscular common mycorrhizal networks mediate intra- and interspecific interactions of two prairie grasses.

    Science.gov (United States)

    Weremijewicz, Joanna; da Silveira Lobo O'Reilly Sternberg, Leonel; Janos, David P

    2018-01-01

    Arbuscular mycorrhizal fungi form extensive common mycorrhizal networks (CMNs) that may interconnect neighboring root systems of the same or different plant species, thereby potentially influencing the distribution of limiting mineral nutrients among plants. We examined how CMNs affected intra- and interspecific interactions within and between populations of Andropogon gerardii, a highly mycorrhiza dependent, dominant prairie grass and Elymus canadensis, a moderately dependent, subordinate prairie species. We grew A. gerardii and E. canadensis alone and intermixed in microcosms, with individual root systems isolated, but either interconnected by CMNs or with CMNs severed weekly. CMNs, which provided access to a large soil volume, improved survival of both A. gerardii and E. canadensis, but intensified intraspecific competition for A. gerardii. When mixed with E. canadensis, A. gerardii overyielded aboveground biomass in the presence of intact CMNs but not when CMNs were severed, suggesting that A. gerardii with intact CMNs most benefitted from weaker interspecific than intraspecific interactions across CMNs. CMNs improved manganese uptake by both species, with the largest plants receiving the most manganese. Enhanced growth in consequence of improved mineral nutrition led to large E. canadensis in intact CMNs experiencing water-stress, as indicated by 13 C isotope abundance. Our findings suggest that in prairie plant communities, CMNs may influence mineral nutrient distribution, water relations, within-species size hierarchies, and between-species interactions.

  12. Effect of arbuscular mycorrhizal (AM) fungi on 137Cs uptake by plants grown on different soils.

    Science.gov (United States)

    Vinichuk, M; Mårtensson, A; Ericsson, T; Rosén, K

    2013-01-01

    The potential use of mycorrhiza as a bioremediation agent for soils contaminated by radiocesium was evaluated in a greenhouse experiment. The uptake of (137)Cs by cucumber, perennial ryegrass, and sunflower after inoculation with a commercial arbuscular mycorrhizal (AM) product in soils contaminated with (137)Cs was investigated, with non-mycorrhizal quinoa included as a "reference" plant. The effect of cucumber and ryegrass inoculation with AM fungi on (137)Cs uptake was inconsistent. The effect of AM fungi was most pronounced in sunflower: both plant biomass and (137)Cs uptake increased on loamy sand and loamy soils. The total (137)Cs activity accumulated within AM host sunflower on loamy sand and loamy soils was 2.4 and 3.2-fold higher than in non-inoculated plants. Although the enhanced uptake of (137)Cs by quinoa plants on loamy soil inoculated by the AM fungi was observed, the infection of the fungi to the plants was not confirmed. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. Full establishment of arbuscular mycorrhizal symbiosis in rice occurs independently of enzymatic jasmonate biosynthesis.

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    Caroline Gutjahr

    Full Text Available Development of the mutualistic arbuscular mycorrhiza (AM symbiosis between most land plants and fungi of the Glomeromycota is regulated by phytohormones. The role of jasmonate (JA in AM colonization has been investigated in the dicotyledons Medicago truncatula, tomato and Nicotiana attenuata and contradicting results have been obtained with respect to a neutral, promotive or inhibitory effect of JA on AM colonization. Furthermore, it is currently unknown whether JA plays a role in AM colonization of monocotyledonous roots. Therefore we examined whether JA biosynthesis is required for AM colonization of the monocot rice. To this end we employed the rice mutant constitutive photomorphogenesis 2 (cpm2, which is deficient in JA biosynthesis. Through a time course experiment the amount and morphology of fungal colonization did not differ between wild-type and cpm2 roots. Furthermore, no significant difference in the expression of AM marker genes was detected between wild type and cpm2. However, treatment of wild-type roots with 50 μM JA lead to a decrease of AM colonization and this was correlated with induction of the defense gene PR4. These results indicate that JA is not required for AM colonization of rice but high levels of JA in the roots suppress AM development likely through the induction of defense.

  14. Modelling Spatial Interactions in the Arbuscular Mycorrhizal Symbiosis using the Calculus of Wrapped Compartments

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    Cristina Calcagno

    2011-09-01

    Full Text Available Arbuscular mycorrhiza (AM is the most wide-spread plant-fungus symbiosis on earth. Investigating this kind of symbiosis is considered one of the most promising ways to develop methods to nurture plants in more natural manners, avoiding the complex chemical productions used nowadays to produce artificial fertilizers. In previous work we used the Calculus of Wrapped Compartments (CWC to investigate different phases of the AM symbiosis. In this paper, we continue this line of research by modelling the colonisation of the plant root cells by the fungal hyphae spreading in the soil. This study requires the description of some spatial interaction. Although CWC has no explicit feature modelling a spatial geometry, the compartment labelling feature can be effectively exploited to define a discrete surface topology outlining the relevant sectors which determine the spatial properties of the system under consideration. Different situations and interesting spatial properties can be modelled and analysed in such a lightweight framework (which has not an explicit notion of geometry with coordinates and spatial metrics, thus exploiting the existing CWC simulation tool.

  15. An integrated functional approach to dissect systemic responses in maize to arbuscular mycorrhizal symbiosis.

    Science.gov (United States)

    Gerlach, Nina; Schmitz, Jessica; Polatajko, Aleksandra; Schlüter, Urte; Fahnenstich, Holger; Witt, Sandra; Fernie, Alisdair R; Uroic, Kalle; Scholz, Uwe; Sonnewald, Uwe; Bucher, Marcel

    2015-08-01

    Most terrestrial plants benefit from the symbiosis with arbuscular mycorrhizal fungi (AMF) mainly under nutrient-limited conditions. Here the crop plant Zea mays was grown with and without AMF in a bi-compartmented system separating plant and phosphate (Pi) source by a hyphae-permeable membrane. Thus, Pi was preferentially taken up via the mycorrhizal Pi uptake pathway while other nutrients were ubiquitously available. To study systemic effects of mycorrhizal Pi uptake on leaf status, leaves of these plants that display an increased biomass in the presence of AMF were subjected to simultaneous ionomic, transcriptomic and metabolomic analyses. We observed robust changes of the leaf elemental composition, that is, increase of P, S and Zn and decrease of Mn, Co and Li concentration in mycorrhizal plants. Although changes in anthocyanin and lipid metabolism point to an improved P status, a global increase in C versus N metabolism highlights the redistribution of metabolic pools including carbohydrates and amino acids. Strikingly, an induction of systemic defence gene expression and concomitant accumulation of secondary metabolites such as the terpenoids alpha- and beta-amyrin suggest priming of mycorrhizal maize leaves as a mycorrhiza-specific response. This work emphasizes the importance of AM symbiosis for the physiological status of plant leaves and could lead to strategies for optimized breeding of crop species with high growth potential. © 2015 John Wiley & Sons Ltd.

  16. The fficiency of Mycorrhiza biofertilizer treatment to the growth and yield of soybean

    Science.gov (United States)

    Samanhudi; Pujiasmanto, B.; Sudadi; Putra, I. H.; Mumtazah, H. M.

    2018-03-01

    Soybean is one of the major commodities in Indonesia. Due to its high demand, its requires an effort to increase the production. Soybeans are generally cultivated in dry land, for that its need a special management to increase the yield. The association between Mycorrhiza and roots help the plant to get water and nutrients. In this regard Mycorrhiza expected to increase soybean yield and efficiency. This research aim is to study the dose of Mycorrhiza on the growth and yield of soybean efficiently. The experiment was conducted in Selogiri District, Wonogiri, while the analysis of Mycorrhiza and soil was inFaculty of Agriculture, Universitas Sebelas Maret Surakarta from February to April 2016. Randomized Complete Block Design (RCBD) with two factors was emplyed for this experiment. The treatments are compost dose (derived from Waste Management Faculty of Agriculture UNS) and Mycorrhizal dose (obtained from BPPT Serpong). The result showed that the Mycorrhiza treatmentwas able to improved the growth and yield of soybean. The most efficient dose of is Mycorrhiza treatment at 0.64 ton ha-1.

  17. The use of nuclear and related techniques for evaluating the agronomic effectiveness of phosphate fertilizers, in particular rock phosphate, in Venezuela: II. Monitoring mycorrhizas and phosphate solubilizing microorganisms

    International Nuclear Information System (INIS)

    Casanova, E.; Salas, A.M.; Toro, M.

    2002-01-01

    The objectives of the study were to quantify and isolate P solubilizing microorganisms (fungus and bacteria) from corn, sorghum and beans rhizosphere from El Sombrero soil, located in Guarico state, a very important agricultural area in Venezuela. Rhizospheric soil samples were taken from the crops in the field and taken to the laboratory to conduct a serial dilution procedure in specific medium culture to obtain pure cultures and isolate microorganisms according to their function. The spores of arbuscular mycorrhiza (AM) from the soils were reproduced using trap pots in the greenhouse and after 4-6 months a dilute soil sample was wet-sieved and decanted for isolation of AM spores which were used for classification and for obtaining native pure cultures. Finally, the infective potential of AM was determined by setting pots with test crops and determining the AM colonization and efficiency to produce potential infection in the root system. There were no differences in the total microflora in both crop rhizospheres but there was a tendency of higher values in the corn rhizosphere due to the root exudates. Two solubilizing fungi identified were Aspergillus terreus and Aspergillus niger. (author)

  18. Micorrizas arbusculares no crescimento de mudas de sabiá em um substrato proveniente da mineração de manganês

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    Kaio Gráculo Vieira Garcia

    2016-04-01

    Full Text Available O manganês (Mn é considerado um micronutriente essencial às plantas, porém o seu excesso pode resultar em toxidez, causando clorose e necrose nas folhas. O uso de leguminosas inoculadas com fungos micorrízicos arbusculares tem se tornado uma importante estratégia do ponto de vista da remediação de áreas contaminadas com metais como é o caso do manganês. Neste sentido, o objetivo deste trabalho foi avaliar o crescimento de mudas de Mimosa caesalpiniaefolia Benth. inoculadas com micorrizas arbusculares sob condições de substrato esterilizado e natural proveniente de uma área de mineração de Mn do município de Ocara – CE. O experimento foi conduzido em casa de vegetação, utilizando-se o delineamento inteiramente casualizado, em esquema fatorial 4x2, considerando-se: quatro tratamentos de inoculação (controle não-inoculado, inoculado com Glomus clarum, inoculado com Glomus etunicatum e com a mistura dos dois fungos (Mix e duas condições de substrato (estéril e natural, com quatro repetições. As mudas de sabiá foram produzidas em bandeja de isopor, sendo transplantadas e inoculadas em vasos após treze dias da semeadura. Após trinta dias do transplantio foram realizadas avaliações de altura da parte áerea, diâmetro do colo, número de folíolos e porcentagem de sobrevivência. A inoculação com fungos micorrízicos arbusculares favoreceu o crescimento das mudas de sabiá em substrato da mineração de manganês, em condições naturais, principalmente quando se utilizou o Glomus etunicatum. No substrato esterilizado a inoculação com micorrizas arbusculares proporcionou a atenuação da toxidez de Mn nas mudas de sabiá favorecendo o crescimento das mesmas nestas condições.Arbuscular mycorrhiza on the growth of sabiá seedlings on a substrate from the manganese miningAbstract: Manganese (Mn is considered an essential micronutrient to plants but its excess can result in toxicity causing chlorosis and necrosis on

  19. The effect of potassium and mycorrhiza on growth of vanilla (Vanilla planifolia Andrew

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    I GEDE TIRTA

    2006-04-01

    Full Text Available The few and shallow roots caused slow growth of vanilla seedling. Mycorrhiza may increased the absorption of water and nutrients, while potassium may increased the rate of growth and strength of seedlings. This study was conducted at Sambangan Village, Buleleng, Bali in 2003 (April-Agustus 2003. The experiment was done in polybag and was arranged in Randomized Block Design with three replications. The treatments were consisted of two factors. The first factor was the rates of KCl fertilizer ( 0, 100 and 200 kg ha-1 or 0, 0,10 and 0,20 9 plant-1 and the second factor was the rates of mycorrhiza (0, 20 and 30 g plant-1. The aim of the research to study interactions between potassium and mycorrhiza and The optimum dosage the mycorrhiza on growth of vanilla (Vanilla planifolia Andrew. The resultes showed that there were interactions between potassium and mycorrhiza on fresh weight of the new shoot, root length and fresh root weight. The optimum dosage of the mycorrhiza was 20 g plant-1 with new shoot fresh weight was 25.63 g plant-1. The longest root (24.67 cm plant-1 was observed at the treatment without potasium with 20 g plant-1 mycorrhiza and this was 23% longer than control (19.93 cm plant-1. The highest fresh root weight (2.48 g plant-1 was observed at the dosage of 200 kg KCl ha-1 and 20 g mycorrhiza plant-1 and that was 55% heavier than control (1.60 g plant-1. The leaf number of the plant with 20 g plant-1 mycorrhiza was 6.22 and that was 18% more than control with leaf number 5.25. The total fresh weight of the seedling with 20 g plant-1 mycorrhiza was 86.74 g plant-1or 15% higher compared with control (75.18 g plant-1. The dosage of 100 kg KCl ha-1 increased the K content of the plant (2.45%K or 35% higher than control (1.81%K.

  20. Arbuscular mycorrhizal growth responses are fungal specific but do not differ between soybean genotypes with different phosphate efficiency.

    Science.gov (United States)

    Wang, Xiurong; Zhao, Shaopeng; Bücking, Heike

    2016-07-01

    Arbuscular mycorrhizal (AM) fungi play a key role in the phosphate (P) uptake of many important crop species, but the mechanisms that control their efficiency and their contribution to the P nutrition of the host plant are only poorly understood. The P uptake and growth potential of two soybean genotypes that differ in their root architectural traits and P acquisition efficiency were studied after colonization with different AM fungi and the transcript levels of plant P transporters involved in the plant or mycorrhizal P uptake pathway were examined. The mycorrhizal growth responses of both soybean genotypes ranged from highly beneficial to detrimental, and were dependent on the P supply conditions, and the fungal species involved. Only the colonization with Rhizophagus irregularis increased the growth and P uptake of both soybean genotypes. The expression of GmPT4 was downregulated, while the mycorrhiza-inducible P transporter GmPT10 was upregulated by colonization with R. irregularis Colonization with both fungi also led to higher transcript levels of the mycorrhiza-inducible P transporter GmPT9, but only in plants colonized with R. irregularis were the higher transcript levels correlated to a better P supply. The results suggest that AM fungi can also significantly contribute to the P uptake and growth potential of genotypes with a higher P acquisition efficiency, but that mycorrhizal P benefits depend strongly on the P supply conditions and the fungal species involved. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. Influencia de diferentes especies de fungo micorrizico arbuscular no desenvolvimento do crisântemo Influence of different species of arbuscular mycorrhizal fungi on chrysanthemum growth

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    Adriana Parada Dias da Silveira

    1996-01-01

    Full Text Available Com o objetivo de verificar o desenvolvimento e florescimento do crisântemo (Dendranthema grandiflora na presença de micorriza arbuscular, foi instalado, em casa de vegetação, um experimento, empregando-se os fungos Gigaspora margarita, Glomus leptotichum, Glomus macrocarpum e Scutellospora heterogama. Utilizou-se terra roxa estruturada, da Série Luiz de Queiroz, esterilizada (por autoclavagem e não esterilizada. No florescimento, colheram-se as plantas e determinaram-se a altura, a matéria seca da parte aérea, a matéria fresca da raiz, o teor de P e K na parte aérea, a colonização micorrízica e o número de esporos do fungo micorrízico. O desenvolvimento e o florescimento foram favorecidos pela inoculação de G. leptotichum e G.macrocarpum, quando as plantas foram cultivadas em solo esterilizado, superando o efeito dos fungos micorrízicos nativos. Entretanto, no solo não esterilizado, a inoculação dessas espécies de fungo não promoveu aumento no desenvolvimento da planta.A greenhouse experiment was conducted to verify the effect of arbuscular mycorrhiza on growth and flowering of chrysanthemum. Rooted plants were inoculated with Gigaspora margarita, Glomus leptotichum, Glomus macrocarpum e Scutellospora heterogama or non-inoculated. Plants were grown in a autoclave sterilized, and non-sterilized soil of the type "Terra Roxa Estruturada". At the flowering stage, plants were harvested and measured for plant height, shoot dry matter, root fresh matter, shoot P and K content, mycorrhizal root colonization and number of mycorrhizal fungi spores. Plants colonized with G.leptotichum and G. macrocarpum presented higher growth and flowering than control plants, in sterilized soil, overcoming the effect of native mycorrhizal fungi. However, there was no effect of introduced mycorrhizal fungi on non-sterilized soil.

  2. interaction between phosphorus fertilizer and arbuscular ...

    African Journals Online (AJOL)

    userpc

    examine the interaction between Phosphorus (P) fertilizer and Arbuscular Mycorrhizal Fungal ... recorded 28% and 4% total plant dry yield increment respectively over control. This study shows that ... ratio 1:3 inoculant: water, application per ... Table 1: Effect of P and AMF on the dry yield components of cassava (t ha-1).

  3. Interaction of arbuscular mycorrhizal fungus ( Glomus intraradices ...

    African Journals Online (AJOL)

    In this research, the effect of two arbuscular mycorrhizal fungal (AMF) inoculation (Glomus intraradices and Glomus etunicatum) on tomato plants growing in nutrient solution with high concentrations of copper were studied. Copper (Cu) is an essential micronutrient for plant growth. In the present study, the effect of copper ...

  4. Responses of potatoes plants inoculated with arbuscular ...

    African Journals Online (AJOL)

    A pot experiment was set to examine the impact of the foliar litter (Hardwickia binata and Azadirachta indica) and an arbuscular mycorrhizal (AM) fungus on the development of two varieties of potato plants (Aida, Atlas). Three litter doses (0, 25 and 50 g) were applied to the pots after bedding plantlets. The plants were ...

  5. Response of Arbuscular mycorrhizal fungi and Rhizobium ...

    African Journals Online (AJOL)

    The aim of the present study was to investigate the effect ofRhizobium and Arbuscular mycorrhizal fungi inoculation, both individually and in combination on growth and chlorophyll content of economically important plant Vigna unguiculata L. A significant (p < 0.05) increase over control in root length (45.6 cm), shoot height ...

  6. Common symbiosis genes CERBERUS and NSP1 provide additional insight into the establishment of arbuscular mycorrhizal and root nodule symbioses in Lotus japonicus.

    Science.gov (United States)

    Nagae, Miwa; Takeda, Naoya; Kawaguchi, Masayoshi

    2014-01-01

    Arbuscular mycorrhizal symbiosis (AMS) and root nodule symbiosis (RNS) share several common symbiotic components, and many of the common symbiosis mutants block the entry of symbionts into the roots. We recently reported that CERBERUS (an E3 ubiquitin ligase) and NSP1 (a GRAS family transcription factor), required for RNS, also modulate AMS development in Lotus japonicus. The novel common symbiosis mutants, cerberus and nsp1, have low colonization of arbuscular mycorrhiza (AM) fungi, caused by a defect in internal hyphal elongation and by a decreased fungal entry into the roots, respectively. Here, we showed that CERBERUS was induced at the sites of symbiotic fungal or bacterial infection. NSP1 has been implicated in a strigolactone biosynthesis gene DWARF27 expression. Nevertheless, in nsp1, DWARF27 was induced by inoculation with AM fungi, implying the existence of a NSP1-independent regulatory mechanism of strigolactone biosynthesis during AMS establishment. These results support functional analysis of CERBERUS and NSP1, and also contribute to elucidation of common mechanisms in AMS and RNS.

  7. Inoculation of Mimosa latispinosa Lam with the Commercial Arbuscular Mycorrhizal Fungus Rhizophagus irregularis DAOM 197198, and Bradyrhizobium spp. Under Nursery Production Conditions in South-East Madagascar

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    Sarasin, G.

    2017-01-01

    Full Text Available Qit Madagascar Minerals (QMM has planned several actions to reduce the environmental footprint of its mining project located near the city of Fort-Dauphin (Madagascar. One of these actions is the reclamation of a portion of its mined sites. Different symbiotic strains were tested as bio-enhancers for the ecological restoration using Mimosa latispinosa Lam, a native and pioneer shrub. The symbiotic strains tested in nursery were the commercial strain of arbuscular mycorrhizal fungus, Rhizophagus irregularis DAOM197198, and two local strains of Bradyrhizobium spp., STM1415 and STM1447, inoculated alone or dually with the arbuscular mycorrhiza. Treatments did not significantly increase the plant height and dry mass. However, plants grown in tyndallized soil had better growth than those in unsterilized soil. Results obtained twenty weeks after inoculation suggest that soil tyndallization (heating at 100°C and at atmospheric pressure of 700 kPa during three hours is an effective method for nursery production of high quality seedlings of M. latispinosa.

  8. Community assembly and coexistence in communities of arbuscular mycorrhizal fungi.

    Science.gov (United States)

    Vályi, Kriszta; Mardhiah, Ulfah; Rillig, Matthias C; Hempel, Stefan

    2016-10-01

    Arbuscular mycorrhizal fungi are asexual, obligately symbiotic fungi with unique morphology and genomic structure, which occupy a dual niche, that is, the soil and the host root. Consequently, the direct adoption of models for community assembly developed for other organism groups is not evident. In this paper we adapted modern coexistence and assembly theory to arbuscular mycorrhizal fungi. We review research on the elements of community assembly and coexistence of arbuscular mycorrhizal fungi, highlighting recent studies using molecular methods. By addressing several points from the individual to the community level where the application of modern community ecology terms runs into problems when arbuscular mycorrhizal fungi are concerned, we aim to account for these special circumstances from a mycocentric point of view. We suggest that hierarchical spatial structure of arbuscular mycorrhizal fungal communities should be explicitly taken into account in future studies. The conceptual framework we develop here for arbuscular mycorrhizal fungi is also adaptable for other host-associated microbial communities.

  9. The membrane proteome of Medicago truncatula roots displays qualitative and quantitative changes in response to arbuscular mycorrhizal symbiosis.

    Science.gov (United States)

    Abdallah, Cosette; Valot, Benoit; Guillier, Christelle; Mounier, Arnaud; Balliau, Thierry; Zivy, Michel; van Tuinen, Diederik; Renaut, Jenny; Wipf, Daniel; Dumas-Gaudot, Eliane; Recorbet, Ghislaine

    2014-08-28

    Arbuscular mycorrhizal (AM) symbiosis that associates roots of most land plants with soil-borne fungi (Glomeromycota), is characterized by reciprocal nutritional benefits. Fungal colonization of plant roots induces massive changes in cortical cells where the fungus differentiates an arbuscule, which drives proliferation of the plasma membrane. Despite the recognized importance of membrane proteins in sustaining AM symbiosis, the root microsomal proteome elicited upon mycorrhiza still remains to be explored. In this study, we first examined the qualitative composition of the root membrane proteome of Medicago truncatula after microsome enrichment and subsequent in depth analysis by GeLC-MS/MS. The results obtained highlighted the identification of 1226 root membrane protein candidates whose cellular and functional classifications predispose plastids and protein synthesis as prevalent organelle and function, respectively. Changes at the protein abundance level between the membrane proteomes of mycorrhizal and nonmycorrhizal roots were further monitored by spectral counting, which retrieved a total of 96 proteins that displayed a differential accumulation upon AM symbiosis. Besides the canonical markers of the periarbuscular membrane, new candidates supporting the importance of membrane trafficking events during mycorrhiza establishment/functioning were identified, including flotillin-like proteins. The data have been deposited to the ProteomeXchange with identifier PXD000875. During arbuscular mycorrhizal symbiosis, one of the most widespread mutualistic associations in nature, the endomembrane system of plant roots is believed to undergo qualitative and quantitative changes in order to sustain both the accommodation process of the AM fungus within cortical cells and the exchange of nutrients between symbionts. Large-scale GeLC-MS/MS proteomic analysis of the membrane fractions from mycorrhizal and nonmycorrhizal roots of M. truncatula coupled to spectral counting

  10. 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

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

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    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.

  12. Effects of Arbuscular Mycorrhizal Symbiosis (Glomus intraradice on Egyptian Broomrape (Orobanche aegyptiaca. Pers in Cultivated Tomato (Lycopersicon esculentum Mill.

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    mojtaba zafarian

    2017-03-01

    Full Text Available Introduction: Mycorrhizal symbiosis is one of the most popular and highest symbiotic relationship in plant kingdom. Most plants (about 80% of vascular plant species have at least one type of mycorrhiza. Arbuscular mycorrhizal fungies are the most important endomycorhiza fungi that play an important role in agriculture. Materials and Methods: In order to evaluate the effect of arbuscular mycorrhizal (Glomus intraradice symbiosis to control Egyptian Broomrape (Orobanche aegyptiaca. Pers in cultivated tomato (Lycopersicon esculentum Mill. growth, a glasshouse experiment was conducted in CRD design with four replications in Shahrekord university in summer 2014. Treatments consisted of four arbuscular mycorrhizal levels (50, 100, 150 and 200 kg ha-1 and two control treatments of weed free and weed infested treatments, respectively. In this experiment, seeds of speedy tomato cultivar planted in the bed that consisted of coco peat and peat moss were transplanted to the pots. Pots with diameter 20 and height 15 cm were filled with soil in the ratio 4: 1: 1 manure, sand and clay respectively and with 50 mg of Orobanche seeds that were collected in the previous year. It should be noted that the soil combination was disinfected at a temperature of 80OC for 72 h to reduce the potential effects of soil microbial population in reducing Orobanche germination. The fungal inoculation, containing sandy soil fungal body parts and organs fungal root was then added to each pot. Fungi strain was provided from the plant protection clinic located in Hamadan. Also, nutrition of tomato after being transplanted to pots was carried out with foliar application of complete micronutrient of 20-20-20 every 7 days under glasshouse condition. At the end of the season, were measured number of stems, number of nodules on the roots of tomato, time of emergence of orobanche flower on the soil surface, orobanche dry weight and tomato root and shoot dry weight. Statistical analysis of

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

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    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.

  14. 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

    Full Text Available Introduction: Sulfur is the key element for higher crops and plays an important role in the formation of proteins, vitamins, and enzymes. It is a constituent of amino acids such as cysteine and methionine, which act for the synthesis of other compounds containing reduced sulfur, such as chlorophyll and utilization of phosphorus and otheressential nutrients.Deficiency of this nutrient in soil is usually compensated by using chemical fertilizers. However, these fertilizers have harmful effects on the environment and decrease the quality of the agriculture products. Therefore, biological fertilizers are more useful for using in agricultural ecosystems.Sulfurshould be addedto the soil, usually in a reduced form such as elemental sulfur. Use of S oxidizers enhances the rate of natural oxidation of S and speeds up the production of sulfates and makes them available to plants consequently resulting in an increased plant yield. The role of chemolithotrophic bacteria of the genus Thiobacillus through oxidation process in the soil is usually emphasized. Sulfur oxidation is the most important step of sulfur cycle, which improves soil fertility. The result is formation of sulfate, which can be used by the plants, while the acidity produced by oxidation helps to solubilize nutrients in alkaline soils. These bacteria can solubilise the soil minerals through the production of H2SO4 that reacts with these non-soluble minerals and oxidised them to be available nutrients to the cultivated plants. Arbuscular MycorrhizalFungi isan important component ofthe microbiota, mutualistic symbioticsoilfungithatcolonizesthe rootsofmost cropplants.The AM symbiosis involves an about 80% of land plant species and 92% of plant families. They have theability to enhance host uptake of relativelyimmobile nutrientsparticularly phosphorus (P andzinc (Zn,Manganese (Mn andiron(Fe.Arbuscular mycorrhizal fungi increased plant uptake of phosphorus, nitrogen and water absorption

  15. A Recombinant Vesicular Stomatitis Virus Ebola Vaccine.

    Science.gov (United States)

    Regules, Jason A; Beigel, John H; Paolino, Kristopher M; Voell, Jocelyn; Castellano, Amy R; Hu, Zonghui; Muñoz, Paula; Moon, James E; Ruck, Richard C; Bennett, Jason W; Twomey, Patrick S; Gutiérrez, Ramiro L; Remich, Shon A; Hack, Holly R; Wisniewski, Meagan L; Josleyn, Matthew D; Kwilas, Steven A; Van Deusen, Nicole; Mbaya, Olivier Tshiani; Zhou, Yan; Stanley, Daphne A; Jing, Wang; Smith, Kirsten S; Shi, Meng; Ledgerwood, Julie E; Graham, Barney S; Sullivan, Nancy J; Jagodzinski, Linda L; Peel, Sheila A; Alimonti, Judie B; Hooper, Jay W; Silvera, Peter M; Martin, Brian K; Monath, Thomas P; Ramsey, W Jay; Link, Charles J; Lane, H Clifford; Michael, Nelson L; Davey, Richard T; Thomas, Stephen J

    2017-01-26

    The worst Ebola virus disease (EVD) outbreak in history has resulted in more than 28,000 cases and 11,000 deaths. We present the final results of two phase 1 trials of an attenuated, replication-competent, recombinant vesicular stomatitis virus (rVSV)-based vaccine candidate designed to prevent EVD. We conducted two phase 1, placebo-controlled, double-blind, dose-escalation trials of an rVSV-based vaccine candidate expressing the glycoprotein of a Zaire strain of Ebola virus (ZEBOV). A total of 39 adults at each site (78 participants in all) were consecutively enrolled into groups of 13. At each site, volunteers received one of three doses of the rVSV-ZEBOV vaccine (3 million plaque-forming units [PFU], 20 million PFU, or 100 million PFU) or placebo. Volunteers at one of the sites received a second dose at day 28. Safety and immunogenicity were assessed. The most common adverse events were injection-site pain, fatigue, myalgia, and headache. Transient rVSV viremia was noted in all the vaccine recipients after dose 1. The rates of adverse events and viremia were lower after the second dose than after the first dose. By day 28, all the vaccine recipients had seroconversion as assessed by an enzyme-linked immunosorbent assay (ELISA) against the glycoprotein of the ZEBOV-Kikwit strain. At day 28, geometric mean titers of antibodies against ZEBOV glycoprotein were higher in the groups that received 20 million PFU or 100 million PFU than in the group that received 3 million PFU, as assessed by ELISA and by pseudovirion neutralization assay. A second dose at 28 days after dose 1 significantly increased antibody titers at day 56, but the effect was diminished at 6 months. This Ebola vaccine candidate elicited anti-Ebola antibody responses. After vaccination, rVSV viremia occurred frequently but was transient. These results support further evaluation of the vaccine dose of 20 million PFU for preexposure prophylaxis and suggest that a second dose may boost antibody responses

  16. Succession of arbuscular mycorrhizal fungi in a deflation hollow of the Słowiński National Park, Poland

    Directory of Open Access Journals (Sweden)

    Mariusz Tadych

    2014-01-01

    Full Text Available In the years 1994-1995, the occurrence of arbuscular mycorrhizal fungi (AMF and arbuscular mycorrhizae (AM in eight successional stages of vegetation of a deflation hollow no. 12 of the Łeba Bar, Poland, was investigated. Early successional stages were colonized by members of the families Gramineae and Juncaceae, being gradually replaced by ericaceous plants in the middle and later stages and by trees in the most advanced stage corresponding to the Empetro nigri-Pinetum plant association. From the 96 soil samples collected, 21 species in three genera of AMF were recovered. The fungi most frequently found were members of the genus Acaulospora. The overall spore abundance, the species_ richness of AMF and the level of AM colonisation increased from stage 1 to reach a maximum in the middle stages and then gradually declined, being lowest in the forested stage 8. The values of the overall spore abundance and those of the abundances of the most frequently occurring AMF species strongly evidenced functioning in nature of the process of host-dependent differentiation of AMF communities. Of the five most numerously represented AMF species, the early colonizer and quickly diminishing in later successional stages was Glomus 107. The mid-late successor was A. koskei, and the latest - Glomus aggregatum. All measures of AMF presence negatively correlated with the content of organic C in the soil and most of them were negatively correlated with soil N-NO3 and P concentrations. In contrast, the occurrence of AMY and AM generally was positively correlated with soil pH and the K content of the soil.

  17. The effects of arbuscular mycorrhizal fungus and free living nitrogen fixing bacteria on growth, photosynthesis and yield of corn

    Directory of Open Access Journals (Sweden)

    mohsen jahan

    2009-06-01

    Full Text Available In recent years, biological fertilizers have received special attention by scientists in sustainable and low input agriculture. In order to study the effects of arbuscular mycorrhizal fungi and free living nitrogen fixing bacteria on growth and photosynthesis characteristics of corn in conventional and ecological cropping systems, a field experiment was conducted at the Research Farm of Ferdowsi University of Mashhad during year 2006. A split plots arrangement based on randomized complete block design with three replications was used. Treatments consisted four cropping systems (1- High input conventional system, 2- Medium input conventional system, 3- Low input conventional system and 4- Ecological system and four inoculations (1- Mycorrhiza fungus, Glomus intraradices, 2- Bacteria, Azotobacter paspali and Azospirillum brasilense, 3- Dual inoculation, Fungus plus bacteria, and 4- No-inoculation, control, which were allocated to main plots and sub plots, respectively. All agronomic practices and inputs application during planting and nursing for each of cropping systems were conducted according to regional traditions. Results showed that the effect of inoculation on photosynthesis rates of corn was significant, as the highest photosynthesis rate obtained in dual inoculation. Single inoculation (fungus or bacteria was ranked second. The effect of all inoculations on corn dry matter production was significant and dual inoculation produced the highest dry matter yield. The cropping systems have significant effect on corn yield and the difference between medium input conventional system and high input conventional system was significant, but the high input, low input and ecological cropping systems showed no differences. Inoculants affected the SPAD readings, and dual inoculation showed the highest SPAD readings. This study showed that utilization of low input conventional and ecological systems in combination with use of dual inoculation of

  18. 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.

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

    International Nuclear Information System (INIS)

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

    2001-01-01

    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

  20. Nitrogen transfer via VA mycorrhiza hyphae link between roots of red clover

    International Nuclear Information System (INIS)

    Zhang Junling; Li Xiaolin; Yang Zhifu

    1997-01-01

    Five compartments with a air gap was designed to examine underground N transfer via VAM hyphae link between roots of red clover. 15 N was injected into the root compartment for donor plant 4 weeks after planting. Plants were harvested 6 weeks afterwards. The experiment had four treatments: two N levels (receiver root compartment); mycorrhiza and non-mycorrhiza treatment (B compartment), and each with four replicates. It was demonstrated that there was no significant difference in 15 N abundance in receiver red clover regardless of the inoculation of mycorrhiza fungi and nitrogen fertilization. Both shoot and root dry weight of receiver plants were not affected too, however, plant P and N nutrient status got better under this condition

  1. Vesicular storage and release of acetylcholine in Torpedo electroplaque synapses

    Energy Technology Data Exchange (ETDEWEB)

    Suszkiw, J B; Zimmermann, H; Whittaker, V P [Max-Planck-Institut fuer Biophysikalische Chemie (Karl-Friedrich-Bonhoefer-Inst.), Goettingen (Germany, F.R.)

    1978-06-01

    The disposition of newly synthesized ACh subsequent to depletion of vesicular endogenous ACh by stimulation was studied in the electromotor nerve terminals of Torpedo marmorata using (/sup 3/H) acetate as a precursor of ACh. Little vesicular (/sup 3/H) ACh could be isolated from tissue immediately after stimulation at 1 Hz. After 3 h post-stimulation recovery the newly-synthesized (/sup 3/H) ACh is found predominantly in a subpopulation of vesicles distinct from the vesicles containing most of the endogenous poorly labelled ACh. Restimulation of the tissue causes release of highly labelled ACh with a specific radioactivity (SRA) comparable to that of the newly synthesized (/sup 3/H) ACh in the highly labelled subpopulation of vesicles and significantly greater than the SRA of ACh in the main vesicular pool of the total tissue.

  2. Effects of bradyrhiziobium and vesicular arbuscular mycorrhizal (VAM) inoculation on symbiotic properties, yield and seed quality of groundnut

    Energy Technology Data Exchange (ETDEWEB)

    Mohamedzein, Ekhlas Mohamedzein M [Department of Biochemistry and Soil Science, Faculty of agriculture, University of Khartoum, Khartoum (Sudan)

    1996-11-01

    A local and introduced Bradyrhizobium strains and a locally-isolated VAM fungi were used to study their effects on groundnut in clay (Shambat) and sandy (El-Rwakeeb) soil in a pot experiment. A field experiment was carried out at El-Rwakeeb to study the effect of urea, superphosphate and chicken manure on inoculated or uninoculated groundnut. Inoculation significantly increased number of nodules, dry weight of shoot, root and nodules, plant N and P content, number and dry weight of pods, yield and seed composition and quality in both pot and field experiments. Introduced strain (TAL 1000) was more effective than locally- isolated strain (ENRRI 16). All fertilizers added to inoculated or uninoculated groundnut significantly increased all measured parameters. Chiken manure reflected good results than rea and superphosphate, which showed comparable results. All treatents significantly improved the seed composition especially protein and oil content. (Author) 89 refs. , 25 tabs.

  3. 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

    colonization at all three levels of N supply, but this effect was strongest in plants of low N status. The results indicated that this increase was due partly to the improved inflow of N via the external hyphae. Root colonization by G. intraradices was unaffected by the amount of N supplied to the RC, while...... hyphal length increased in HC(A) compared to HC(B). Although a considerable N-15 content was detected in mycorrhizal roots adjacent to HC(B), only insignificant amounts of N-15 were found in the external hyphae in HC(B). The external hyphae depleted the soil of inorganic N in both HC(A) and HC(B), while...

  4. Symbiont effect of Rhizobium bacteria and vesicular arbuscular mycorrhizal fungi on Pisum sativum in recultivated mine spoils

    Energy Technology Data Exchange (ETDEWEB)

    Biro, B.; Voros, I.; Kovespechy, K.; Szegi, J. (Hungarian Academy of Sciences, Budapest (Hungary). Soil Science and Agricultural Chemistry Research Institute)

    The frequency (F%) of spontaneous endomycorrhizal fungal infection (AMF) and the root modulation of Pisum sativum L, was studied after 8 and 15 years of recultivation in 4 soils (andesitic tuff yellow sand, yellow clay, and grey clay) disturbed by mining activities. The effects of Rhizobium inoculation and the interaction of both microsymbionts with plant production were also examined along with humus content and the humus stability coefficient, in the following variations: control, NPK fertilizer, NPK+lignite, NPK+straw and sewage sludge. Dump spoils originating from deep geological layers were poor in organic materials. After 12 years of recultivation, the humus content increased significantly. No such increase was noted in grey clay and the natural, brown forest soil used as an undisturbed (control) sample. The degradation of soils by mining brings about a decrease in the rhizobial and mycorrhizal population, so the number of spontaneous Rhizobium nodules is relatively low and does not influence the yield of peas. Inoculation with a selected effective strain of Rhizobium leguminosarum bv. viceae, however, enhanced dry matter production in these microbiologically degraded soils. Although the frequency of AMF infection was also higher after rhizobial inoculation, no positive correlation was found between dry matter production of peas and the F% of AMF. Spoils treated with lignite, straw, and sewage sludge had an especially high level of spontaneous mycorrhizal populations, indicating that organic materials had a favorable effect on the recultivation processes and fertility of mine spoils.

  5. Effects of bradyrhiziobium and vesicular arbuscular mycorrhizal (VAM) inoculation on symbiotic properties, yield and seed quality of groundnut

    International Nuclear Information System (INIS)

    Mohamedzein, Ekhlas Mohamedzein M.

    1996-11-01

    A local and introduced Bradyrhizobium strains and a locally-isolated VAM fungi were used to study their effects on groundnut in clay (Shambat) and sandy (El-Rwakeeb) soil in a pot experiment. A field experiment was carried out at El-Rwakeeb to study the effect of urea, superphosphate and chicken manure on inoculated or uninoculated groundnut. Inoculation significantly increased number of nodules, dry weight of shoot, root and nodules, plant N and P content, number and dry weight of pods, yield and seed composition and quality in both pot and field experiments. Introduced strain (TAL 1000) was more effective than locally- isolated strain (ENRRI 16). All fertilizers added to inoculated or uninoculated groundnut significantly increased all measured parameters. Chiken manure reflected good results than rea and superphosphate, which showed comparable results. All treatents significantly improved the seed composition especially protein and oil content. (Author)

  6. 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

  7. Structural modifications of vesicular aggregates following gamma-irradiation

    International Nuclear Information System (INIS)

    Mantaka-Marketou, A.E.; Domasou, A.S.

    1991-01-01

    The structural changes of the didodecyldimethylammonium bromide (DDAB) vesicular bilayers after γ-irradiation and under conditions where mainly OH radicals are present are reported. Alterations of the vesicular structure, such as polarity and fluidity, were detected after a dose of 0.65 kGy. A higher dose of ∼14kGy cause important damage to the well organized molecular structure and this is manifested by an important augmentation of the fluidity and polarity of the Stern region of the aggregates. Increased water penetration into the bilayer of the vesicle is probably the reason for these changes and electron micrographs support this hypothesis. (author)

  8. Contribuição de fungos micorrízicos arbusculares autóctones no crescimento de Guazuma ulmifolia em solo de cerrado degradado Contribution of arbuscular mycorrhizal fungi to the growth of Guazuma ulmifolia in degraded 'cerrado' soil

    Directory of Open Access Journals (Sweden)

    Sueli da Silva Aquino

    2002-12-01

    Full Text Available Ensaios foram conduzidos, em casa de vegetação, com solos de pastagem degradada reflorestada e cerrado preservado (controle visando avaliar a contribuição de fungos micorrízicos arbusculares (FMA autóctones no crescimento de mutambo (Guazuma ulmifolia Lamb.. As mudas foram transplantadas para sacos de plástico (2 kg com substratos esterilizados na proporção 4:1 (solo:areia, e o tratamento inoculado recebeu 300 esporos de FMA por saco. A inoculação não proporcionou aumento significativo na produção da matéria seca da parte aérea, matéria fresca das raízes e altura da planta, sugerindo que a G. ulmifolia não é responsiva à micorrização.Experiments were carried out in a greenhouse, using reforested degraded pasture and preserved 'cerrado' (control soil with the objective to evaluate the contribution of autoctone arbuscular mycorrhizal fungi (AMF on the Guazuma ulmifolia Lamb. growth. Seedlings were transplanted to plastic bags with 2 kg of sterilized soil: sand substrate (4:1. Plants were inoculated with ca. 300 spores of AMF per replication; noninoculated plants served as control. AMF did not improve significantly canopy dry matter, root fresh matter and plant height. G. ulmifolia showed no response to mycorrhizae.

  9. Interactive effects of aluminum, phosphorus and mycorrhizae on growth and nutrient uptake of Panicum virgatum L. (Poaceae).

    Science.gov (United States)

    Koslowsky, S D; Boener, R E

    1989-01-01

    The effects of Al on Panicum virgatum (switchgrass), a widespread perennial grass, were determined in relation to factors which might interact with Al in the soil. Plants were grown for 8 weeks in sand culture and were treated with 3 Al levels (0.5, 2.0, 5.0 mM), 2 P levels (0.065, 0.161 mM), 2 inoculum types (vesicular-arbuscular mycorrhizal (VAM) inoculum or VAM-free soil inoculum) and 2 inoculum sources (a high Al forest in NY or a low Al forest in Ohio) in a factorial design. Plant growth decreased with increasing Al and increased with increasing P, but the Al effect was less at high P than low P. VAM-inoculated plants outgrew non-VAM plants, especially at low and medium Al levels. Total P and Ca uptake decreased with increasing Al concentration, especially at low P levels. VAM inoculation did not result in increased P uptake at any Al level though VAM plants took up significantly more Ca than non-VAM plants at any Al level. VAM plants had lower tissue Al concentrations and took up less Al than non-VAM plants; Al uptake increased with increasing soil Al in non-VAM plants but not in VAM plants. Plants given inoculum from the high Al site had significantly lower tissue Al than plants given the low Al site inoculum, regardless of VAM status. We conclude that the presence of a VAM infection, moderate levels of soil P, and the source of the inoculum can reduce the effects of soluble Al. We discuss potential physiological and edaphic mechanisms by which Al may be immobilized and Ca availability increased in the presence of VAM fungi and other soil microflora.

  10. Colonization of new land by arbuscular mycorrhizal fungi

    DEFF Research Database (Denmark)

    Nielsen, Knud Nor; Kjøller, Rasmus; Bruun, Hans Henrik

    2016-01-01

    The study describes the primary assembly of arbuscular mycorrhizal communities on a newly constructed island Peberholm between Denmark and Sweden. The AM fungal community on Peberholm was compared with the neighboring natural island Saltholm. The structure of arbuscular mycorrhizal communities wa...

  11. Subaqueous non-vesicular to poorly-vesicular shards: hydroclastic fragmentation on seamounts and summit calderas

    Science.gov (United States)

    Mueller, W. U.; Dingwell, D. B.; Downey, W. S.; Mastin, L. G.

    2008-12-01

    Recognizing pyroclastic deposits that originate directly from magmatic and phreatomagmatic explosions in a subaqueous setting is based upon sedimentary structures, such as massive, stratified, and graded beds as well as (pyro)clast size. Ideally such deposits form ordered fining-and thinning-upward sequences. Pumice, scoria, glass shards, euhedral and broken crystals, and lithic fragments are constituents that support an explosive heritage. Recent deep-sea ROV and submersible dives have retrieved non-vesicular to vesicle- poor, mm-scale, mafic shards in 5-15 cm-thick massive and/or graded (stratified) deposits, for which a subaqueous explosive origin has been inferred. These sheet hyaloclastites with variable shard shapes were first documented on Seamount 6 as deep-sea Limu O Pele at water depths > 1000 m. We identified in Seamount 6 samples equant to blocky shards with angular to subrounded terminations, but also subordinate hair-like and contorted glassy filaments, warped shards and irregular shards. Shards display internal laminations (flow-banding?) and have local perlitic fractures. Bubble wall shards derived from scoria burst were rare. In combination with all the above and a poor shard vesicularity (tubes and ponded magma in depths > 1000 m. We envision that hydrostatic pressure commensurate with water depth played a significant role. The deposits can be readily explained by a hydroclastic process whereby fragmentation occurred at the milli-second (Limu) to second scale (hyaloclastite). Hence, hyperquenched glass shards or thread-like glass filaments need not require magmatic explosivity. Constant surface interaction between aphyric, low-viscosity, high temperature, magma-lava at depth with seawater causes fragmentation (granulation) that can generate such delicate shards. The transfer of heat to the ambient medium, seawater, favours turbulent convection causing strong water movement that strips glassy rinds and lofts the fine-grained shards and Limu O Pele

  12. Role of extrinsic arbuscular mycorrhizal fungi in heavy metal-contaminated wetlands with various soil moisture levels.

    Science.gov (United States)

    Zheng, S; Wang, C; Shen, Z; Quan, Y; Liu, X

    2015-01-01

    This study presents an efficient heavy metal (HM) control method in HM-contaminated wetlands with varied soil moisture levels through the introduction of extrinsic arbuscular mycorrhizal fungi (AMF) into natural wetland soil containing indigenous AMF species. A pot culture experiment was designed to determine the effect of two soil water contents (5-8% and 25-30%), five extrinsic AMF inoculants (Glomus mosseae, G. clarum, G. claroideum, G. etunicatum, and G. intraradices), and HM contamination on root colonization, plant growth, and element uptake of common reed (Phragmites australis (Cav.) Trin. ex Steudel) plantlets in wetland soils. This study showed the prevalence of mycorrhizae in the roots of all P. australis plantlets, regardless of extrinsic AMF inoculations, varied soil moisture or HM levels. It seems that different extrinsic AMF inoculations effectively lowered HM concentrations in the aboveground tissues of P. australis at two soil moisture levels. However, metal species, metal concentrations, and soil moisture should also be very important factors influencing the elemental uptake performance of plants in wetland ecosystems. Besides, the soil moisture level significantly influenced plant growth (including height, and shoot and root dry weight (DW)), and extrinsic AMF inoculations differently affected shoot DW.

  13. Arbuscular mycorrhizal fungi can decrease the uptake of uranium by subterranean clover grown at high levels of uranium in soil

    International Nuclear Information System (INIS)

    Rufyikiri, Gervais; Huysmans, Lien; Wannijn, Jean; Hees, May van; Leyval, Corinne; Jakobsen, Iver

    2004-01-01

    Subterranean clover inoculated or not with the arbuscular mycorrhizal (AM) fungus Glomus intraradices was grown on soil containing six levels of 238 U in the range 0-87 mg kg -1 . Increasing U concentration in soil enhanced the U concentration in roots and shoots of both mycorrhizal and nonmycorrhizal plants but had no significant effects on plant dry matter production or root AM colonization. Mycorrhizas increased the shoot dry matter and P concentration in roots and shoots, while in most cases, it decreased the Ca, Mg and K concentrations in plants. The AM fungus influenced U concentration in plants only in the treatment receiving 87 mg U kg -1 soil. In this case, U concentration in shoots of nonmycorrhizal plants was 1.7 times that of shoots of mycorrhizal plants. These results suggested that mycorrhizal fungi can limit U accumulation by plants exposed to high levels of U in soil. - Plant mycorrhization may decrease U concentration in shoots of plants grown at high level of U in soil

  14. Underground friends or enemies: model plants help to unravel direct and indirect effects of arbuscular mycorrhizal fungi on plant competition.

    Science.gov (United States)

    Facelli, Evelina; Smith, Sally E; Facelli, José M; Christophersen, Helle M; Andrew Smith, F

    2010-03-01

    *We studied the effects of two arbuscular mycorrhizal (AM) fungi, singly or together, on the outcome of competition between a host (tomato cultivar, wild-type (WT)) and a surrogate nonhost (rmc, a mycorrhiza-defective mutant of WT) as influenced by the contributions of the direct and AM phosphorus (P) uptake pathways to plant P. *We grew plants singly or in pairs of the same or different genotypes (inoculated or not) in pots containing a small compartment with (32)P-labelled soil accessible to AM fungal hyphae and determined expression of orthophosphate (P(i)) transporter genes involved in both AM and direct P uptake. *Gigaspora margarita increased WT competitive effects on rmc. WT and rmc inoculated with Glomus intraradices both showed growth depressions, which were mitigated when G. margarita was present. Orthophosphate transporter gene expression and (32)P transfer showed that the AM pathway operated in single inoculated WT, but not in rmc. *Effects of AM fungi on plant competition depended on the relative contributions of AM and direct pathways of P uptake. Glomus intraradices reduced the efficiency of direct uptake in both WT and rmc. The two-fungus combination showed that interactions between fungi are important in determining outcomes of plant competition.

  15. Arbuscular Mycorrhizal Symbiosis with Arundo donax Decreases Root Respiration and Increases Both Photosynthesis and Plant Biomass Accumulation.

    Science.gov (United States)

    Romero-Munar, Antònia; Del-Saz, Néstor Fernández; Ribas-Carbó, Miquel; Flexas, Jaume; Baraza, Elena; Florez-Sarasa, Igor; Fernie, Alisdair Robert; Gulías, Javier

    2017-07-01

    The effect of arbuscular mycorrhiza (AM) symbiosis on plant growth is associated with the balance between costs and benefits. A feedback regulation loop has been described in which the higher carbohydrate cost to plants for AM symbiosis is compensated by increases in their photosynthetic rates. Nevertheless, plant carbon balance depends both on photosynthetic carbon uptake and respiratory carbon consumption. The hypothesis behind this research was that the role of respiration in plant growth under AM symbiosis may be as important as that of photosynthesis. This hypothesis was tested in Arundo donax L. plantlets inoculated with Rhizophagus irregularis and Funneliformis mosseae. We tested the effects of AM inoculation on both photosynthetic capacity and in vivo leaf and root respiration. Additionally, analyses of the primary metabolism and ion content were performed in both leaves and roots. AM inoculation increased photosynthesis through increased CO 2 diffusion and electron transport in the chloroplast. Moreover, respiration decreased only in AM roots via the cytochrome oxidase pathway (COP) as measured by the oxygen isotope technique. This decline in the COP can be related to the reduced respiratory metabolism and substrates (sugars and tricarboxylic acid cycle intermediates) observed in roots. © 2017 John Wiley & Sons Ltd.

  16. Practical Microform Materials for Libraries: Silver, Diazo, Vesicular.

    Science.gov (United States)

    Veaner, Allen B.

    1982-01-01

    Remarks on the relative permanence and durability of three types of film in use in library microform reproduction (silver, diazo, and vesicular) and points out some technical and economic facts that govern the choice of microform materials for libraries. A 6-item reference list is included. (Author/JL)

  17. Reconstitution of the fusogenic activity of vesicular stomatitis virus

    NARCIS (Netherlands)

    Metsikkö, K.; van Meer, G.; Simons, K.

    1986-01-01

    Enveloped virus glycoproteins exhibit membrane fusion activity. We have analysed whether the G protein of vesicular stomatitis virus, reconstituted into liposomes, is able to fuse nucleated cells in a pH-dependent fashion. Proteoliposomes produced by octylglucoside dialysis did not exhibit cell

  18. Renal epithelial cells can release ATP by vesicular fusion

    Directory of Open Access Journals (Sweden)

    Randi G Bjaelde

    2013-09-01

    Full Text Available Renal epithelial cells have the ability to release nucleotides as paracrine factors. In the intercalated cells of the collecting duct, ATP is released by connexin30 (cx30, which is selectively expressed in this cell type. However, ATP is released by virtually all renal epithelia and the aim of the present study was to identify possible alternative nucleotide release pathways in a renal epithelial cell model. We used MDCK (type1 cells to screen for various potential ATP release pathways. In these cells, inhibition of the vesicular H+-ATPases (bafilomycin reduced both the spontaneous and hypotonically (80%-induced nucleotide release. Interference with vesicular fusion using N-ethylamide markedly reduced the spontaneous nucleotide release, as did interference with trafficking from the endoplasmic reticulum to the Golgi apparatus (brefeldin A1 and vesicular transport (nocodazole. These findings were substantiated using a siRNA directed against SNAP-23, which significantly reduced spontaneous ATP release. Inhibition of pannexin and connexins did not affect the spontaneous ATP release in this cell type, which consists of ∼90% principal cells. TIRF-microscopy of either fluorescently-labeled ATP (MANT-ATP or quinacrine-loaded vesicles, revealed that spontaneous release of single vesicles could be promoted by either hypoosmolality (50% or ionomycin. This vesicular release decreased the overall cellular fluorescence by 5.8% and 7.6% respectively. In summary, this study supports the notion that spontaneous and induced ATP release can occur via exocytosis in renal epithelial cells.

  19. Transcriptome Analysis of Arbuscular Mycorrhizal Roots during Development of the Prepenetration Apparatus1[W

    Science.gov (United States)

    Siciliano, Valeria; Genre, Andrea; Balestrini, Raffaella; Cappellazzo, Gilda; deWit, Pierre J.G.M.; Bonfante, Paola

    2007-01-01

    Information on changes in the plant transcriptome during early interaction with arbuscular mycorrhizal (AM) fungi is still limited since infections are usually not synchronized and plant markers for early stages of colonization are not yet available. A prepenetration apparatus (PPA), organized in epidermal cells during appressorium development, has been reported to be responsible for assembling a trans-cellular tunnel to accommodate the invading fungus. Here, we used PPAs as markers for cell responsiveness to fungal contact to investigate gene expression at this early stage of infection with minimal transcript dilution. PPAs were identified by confocal microscopy in transformed roots of Medicago truncatula expressing green fluorescent protein-HDEL, colonized by the AM fungus Gigaspora margarita. A PPA-targeted suppressive-subtractive cDNA library was built, the cDNAs were cloned and sequenced, and, consequently, 107 putative interaction-specific genes were identified. The expression of a subset of 15 genes, selected by reverse northern dot blot screening, and five additional genes, potentially involved in PPA formation, was analyzed by real-time reverse transcription-polymerase chain reaction and compared with an infection stage, 48 h after the onset of the PPA. Comparison of the expression profile of G. margarita-inoculated wild type and the mycorrhiza-defective dmi3-1 mutant of M. truncatula revealed that an expansin-like gene, expressed in wild-type epidermis during PPA development, can be regarded as an early host marker for successful mycorrhization. A putative Avr9/Cf-9 rapidly elicited gene, found to be up-regulated in the mutant, suggests novel regulatory roles for the DMI3 protein in the early mycorrhization process. PMID:17468219

  20. The potential role of Arbuscular Mycorrhizal Fungi in the restoration of degraded lands

    Directory of Open Access Journals (Sweden)

    Fisseha Asmelash Belay

    2016-07-01

    Full Text Available Experiences worldwide reveal that degraded lands restoration projects achieve little success or fail. Hence, understanding the underlining causes and accordingly, devising appropriate restoration mechanisms is crucial. In doing so, the ever-increasing aspiration and global commitments in degraded lands restoration could be realized. Here we explain that Arbuscular Mycorrhizal Fungi (AMF biotechnology is a potential mechanism to significantly improve the restoration success of degraded lands. There are abundant scientific evidences to demonstrate that AMF significantly improve soil attributes, increase above and belowground biodiversity, significantly improve tree/shrub seedlings survival, growth and establishment on moisture and nutrient stressed soils. AMF have also been shown to drive plant succession and may prevent invasion by alien species. The very few conditions where infective AMF are low in abundance and diversity is when the soil erodes, is disturbed and is devoid of vegetation cover. These are all common features of degraded lands. Meanwhile, degraded lands harbor low levels of infective AMF abundance and diversity. Therefore, the successful restoration of infective AMF can potentially improve the restoration success of degraded lands. Better AMF inoculation effects result when inocula are composed of native fungi instead of exotics, early seral instead of late seral fungi, and are consortia instead of few or single species. Future research efforts should focus on AMF effect on plant community primary productivity and plant competition. Further investigation focusing on forest ecosystems and carried out at the field condition is highly recommended. Devising cheap and ethically widely accepted inocula production methods and better ways of AMF in-situ management for effective restoration of degraded lands will also remain to be important research areas. Keywords: AMF, ecological restoration, facilitation, inoculation, land degradation

  1. Reduced aboveground tree growth associated with higher arbuscular mycorrhizal fungal diversity in tropical forest restoration.

    Science.gov (United States)

    Holste, Ellen K; Holl, Karen D; Zahawi, Rakan A; Kobe, Richard K

    2016-10-01

    Establishing diverse mycorrhizal fungal communities is considered important for forest recovery, yet mycorrhizae may have complex effects on tree growth depending on the composition of fungal species present. In an effort to understand the role of mycorrhizal fungi community in forest restoration in southern Costa Rica, we sampled the arbuscular mycorrhizal fungal (AMF) community across eight sites that were planted with the same species ( Inga edulis, Erythrina poeppigiana, Terminalia amazonia, and Vochysia guatemalensis ) but varied twofold to fourfold in overall tree growth rates. The AMF community was measured in multiple ways: as percent colonization of host tree roots, by DNA isolation of the fungal species associated with the roots, and through spore density, volume, and identity in both the wet and dry seasons. Consistent with prior tropical restoration research, the majority of fungal species belonged to the genus Glomus and genus Acaulospora , accounting for more than half of the species and relative abundance found on trees roots and over 95% of spore density across all sites. Greater AMF diversity correlated with lower soil organic matter, carbon, and nitrogen concentrations and longer durations of prior pasture use across sites. Contrary to previous literature findings, AMF species diversity and spore densities were inversely related to tree growth, which may have arisen from trees facultatively increasing their associations with AMF in lower soil fertility sites. Changes to AMF community composition also may have led to variation in disturbance susceptibility, host tree nutrient acquisition, and tree growth. These results highlight the potential importance of fungal-tree-soil interactions in forest recovery and suggest that fungal community dynamics could have important implications for tree growth in disturbed soils.

  2. Influence of arbuscular mycorrhizal fungi, rhizobium inoculation and rock phosphate on growth and quality of lentil

    International Nuclear Information System (INIS)

    Yaseen, T.; Ali, K.

    2016-01-01

    Effective inoculation of legumes has the ability not only to ensure nutrients availability to plants particularly in N and P-limiting (due to improvement in nutrients fixation) environments but also can manipulate the environmental hazards associated with over inorganic fertilization. To support this view, the current experiment was conducted to study the influence of rock phosphorus fertilization, Arbuscular Mycorrhizae (AM) and Rhizobium inoculation on growth and yield parameters of Lens culinaris (NARC.2008-4). In addition, the current experiments aimed to evaluate the effect of different inoculation practices on crop quality in comparison with control (no inoculation).The experiment was laid out in randomized complete block design with four replications during winter (2010-11 and 2012-13) at the Department of Botany University of Peshawar Pakistan. Overall, inoculated plant performed superior in terms of plant growth and quality over control. All plants measured parameters (Leaf chlorophyll content, seed protein, fiber and ash content, plant height, number of seed pod-1, leaves plant-1, flowers plant-1, pods plant-1, pod length and thousand seed weight) were highest in plant samples inoculated with VAM and Rhizobium in combination as compared to sole application of VAM or Rhizobium. Combined inoculation of VAM and Rhizobium caused 10, 24, 17, 21 and 14% increase in seed protein content, leaf chlorophyll content, seed fiber content, seed ash content and number of seed pod-1 over sole application of VAM and Rhizobium when averaged over two years. Combined application of Rhizobium + VAM enhanced seed yield plant-1 by 45% over control and 24% and 28% over sole inoculation of VAM and Rhizobium respectively. It is therefore concluded that dual inoculation of VAM + Rhizobium and rock phosphate may be of only limited consequence in high input agricultural systems. (author)

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

    DEFF Research Database (Denmark)

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

    1998-01-01

    (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...

  4. Effectiveness of cow manure and mycorrhiza on the growth of soybean

    Science.gov (United States)

    Muktiyanta, M. N. A.; Samanhudi; Yunus, A.; Pujiasmanto, B.; Minardi, S.

    2018-03-01

    Soybean is one of the major food crop commodities in Indonesia. The needs of soybean each year is always increasing, but the the production rate is low. The research aimed to know the influence of treatment doses of cow manure and mycorrhiza towards growth and yield of soybeans. This research was conducted using Randomized Complete Block Design with two factors. The first factor is the dose of cow manure: S0 (0 g/plot), S1 (781.25 g/plot), S2 (1562.5 g/plot), and S3 (2343.75 g/plot). The second factor is the dose of mycorrhiza: M0 (0 g/plot), M1 (100 g/plot), and M2 (200 g/plot). The observed parameters is plant height, the number of productive branches, weight of 100 seeds, root length, fresh weight of biomass, dry weight of biomass, conversion calculation results of soybeans per hectacre and the percentage of roots infected with mycorrhiza. Data were analyzed with ANOVA at 5% significance level, continued with Duncan test at 5% confidence level. The results showed that no interaction between the two treatments. Doses of cow manure provides significant influence to plant height and the length of the root. Whereas, the doses of mycorrhiza provides significant effect to the number of productive branch, weight of 100 seeds, dry weight of biomass, and the conversion of soybean yield per hectare.

  5. 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...

  6. Vertical distribution and temperature relations of sheathing mycorrhizas of Betula spp. growing on coal spoil

    Energy Technology Data Exchange (ETDEWEB)

    Ingleby, K.; Last, F.T.; Mason, P.A.

    1985-10-01

    Naturally-occurring fine roots (<2 mm dia.) of Betula spp. were sampled to a depth of 30 cm at seven locations on each of two transects across a heap of coal spoil in parts subject to after-burn. In the top 20 cm of substrate, 87% of the root pieces occurred. Irrespective of depth, sheathing mycorrhizas were found on 83% of the roof pieces. While the percentages of Paxillus-type mycorrhizas decreased with soil depth, those of a Scleroderma-type significantly increased. Total numbers of mycorrhizas counted at the end-of-season were independent of substrate temperatures. However, numbers of Paxillus-type mycorrhizas were inversely related to both annual mean and spring substrate temperatures, whereas those of the Scleroderma- type were directly related. Vegetative cultures of Scleroderma citrinum grew on an agar medium at 30 C, whereas those of Paxillus involutus did not; at lower temperatures the two fungi responded similarly to temperature changes. The evidence suggests that the observed patterns of mycorrhizal development reflect the changing competitive abilities of Scleroderma and Paxillus and/or host influences at different temperatures in the range 8-16 C.

  7. 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...

  8. 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.

  9. The mycorrhiza-dependent defensin MtDefMd1 of Medicago truncatula acts during the late restructuring stages of arbuscule-containing cells.

    Directory of Open Access Journals (Sweden)

    Marian Uhe

    Full Text Available Different symbiotic and pathogenic plant-microbe interactions involve the production of cysteine-rich antimicrobial defensins. In Medicago truncatula, the expression of four MtDefMd genes, encoding arbuscular mycorrhiza-dependent defensins containing an N-terminal signal peptide and exhibiting some differences to non-symbiotic defensins, raised over the time of fungal colonization. Whereas the MtDefMd1 and MtDefMd2 promoters were inactive in cells containing young arbuscules, cells with fully developed arbuscules displayed different levels of promoter activities, indicating an up-regulation towards later stages of arbuscule formation. MtDefMd1 and MtDefMd2 expression was absent or strongly down-regulated in mycorrhized ram1-1 and pt4-2 mutants, known for defects in arbuscule branching or premature arbuscule degeneration, respectively. A ~97% knock-down of MtDefMd1/MtDefMd2 expression did not significantly affect arbuscule size. Although overexpression of MtDefMd1 in arbuscule-containing cells led to an up-regulation of MtRam1, encoding a key transcriptional regulator of arbuscule formation, no morphological changes were evident. Co-localization of an MtDefMd1-mGFP6 fusion with additional, subcellular markers revealed that this defensin is associated with arbuscules in later stages of their life-cycle. MtDefMd1-mGFP6 was detected in cells with older arbuscules about to collapse, and ultimately in vacuolar compartments. Comparisons with mycorrhized roots expressing a tonoplast marker indicated that MtDefMd1 acts during late restructuring processes of arbuscule-containing cells, upon their transition into a post-symbiotic state.

  10. 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...... 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...

  11. Vesicular thick-walled swollen hyphae in pulmonary zygomycosis.

    Science.gov (United States)

    Kimura, Masatomo; Ito, Hiroyuki

    2009-03-01

    An autopsy case of pulmonary zygomycosis in a patient with rheumatoid arthritis on immunosuppressive therapy is presented herein. There was a pulmonary cavitated infarct caused by mycotic thrombosis. Thin-walled narrow hyphae and vesicular thick-walled swollen hyphae were found on the pleural surface and in the necrotic tissue at the periphery of the cavity. Findings of such shaped fungal elements may cause erroneous histopathological diagnosis because pauciseptate broad thin-walled hyphae are usually the only detectable fungal elements in zygomycosis tissue. Although immunohistochemistry confirmed these unusual elements to be zygomycetous in the present case, it is important for the differential diagnosis to be aware that zygomycetes can form thin narrow hyphae and vesicular thick-walled swollen hyphae.

  12. An Atypical Local Vesicular Reaction to the Yellow Fever Vaccine

    OpenAIRE

    Wauters, Robert H.; Hernandez, Camellia L.; Petersen, Maureen M.

    2017-01-01

    Yellow fever vaccine is a live attenuated viral inoculation indicated for patients traveling to endemic areas. The vaccine is generally well tolerated with minimal adverse effects. Typical side effects include malaise, pain at the injection site, and, albeit rarely, immediate hypersensitivity reactions. We present a case of a rare adverse reaction to yellow fever vaccine in which a patient developed vesicular lesions resulting in bullae and circumferential hyperpigmentation.

  13. An Atypical Local Vesicular Reaction to the Yellow Fever Vaccine.

    Science.gov (United States)

    Wauters, Robert H; Hernandez, Camellia L; Petersen, Maureen M

    2017-09-19

    Yellow fever vaccine is a live attenuated viral inoculation indicated for patients traveling to endemic areas. The vaccine is generally well tolerated with minimal adverse effects. Typical side effects include malaise, pain at the injection site, and, albeit rarely, immediate hypersensitivity reactions. We present a case of a rare adverse reaction to yellow fever vaccine in which a patient developed vesicular lesions resulting in bullae and circumferential hyperpigmentation.

  14. Role of arbuscular mycorrhizal fungi in phytoremediation of heavy ...

    African Journals Online (AJOL)

    sadia

    2016-05-18

    May 18, 2016 ... Sciences, Quaid-i-Azam University, Islamabad, Pakistan. Received 19 ... weeks of pot experiment, roots colonization, shoot and root biomass, growth, heavy metals contents ... using arbuscular mycorrhizal fungi (AMF) in soil.

  15. Composition of arbuscular mycorrhizal fungi associated with cassava

    African Journals Online (AJOL)

    SARAH

    2016-02-29

    Feb 29, 2016 ... Objectives: Arbuscular mycorrhizal fungi (AMF) form root symbiotic relationships with higher plants, but .... including growth habit of stem, stem colour, outer and inner root ..... of AM fungi to colonize roots, breaking down their.

  16. Inoculation of Ceratonia siliqua L. with native arbuscular mycorrhizal ...

    African Journals Online (AJOL)

    Inoculation of Ceratonia siliqua L. with native arbuscular mycorrhizal fungi mixture improves seedling establishment under greenhouse conditions. Ouahmane Lahcen, Ndoye Ibrahima, Morino Abdessadek, Ferradous Abderrahim, Sfairi Youssef, Al Faddy Mohamed Najib, Abourouh Mohamed ...

  17. Host plant quality mediates competition between arbuscular mycorrhizal fungi

    NARCIS (Netherlands)

    Knegt, B.; Jansa, J.; Franken, O.; Engelmoer, D.J.P.; Werner, G.D.A.; Bücking, H.; Kiers, E.T.

    2016-01-01

    Arbuscular mycorrhizal fungi exchange soil nutrients for carbon from plant hosts. Empirical works suggests that hosts may selectively provide resources to different fungal species, ultimately affecting fungal competition. However, fungal competition may also be mediated by colonization strategies of

  18. Molecular trait indicators: Moving beyond phylogeny in arbuscular mycorrhizal ecology

    NARCIS (Netherlands)

    Gamper, H.A.; van der Heijden, M.; Kowalchuk, G.A.

    2010-01-01

    Arbuscular mycorrhizal (AM) fungi form symbiotic associations with the roots of most plants, thereby mediating nutrient and carbon fluxes, plant performance, and ecosystem dynamics. Although considerable effort has been expended to understand the keystone ecological position of AM symbioses, most

  19. Diversity and biogeography of arbuscular mycorrhizal fungi in agricultural soils

    Czech Academy of Sciences Publication Activity Database

    Oehl, F.; Laczko, E.; Oberholzer, H.-R.; Jansa, Jan; Egli, S.

    2017-01-01

    Roč. 53, č. 7 (2017), s. 777-797 ISSN 0178-2762 Institutional support: RVO:61388971 Keywords : Arbuscular mycorrhizal * Agriculture * Biodiversity Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 3.683, year: 2016

  20. Mycorrhizae Alter Toxin Sequestration and Performance of Two Specialist Herbivores

    Directory of Open Access Journals (Sweden)

    Amanda R. Meier

    2018-04-01

    Full Text Available Multitrophic species interactions are shaped by both top-down and bottom-up factors. Belowground symbionts of plants, such as arbuscular mycorrhizal fungi (AMF, can alter the strength of these forces by altering plant phenotype. For example, AMF-mediated changes in foliar toxin and nutrient concentrations may influence herbivore growth and fecundity. In addition, many specialist herbivores sequester toxins from their host plants to resist natural enemies, and the extent of sequestration varies with host plant secondary chemistry. Therefore, by altering plant phenotype, AMF may affect both herbivore performance and their resistance to natural enemies. We examined how inoculation of plants with AMF influences toxin sequestration and performance of two specialist herbivores feeding upon four milkweed species (Asclepias incarnata, A. curassavica, A. latifolia, A. syriaca. We raised aphids (Aphis nerii and caterpillars (Danaus plexippus on plants for 6 days in a fully factorial manipulation of milkweed species and level of AMF inoculation (zero, medium, and high. We then assessed aphid and caterpillar sequestration of toxins (cardenolides and performance, and measured defensive and nutritive traits of control plants. Aphids and caterpillars sequestered higher concentrations of cardenolides from plants inoculated with AMF across all milkweed species. Aphid per capita growth rates and aphid body mass varied non-linearly with increasing AMF inoculum availability; across all milkweed species, aphids had the lowest performance under medium levels of AMF availability and highest performance under high AMF availability. In contrast, caterpillar survival varied strongly with AMF availability in a plant species-specific manner, and caterpillar growth was unaffected by AMF. Inoculation with AMF increased foliar cardenolide concentrations consistently among milkweed species, but altered aboveground biomasses and foliar phosphorous concentrations in a plant

  1. Fungos micorrízicos arbusculares e adubação fosfatada em mudas de mangabeira Arbuscular mycorrhizal fungi and phosphorus supply on seedlings of mangabeira

    Directory of Open Access Journals (Sweden)

    Cynthia Maria Carneiro Costa

    2005-03-01

    Full Text Available O objetivo deste trabalho foi avaliar os efeitos de fungos micorrízicos arbusculares (FMA e da adubação fosfatada em mudas de mangabeira (Hancornia speciosa Gomes. O experimento, em casa de vegetação, utilizou delineamento inteiramente casualizado em fatorial com dois tratamentos de solo nativo oriundo de pomar com mangabeiras, desinfestado com brometo de metila e não-desinfestado, seis doses de P (3*, 3, 48, 93, 138 e 183 mg dm-3 e três tratamentos de inoculação, Gigaspora albida Schenck & Smith, Glomus etunicatum Becker & Gerdemann e controle sem inoculação, com quatro repetições. O tratamento 3* não recebeu solução nutritiva e os demais receberam solução nutritiva de Hoagland sem fósforo por ocasião da inoculação. Após 150 dias, observou-se aumento na altura, biomassa e área foliar nos tratamentos com G. albida, em solo desinfestado. Respostas à inoculação ocorreram nas mudas cultivadas com a menor dose de P, nos dois tratamentos de solo. A mangabeira mostrou-se dependente da micorrização apenas na menor dose de P em solo desinfestado. Nos demais níveis de P, a dependência variou em função do FMA e da condição do solo. A associação com G. albida proporcionou melhor desenvolvimento das mudas de mangabeira.The objective of this work was to evaluate the effects of the association of arbuscular mycorrhizal fungi (AMF and phosphorus fertilization on seedlings of "mangaba" (Hancornia speciosa. The experiment, at a greenhouse, was in a completely randomized factorial design with two treatments of the native soil from an H. speciosa orchard, fumigated with methyl bromite and non-fumigated, six doses of P (3*, 3, 48, 93, 138 and 183 mg dm-3 and three inoculation treatments, Gigaspora albida Schenck & Smith, Glomus etunicatum Becker & Gerdemann and an uninoculated control, with four replicates. The treatment 3* did not receive nutrient solution and the others received Hoagland nutrient solution without phosphorus

  2. 134Cs in heather seed plants grown with and without mycorrhiza

    International Nuclear Information System (INIS)

    Strandberg, M.; Johansson, M.

    1988-01-01

    Experiments were carried out to determine differences between mycorrhized and non-mycorrhized seed plants of heather, Calluna vulgaris(L)Hull, as regards the uptake of 134 Cs. In most treatments heather with mycorrhiza had a significantly higher transfer of 134 Cs to the shoots than heather without mycorrhiza. As an average the concentration of 134 Cs was 18% higher in the mycorrhized plants than in the non-mycorrhized. Application of 10 kg K/ha reduced the concentration of 134 Cs in shoots of heather by 49% as an average. Because of improved growth in the potassium fertilized pots the reduction viewed on the basis of the area was only 33%. Nitrogen application does not significantly influence the concentration of 134 Cs in shoots of heather regardless of mycorrhizal status. (Copyright (c) 1988 Elsevier Science B.V., Amsterdam. All rights reserved.)

  3. {sup 134}Cs in heather seed plants grown with and without mycorrhiza

    Energy Technology Data Exchange (ETDEWEB)

    Strandberg, M. [Risoe National Laboratory, DK-4000 Roskilde (Denmark); Johansson, M. [Department of Mycology, Botanical Institute, University of Copenhagen, Oester Farimagsgade 2D, DK-1353 Copenhagen K. (Denmark)

    1988-08-01

    Experiments were carried out to determine differences between mycorrhized and non-mycorrhized seed plants of heather, Calluna vulgaris(L)Hull, as regards the uptake of {sup 134}Cs. In most treatments heather with mycorrhiza had a significantly higher transfer of {sup 134}Cs to the shoots than heather without mycorrhiza. As an average the concentration of {sup 134}Cs was 18% higher in the mycorrhized plants than in the non-mycorrhized. Application of 10 kg K/ha reduced the concentration of {sup 134}Cs in shoots of heather by 49% as an average. Because of improved growth in the potassium fertilized pots the reduction viewed on the basis of the area was only 33%. Nitrogen application does not significantly influence the concentration of {sup 134}Cs in shoots of heather regardless of mycorrhizal status. (Copyright (c) 1988 Elsevier Science B.V., Amsterdam. All rights reserved.)

  4. Effects of water deficit and mycorrhizae on grain yield, reproductive and physiological traits of corn hybrids

    Directory of Open Access Journals (Sweden)

    Mikail Nordokht

    2018-06-01

    Full Text Available Increasing crop production to ensure future food security while reducing environmental pressure on agro-ecosystems requires improved water and nutrient use efficiency. the arid and semiarid regions of the world lack of sufficient water supply is the major problem for corn cultivation and is a restriction for its production, so studies on the growth limitation and germination of corn seeds under drought conditions seems very necessary. The effects of drought on plant growth depend on several factors such as plant genetic resistance, stage of growth and duration of plant expose to drought. The AMF are playing a vital role in sustainable agriculture because they enhance plant water relations, which improve the drought resistance of host plants. It is important to increase our understanding of AM fungal and maize genotype interactions and water condition on the symbiosis, and on the physiology and nutritional status of maize plants. Thus Mycorrhizae application and choosing suitable cultivar are of simple managements in decreasing drought effect. This investigation had done in order to investigate effect of irrigation regimes (irrigation after 70, 110 and 150 mm evaporaation from evaporate basin, Mycorrhizae (non application and application of Mycorrhizae and cultivar (704 and 640 on growth and yield of maize. A split factorial experiment based on randomized complete block design with three replications was conducted during growing season of 2015 at Islamic Azad University, Malekan Branch, Plots were then furrow irrigated in the mornings every week. Each block was including 12 plots. The size of each plot was 3.5m×4m, and there was in each plot, 5 rows with a distance of 75 cm, and the length of 4 m. The distance between plots was selected 150 cm, and the distance between blocks was selected 3 m. By mid August an area of 2.5 m from 3 line of plot area was separately harvested and traits were evaluated. MSTAT-C and EXCEL were used to analyze data

  5. Impact of soil salinity on arbuscular mycorrhizal fungi biodiversity and microflora biomass associated with Tamarix articulata Vahll rhizosphere in arid and semi-arid Algerian areas.

    Science.gov (United States)

    Bencherif, Karima; Boutekrabt, Ammar; Fontaine, Joël; Laruelle, Fréderic; Dalpè, Yolande; Sahraoui, Anissa Lounès-Hadj

    2015-11-15

    Soil salinization is an increasingly important problem in many parts of the world, particularly under arid and semi-arid areas. Unfortunately, the knowledge about restoration of salt affected ecosystems using mycorrhizae is limited. The current study aims to investigate the impact of salinity on the microbial richness of the halophytic plant Tamarix articulata rhizosphere. Soil samples were collected from natural sites with increasing salinity (1.82-4.95 ds.m(-1)). Six arbuscular mycorrhizal fungi (AMF) species were isolated from the different saline soils and identified as Septoglomus constrictum, Funneliformis mosseae, Funneliformis geosporum, Funneliformis coronatum, Rhizophagus fasciculatus, and Gigaspora gigantea. The number of AMF spores increased with soil salinity. Total root colonization rate decreased from 65 to 16% but remained possible with soil salinity. Microbial biomass in T. articulata rhizosphere was affected by salinity. The phospholipid fatty acids (PLFA) C16:1ω5 as well as i15:0, a15:0, i16:0, i17:0, a17:0, cy17:0, C18:1ω7 and cy19:0 increased in high saline soils suggesting that AMF and bacterial biomasses increased with salinity. In contrast, ergosterol amount was negatively correlated with soil salinity indicating that ectomycorrhizal and saprotrophic fungal biomasses were reduced with salinity. Our findings highlight the adaptation of arbuscular and bacterial communities to natural soil salinity and thus the potential use of mycorrhizal T. articulata trees as an approach to restore moderately saline disturbed arid lands. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Seasonal dynamics in arbuscular mycorrhizal fungal colonization and spore numbers in the rhizosphere of dactylis glomerata l. and trifolium repens L

    International Nuclear Information System (INIS)

    Xin, G.; Ye, S.; Wang, Y.; Wu, E.; Sugawara, K.

    2012-01-01

    The seasonal dynamics in the colonization of the rhizosphere of orchardgrass (Dactylis glomerata L.) and white clover (Trifolium repens L.) pastures by arbuscular mycorrhizal (AM) fungi and the production of spores in an artifical Japanese grassland was investigated over 12 months (between December 2001 and December 2002). The results showed that the AM fungal colonization fluctuated seasonally in the rhizosphere of both pastures. The total AM fungal colonization of the two pastures decreased during winter, then increased from March to June as the pastures grew, but slightly decreased again in July and August, and again followed an increase in September. There was significant difference of the colonization by arbuscules and vesicles between the two pastures ( p <0.05). Besides, the vesicular colonization of orchardgrass was higher than that of white clover, but the opposite trend was observed for arbuscular colonization. Similarly, the numbers of AM fungal spores in the pastures varied throughout the year, decreasing from spring to summer, then slowly increasing in late summer, reaching peak levels in winter. There is significant correlation between the frequency of spores in the rhizosphere soil and both soil temperature and pH. (author)

  7. 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

  8. Desenvolvimento Vegetativo e morfologia radicular de citrange carrizo afetado por ácido indolbutírico e micorrizas arbusculares Vegetative development and root morphology of carrizo citrange affected by indolebutyric acid and arbuscular mycorrhizal fungi

    Directory of Open Access Journals (Sweden)

    Paulo Vitor Dutra de Souza

    2000-04-01

    Full Text Available Este estudo foi realizado na localidade de Alcanar (Tarragona, Espanha e objetivou avaliar o efeito de cinco concentrações do ácido indolbutírico (AIB (0,0; 0,5; 1,0; 1,5; 2,0 g/L e da inoculação com micorrizas arbusculares (MA (Glomus intraradices Schenck & Smith sobre o desenvolvimento vegetativo, conteúdo foliar de P e K e morfologia radicular de plântulas de citrange Carrizo (Citrus sinensis (L. X Poncirus trifoliata (L. Raf.. Utilizou-se o delineamento experimental de blocos completos casualisados em esquema fatorial, com 4 repetições e 10 plantas por parcela. A aplicação de AIB não alterou o desenvolvimento vegetativo das plântulas cultivadas em ausência de MA, apesar de haver incrementado a quantidade de P e K e a espessura dos feixes vasculares. As MA incrementaram o conteúdo de P foliar. Encontrou-se uma interação positiva entre o AIB e as MA, pois as plântulas micorrizadas apresentaram um incremento no desenvolvimento vegetativo, nos conteúdos foliares de P e K e na espessura dos feixes vasculares com o aumento das concentrações de AIB.This study was carried out in Alcanar (Tarragona - Spain to evaluate the effect of five indolebutyric acid (IBA concentrations (0.0; 0.5; 1.0; 1.5; 2.0 g/L and inoculation with arbuscular mycorrhizae fungi (AMF (Glomus intraradices Schenck & Smith on Carrizo citrange (Citrus sinensis (L. x Poncirus trifoliata (L. Raf. vegetative development, P and K foliar contents and root morphology. The experimental design was in a Completly Randomized Block Design with 10 seedlings per plot and 4 replicates. The IBA concentrations had no effect on vegetative development of nonmycorrhizal seedlings, althougt it had increased P and K foliar contents and primary xylem tickness. AMF increased P foliar content. IBA x AMF interaction was observed, increasing IBA concentrations on mycorrhizal seedlings resulted in increased in vegetative development, P and K foliar contents and primary xylem thickness.

  9. 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.

  10. Distribution of vesicular glutamate transporters in the human brain

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    Erika eVigneault

    2015-03-01

    Full Text Available Glutamate is the major excitatory transmitter in the brain. Vesicular glutamate transporters (VGLUT1-3 are responsible for uploading glutamate into synaptic vesicles. VGLUT1 and VGLUT2 are considered as specific markers of canonical glutamatergic neurons, while VGLUT3 is found in neurons previously shown to use other neurotransmitters than glutamate. Although there exists a rich literature on the localization of these glutamatergic markers in the rodent brain, little is currently known about the distribution of VGLUT1-3 in the human brain. In the present study, using subtype specific probes and antisera, we examined the localization of the three vesicular glutamate transporters in the human brain by in situ hybridization, immunoautoradiography and immunohistochemistry. We found that the VGLUT1 transcript was highly expressed in the cerebral cortex, hippocampus and cerebellum, whereas VGLUT2 mRNA was mainly found in the thalamus and brainstem. VGLUT3 mRNA was localized in scarce neurons within the cerebral cortex, hippocampus, striatum and raphe nuclei. Following immunoautoradiographic labeling, intense VGLUT1- and VGLUT2-immunoreactivities were observed in all regions investigated (cerebral cortex, hippocampus, caudate-putamen, cerebellum, thalamus, amygdala, substantia nigra, raphe while VGLUT3 was absent from the thalamus and cerebellum. This extensive mapping of VGLUT1-3 in human brain reveals distributions that correspond for the most part to those previously described in rodent brains.

  11. Chromosomal localization of the human vesicular amine transporter genes

    Energy Technology Data Exchange (ETDEWEB)

    Peter, D.; Finn, P.; Liu, Y.; Roghani, A.; Edwards, R.H.; Klisak, I.; Kojis, T.; Heinzmann, C.; Sparkes, R.S. (UCLA School of Medicine, Los Angeles, CA (United States))

    1993-12-01

    The physiologic and behavioral effects of pharmacologic agents that interfere with the transport of monoamine neurotransmitters into vesicles suggest that vesicular amine transport may contribute to human neuropsychiatric disease. To determine whether an alteration in the genes that encode vesicular amine transport contributes to the inherited component of these disorders, the authors have isolated a human cDNA for the brain transporter and localized the human vesciular amine transporter genes. The human brain synaptic vesicle amine transporter (SVAT) shows unexpected conservation with rat SVAT in the regions that diverge extensively between rat SVAT and the rat adrenal chromaffin granule amine transporter (CGAT). Using the cloned sequences with a panel of mouse-human hybrids and in situ hybridization for regional localization, the adrenal CGAT gene (or VAT1) maps to human chromosome 8p21.3 and the brain SVAT gene (or VAT2) maps to chromosome 10q25. Both of these sites occur very close to if not within previously described deletions that produce severe but viable phenotypes. 26 refs., 3 figs., 1 tab.

  12. Effect of ryegrass (Lolium perenne L.) roots inoculation using different arbuscular mycorrhizal fungi (AMF) species on sorption of iron-cyanide (Fe-CN) complexes

    Science.gov (United States)

    Sut, Magdalena; Boldt-Burisch, Katja; Raab, Thomas

    2016-04-01

    Soils and groundwater on sites of the former Manufactured Gas Plants (MGPs) are contaminated with various complex iron-cyanides (Fe-CN). Phytoremediation is a promising tool in stabilization and remediation of Fe-CN affected soils, however, it can be a challenging task due to extreme adverse and toxic conditions. Phytoremediation may be enhanced via rhizosphere microbial activity, which can cooperate on the degradation, transformation and uptake of the contaminants. Recently, increasing number of scientist reports improved plants performance in the removal of toxic compounds with the support of arbuscular mycorrhizae fungi (AMF). Series of batch experiments using potassium hexacyanoferrate (II) solutions, in varying concentrations, were used to study the effect of ryegrass roots (Lolium perenne L.) inoculation with Rhizophagus irregularis and a mixture of Rhizophagus irregularis, Funneliformis mosseae, Rhizophagus aggregatus, and Claroideoglomus etunicatum on Fe-CN sorption. Results indicated significantly higher colonization of R. irregularis than for the mixture of AMF species on ryegrass roots. Sorption experiments revealed significantly higher reduction of total CN and free CN content in the mycorrhizal roots, indicating greater cyanide decrease in the treatment inoculated with R. irregularis. Our study indicates contribution of AM fungi in phytoremediation of Fe-CN contaminated soil.

  13. Herbivore removal reduces influence of arbuscular mycorrhizal fungi on plant growth and tolerance in an East African savanna.

    Science.gov (United States)

    González, Jonathan B; Petipas, Renee H; Franken, Oscar; Kiers, E Toby; Veblen, Kari E; Brody, Alison K

    2018-05-01

    The functional relationship between arbuscular mycorrhizal fungi (AMF) and their hosts is variable on small spatial scales. Here, we hypothesized that herbivore exclusion changes the AMF community and alters the ability of AMF to enhance plant tolerance to grazing. We grew the perennial bunchgrass, Themeda triandra Forssk in inoculum from soils collected in the Kenya Long-term Exclosure Experiment where treatments representing different levels of herbivory have been in place since 1995. We assessed AMF diversity in the field, using terminal restriction fragment length polymorphism and compared fungal diversity among treatments. We conducted clipping experiments in the greenhouse and field and assessed regrowth. Plants inoculated with AMF from areas accessed by wild herbivores and cattle had greater biomass than non-inoculated controls, while plants inoculated with AMF from where large herbivores were excluded did not benefit from AMF in terms of biomass production. However, only the inoculation with AMF from areas with wild herbivores and no cattle had a positive effect on regrowth, relative to clipped plants grown without AMF. Similarly, in the field, regrowth of plants after clipping in areas with only native herbivores was higher than other treatments. Functional differences in AMF were evident despite little difference in AMF species richness or community composition. Our findings suggest that differences in large herbivore communities over nearly two decades has resulted in localized, functional changes in AMF communities. Our results add to the accumulating evidence that mycorrhizae are locally adapted and that functional differences can evolve within small geographical areas.

  14. Improvement of Verticillium Wilt Resistance by Applying Arbuscular Mycorrhizal Fungi to a Cotton Variety with High Symbiotic Efficiency under Field Conditions

    Science.gov (United States)

    Zhang, Qiang; Gao, Xinpeng; Ren, Yanyun; Ding, Xinhua; Qiu, Jiajia; Li, Ning; Zeng, Fanchang

    2018-01-01

    Arbuscular mycorrhizal fungi (AMF) play an important role in nutrient cycling processes and plant stress resistance. To evaluate the effect of Rhizophagus irregularis CD1 on plant growth promotion (PGP) and Verticillium wilt disease, the symbiotic efficiency of AMF (SEA) was first investigated over a range of 3% to 94% in 17 cotton varieties. The high-SEA subgroup had significant PGP effects in a greenhouse. From these results, the highest-SEA variety of Lumian 1 was selected for a two-year field assay. Consistent with the performance from the greenhouse, the AMF-mediated PGP of Lumian 1 also produced significant results, including an increased plant height, stem diameter, number of petioles, and phosphorus content. Compared with the mock treatment, AMF colonization obviously inhibited the symptom development of Verticillium dahliae and more strongly elevated the expression of pathogenesis-related genes and lignin synthesis-related genes. These results suggest that AMF colonization could lead to the mycorrhiza-induced resistance (MIR) of Lumian 1 to V. dahliae. Interestingly, our results indicated that the AMF endosymbiont could directly inhibit the growth of phytopathogenic fungi including V. dahliae by releasing undefined volatiles. In summary, our results suggest that stronger effects of AMF application result from the high-SEA. PMID:29342876

  15. Mixed arbuscular mycorrhizal (AM) fungal application to improve growth and arsenic accumulation of Pteris vittata (As hyperaccumulator) grown in As-contaminated soil.

    Science.gov (United States)

    Leung, H M; Leung, A O W; Ye, Z H; Cheung, K C; Yung, K K L

    2013-08-01

    A greenhouse pot experiment was conducted to study the effects of three types of single inoculum [indigenous mycorrhizas (IM) isolated from As mine, Glomus mosseae (GM) and Glomus intraradices (GI)] and two types of mixed inoculum (mixed with IM and either GM or GI) on the growth response of Pteris vittata (hyperaccumulator) and Cynodon dactylon (non-hyperaccumulator) at three levels of As concentrations (0, 100 and 200mgkg(-1)). Both mycorrhizal plants exhibited significantly higher biomass, and N and P accumulation in its tissue than the control. Among the mycorrhizal inoculum, the mixed inoculum IM/GM promoted substantially higher mycorrhizal colonization and arsenate reductase activity in P. vittata than C. dactylon, among all As levels. The portion of Paris arbuscular mycorrhizal structure (observed in colonized roots) together with the highest As translocation factor of 10.2 in P. vittata inoculated with IM/GM was also noted. It was deduced that IM/GM inoculum may be the best choice for field inoculation at any contaminated lands as the inoculum exhibited better adaptation to variable environmental conditions and hence benefited the host plants. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  16. Improvement of Verticillium Wilt Resistance by Applying Arbuscular Mycorrhizal Fungi to a Cotton Variety with High Symbiotic Efficiency under Field Conditions

    Directory of Open Access Journals (Sweden)

    Qiang Zhang

    2018-01-01

    Full Text Available Arbuscular mycorrhizal fungi (AMF play an important role in nutrient cycling processes and plant stress resistance. To evaluate the effect of Rhizophagus irregularis CD1 on plant growth promotion (PGP and Verticillium wilt disease, the symbiotic efficiency of AMF (SEA was first investigated over a range of 3% to 94% in 17 cotton varieties. The high-SEA subgroup had significant PGP effects in a greenhouse. From these results, the highest-SEA variety of Lumian 1 was selected for a two-year field assay. Consistent with the performance from the greenhouse, the AMF-mediated PGP of Lumian 1 also produced significant results, including an increased plant height, stem diameter, number of petioles, and phosphorus content. Compared with the mock treatment, AMF colonization obviously inhibited the symptom development of Verticillium dahliae and more strongly elevated the expression of pathogenesis-related genes and lignin synthesis-related genes. These results suggest that AMF colonization could lead to the mycorrhiza-induced resistance (MIR of Lumian 1 to V. dahliae. Interestingly, our results indicated that the AMF endosymbiont could directly inhibit the growth of phytopathogenic fungi including V. dahliae by releasing undefined volatiles. In summary, our results suggest that stronger effects of AMF application result from the high-SEA.

  17. Interactions between the arbuscular mycorrhizal (AM) fungus Glomus intraradices and nontransformed tomato roots of either wild-type or AM-defective phenotypes in monoxenic cultures.

    Science.gov (United States)

    Bago, Alberto; Cano, Custodia; Toussaint, Jean-Patrick; Smith, Sally; Dickson, Sandy

    2006-09-01

    Monoxenic symbioses between the arbuscular mycorrhizal (AM) fungus Glomus intraradices and two nontransformed tomato root organ cultures (ROCs) were established. Wild-type tomato ROC from cultivar "RioGrande 76R" was employed as a control for mycorrhizal colonization and compared with its mutant line (rmc), which exhibits a highly reduced mycorrhizal colonization (rmc) phenotype. Structural features of the two root lines were similar when grown either in soil or under in vitro conditions, indicating that neither monoxenic culturing nor the rmc mutation affected root development or behavior. Colonization by G. intraradices in monoxenic culture of the wild-type line was low (<10%) but supported extensive development of extraradical mycelium, branched absorbing structures, and spores. The reduced colonization of rmc under monoxenic conditions (0.6%) was similar to that observed previously in soil. Extraradical development of runner hyphae was low and proportional to internal colonization. Few spores were produced. These results might suggest that carbon transfer may be modified in the rmc mutant. Our results support the usefulness of monoxenically obtained mycorrhizas for investigation of AM colonization and intraradical symbiotic functioning.

  18. A Mycorrhizal-Specific Ammonium Transporter from Lotus japonicus Acquires Nitrogen Released by Arbuscular Mycorrhizal Fungi1

    Science.gov (United States)

    Guether, Mike; Neuhäuser, Benjamin; Balestrini, Raffaella; Dynowski, Marek; Ludewig, Uwe; Bonfante, Paola

    2009-01-01

    In mycorrhizal associations, the fungal partner assists its plant host by providing nitrogen (N) in addition to phosphate. Arbuscular mycorrhizal (AM) fungi have access to inorganic or organic forms of N and translocate them via arginine from the extra- to the intraradical mycelium, where the N is transferred to the plant without any carbon skeleton. However, the molecular form in which N is transferred, as well as the involved mechanisms, is still under debate. NH4+ seems to be the preferential transferred molecule, but no plant ammonium transporter (AMT) has been identified so far. Here, we offer evidence of a plant AMT that is involved in N uptake during mycorrhiza symbiosis. The gene LjAMT2;2, which has been shown to be the highest up-regulated gene in a transcriptomic analysis of Lotus japonicus roots upon colonization with Gigaspora margarita, has been characterized as a high-affinity AMT belonging to the AMT2 subfamily. It is exclusively expressed in the mycorrhizal roots, but not in the nodules, and transcripts have preferentially been located in the arbusculated cells. Yeast (Saccharomyces cerevisiae) mutant complementation has confirmed its functionality and revealed its dependency on acidic pH. The transport experiments using Xenopus laevis oocytes indicated that, unlike other plant AMTs, LjAMT2;2 transports NH3 instead of NH4+. Our results suggest that the transporter binds charged ammonium in the apoplastic interfacial compartment and releases the uncharged NH3 into the plant cytoplasm. The implications of such a finding are discussed in the context of AM functioning and plant phosphorus uptake. PMID:19329566

  19. Arbuscular mycorrhizal fungi and Pseudomonas in reduce drought stress damage in flax (Linum usitatissimum L.): a field study.

    Science.gov (United States)

    Rahimzadeh, Saeedeh; Pirzad, Alireza

    2017-08-01

    Drought stress, which is one of the most serious world environmental threats to crop production, might be compensated by some free living and symbiotic soil microorganisms. The physiological response of flax plants to inoculation with two species of arbuscular mycorrhizal (AM) fungi (Funneliformis mosseae or Rhizophagus intraradices) and a phosphate solubilizing bacterium (Pseudomonas putida P13; PSB) was evaluated under different irrigation regimes (irrigation after 60, 120, and 180 mm of evaporation from Class A pan as well-watered, mild, and severe stress, respectively). A factorial (three factors) experiment was conducted for 2 years (2014-2015) based on a randomized complete block design with three replications at Urmia University, Urmia, located at North-West of Iran (37° 39' 24.82″ N44° 58' 12.42″ E). Water deficit decreased biomass, showing that flax was sensitive to drought, and AM root colonization improved the performance of the plant within irrigation levels. In all inoculated and non-inoculated control plants, leaf chlorophyll decreased with increasing irrigation intervals. Water deficit-induced oxidative damage (hydrogen peroxide, malondialdehyde, and electrolyte leakage) were significantly reduced in dual colonized plants. All enzymatic (catalase, superoxide dismutase, glutathione reductase, and ascorbate peroxidase) and non-enzymatic (glutathione, ascorbic acid, total carotenoids) antioxidants were reduced by water-limiting irrigation. Dual inoculated plants with AM plus Pseudomonas accumulated more enzymatic and non-enzymatic antioxidants than plants with bacterial or fungal inoculation singly. Dual colonized plants significantly decreased the water deficit-induced glycine betaine and proline in flax leaves. These bacterial-fungal interactions in enzymatic and non-enzymatic defense of flax plants demonstrated equal synergism with both AM fungi species. In conclusion, increased activity of enzymatic antioxidants and higher production of non

  20. The role of arbuscular mycorrhizal fungi on the early-stage restoration of seasonally dry tropical forest in Chamela, Mexico

    Directory of Open Access Journals (Sweden)

    Pilar Huante

    2012-04-01

    Full Text Available It was evaluated the effect of two different sources of local inocula from two contrasting sites (mature forest, pasture of arbuscular mycorrhizae fungi (AMF and a non-mycorrhizal control on the plant growth of six woody species differing in functional characteristics (slow-, intermediate- and fast-growth, when introduced in a seasonally tropical dry forest (STDF converted into abandoned pasture. Six plots (12 X 12m were set as AMF inoculum source. Six replicates of six different species arranged in a Latin Square design were set in each plot. Plant height, cover area and the number of leaves produced by individual plant was measured monthly during the first growing season in each treatment. Species differed in their ability to benefit from AMF and the largest responsiveness in plant height and leaf production was exhibited by the slow-growing species Swietenia humilis, Hintonia latiflora and Cordia alliodora. At the end of the growing season (November, the plant height of the fast growing species Tabebuia donnel-smithii, Ceiba pentandra and Guazuma ulmifolia were not influenced by AMF. However, inocula of AMF increased leaf production of all plant species regardless the functional characteristics of the species, suggesting a better exploitation of above-ground space and generating a light limited environment under the canopy, which contributed to pasture suppression. Inoculation of seedlings planted in abandoned pasture areas is recommended for ecological restoration due to the high responsiveness of seedling growth in most of species. Use of forest inoculum with its higher diversity of AMF could accelerate the ecological restoration of the above and below-ground comunities.

  1. Lead accumulation by jabon seedling (Anthocephalus cadamba) on tailing media with application of compost and arbuscular mycorrhizal fungi

    Science.gov (United States)

    Setyaningsih, L.; Setiadi, Y.; Budi, S. W.; Hamim; Sopandie, D.

    2017-03-01

    Lead (Pb) is one of the dangerous heavy metal contained in tailing that needs remediation activity. This study aimed to investigate the potency of jabon to take up and accumulate lead in its tissue by the application of compost and arbuscular mycorrhiza fungus (AMF) on pot observation. In Pb-containing tailing media, the average levels of Pb in roots seedling was 50% greater as compared to the levels of Pb in the stem and leaves of seedlings. Application of compost in tailings media significantly increased (p ≤ 0.5) the average levels of Pb in the roots and stems, but decreased Pb levels in leaves. Applications AMF significantly decreased (p ≤ 0.5) the average levels of Pb in the roots, stem and leaves of seedlings by approximately 18-33%. The combination applications of compost and AMF significantly (p ≤ 0.5) increased the level of Pb in the roots, stems and leaves of seedlings at 6, 16 and 27 fold respectively than that in control plant (without compost and AMF). After 12 weeks exposure, lead bioconcentration factor varied from 0.1-1.6 in seedling tissue with transport factor varied from 0.1-1.0. The application of active compost and AMF increased 1-15 fold lead accumulation from control, and the biggest accumulation was 452.9 x10-2 mg/plant with Pb concentration of 1.5 mM. Active compost and AMF application supported jabon seedling to act as lead phytostabilizer and to remove lead from the tailing to the above part of the plant.

  2. Transcriptomes of Arbuscular Mycorrhizal Fungi and Litchi Host Interaction after Tree Girdling.

    Science.gov (United States)

    Shu, Bo; Li, Weicai; Liu, Liqin; Wei, Yongzan; Shi, Shengyou

    2016-01-01

    Trunk girdling can increase carbohydrate content above the girdling site and is an important strategy for inhibiting new shoot growth to promote flowering in cultivated litchi (Litchi chinensis Sonn.). However, girdling inhibits carbohydrate transport to the root in nearly all of the fruit development periods and consequently decreases root absorption. The mechanism through which carbohydrates regulate root development in arbuscular mycorrhiza (AM) remains largely unknown. Carbohydrate content, AM colonization, and transcriptome in the roots were analyzed to elucidate the interaction between host litchi and AM fungi when carbohydrate content decreases. Girdling decreased glucose, fructose, sucrose, quebrachitol, and starch contents in the litchi mycorrhizal roots, thereby reducing AM colonization. RNA-seq achieved approximately 60 million reads of each sample, with an average length of reads reaching 100 bp. Assembly of all the reads of the 30 samples produced 671,316 transcripts and 381,429 unigenes, with average lengths of 780 and 643 bp, respectively. Litchi (54,100 unigenes) and AM fungi unigenes (33,120 unigenes) were achieved through sequence annotation during decreased carbohydrate content. Analysis of differentially expressed genes (DEG) showed that flavonoids, alpha-linolenic acid, and linoleic acid are the main factors that regulate AM colonization in litchi. However, flavonoids may play a role in detecting the stage at which carbohydrate content decreases; alpha-linolenic acid or linoleic acid may affect AM formation under the adaptation process. Litchi trees stimulated the expression of defense-related genes and downregulated symbiosis signal-transduction genes to inhibit new AM colonization. Moreover, transcription factors of the AP2, ERF, Myb, WRKY, bHLH families, and lectin genes altered maintenance of litchi mycorrhizal roots in the post-symbiotic stage for carbohydrate starvation. Similar to those of the litchi host, the E3 ubiquitin ligase complex

  3. Effect of Household Solid Waste on Initial Growth Performance of Acacia auriculiformis and Cedrela toona in Mycorrhiza Inoculated Soil

    Directory of Open Access Journals (Sweden)

    M.M. Abdullah-Al-Mamun

    2015-09-01

    Full Text Available Solid waste disposal and management became one of the major environmental concerns in Bangladesh. Realising the problem, the present study has been undertaken with a view to find a sound and effective way of bio-degradable solid waste management. The study was carried out in the nursery of Institute of Forestry and Environmental Sciences at University of Chittagong to determine the effects of solid waste and waste inoculated with mycorrhizal soil on initial growth performance of Acacia auriculiformis and Cedrela toona. Before planting the seedlings, decomposable waste and mycorrhiza inoculated decomposable waste were placed on the planting holes. Physical growth parameters of seedlings (shoot and root length, leaf and branch number, fresh and dry weight of shoot and root and nodulation status and the macro nutrients (N, P and K were recorded after six months of planting. The highest performance of physical parameters was recorded in the soil treated by mycorrhiza inoculated waste. Cedrela toona was represented by maximum nutrients uptake (N-2.60%, P-0.21% and K-2.34% respectively in the soil treated with mycorrhiza. In case of Acacia auriculiformis, N uptake was maximum (3.02% in control while K uptake was highest (1.27% in soil with waste and P (0.18% uptake was highest in the soil treated with mycorrhiza inoculated waste. Highest initial growth performance was revealed by seedlings treated with mycorrhiza inoculated waste. This study suggested to use mycorrhiza and waste for plantation purposes for hygienic disposal of solid waste and to reduce cost of cultivation.

  4. Communities, populations and individuals of arbuscular mycorrhizal fungi

    DEFF Research Database (Denmark)

    Rosendahl, Søren

    2008-01-01

    Arbuscular mycorrhizal fungi in the phylum Glomeromycota are found globally in most vegetation types, where they form a mutualistic symbiosis with plant roots. Despite their wide distribution, only relatively few species are described. The taxonomy is based on morphological characters...... of the asexual resting spores, but molecular approaches to community ecology have revealed a considerable unknown diversity from colonized roots. Although the lack of genetic recombination is not unique in the fungal kingdom, arbuscular mycorrhizal fungi are probably ancient asexuals. The long asexual evolution...... of the fungi has resulted in considerable genetic diversity within morphologically recognizable species, and challenges our concepts of individuals and populations. This review critically examines the concepts of species, communities, populations and individuals of arbuscular mycorrhizal fungi....

  5. Effectiveness of the application of arbuscular mycorrhiza fungi and organic amendments to improve soil quality and plant performance under stress conditions

    NARCIS (Netherlands)

    Azcón, R.; Medina, A.

    2010-01-01

    Plant growth is limited in arid and/or contaminated sites due to the adverse conditions coming from heavy metal (HM) contamination and/or water stress. Moreover, soils from these areas are generally characterised by poor soil structure, low water-holding capacity, lack of organic matter and nutrient

  6. Arbuscular mycorrhizal fungi associated with vegetation and soil parameters under rest grazing management in a desert steppe ecosystem.

    Science.gov (United States)

    Bai, Gegenbaoleer; Bao, Yuying; Du, Guoxin; Qi, Yunlong

    2013-05-01

    The impact of rest grazing on arbuscular mycorrhizal fungi (AMF) and the interactions of AMF with vegetation and soil parameters under rest grazing condition were investigated between spring and late summer in a desert steppe ecosystem with different grazing managements (rest grazing with different lengths of resting period, banned or continuous grazing) in Inner Mongolia, China. AMF diversity and colonization, vegetation biomass, soil properties and soil phosphatase activity were examined. In rest grazing areas of 60 days, AMF spore number and diversity index at a 0-10 cm soil depth as well as vesicular and hyphal colonization rates were higher compared with other grazing treatments. In addition, soil organic matter and total N contents were highest and soil alkaline phosphatase was most active under 60-day rest grazing. In August and September, these areas also had the highest amount of aboveground vegetation. The results indicated that resting grazing for an appropriate period of time in spring has a positive effect on AMF sporulation, colonization and diversity, and that under rest grazing conditions, AMF parameters are positively correlated with some soil characteristics.

  7. Metabolic control of vesicular glutamate transport and release.

    Science.gov (United States)

    Juge, Narinobu; Gray, John A; Omote, Hiroshi; Miyaji, Takaaki; Inoue, Tsuyoshi; Hara, Chiaki; Uneyama, Hisayuki; Edwards, Robert H; Nicoll, Roger A; Moriyama, Yoshinori

    2010-10-06

    Fasting has been used to control epilepsy since antiquity, but the mechanism of coupling between metabolic state and excitatory neurotransmission remains unknown. Previous work has shown that the vesicular glutamate transporters (VGLUTs) required for exocytotic release of glutamate undergo an unusual form of regulation by Cl(-). Using functional reconstitution of the purified VGLUTs into proteoliposomes, we now show that Cl(-) acts as an allosteric activator, and the ketone bodies that increase with fasting inhibit glutamate release by competing with Cl(-) at the site of allosteric regulation. Consistent with these observations, acetoacetate reduced quantal size at hippocampal synapses and suppresses glutamate release and seizures evoked with 4-aminopyridine in the brain. The results indicate an unsuspected link between metabolic state and excitatory neurotransmission through anion-dependent regulation of VGLUT activity. Copyright © 2010 Elsevier Inc. All rights reserved.

  8. ARBUSCULAR MYCORRHIZAL ASSOCIATION IN Coccothrinax readii Quero

    Directory of Open Access Journals (Sweden)

    Gerardo Emmanuel Polanco Hernández

    2013-08-01

    Full Text Available Coccothrinax readii, is a palm endemic to the Yucatan coast, its successful establishment in stressful environments suggests that factors such as mycorrhizal association may determine its success, the question arose in this work, assess environmental conditions which states and to describe their particular characteristics related to the anatomy of their roots and mycorrhizal colonization in three different seasons over a year. The study site was the coastal dune scrub of San Benito, Yucatan, where he placed a data logger that measurements performed ambient temperature (T, relative humidity (HR and photosynthethic photon flux (PPF for five days in dry, rainy and windy, also determined  the total phosphorus and extractable of the soil. The results indicate significant fluctuations of environmental variables throughout the year, on the other hand, the presence of the velamen on the roots of C. readii not restrict arbuscular mycorrhizal colonization. This association is affected by microenvironmental conditions, as during the dry season, when environmental conditions are unfavorable, the colonization percentage is higher than in the windy season, when microenvironmental conditions are more favorable.

  9. Are vesicular neurotransmitter transporters potential treatment targets for temporal lobe epilepsy?

    Directory of Open Access Journals (Sweden)

    Joeri eVan Liefferinge

    2013-08-01

    Full Text Available The vesicular neurotransmitter transporters (VNTs are small proteins responsible for packing synaptic vesicles with neurotransmitters thereby determining the amount of neurotransmitter released per vesicle through fusion in both neurons and glial cells. Each transporter subtype was classically seen as a specific neuronal marker of the respective nerve cells containing that particular neurotransmitter or structurally related neurotransmitters. More recently, however, it has become apparent that common neurotransmitters can also act as co-transmitters, adding complexity to neurotransmitter release and suggesting intriguing roles for VNTs therein. We will first describe the current knowledge on vesicular glutamate transporters (VGLUT1/2/3, the vesicular excitatory amino acid transporter (VEAT, the vesicular nucleotide transporter (VNUT, vesicular monoamine transporters (VMAT1/2, the vesicular acetylcholine transporter (VAChT and the vesicular γ-aminobutyric acid (GABA transporter (VGAT in the brain. We will focus on evidence regarding transgenic mice with disruptions in VNTs in different models of seizures and epilepsy. We will also describe the known alterations and reorganizations in the expression levels of these VNTs in rodent models for temporal lobe epilepsy (TLE and in human tissue resected for epilepsy surgery. Finally, we will discuss perspectives on opportunities and challenges for VNTs as targets for possible future epilepsy therapies.

  10. Vesicular nucleotide transporter (VNUT): appearance of an actress on the stage of purinergic signaling.

    Science.gov (United States)

    Moriyama, Yoshinori; Hiasa, Miki; Sakamoto, Shohei; Omote, Hiroshi; Nomura, Masatoshi

    2017-09-01

    Vesicular storage of ATP is one of the processes initiating purinergic chemical transmission. Although an active transport mechanism was postulated to be involved in the processes, a transporter(s) responsible for the vesicular storage of ATP remained unidentified for some time. In 2008, SLC17A9, the last identified member of the solute carrier 17 type I inorganic phosphate transporter family, was found to encode the vesicular nucleotide transporter (VNUT) that is responsible for the vesicular storage of ATP. VNUT transports various nucleotides in a membrane potential-dependent fashion and is expressed in the various ATP-secreting cells. Mice with knockout of the VNUT gene lose vesicular storage and release of ATP from neurons and neuroendocrine cells, resulting in blockage of the initiation of purinergic chemical transmission. Thus, VNUT plays an essential role in the vesicular storage and release of ATP. The VNUT knockout mice exhibit resistance for neuropathic pain and a therapeutic effect against diabetes by way of increased insulin sensitivity. Thus, VNUT inhibitors and suppression of VNUT gene expression may be used for therapeutic purposes through suppression of purinergic chemical transmission. This review summarizes the studies to date on VNUT and discusses what we have learned about the relevance of vesicular ATP release as a potential drug target.

  11. 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

  12. 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

  13. Novel root-fungus symbiosis in Ericaceae: sheathed ericoid mycorrhiza formed by a hitherto undescribed basidiomycete with affinities to Trechisporales

    Czech Academy of Sciences Publication Activity Database

    Vohník, Martin; Sadowsky, J. J.; Kohout, Petr; Lhotáková, Z.; Nestby, R.; Kolařík, Miroslav

    2012-01-01

    Roč. 7, č. 6 (2012), e39524 E-ISSN 1932-6203 R&D Projects: GA ČR GP206/09/P340 Institutional support: RVO:67985939 ; RVO:61388971 Keywords : ericoid mycorrhiza * Ericaceae * Basidiomycetes Subject RIV: EF - Botanics; EE - Microbiology, Virology (MBU-M) Impact factor: 3.730, year: 2012

  14. Mycorrhizas and soil ecosystem function of co-existing woody vegetation islands at the alpine tree line

    Czech Academy of Sciences Publication Activity Database

    Wang, L.; Otgonsuren, B.; Godbold, Douglas

    2017-01-01

    Roč. 411, 1-2 (2017), s. 467-481 ISSN 0032-079X R&D Projects: GA MŠk(CZ) LO1415 Institutional support: RVO:67179843 Keywords : Ectoenzymes * Ectomycorrhizas * Enzyme activity * Ericoid mycorrhizas * Nitrogen-mineralization Subject RIV: EF - Botanics OBOR OECD: Environmental sciences (social aspects to be 5.7) Impact factor: 3.052, year: 2016

  15. In vitro culture of arbuscular mycorrhizal fungi: advances and future ...

    African Journals Online (AJOL)

    Arbuscular mycorrhizal (AM) fungi are ecologically important for most vascular plants for their growth and survival. AM fungi are obligate symbionts. In recent years, there have been many attempts to cultivate in vitro. Some relevant results indicate efforts are not far from successful growth of AM fungi independent of a plant ...

  16. Arsenic uptake and phytoremediation potential by arbuscular mycorrhizal fungi

    Science.gov (United States)

    Xinhua He; Erik Lilleskov

    2014-01-01

    Arsenic (As) contamination of soils and water is a global problem because of its impacts on ecosystems and human health. Various approaches have been attempted for As remediation, with limited success. Arbuscular mycorrhizal (AM) fungi play vital roles in the uptake of water and essential nutrients, especially phosphorus (P), and hence enhance plant performance and...

  17. Arbuscular-mycorrhizal fungi (Glomales) in Egypt. III: Distribution ...

    African Journals Online (AJOL)

    Roots and rhizospheric soils of 26 plant species belonging to 18 families representing five different habitats at El-Omayed Biosphere Reserve were collected and examined for arbuscular-mycorrhizal fungal (AMF) associations. Plant species recorded in the habitat of coastal sand dunes had the highest percentage of ...

  18. Solanum cultivar responses to arbuscular mycorrhizal fungi: growth ...

    African Journals Online (AJOL)

    A greenhouse experiment was carried out in a sandy soil with a low available phosphorus to evaluate responsiveness of four Solanum aethiopicum cultivars to indigenous arbuscular mycorrhizal fungi. Results showed clear interaction between genetic variability of cultivars and fungal isolates on shoot biomass and on ...

  19. Effect of arbuscular mycorrhizal fungal inoculation on growth, and ...

    African Journals Online (AJOL)

    The aim of our work was to assess the effect of inoculation with three arbuscular mycorrhizal fungi (AMF) (Rhizoglomus aggregatum (N.C. Schenck and G.S. Sm.) Sieverd., G.A. Silva and Oeh., Funneliformis mosseae (T.H. Nicolson and Gerd.) C. Walker and A. Schüssler. and Rhizoglomus intraradices (N.C. Schenck and ...

  20. Studying genome heterogeneity within the arbuscular mycorrhizal fungal cytoplasm

    NARCIS (Netherlands)

    Boon, E.; Halary, S.; Bapteste, E.; Hijri, M.

    2015-01-01

    Although heterokaryons have been reported in nature, multicellular organisms are generally assumed genetically homogeneous. Here, we investigate the case of arbuscular mycorrhizal fungi (AMF) that form symbiosis with plant roots. The growth advantages they confer to their hosts are of great

  1. Arbuscular mycorrhizal fungi species associated with rhizosphere of ...

    African Journals Online (AJOL)

    A survey of arbuscular mycorrhizal fungi (AMF) diversity and date palm (Phoenix dactylifera L.) tree root colonization in arid areas was undertaken in ten palm groves located along the Ziz valley (Tafilalet, south-west Morocco). The frequency and the mean intensity of root colonization reached 72 and 43% respectively and ...

  2. Responses of soilless grown tomato plants to arbuscular ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-10-20

    Oct 20, 2008 ... Full Length Research Paper. Responses of soilless grown tomato plants to arbuscular mycorrhizal fungal (Glomus fasciculatum) colonization in re-cycling and open systems. H. Yildiz Dasgan1*, Sebnem Kusvuran1 and Ibrahim Ortas2. 1Cukurova University, Faculty of Agriculture, Department of Horticulture ...

  3. Cover cropping impacts on arbuscular mycorrhizal fungi and soil aggregation

    Science.gov (United States)

    Cover crops are a management tool which can extend the period of time that a living plant is growing and conducting photosynthesis. This is critical for soil health, because most of the soil organisms, particularly the arbuscular mycorrhizal fungi, are limited by carbon. Research, on-farm, and demon...

  4. What we know about arbuscular mycorhizal fungi and associated ...

    African Journals Online (AJOL)

    Mycorrhizal fungi are common soil microorganisms and are well known for their symbiotic association with the roots of host plants. The soil is a complex environment harbouring a wide diversity of microorganisms. The interaction between soil bacteria and arbuscular mycorrhizal fungi has been shown in several studies to ...

  5. Detection of species diversity of arbuscular mycorrhizal fungi (AMF ...

    African Journals Online (AJOL)

    Arbuscular-mycorhizal fungi (AMF) from melon plants grown in Van province, were studied by nested-PCR method to establish colonization ratio of related fungi in plants and to detect the fungi at species level. From 10 different locations, a total of 100 soil samples were taken from rhizosphere area of melon plants.

  6. INTERACCIÓN PLANTA-HONGOS MICORRÍZICOS ARBUSCULARES

    Directory of Open Access Journals (Sweden)

    Gabriel Camarena-Gutiérrez

    2012-01-01

    Full Text Available La simbiosis de la micorriza arbuscular está formada por las raíces de más del 80 % de las especies de plantas terrestres y los hongos Zigomicetes del Orden Glomales. Los efectos benéficos de esta simbiosis suceden como resultado de un diálogo molecular complejo entre los socios simbióticos. La identificación de las moléculas involucradas en este proceso es un prerrequisito para una mayor com¬prensión de la simbiosis. Hay evidencia de los eventos de señalización-reconocimiento en diferentes estados de las interacciones planta-hongo en la micorriza arbuscular, pero no se conoce la naturaleza de las moléculas señal y los procesos de percepción-transducción. Para conocer el potencial de la micorriza arbuscular en la agricultura sustentable, es preciso identificar las moléculas principales de la interacción planta-hongo. Existen numerosos métodos disponibles para el análisis molecular de los hongos arbusculares que ayudan a comprender la interacción dinámica entre las plantas y éstos.

  7. Shoot- and root-borne cytokinin influences arbuscular mycorrhizal symbiosis

    NARCIS (Netherlands)

    Rebeca Cosme, M.P.

    2016-01-01

    The arbuscular mycorrhizal (AM) symbiosis is functionally important for the nutrition and growth of most terrestrial plants. Nearly all phytohormones are employed by plants to regulate the symbiosis with AM fungi, but the regulatory role of cytokinin (CK) is not well understood. Here, we used

  8. Fiber, food, fuel, and fungal symbionts.

    Science.gov (United States)

    Ruehle, J L; Marx, D H

    1979-10-26

    Virtually all plants of economic importance form mycorrhizae. These absorbing organs of higher plants result from a symbiotic union of beneficial soil fungi and feeder roots. In forestry, the manipulation of fungal symbionts ecologically adapted to the planting site can increase survival and growth of forest trees, particularly on adverse sites. Vesicular-arbuscular mycorrhizae, which occur not only on many trees but also on most cultivated crops, are undoubtedly more important to world food crops. Imperatives for mycorrhizal research in forestry and agriculture are (i) the development of mass inoculum of mycorrhizal fungi, (ii) the interdisciplinary coordination with soil management, plant breeding, cultivation practices, and pest control to ensure maximum survival and development of fungal symbionts in the soil, and (iii) the institution of nursery and field tests to determine the circumstances in which mycorrhizae benefit plant growth in forestry and agri-ecosystems.

  9. Inoculum of arbuscular mycorrhizal fungi for production systems: science meets business

    Czech Academy of Sciences Publication Activity Database

    Gianinazzi, S.; Vosátka, Miroslav

    2004-01-01

    Roč. 82, - (2004), s. 1264-1271 ISSN 0008-4026 Institutional research plan: CEZ:AV0Z6005908 Keywords : Inoculum production * mycorrhiza applications Subject RIV: EF - Botanics Impact factor: 1.194, year: 2004

  10. Tripartite symbiosis of Sophora tomentosa, rhizobia and arbuscular mycorhizal fungi.

    Science.gov (United States)

    Toma, Maíra Akemi; Soares de Carvalho, Teotonio; Azarias Guimarães, Amanda; Martins da Costa, Elaine; Savana da Silva, Jacqueline; de Souza Moreira, Fatima Maria

    Sophora tomentosa is a pantropical legume species with potential for recovery of areas degraded by salinization, and for stabilization of sand dunes. However, few studies on this species have been carried out, and none regarding its symbiotic relationship with beneficial soil microorganisms. Therefore, this study aimed to evaluate the diversity of nitrogen-fixing bacteria isolated from nodules of Sophora tomentosa, and to analyze the occurrence of colonization of arbuscular mycorrhizal fungi on the roots of this legume in seafront soil. Thus, seeds, root nodules, and soil from the rhizosphere of Sophora tomentosa were collected. From the soil samples, trap cultures with this species were established to extract spores and to evaluate arbuscular mycorhizal fungi colonization in legume roots, as well as to capture rhizobia. Rhizobia strains were isolated from nodules collected in the field or from the trap cultures. Representative isolates of the groups obtained in the similarity dendrogram, based on phenotypic characteristics, had their 16S rRNA genes sequenced. The legume species showed nodules with indeterminate growth, and reddish color, distributed throughout the root. Fifty-one strains of these nodules were isolated, of which 21 were classified in the genus Bacillus, Brevibacillus, Paenibacillus, Rhizobium and especially Sinorhizobium. Strains closely related to Sinorhizobium adhaerens were the predominant bacteria in nodules. The other genera found, with the exception of Rhizobium, are probably endophytic bacteria in the nodules. Arbuscular mycorrhizal fungi was observed colonizing the roots, but arbuscular mycorhizal fungi spores were not found in the trap cultures. Therefore Sophora tomentosa is associated with both arbuscular mycorhizal fungi and nodulating nitrogen-fixing bacteria. Copyright © 2017 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  11. Infection of guinea pigs with vesicular stomatitis New Jersey virus Transmitted by Culicoides sonorensis (Diptera: Ceratopogonidae).

    Science.gov (United States)

    Pérez De León, Adalberto A; O'Toole, Donal; Tabachnick, Walter J

    2006-05-01

    Intrathoracically inoculated Culicoides sonorensis Wirth & Jones were capable of transmitting vesicular stomatitis New Jersey virus (family Rhabdoviridae, genus Vesiculovirus, VSNJV) during blood feeding on the abdomen of six guinea pigs. None of the guinea pigs infected in this manner developed clinical signs of vesicular stomatitis despite seroconversion for VSNJV. Guinea pigs infected by intradermal inoculations of VSNJV in the abdomen also failed to develop clinical signs of vesicular stomatitis. Three guinea pigs given intradermal inoculations of VSNJV in the foot pad developed lesions typical of vesicular stomatitis. Transmission by the bite of C. sonorensis may have facilitated guinea pig infection with VSNJV because a single infected C. sonorensis caused seroconversion and all guinea pigs infected by insect bite seroconverted compared with 50% of the guinea pigs infected by intradermal inoculation with a higher titer VSNJV inoculum. The role of C. sonorensis in the transmission of VSNJV is discussed.

  12. OCCURRENCE OF ARBUSCULAR MYCORRHIZAL FUNGI IN SOME MEDICINAL PLANTS OF KERALA

    Science.gov (United States)

    Mathew, Abraham; Malathy, M.R.

    2006-01-01

    The occurrence of mycorrhiza in 40 selected medicinal plants was studied. The percentage of mycorrhizal colonization in each of the plant was calculated. The colonization was found to be very less in four plants and very high in six plants. All others showed a moderate level of colonization. The present work suggests the use of mycorrhiza as a biofertilizer to enhance the growth and yield of medicinal plants. PMID:22557224

  13. Epizootic vesicular stomatitis in Colorado, 1982: epidemiologic and entomologic studies.

    Science.gov (United States)

    Walton, T E; Webb, P A; Kramer, W L; Smith, G C; Davis, T; Holbrook, F R; Moore, C G; Schiefer, T J; Jones, R H; Janney, G C

    1987-01-01

    An epizootic of vesicular stomatitis (VS) caused by the New Jersey serotype of VS virus affected livestock and humans in 14 western states in 1982-1983. Epidemiological observations were made on at least 10% of the cattle in 4 dairy herds that were located in the vicinity of Grand Junction, Colorado. High rates of neutralizing antibody to the New Jersey serotype were seen in all cattle regardless of whether livestock in the dairy had clinical VS or a decrease in mild production. Antibody titers remained high in these cattle for as long as 2 years after the epizootic. No virus isolations were made from 32 humans with clinical signs compatible with viral disease. Entomological information was obtained during the epizootic from 23 premises in northwestern Colorado. Insect collections yielded 4 isolates from Culicoides spp. midges, 2 from C. variipennis, and 1 each from C. stellifer and C. (Selfia) spp. This is the first report of VS virus isolations from field-collected Culicoides.

  14. Vesicular glutamate release from central axons contributes to myelin damage.

    Science.gov (United States)

    Doyle, Sean; Hansen, Daniel Bloch; Vella, Jasmine; Bond, Peter; Harper, Glenn; Zammit, Christian; Valentino, Mario; Fern, Robert

    2018-03-12

    The axon myelin sheath is prone to injury associated with N-methyl-D-aspartate (NMDA)-type glutamate receptor activation but the source of glutamate in this context is unknown. Myelin damage results in permanent action potential loss and severe functional deficit in the white matter of the CNS, for example in ischemic stroke. Here, we show that in rats and mice, ischemic conditions trigger activation of myelinic NMDA receptors incorporating GluN2C/D subunits following release of axonal vesicular glutamate into the peri-axonal space under the myelin sheath. Glial sources of glutamate such as reverse transport did not contribute significantly to this phenomenon. We demonstrate selective myelin uptake and retention of a GluN2C/D NMDA receptor negative allosteric modulator that shields myelin from ischemic injury. The findings potentially support a rational approach toward a low-impact prophylactic therapy to protect patients at risk of stroke and other forms of excitotoxic injury.

  15. Oncotargeting by Vesicular Stomatitis Virus (VSV: Advances in Cancer Therapy

    Directory of Open Access Journals (Sweden)

    Suman Bishnoi

    2018-02-01

    Full Text Available Modern oncotherapy approaches are based on inducing controlled apoptosis in tumor cells. Although a number of apoptosis-induction approaches are available, site-specific delivery of therapeutic agents still remain the biggest hurdle in achieving the desired cancer treatment benefit. Additionally, systemic treatment-induced toxicity remains a major limiting factor in chemotherapy. To specifically address drug-accessibility and chemotherapy side effects, oncolytic virotherapy (OV has emerged as a novel cancer treatment alternative. In OV, recombinant viruses with higher replication capacity and stronger lytic properties are being considered for tumor cell-targeting and subsequent cell lysing. Successful application of OVs lies in achieving strict tumor-specific tropism called oncotropism, which is contingent upon the biophysical interactions of tumor cell surface receptors with viral receptors and subsequent replication of oncolytic viruses in cancer cells. In this direction, few viral vector platforms have been developed and some of these have entered pre-clinical/clinical trials. Among these, the Vesicular stomatitis virus (VSV-based platform shows high promise, as it is not pathogenic to humans. Further, modern molecular biology techniques such as reverse genetics tools have favorably advanced this field by creating efficient recombinant VSVs for OV; some have entered into clinical trials. In this review, we discuss the current status of VSV based oncotherapy, challenges, and future perspectives regarding its therapeutic applications in the cancer treatment.

  16. Oncotargeting by Vesicular Stomatitis Virus (VSV): Advances in Cancer Therapy.

    Science.gov (United States)

    Bishnoi, Suman; Tiwari, Ritudhwaj; Gupta, Sharad; Byrareddy, Siddappa N; Nayak, Debasis

    2018-02-23

    Modern oncotherapy approaches are based on inducing controlled apoptosis in tumor cells. Although a number of apoptosis-induction approaches are available, site-specific delivery of therapeutic agents still remain the biggest hurdle in achieving the desired cancer treatment benefit. Additionally, systemic treatment-induced toxicity remains a major limiting factor in chemotherapy. To specifically address drug-accessibility and chemotherapy side effects, oncolytic virotherapy (OV) has emerged as a novel cancer treatment alternative. In OV, recombinant viruses with higher replication capacity and stronger lytic properties are being considered for tumor cell-targeting and subsequent cell lysing. Successful application of OVs lies in achieving strict tumor-specific tropism called oncotropism, which is contingent upon the biophysical interactions of tumor cell surface receptors with viral receptors and subsequent replication of oncolytic viruses in cancer cells. In this direction, few viral vector platforms have been developed and some of these have entered pre-clinical/clinical trials. Among these, the Vesicular stomatitis virus (VSV)-based platform shows high promise, as it is not pathogenic to humans. Further, modern molecular biology techniques such as reverse genetics tools have favorably advanced this field by creating efficient recombinant VSVs for OV; some have entered into clinical trials. In this review, we discuss the current status of VSV based oncotherapy, challenges, and future perspectives regarding its therapeutic applications in the cancer treatment.

  17. Transferosomes - A vesicular transdermal delivery system for enhanced drug permeation

    Directory of Open Access Journals (Sweden)

    Reshmy Rajan

    2011-01-01

    Full Text Available Transdermal administration of drugs is generally limited by the barrier function of the skin. Vesicular systems are one of the most controversial methods for transdermal delivery of active substances. The interest in designing transdermal delivery systems was relaunched after the discovery of elastic vesicles like transferosomes, ethosomes, cubosomes, phytosomes, etc. This paper presents the composition, mechanisms of penetration, manufacturing and characterization methods of transferosomes as transdermal delivery systems of active substances. For a drug to be absorbed and distributed into organs and tissues and eliminated from the body, it must pass through one or more biological membranes/barriers at various locations. Such a movement of drug across the membrane is called as drug transport. For the drugs to be delivered to the body, they should cross the membranous barrier. The concept of these delivery systems was designed in an attempt to concentrate the drug in the tissues of interest, while reducing the amount of drug in the remaining tissues. Hence, surrounding tissues are not affected by the drug. In addition, loss of drug does not happen due to localization of drug, leading to get maximum efficacy of the medication. Therefore, the phospholipid based carrier systems are of considerable interest in this era.

  18. Expression of Vesicular Nucleotide Transporter in Rat Odontoblasts

    International Nuclear Information System (INIS)

    Ikeda, Erina; Goto, Tetsuya; Gunjigake, Kaori; Kuroishi, Kayoko; Ueda, Masae; Kataoka, Shinji; Toyono, Takashi; Nakatomi, Mitsushiro; Seta, Yuji; Kitamura, Chiaki; Nishihara, Tatsuji; Kawamoto, Tatsuo

    2016-01-01

    Several theories have been proposed regarding pain transmission mechanisms in tooth. However, the exact signaling mechanism from odontoblasts to pulp nerves remains to be clarified. Recently, ATP-associated pain transmission has been reported, but it is unclear whether ATP is involved in tooth pain transmission. In the present study, we focused on the vesicular nucleotide transporter (VNUT), a transporter of ATP into vesicles, and examined whether VNUT was involved in ATP release from odontoblasts. We examined the expression of VNUT in rat pulp by RT-PCR and immunostaining. ATP release from cultured odontoblast-like cells with heat stimulation was evaluated using ATP luciferase methods. VNUT was expressed in pulp tissue, and the distribution of VNUT-immunopositive vesicles was confirmed in odontoblasts. In odontoblasts, some VNUT-immunopositive vesicles were colocalized with membrane fusion proteins. Additionally P2X 3 , an ATP receptor, immunopositive axons were distributed between odontoblasts. The ATP release by thermal stimulation from odontoblast-like cells was inhibited by the addition of siRNA for VNUT. These findings suggest that cytosolic ATP is transported by VNUT and that the ATP in the vesicles is then released from odontoblasts to ATP receptors on axons. ATP vesicle transport in odontoblasts seems to be a key mechanism for signal transduction from odontoblasts to axons in the pulp

  19. Dynamic of arbuscular mycorrhizal population on Amazon forest from the south Colombia

    International Nuclear Information System (INIS)

    Pena Vanegas, Clara P

    2001-01-01

    This work compared changes occurred on the number of arbuscular mycorrhizal spores at three mature forests and three regenerative forests, before and after clear-cutting. Results suggest that it is possible to predict the quantity of arbuscular mycorrhizal inocule after clear-cutting if initial number and type of forests is known before. A model to explain these changes shows that arbuscular mycorrhizal depletion on mature forests is about 70% after clear-cutting. Survival mycorrhizal populations colonize regenerative forests. Then, if a clear-cutting occurs on regenerative forests, arbuscular mycorrhizal populations will decrease on 35%, being less drastic that it occurred on mature forests

  20. First case report of vesicular stomatitis in the State of Paraíba, Brazil

    Directory of Open Access Journals (Sweden)

    Inácio José Clementino

    2014-10-01

    Full Text Available The present report describes the first case of vesicular stomatitis in the State of Paraíba, Brazil. Records from the Official Veterinary Services of the State of Paraíba were analyzed while responding to a suspected case of vesicular disease at a property (property I in the municipality of Pombal in which the cattle showed clinical signs and lesions of vesicular disease. Surveillance in the surrounding area revealed similar lesions in cattle at two other properties (II and III. Based on these events, the suspicion was considered well founded, and samples were collected for evaluation at the National Agricultural Laboratory of the State of Pará. The property was interdicted, and those located within a 3 km radius (perifocal from the focus were inspected. At property I, 42.86% (6/14 of the cattle showed vesicular disease lesions characterized by intense sialorrhea, ruptured oral vesicles, epithelial detachment of the tongue and muzzle, and vesicular lesions in the udder and interdigital space. Similar lesions were detected in cattle at properties II and III, affecting 80.95% (34/42 and 11.54% (3/26 of the animals, respectively. Tissue samples collected from the three properties were positive for the vesicular stomatitis virus (Indiana 3 subtype. The properties were monitored for 21 days after the last infected animal was cured, and afterwards, the three properties were released.

  1. Availability of caesium radionuclides to plants - classification of soils and role of mycorrhiza

    Energy Technology Data Exchange (ETDEWEB)

    Drissner, J.; Buermann, W.; Enslin, F.; Heider, R.; Klemt, E.; Miller, R.; Schick, G.; Zibold, G. [Fachhochschule Ravensburg-Weingarten, D-88241 Weingarten (Germany)

    1998-10-01

    At different locations in spruce stands spread rather homogeneously over southern Baden-Wuerttemberg, samples of soil and plants were taken and the vertical distribution of the caesium radionuclides in the soil was studied. As a direct measure of the bioavailability, the aggregated transfer factor, T{sub ag}, was determined for fern, bilberry, raspberry, blackberry, and clover. The T{sub ag} (in m2 kg{sup -1}) is defined by the specific caesium activity (in Bq kg{sup -1}) of the dry mass of the plants, divided by the total inventory (in Bq m{sup -2}) of the soil. It varies between 0{center_dot}5 and 0{center_dot}001 m2kg{sup -1}, being highest for fern and lowest for blackberry or clover at all sampling sites. Most decisive for the value of the T{sub ag} are kind of humus deposit, thickness and pH value of the humus layers. Also important are the soil properties, whereas geology has only a minor influence on T{sub ag}. At different sampling sites in spruce forests, the T{sub ag} can vary by two orders of magnitude for one plant species. Caesium desorption experiments were performed. We could not find a dependence of the transfer of caesium to the plant on the desorbability of caesium from the soil, which implies a more complex transport mechanism than simple ion exchange in the soil solution. It is suggested that the transport of caesium is mediated by mycorrhiza fungi. Therefore, we studied the density of mycorrhiza hyphae in the O{sub f}, O{sub h} and A{sub h} soil horizons of two sites differing in T{sub ag} by a factor of 10. The densities of mycorrhiza hyphae in the O{sub h} and A{sub h} soil horizons each differ by a factor of 2 for the two sites. Yet, the effect of the hyphae density on radiocaesium uptake has to be a subject of further investigation. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  2. Optical properties of arbuscular mycorrhizal fungal structures

    International Nuclear Information System (INIS)

    Perez, Adverdi; V-Hernandez, Alejandra; Rudamas, Carlos; Dreyer, Beatriz

    2008-01-01

    It was already reported by B. Dreyer at al. [1] that all fungal structures, both intra- and extra-radical fluoresced under blue light excitation regardless of their state (dead or alive). The source of the so called autofluorescence appears to be localized in the fungal cell wall. This supports the use of photoluminescence for the evaluation of AM colonization. However, the interpretation of these results is still in discussion [1-4]. In this work, arbuscular mycorrhizal spores were isolated from the rhizosphere of mango (Mangifera indica L.) plants by the method of wet sieving and decanting of Gerdemann and Nicolson [5] and studied by photoluminescence spectroscopy. Our experimental setup consists of an epifluorescence microscope (EM) coupled to a CCD-spectrometer through an arrangement of a home-made-telescope + fiber optic. This experimental setup allows the capture of images of the mycorrhizal structures (as usual in a standard epifluorescence microscope) combined with measurements of their corresponding emission bands. The preliminary results based on images obtained by standard EM do not clearly show that the emission is originated in the fungal cell walls as reported in Ref. 1. On the other hand, a very broad emission band in the visible part of the electromagnetic spectrum was observed in these spores by exciting at 450-490 nm and 300- 380 nm. We obtain a Full Width at Half Maximum (FWHM) of around 200 nm for this emission band whichis centered at 515 nm. This broad band seems to be composed of two narrower bands peaked around 494 and 547 nm and with FWHM of 50 nm and 150 nm, respectively. The profile of the observed emission band is in good agreement with the bands reported in Ref. 1 for vesicles, arbuscules and spores measured using the λ-Scan of a confocal laser scanning microscope. However, our results for spores show that the maxima of the narrower bands are shifted to higher energies in comparison to the corresponding bands observed in Ref. 1

  3. 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.

  4. 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.

  5. Effects of salt stress and mycorrhiza fungi on morpho-physiological characteristics of sweet corn

    Directory of Open Access Journals (Sweden)

    seyed Abdolreza kazemeini

    2017-06-01

    Full Text Available In order to investigate the interaction of mycorrhizal fungi and salinity on growth and physiological characteristics of sweet corn, a greenhouse experiment was conducted at College of Agriculture, Shiraz University, in 2014. The experimental design was factorial based on Completely Randomized Design in three replications. Treatments included salinity at four levels (0.4 (control, 4, 7, 10 dS m-1, and the fungi at three levels (no fungi (control, Glomus mosseae, Glomus intraradices. Results indicated that at flowering stage, with increasing salinity levels, leaf chlorophyll a, b and a+b content and carotenoid decreased at a rate of 18.9, 52.4, 33.1, and 34.5 respectively. Application of mycorrhiza under salinity, partially offset the negative impacts and increased tolerance of maize to NaCl by enhancing SOD and CAT activities, chlorophyll contents, carotenoid and K concentrations in leaves, plant height, leaf area, and total dry weight at flowering stage significantly, compared to control. The Na/K ratio at salinity level of 10 dS m-1 in treatments inoculated with GIN and GM fungi decreased by 39.69 and 40.45 percentage, respectively. Increases plant height, leaf area, total dry weight, concentrations of chlorophyll a, b, chlorophyll a+b and carotenoid and K, the activity of antioxidant enzymes compared with the control. Moreover, GIN type fungi had a greater advantage over GM and reduced the negative effects of salinity. Results indicated that application of mycorrhiza alleviated the adverse effect of salinity stress and improve the sweet corn dry weight up to 38 percentage at salinity level of 10 dS m-1.

  6. 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

  7. Survey the Effect of Mycorrhiza and Azospirillum of Wheat Cultivars Resistance in Yellow Rust

    Directory of Open Access Journals (Sweden)

    M. Jiriaie

    2017-01-01

    Full Text Available Introduction: Wheat is one of the major agricultural crops with respect to human nutrition. It is cultivated over a wide range of environments, because of wide adaptation to diverse environmental conditions. In Iran, 6.2 million hectares are under wheat cultivation, of which 33% is irrigated and 67% is rain-fed, the irrigated wheat growing areas (2 million hectares are located mostly in southern, central and east of Iran Production of crops is under the influence of plant genetic structure, environmental conditions and their interactions. Biotic and abiotic stresses are considered to lower production. Among the biotic stress, the fungal disease is the main factor limiting production of crop plants in hot and humid regions. Stripe rust was not a serious economic concern to the wheat industry for most of the 1990’s due to the use of resistant varieties. However, by 2003 it had developed into a significant issue, particularly as new path types evolved. Even in the dry years of 2003 and 2004, stripe rust cost growers significant income. Provide country's need for wheat as a strategic product, meanwhile, production is free from chemical fungicide is a high but achievable goal. So in order to achieve fertilizer and fungicide resources that in addition to having no adverse effects on consumers and the environment, has been economically able to provide nutrition need of crop plant, is very important. Materials and Methods: With this approach, to survey the effect of Mycorrhiza and Azospirillum in resistance to yellow rust in wheat cultivars, an experiment was conducted at the research station of the Shahid Chamran University of Ahvaz, Iran in 2012-13. The experimental design was factorial based on a randomized complete block design with three replications. The treatments include of Mycorrhiza fungi in three levels (without application of Mycorrhiza strain and using strain Glomus intraradices and Glomus mosseae, Azospirillum lipoferum bacterium in two

  8. Effects of whey on the colonization and sporulation of arbuscular ...

    African Journals Online (AJOL)

    The aim of this study is to research the effect of 2 different doses of whey [50 ml kg-1(W50) and 100 ml kg-1(W100)], an important organic waste, on colonization and sporulation of arbuscular mycorhizal fungus (AMF) Glomus intraradices'(G.i.) inoculated to lentil plant and the effects of changing P ratio in the soil and plant as ...

  9. Arbuscular Mycorrhizal Symbiosis Alleviates Diesel Toxicity on Melilotus albus

    International Nuclear Information System (INIS)

    Hernandez-Ortega, H. A.; Alarcon, A.; Ferrera-Cerrato, R.; Zavaleta-Mancera, H. A.

    2009-01-01

    Petroleum hydrocarbons (PH) affect plant growth and development by limiting water absorption and nutrient availability. Arbuscular mycorrhizal fungi (AMF) have been demonstrated to increase plant tolerance of grass species to PH, but the performance of AMF on legume species during phytorremediation of PH-contaminated soils has been scarcely understood. Thus, this research evaluated the effects of AMF on tolerance and growth of Melilotus albus in a diesel-contaminated soil. (Author)

  10. Arbuscular Mycorrhizal Symbiosis Alleviates Diesel Toxicity on Melilotus albus

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez-Ortega, H. A.; Alarcon, A.; Ferrera-Cerrato, R.; Zavaleta-Mancera, H. A.

    2009-07-01

    Petroleum hydrocarbons (PH) affect plant growth and development by limiting water absorption and nutrient availability. Arbuscular mycorrhizal fungi (AMF) have been demonstrated to increase plant tolerance of grass species to PH, but the performance of AMF on legume species during phytorremediation of PH-contaminated soils has been scarcely understood. Thus, this research evaluated the effects of AMF on tolerance and growth of Melilotus albus in a diesel-contaminated soil. (Author)

  11. Arbuscular Mycorrhizal Fungal 14-3-3 Proteins Are Involved in Arbuscule Formation and Responses to Abiotic Stresses During AM Symbiosis.

    Science.gov (United States)

    Sun, Zhongfeng; Song, Jiabin; Xin, Xi'an; Xie, Xianan; Zhao, Bin

    2018-01-01

    Arbuscular mycorrhizal (AM) fungi are soil-borne fungi belonging to the ancient phylum Glomeromycota and are important symbionts of the arbuscular mycorrhiza, enhancing plant nutrient acquisition and resistance to various abiotic stresses. In contrast to their significant physiological implications, the molecular basis involved is poorly understood, largely due to their obligate biotrophism and complicated genetics. Here, we identify and characterize three genes termed Fm201 , Ri14-3-3 and RiBMH2 that encode 14-3-3-like proteins in the AM fungi Funneliformis mosseae and Rhizophagus irregularis , respectively. The transcriptional levels of Fm201 , Ri14-3-3 and RiBMH2 are strongly induced in the pre-symbiotic and symbiotic phases, including germinating spores, intraradical hyphae- and arbuscules-enriched roots. To functionally characterize the Fm201 , Ri14-3-3 and RiBMH2 genes, we took advantage of a yeast heterologous system owing to the lack of AM fungal transformation systems. Our data suggest that all three genes can restore the lethal Saccharomyces cerevisiae bmh1 bmh2 double mutant on galactose-containing media. Importantly, yeast one-hybrid analysis suggests that the transcription factor RiMsn2 is able to recognize the STRE (CCCCT/AGGGG) element present in the promoter region of Fm201 gene. More importantly, Host-Induced Gene Silencing of both Ri14-3-3 and RiBMH2 in Rhizophagus irregularis impairs the arbuscule formation in AM symbiosis and inhibits the expression of symbiotic PT4 and MST2 genes from plant and fungal partners, respectively. We further subjected the AM fungus- Medicago truncatula association system to drought or salinity stress. Accordingly, the expression profiles in both mycorrhizal roots and extraradical hyphae reveal that these three 14-3-3-like genes are involved in response to drought or salinity stress. Collectively, our results provide new insights into molecular functions of the AM fungal 14-3-3 proteins in abiotic stress responses and

  12. 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...... to accommodate new mycobionts. Such modifications will have involved checkpoints for recognition/rejection and the formation/breakdown of pelotons. These physiological mechanisms are so far largely unknown. The trophic versatility of the mycobionts and the apparently easy shifts could be a main factor...

  13. Flavonoids released by carrot (Daucus carota) seedlings stimulate hyphal development of vesicular-arbuscular mycorrhizal fungi in the presence of optimal CO2 enrichment.

    Science.gov (United States)

    Poulin, M J; Bel-Rhlid, R; Piché, Y; Chênevert, R

    1993-10-01

    Carbon dioxide has been previously identified as a critical volatile factor that stimulates hyphal growth ofGigaspora margarita, a vesiculararbuscular mycorrhizal fungus, and we determined the optimal concentration at 2.0%. The beneficial effect of CO2 on fungal development is also visible in the presence of stimulatory (quercetin, myricetin) or inhibitory (naringenin) flavonoids. Sterile root exudates from carrot seedlings stimulate the hyphal development ofG. margarita in the presence of optimal CO2 enrichment. Three flavonols (quercetin, kaempferol, rutin or quercetin 3-rutinoside) and two flavones (apigenin, luteolin) were identified in carrot root exudates by means of HPLC retention time. Flavonols like quercetin and kaempferol are known to have stimulatory effects on hyphal growth ofG. margarita.

  14. 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.)

  15. Vesicular trafficking of immune mediators in human eosinophils revealed by immunoelectron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Melo, Rossana C.N., E-mail: rossana.melo@ufjf.edu.br [Laboratory of Cellular Biology, Department of Biology, ICB, Federal University of Juiz de Fora, UFJF, Rua José Lourenço Kelmer, Juiz de Fora, MG 36036-900 (Brazil); Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, CLS 943, Boston, MA 02215 (United States); Weller, Peter F. [Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, CLS 943, Boston, MA 02215 (United States)

    2016-10-01

    Electron microscopy (EM)-based techniques are mostly responsible for our current view of cell morphology at the subcellular level and continue to play an essential role in biological research. In cells from the immune system, such as eosinophils, EM has helped to understand how cells package and release mediators involved in immune responses. Ultrastructural investigations of human eosinophils enabled visualization of secretory processes in detail and identification of a robust, vesicular trafficking essential for the secretion of immune mediators via a non-classical secretory pathway associated with secretory (specific) granules. This vesicular system is mainly organized as large tubular-vesicular carriers (Eosinophil Sombrero Vesicles – EoSVs) actively formed in response to cell activation and provides a sophisticated structural mechanism for delivery of granule-stored mediators. In this review, we highlight the application of EM techniques to recognize pools of immune mediators at vesicular compartments and to understand the complex secretory pathway within human eosinophils involved in inflammatory and allergic responses. - Highlights: • Application of EM to understand the complex secretory pathway in human eosinophils. • EM techniques reveal an active vesicular system associated with secretory granules. • Tubular vesicles are involved in the transport of granule-derived immune mediators.

  16. Computed tomography of the vesicular glands: anatomical animal model (Oryctolagus cuniculus)

    International Nuclear Information System (INIS)

    Dimitrov, R.; Stamatova-Yovcheva, K.; Hamza, S.; Toneva, Y.

    2014-01-01

    Spiral CT is a non-invasive imaging method of choice for animal anatomical studies. The aim of the study was to establish the imaging anatomical features of the vesicular glands in the rabbit. Eight sexually mature healthy clinically male New Zealand rabbits of 18 months of age with body weight from 2.8 kg to 3.2 kg were used. The animals were anesthetized. As contrast medium Opti-ray350 was administrated. The computed tomography scan was complied with certain bone and soft tissue markers. For this purpose, a whole body multi-slice spiral computed tomography scanner was used. The both soft tissue glands were heterogeneous and relatively hyperdense structures, and defined in detail from the adjacent soft tissues. The urinary bladder neck was ventrally to the glands. Both vesicular glands were better differentiated each other when the rabbit is examined in abdominal recumbence. In dorsal recumbence the shape of the transversal image of the glandular finding was oval. In abdominal recumbence both the left and right soft tissue vesicular gland were defined. Transversal anatomical computed tomographic investigation of the rabbit vesicular gland is a detailed and definitive method, to study the normal morphology of these glands. Key words: Vesicular Gland. Helical Computed Tomography. Anatomy. Rabbit

  17. Vesicular trafficking of immune mediators in human eosinophils revealed by immunoelectron microscopy

    International Nuclear Information System (INIS)

    Melo, Rossana C.N.; Weller, Peter F.

    2016-01-01

    Electron microscopy (EM)-based techniques are mostly responsible for our current view of cell morphology at the subcellular level and continue to play an essential role in biological research. In cells from the immune system, such as eosinophils, EM has helped to understand how cells package and release mediators involved in immune responses. Ultrastructural investigations of human eosinophils enabled visualization of secretory processes in detail and identification of a robust, vesicular trafficking essential for the secretion of immune mediators via a non-classical secretory pathway associated with secretory (specific) granules. This vesicular system is mainly organized as large tubular-vesicular carriers (Eosinophil Sombrero Vesicles – EoSVs) actively formed in response to cell activation and provides a sophisticated structural mechanism for delivery of granule-stored mediators. In this review, we highlight the application of EM techniques to recognize pools of immune mediators at vesicular compartments and to understand the complex secretory pathway within human eosinophils involved in inflammatory and allergic responses. - Highlights: • Application of EM to understand the complex secretory pathway in human eosinophils. • EM techniques reveal an active vesicular system associated with secretory granules. • Tubular vesicles are involved in the transport of granule-derived immune mediators.

  18. 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

  19. [Mycotrophic capacity and efficiency of microbial consortia of arbuscular mycorrhizal fungi native of soils from Buenos Aires province under contrasting management].

    Science.gov (United States)

    Thougnon Islas, Andrea J; Eyherabide, Mercedes; Echeverría, Hernán E; Sainz Rozas, Hernán R; Covacevich, Fernanda

    2014-01-01

    We characterized the infective and sporulation capacities of microbial consortia of arbuscular mycorrhizal fungi (AMF) native of Buenos Aires province (Argentina) and determined if some soil characteristics and mycorrhizal parameters could allow to select potentially beneficial inocula. Soil samples were selected from seven locations in Buenos Aires province all under agricultural (A) and pristine (P) conditions. The AMF were multiplied and mycorrhizal root colonization of trap plants was observed at 10 weeks of growth. Spore number in field was low; however, after multiplication spore density accounted for 80-1175 spores per 100g of soil. The principal component analysis showed that the P and Fe soil contents are the main modulators of infectivity and sporulation capacity. The mycorrhizal potential was determined in three locations, being high in Pristine Lobería and Agricultural Trenque Lauquen and low in Junín. Agricultural Lobería (AL) and Pristine Lobería (PL) inocula were selected and their efficiency was evaluated under controlled conditions. Even though shoot dry matter increases after inoculation was not significant (p>0.05) mycorrhizal response was greater than 40% for tomato and 25% for corn, particularly after inoculation with inocula from the agricultural management. These results could be associated to the incipient development of mycorrhizae in both species. Additional research should be conducted to further develop our findings in order to determine the factors involved in the selection of efficient inocula. Copyright © 2014 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

  20. Fungos micorrízicos arbusculares na formação de mudas de cafeeiro, em substratos orgânicos comerciais Arbuscular mycorrhizal fungi on the development of coffee plantlets using different organic substrates

    Directory of Open Access Journals (Sweden)

    Fabrício Sales Massafera Tristão

    2006-01-01

    Full Text Available Realizou-se um experimento, em casa de vegetação, em arranjo fatorial 9 x 4, com o objetivo de avaliar o efeito de substratos orgânicos comerciais e inoculação de fungos micorrízicos arbusculares (FMAs no desenvolvimento de mudas de cafeeiro, cultivar 'Catuaí Amarelo', IAC 62. Utilizaram-se substratos à base de fibra de coco (Golden Mix 11, Golden Mix 47 e Golden Mix 80, casca de pinus (Rendmax, Vida Verde com adubação, Vida Verde sem adubação e Terra do Paraíso, solo puro e solo + esterco (70% e 30%,v/v, inoculando-se os FMAs Glomus intraradices, Glomus etunicatum e Gigaspora margarita. Manteve-se um tratamento sem inoculação. Aos 200 dias após transplante avaliaram-se: altura, diâmetro do caule, número de folhas, matéria seca da parte aérea, matéria fresca da raiz, teor de fósforo na parte aérea, colonização radicular, comprimento do micélio externo, atividade da fosfatase ácida e teores de pigmentos fotossintetizantes nas folhas do cafeeiro. Independentemente da micorrização, o melhor crescimento das mudas foi obtido no substrato Vida Verde sem adubação. Os melhores efeitos da micorrização foram constatados nas plantas colonizadas por G. margarita e crescidas nos substratos convencional (solo + esterco e Vida Verde com adubação, nas quais se verificaram mais eficácia na utilização de P, o que reverteu em maior crescimento e produção de biomassa, resultando em maior eficiência simbiótica. No substrato solo + esterco, a micorrização favoreceu a concentração de pigmentos fotossintetizantes e diminuiu a atividade da fosfatase ácida nas folhas do cafeeiro.A greenhouse experiment with an alleatory factorial 9 x 4 scheme was carried out to evaluate the effects of different substrates and species of arbuscular mycorrhizal fungi (AMF on the development of coffee plants, cultivar Catuaí Amarelo, IAC 62. Nine substrates were used: seven commercial organic substrates - four substrates containing composted