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Abstract: Study of plant roots and the diversity of soil micro biota, such as bacteria, fungi and microfauna associated with them, is important for understanding the ecological complexities between diverse plants, microbes, soil and climates and their role in phytoremediation of contaminated soils. The arbuscular mycorrhizal fungi (AMF) are universal and ubiquitous rhizosphere microflora forming symbiosis with plant roots and acting as biofertilizers, bioprotactants, and biodegraders. In addition to AMF, soils also contain various antagonistic and beneficial bacteria such as root pathogens, plant growth promoting rhizobacteria including free-living and symbiotic N-fixers, and mycorrhiza helping bacteria. Their potential role in phytoremediation of heavy metal (HM) contaminated soils and water is becoming evident although there is need to completely understand the ecological complexities of the plant-microbe-soil interactions and their better exploitation as consortia in remediation strategies employed for contaminated soils. These multitrophic root microbial associations deserve multi-disciplinary investigations using molecular, biochemical, and physiological techniques. ecosystem restoration of heavy metal contaminated soils practices need to incorporate microbial biotechnology research and development. This review highlights the ecological complexity and diversity of plant-microbe-soil combinations, particularly AM and provides an overview on the recent developments in this area. It also discusses the role AMF play in phytorestoration of HM contaminated soils, i.e. mycorrhizoremediation.

[1] Albrecht, C., Geurts, R., Bisseling, T., 1999. Legume nodulation and mycorrhizae formation, two extremes in host specificity meet. The EMBO Journal, 18(2):281-288.

[2] Allen, M.F., 1991. The Ecology of Mycorrhiza. Cambridge Uni. Press, Cambridge, p.184.

[3] Allen, M.F., 1992. Mycorrhizal Functioning: An Integrative Plant-Fungal Process. Chapman & Hall Inc., Routledge, NY, p.534.

[4] Andrade, G., Mihara, K.L., Linderman, R.G., Bethlenfalvay, G.J., 1997. Bacteria from the rhizosphere and hyphorhizosphere soils of different arbuscular mycorrhizal fungi. Plant and Soil, 192(1):71-79.

[5] Asai, T., 1944. Die bedeutung der mikorrhiza fur das pflanzenleben. Japanese J. Bot., 12:359-408.

[6] Atkinson, D., Berta, G., Hooker, J.E., 1994. Impact of Mycorrhizal Colonization on Root Architecture, Root Longevity, and the Formation of Growth Regulators. In: Gininazzi, S., Scheupp, H. (Eds.), Impact of Arbuscular Mycorrhizas on Sustainable Agriculture and Natural Ecosystems. Birkhauser Verlag, Basal, p.89-99.

[7] Azcon-Aguilar, C., Barea, J.M., 1994. Interactions between Mycorrhizal Fungi and Other Rhizosphere Microorganisms. In: Allen, M.A. (Ed.), Mycorrhizal Functioning: An Integrative Plant-fungus Process. Chapman and Hall, London, p.163-198.

[8] Azcon-Aguilar, C., Jaizme-Vega, M.C., Calvet, C., 2002. The Contribution of Arbuscular Mycorrhizal Fungi to the Control of Soil-borne Plant Pathogens. In: Gianinazzi, S., Schuepp, H. (Eds.), Mycorrhizal Technology: from Genes to Bioproducts―Achievements and Hurdles in Arbuscular Mycorrhiza Research. Birkhauser, Basel, p.187-198.

[9] Bansal, M., Chamola, B.P., Sarwar, N., Mukerji, K.G., 2002. Mycorrhizosphere: Interactions between Rhizosphere Microflora. In: Mukerji, K.G., Chamola, B.P., Singh, J. (Eds.), Mycorrhizal Biology. Kluwer Academic/Planum Publishers, New York, p.143-152.

[10] Barea, J.M., 2000. Rhizosphere and Mycorrhizae of Field Crops. In: Toutant, P., Balazs, E., Galante, E., Lynch, J.M., Shepers, J.S., Werner, D., Werry, P.A. (Eds.), Biological Resource Management, Connecting Science and Policy (OECD). INRA and Springer, Berlin, Heidelberg, New York.

[11] Barea, J.M., Azon-Aguilar, C., Azcon, R., 1997. Interactions between Mycorrhizal Fungi and Rhizosphere Microorganisms within the Context of Sustainable Soil-plant System. In: Gange, A.C., Brown, V.K. (Eds.), Multrophic Interactions in Terrestrial Ecosystems. Blackwell, Oxford, p.65-77.

[12] Barea, J.M., Gryndler, M., Lemananceau, P., Schuepp, H., Azcon, R., 2002. The Rhizosphere of Mycorrhizal Plants. In: Gianinazzi, S., Schuepp, H., Barea, J.M., Haselwandter, K. (Eds.), Mycorrhizal Technology in Agriculture: from Genes to Bioproducts. Birkhauser, Basel.

[13] Barker, S.J., Duplessis, S., Tagu, D., 2002. The application of genetic approaches for investigations of mycorrhizal symbioses. Plant and Soil, 244(1/2):85-95.

[14] Behl, R.K., Sharma, H., Kumar, V., Narula, N., 2003. Interactions among mycorrhiza, Azobacter chroococcum and root characteristics of wheat varieties. J. Agron. & Crop Sci., 189(3):151-155.

[15] Bethlenfalvay, G.J., Linderman, R.G., 1992. Mycorrhizae in Sustainable Agriculture. The American Phytopathological Society, Special Publication No. 54, St Paul, Minnesota, USA, p.124.

[16] Bomberg, M., Jurgens, G., Saano, A., Sen, R., Timonen, S., 2003. Nested PCR detection of Archaea in defined compartments of pine mycorrhizospheres developed in boreal forest humus microcosms. FEMS Microbiol. Ecol., 43(2):163-171.

[17] Boruvka, L., Drabek, O., 2004. Heavy metal distribution between fractions of humic substances in heavy polluted soils. Plant Soil Environ., 50:339-345.

[18] Bottomley, P.G., 1992. Ecology of Bradyrhizobium and Rhizobium and Rhizobium. In: Stacey, G., Burris, R.H., Evans, H.J. (Eds.), Biological Nitrogen Fixation. Chapman and Hall, Lodon, p.293-348.

[19] Brundrett, M.C., 2002. Coevolution of roots and mycorrhizas of land plants. New Phytol., 154(2):275-304.

[20] Burrows, R.L., Pfleger, F.L., 2002. Arbuscular mycorrhizal fungi respond to increasing plant diversity. Can. J. Bot., 80(2):120-130.

[21] Chanway, C.P., Turkington, R., Holl, F.B., 1991. Ecological implications of specificity between plants and rhizosphere micro-organisms. Adv. Ecol. Res., 21:122-170.

[22] Chaudhry, T.M., Khan, A.G., 2002. Role of Symbiotic Organisms in Sustainable Plant Growth on Heavy Metal Contaminated Industrial Sites. In: Rajak, R.C. (Ed.), Biotechnology of Microbes and Sustainable Utilization. Scientific Publishers, Jodhpur, India, p.270-279.

[23] Chaudhry, T.M., Khan, A.G., 2003. Plants Growing on Abandoned Mine Site and Their Root Symbionts. In: Gorban, G.R., Lepp, N. (Eds.), Proceedings 7th International Conference on the Biogeochemistry of Trace Elements. Swedish University of Agricultural Sciences, Uppsala, Sweden, p.134-135.

[24] Chaudhry, T.M., Hayes, W.J., Khan, A.G., Khoo, C.S., 1998. Phytoremediation-focusing on accumulator plants that remediate metal-contaminated soil. Aust. J. Ecotox., 4:37-51.

[25] Chaudhry, M.S., Batool, Z., Khan, A.G., 2005. Preliminary assessment of plant community structure and arbuscular mycorrhizas in rangeland habitats of Cholistan Desert, Pakistan. Mycorrhiza, 15(8):606-611.

[26] Chin-A-Woeng, T.F.C., Bloemberg, G.V., Lugtenberg, B.J.J., 2003. Phenazines and their role in biocontrol by Pseudomonas bacteria. New Phytol., 157(3):503-523.

[27] Clark, R.B., Zeto, S.K., 2000. Mineral acquisition by arbuscular mycorrhizal plants. J. Plant Nutri., 23:867-902.

[28] Dodd, J.C., Boddington, C.L., Rodríguez, A., Gonzalez-Chavez, C., Mansur, I., 2000. Mycelium of arbuscular mycorrhizal fungi (AMF) from different genera: form, function and detection. Plant and Soil, 226(2):131-151.

[29] Doyle, R.J., Lee, N.C., 1986. Microbes, warfare, religion and human institutions. Can. J. Microbiol., 32:193-200.

[30] Driver, J.D., Holben, W.E., Rilling, M.C., 2005. Characterization of glomalin as a hyphal wall component of arbuscular mycorrhizal fungi. Soil Biol. Biochem., 37(1):101-106.

[31] Duc, G., Trouvelot, A., Gianinazzi-Pearson, V., Gianinazzi, S., 1989. First report of non-mycorrhizal mutant (myc^–) obtained in pea (Pisum sativum L.) and fababean (Vicia faba L.). Plant Sci., 60(2):215-222.

[32] Duponnois, R., Plenchette, C., 2003. A mycorrhiza helper bacterium enhances extomycorrhizal and endomycorrhizal symbiosis of Australian Acacia species. Mycorrhiza, 13:85-91.

[33] Edwards, S.G., Young, J.P.W., Fitter, A.H., 1998. Interactions between Pseudomonas fluorescens biocontrol agents and Glomus mosseae, an arbuscular mycorrhizal fungus, within the rhizosphere. FEMS Microbiology Letters, 166(2):297-303.

[34] Elasri, M., Delorme, S., Lemanceau, P., Stewart, G., Laue, B., Glickmann, E., Oger, P.M., Dessaux, Y., 2001. Acyle-homoserine lactone production is more common among plant-associated Pseudomonas spp. than among soilborne Pseudomonas spp. App. Environ. Microbiol., 67(3):1198-1209.

[35] Facelli, E., Facelli, J.M., Smith, S.E., Mclaughlin, M.J., 1999. Interactive effects of arbuscular mycorrhizal symbiosis, intraspecific competition and resource availability on Trifolium subterraneum cv. Mt. Barker. New Phytol., 141(3):535-547.

[36] Filion, M., St-Arnaud, M., Fortin, J.A., 1999. Interactive effects of arbuscular mycorrhizal fungus Glomus intraradices and different rhizosphere microorganisms. New Phytol., 141(3):525-533.

[37] Fitter, A.H., 1985. Functioning of vesicular-arbuscular mycorrhiza on growth and water relations of plants. New Phytol., 89:599-608.

[38] Fortin, J.A., Bécard, G., Declerck, S., Dalpé, Y., St-Arnaud, M., Coughlan, A.P., Piché, Y., 2002. Arbuscular mycorrhiza on root-organ cultures. Can. J. Bot., 80(1):1-20.

[39] Galleguillos, C., Aguirre, C., Barea, J.M., Azcon, R., 2000. Growth promoting effect of two Sinorhizobium meliloti strains (a wild type and its genetically modified derivative) on a non-legume plant species in specific interaction with two arbuscular mycorrhizal fungi. Plant Sci., 159(1):57-63.

[40] Gamalero, E., Trotta, A., Massa, N., Copetta, A., Martinotti, M.G., Breta, G., 2003. Impact of two fluorescent pseudomonads and an arbuscular mycorrhizal fungus on tomato plant growth, root architecture and P acquisition. Mycorrhiza, 14(3):185-192.

[41] Garbaye, J., 1994. Helper bacteria: a new dimension to the mycorrhizal symbiosis. New Phytol., 128(2):197-210.

[42] Garbaye, J., Churin, J.L., Duponnois, R., 1992. Effects of substrate disinfection, fungicide treatments and mycorrhization helper bacteria on ectomycorrhizal formation of pedunculate oak (Quercus robur) inoculated with Laccaria laccata in two bare-root nurseries. Biol. Fertil. Soils, 13(1):55-57.

[43] Giovannetti, M., Avio, L., 2002. Biotechnology of Arbuscular Mycorrhizae. In: Khachatourians, G.G., Arora, D.K. (Eds.), Applied Mycology and Biotechnology. Vol. 2: Agriculture and Food Production. Elsevier, Amsterdam, p.275-310.

[44] Glick, B.R., 1995. The enhancement of plant growth by free-living bacteria. Can. J. Microbiol., 41:109-117.

[45] Gonzalez-Chavez, C., D’Haen, J., Vangronsveld, J.J., Dodd, J.C., 2002. Copper sorption and accumulation by the extraradical mycelium of different Glomus spp. (arbuscular mycorrhizal fungi) isolated from the same polluted soil. Plant and Soil, 240(2):287-297.

[46] Gonzalez-Chavez, M.C., Carrillo-Gonzalez, R., Wright, S.F., Nichols, K., 2004. The role of glomalin, a protein produced by arbuscular mycorrhizal fungi, in sequestering potentially toxic elements. Environ. Pollution, 130(3):317-323.

[47] Harrison, M.J., 1997. The arbuscular mycorrhizal symbiosis: an underground association. Trends in Plant Sci., 2(2):54-60.

[48] Hayes, W.J., Chaudhry, T.M., Buckney, R.T., Khan, A.G., 2003. Phytoaccumulation of trace metals at the Sunny Corner mine, New South Wales, with suggestions for a possible remediation strategy. Aust. J. Toxicol., 9:69-82.

[49] He, Z.L., Yang, X.E., Stoffella, P.J., 2005. Trace elements in agroecosystems and impacts on the environment. J. Trace Elem. Med. Biol., 19(2-3):125-140.

[50] Jamal, A., Ayub, N., Usman, M., Khan, A.G., 2002. Arbuscular mycorrhizal fungi enhance zinc and nickel uptake from contaminated soil by soybean and lentil. Int. J. Phytoremed., 4(3):205-221.

[51] Janse, J.M., 1896. Les endophytes radicaux des quelques plantes Javanaises. Annals du Jardin Botanique Buitenzord, 14:53-212.

[52] Joner, E.J., Briones, R., Leyval, C., 2000. Metal-binding capacity of arbuscular-mycorrhizal mycelium. Plant and Soil, 226(2):227-234.

[53] Jones, F.R., 1924. A mycorrhizal fungus in the roots of legumes and some other plants. J. Agric. Res., 29:459-470.

[54] Kabata-Pendias, A., Pendias, H., 1992. Trace Elements in Soils and Plants, 2nd Ed. CRC Press, Boca Raton, FL.

[55] Kaldorf, M., Kuhn, A.J., Schroder, W.H., Hildebrandt, U., Bothe, H., 1999. Selective element deposits in maize colonized by a heavy metal tolerance conferring arbuscular mycorrhizal fungus. J. Plant Physiol., 154:195-206.

[56] Kapoor, A., Viraraghavan, T., 1995. Fungal biosorption―an alternative treatment option for heavy metal bearing wastewater: a review. Biores. Technol., 53(3):195-206.

[57] Kapulnik, Y., 1996. Plant Growth Promotion by Rhizosphere Bacteria. In: Waisel, Y., Eshel, A., Kafkafi, U. (Eds.), Plant Roots―The Hidden Half. Dekker, New York, p.769-781.

[58] Khan, A.G., 1971. Occurrence of Endogone spores in West Pakistan soils. Trans. Brit. Mycol. Soc., 56(2):217-224.

[59] Khan, A.G., 1974. The occurrence of mycorrhizae in halophytes, hydrophytes, and xerophytes, and of Endogone spores in adjacent soil. J. Gen. Microbiol., 81:7-14.

[60] Khan, A.G., 1975. Growth Effects of Vesicular-arbuscular Mycorrhiza on Crops in the Field. In: Sanders, F.E., Mosse, B., Tinker, P.B. (Eds.), Endomycorrhizas. Academic Press, New York, p.419-439.

[61] Khan, A.G., 2001. Relationships between chromium biomagnification ratio, accumulation factor, and mycorrhizae in plants growing on tannery effluent-polluted soil. Environ. Int., 26(5-6):417-423.

[62] Khan, A.G., 2002a. The Significance of Microbes. In: Wong, M.H., Bradshaw, A.D. (Eds.), The Restoration and Management of Derelict Land: Modern Approaches. World Scientific Publishing, Singapore, p.80-92.

[63] Khan, A.G., 2002b. The Handling of Microbes. In: Wong, M.H., Bradshaw, A.D. (Eds.), The Restoration and Management of Derelict Land: Modren Approaches. World Scientific Publishing, Singapore, p.149-160.

[64] Khan, A.G., 2003. Mycotrophy and Its Significance in Wetland Ecology and Wetland Management. In: Wong, M.H. (Ed.), Proceedings Croucher Foundation Study Institute: Wetland Ecosystems in Asia―Function and Management. Hong Kong, p.11-15.

[65] Khan, A.G., 2005. Role of soil microbes in the rhizospheres of plants growing on trace lement contaminated soils in phytoremediation. J. Trace Elem. Med. Biol., 18(4):355-364.

[66] Khan, A.G., Belik, M., 1995. Occurrence and Ecological Significance of Mycorrhizal Symbioses in Aquatic Plants. In: Verma, A., Hock, B. (Eds.), Mycorrhiza: Structure, Function, Molecular Biology and Biotechnology. Springer-Verlag, Heidelberg, p.627-666.

[67] Khan, A.G., Kuek, C., Chaudhry, T.M., Khoo, C.S., Hayes, W.J., 2000. Role of plants, mycorrhizae and phytochelators in heavy metal contaminated land remediation. Chemosphere, 41(1-2):197-207.

[68] Klyuchnikov, A.A., Kozherin, P.A., 1990. Dynamics of Pseudomonas fluorescens and Azospirillium brasilense populations during the formation of the vesicular arbuscular mycorrhiza. Microbiology, 59:449-452.

[69] Linderman, R.G., Paulitz, T.C., 1990. Mycorrhizal-rhizobacterial Interactions. In: Hornb, D. (Ed.), Biological Control of Soil-borne Plant Pathogens. CAB International, Wallingford, p.261-283.

[70] Lovato, P.E., Gianinazzi-Pearson, V., Trouvelot, A., Gianinazzi, S., 1996. The state of art mycorrhizas micropropagation. Adv. Agric. Sci., 10:46-52.

[71] Lugtenberg, B.J.J., Dekkers, L.C., 1999. What makes Pseudomonas bacteria rhizosphere competent. Environ. Microbiol., 1(1):9-13.

[72] Lynch, J.M., 1990. The Rhizosphere. John Wiley & Sons, West Sussex, UK.

[73] Marschner, P., Baumann, K., 2003. Changes in bacterial community structure induced by mycorrhizal colonization in split-root maize. Plant and Soil, 251(2):279-289.

[74] Mayo, K., Davis, R., Motta, J., 1986. Stimulation of germination of spores of Glomus versiforme by spore-associated bacteria. Mycologia, 78(3):426-431.

[75] Meyer, R.J., Linderman, R.G., 1986. Response of subterranean clover to dual inoculation with vesicular arbuscular mycorrhizal fungi and plant growth promoting rhizobacterium, Pseudomonas putida. Soil Biol. Biochem., 18(2):185-190.

[76] Minerdi, D., Bianciotto, V., Bonfante, P., 2002. Endosymbiotic bacteria in mycorrhizal fungi: from their morphology to genome sequences. Plant and Soil, 244(1/2):211-219.

[77] Mohammad, A., Khan, A.G., 2002. Monoxenic in vitro production and colonization potential of AM fungus Glomus intraradices. Indian J. Exp. Bot., 40:1087-1091.

[78] Mohammad, A., Khan, A.G., Kuek, C., 2000. Improved aeroponic culture of inocula of arbuscular mycorrhizal fungi. Mycorrhiza, 9(6):337-339.

[79] Mohammad, A., Mitra, B., Khan, A.G., 2004. Effects of sheared-root inoculum of Glomus intraradices on wheat grown at different phosphorus levels in the field. Agric. Ecosystems & Environment, 103(1):245-249.

[80] Morley, G.F., Gadd, G.M., 1995. Sorption of toxic metals by fungi and clay minerals. Mycol. Res., 99:1429-1438.

[81] Mosse, B., 1962. The establishment of vesicular-arbuscular mycorrhiza under aseptic conditions. J. Gen. Microbiol., 27:509-520.

[82] O’Connor, P.J., Smith, S.E., Smith, F., 2002. Arbuscular Mycorrhizas influence plant diversity and community structure in a semiarid herbland. New Phytol., 154(1):209-218.

[83] Paulitz, T.C., Linderman, R.G., 1989. Interactions between fluorescent pseudomonads and VA mycorrhizal fungi. New Phytol., 113(1):37-45.

[84] Peterson, R.L., Guinel, F.C., 2000. The Use of Pea Mutants to Study Regulation of Colonization by AM Fungi. In: Kapulnik, Y., Douds, D.D. (Eds.), Arbuscular Mycorrhiza: Physiology and Function. Kluwer Academic Publishers, Dordrecht, the Netherlands, p.147-171.

[85] Pfleger, F.L., Linderman, R.G., 1994. Mycorrhizae and Plant Health. Symposium Series, The American Phytopathological Society, St Paul, Minnesota, USA, p.344.

[86] Phipps, C.J., Taylor, T.N., 1996. Mixed arbuscular-mycorrhizae from the Triassic of Antarctica. Mycologia, 88:707-714.

[87] Pierson, L.S., Pierson, E.A., Morello, J.E., 2002. Positive and Negative Cross-communication among Rhizobacteria. In: Leong, S.A., Allen, C., Triplett, E.W. (Eds.), Biology of Plant-microbe Interactions. International Society for Molecular Plant-microbe Interactions, St Paul, MN, USA, p.256-262.

[88] Requena, N., Jimenez, I., Toto, M., Barea, J.M., 1997. Interactions between plant-growth-promoting rhizobacteria (PGPR), arbuscular mycorrhizal fungi and Rhizobium spp. in the rhizosphere of Anthyllis cytisoides, a model legume for revegetation in Mediterranean semi-arid ecosystem. New Phytol., 136(4):667-677.

[89] Resendes, C.M., Geil, R.D., Guinel, F.C., 2001. Mycorrhizal development in low nodulating pea mutant. New Phytol., 150(3):563-572.

[90] Rillig, M.C., Ramsey, P.W., Morris, S., Paul, E.A., 2003. Glomalin, an arbuscular-mycorrhizal fungal soil protein, respond to land-use change. Plant and Soil, 253(2):293-299.

[91] Rodríguez, H., Fraga, R., 1999. Phosphate solubilizing bacteria and their role in plant growth promotion. Biotech. Advances, 17(4-5):319-339.

[92] Schüßler, A., 2000. Glomus claroideum forms an arbuscular-mycorrhiza-like symbiosis with the hornwort Anthoceros punctatus. Mycorrhiza, 10(1):15-21.

[93] Sen, R., 2003. The root-microbe-soil interface: new tool for sustainable plant production. New Phytol., 157(3):391-398.

[94] Shuman, L.M., 1985. Fractionation method for soil microelements. Soil Science, 140(1):11-22.

[95] Simon, L.K., Bousquet, J., Levesque, R.C., Lalonde, M., 1993. Origin and diversification of endomycorrhizal fungi and coincidence with vascular land plants. Nature, 363(6424):67-69.

[96] Singh, S., Kapoor, K.K., 1998. Effects of inoculation of phosphate solubilizing microorganisms and an arbuscular mycorrhizal fungus on mongbean growth under natural soil condition. Mycorrhiza, 7(5):249-253.

[97] Smith, S.E., 2002. Soil microbes and plants―raising interest, mutual gains. New Phytol., 156(2):142-144.

[98] Smith, S.S., Read, D.J., 1997. Mycorrhizal Symbiosis, 2nd Ed. Academic Press, London.

[99] Sun, Y.P., Unestam, T., Lucase, S.D., Johanson, K.J., Kenne, L., Finlay, R., 1999. Exudation-reabsorption in a mycorrhizal fungus, the dynamic interface for interaction with soil and soil micro-organisms. Mycorrhiza, 9(3):137-144.

[100] Suresh, C.K., Bagyaraj, D.J., 2002. Mycorrhiza-microbe Interface: Effect on Rhizosphere. In: Sharma, A.K., Johri, B.N. (Eds.), Arbuscular Mycorrhizae. Scientific Publishers, Enfield, New Hampshire, USA, p.7-28.

[101] Sylvia, D.M., Jarstfer, A.G., 1994a. Sheared root inoculum of vesicular arbuscular mycorrhizal fungi. App. Environ. Microbiol., 58:229-232.

[102] Sylvia, D.M., Jarstfer, A.G., 1994b. Production of Inoculum and Inoculation with Arbuscular Mycorrhizal Fungi. In: Robson, A.D., Abbott, L.K., Malajczuk, N. (Eds.), Management of Mycorrhizas in Agricture, Horticulture and Forestry. Kluwer, Dordrecht, p.231-238.

[103] Taylor, T.N., Taylor, E.L., 1993. Biology and Evolution of Fossil Plants. Englewood Cliff, Prentice Hall, NJ, USA.

[104] Toro, M., Azcon, R., Barea, J.M., 1997. Improvement of arbuscular development by inoculation of soil with phosphate-solubilizing rhizobacteria to improve rock phosphate bioavailability (P³²) and nutrient cycling. App. Environ. Microbiol., 63:4408-4412.

[105] Turnau, K., 1998. Heavy metal content and localization in mycorrhizal Euphorbia cyparissias from zinc wastes in Southern Polland. Acta Societatis Botanicorum Poloniae, 67:105-113.

[106] Turnau, K., Haselwandter, K., 2002. Arbuscular Mycorrhizal Fungi: An Essential Component of Soil Microflora in Ecosystem Restoration. In: Gianinazzi, S., Schuepp, H. (Eds.), Mycorrhizal Technology: from Genes to Bioproducts. Birkhauser, Basel, p.137-149.

[107] van der Heijden, M.G.A., Klironomos, J.N., Ursic, M., Moutoglis, P., Streitwolf-Engel, R., Boller, T., Weimken, A., Sanders, J.R., 1998. Mycorrhizal fungal diversity determines plant biodiversity, ecosystem variability and productivity. Nature, 396(6706):69-72.

[108] van Elsas, J.D., Turner, S., Bailey, M.J., 2003. Horizontal gene transfer in the phytosphere. New Phytol., 157(3):525-537.

[109] Vivas, A., Marulanda, A., Ruiz-Lozana, J.M., Barea, J.M., Azcon, R., 2003. Influence of a Bacillus sp. on physiological activities of two arbuscular mycorrhizal fungi and on plant responses to PEG-induced drought stress. Mycorrhiza, 13(5):249-256.

[110] Vosátka, M., Gryndler, M., 1999. Treatment with culture fractions from Pseudomonas putida modifies the development of Glomus fistulosum mycorrhizae and response of potato and maize plants to inoculation. App. Soil Ecol., 11(2-3):245-251.

[111] Weller, D.M., 1988. Biological Control of Soil-born Plant Pathogens in the Rhizosphere with Bacteria. In: Waisel, Y., Eschel, A., Kafkafi, U. (Eds.), Plant Roots: The Hidden Half. Dekker, New York, p.769-781.

[112] Wright, S.F., Upadhyaya, A., 1998. A survey of soils for aggregate stability and glomalin, a glycoprotein produced by hyphae of arbuscular mycorrhizal fungi. Plant and Soil, 198(1):97-107.

[113] Xavier, I.J., Boyetchko, S.M., 2002. Arbuscular Mycorrhizal Fungi as Biostimulants and Bioprotectants of Crops. In: Khachatourians, G.G., Arora, D.K. (Eds.), App. Mycol. and Biotechnol. Vol. 2: Agriculture and Food Production. Elsevier, Amsterdam, p.311-330.

[114] Zhang, S., Reddy, M.S., Kloepper, J.W., 2002. Development of assay for assessing induced resistance by plant-growth-promoting-rhizobacteria against blue mold of tobacco. Biol. Control, 23(1):79-86.

[115] Zhou, J.L., 1999. Zn biosorption by Rhizopus arrhizus and other fungi. App. Microbiol. Biotechnol., 51(5):686-693.