• Amijee F, Tinker PB, Stribley DP. 1989. Effects of phosphorus on the morphology of VA mycorrhizal root system of leek (Allium porrum L.). Plant and Soil 119: 334336.
  • Atkinson D, Berta G, Hooker JE. 1994. Impact of mycorrhizal colonisation on root architecture, root longevity and the formation of growth regulators. In: GianinazziS, SchüeppH, eds. Impact of Arbuscular Mycorrhizas on Sustainable Agriculture and Natural Ecosystems. Basel : Birkhäuser Verlag, 8997.
  • Azcón R, Rubio R, Barea JM. 1991. Selective interactions between different species of mycorrhizal fungi and Rhizobium meliloti strains, and their effects on growth, N2 fixation (15N) and nutrition of Medicago sativa L. New Phytologist 117: 399404.
  • Azcón-Aguilar C, Barea JM. 1992. Interactions betwen mycorrhizal fungi and other rhizosphere micro-organisms. In: AllenMJ, ed. Mycorrhizal Functioning. An Integrative Plant-Fungal Process. Routledge : Chapman & Hall, New York, 163198.
  • Barea JM, Azcón-Aguilar C. 1982. Production of plant growth regulating substances by the vesicular-arbuscular mycorrhizal fungus Glomus mosseae. Applied Environmental Microbiology 43: 810813.
  • Barea JM, Azcón R, Azcón-Aguilar C. 1992. Vesicular-arbuscular mycorrhizal fungi in nitrogen-fixing systems. In: NorrisJR, ReadD, VarmaA, eds. Methods in Microbiology, vol 24. Techniques for the Study of Mycorrhizae. London : Academic Press, 391416.
  • Barea JM, Tobar R, Azcón R, Azcón-Aguilar C. 1993. Mycorrhizas in the IMPACT project: action/concept approaches and worktasks/methodologies. Final Sectorial Meeting on Biosafety and First Sectorial Meeting on Microbial Ecology. BIOTECH Programme, U.E. Abstract 4.4.12. Granada, Spain.
  • Berta G, Fusconi A, Trotta A. 1993. VA mycorrhizal infection and the morphology and function of root systems. Environmental Experimental Botany 33: 159173.
  • Berta G, Trotta A, Fusconi A, Hooker JE, Munro M, Atkinson D, Giovannetti M, Morini S, Fortuna P, Tisserant B, Gianinazzi-Pearson V, Gianinazzi S. 1995. Arbuscular mycorrhizal induced changes to plant growth and root system morphology in Prunus cerasifera. Tree Physiology 15: 281293.
  • Elliott LF, Lynch JM. 1995. The international workshop on establishment of microbial inocula in soils: cooperative research project on biological resource management of the organization for economic cooperation and development (OECD). American Journal of Alternative Agriculture 10: 5073.
  • Fitter AH. 1982. Morphometric analysis of root systems: application of the technique and influence of soil fertility on root system development in two herbaceous species. Plant, Cell and Environment 5: 313322.
  • Fitter AH, Stickland TR. 1991. Architectural analysis of plant root systems. II. Influence of nutrient supply on architecture in contrasting plant species. New Phytologist 118: 383389.
  • Hewitt EJ. 1952. Sand and water culture methods used in the study of plant nutrition. Technical Communication no. 22. Farnham Royal , Bucks , UK : Commonwealth Agricultural Bureau.
  • Hooker JE, Munro M, Atkinson D. 1992. Vesicular-arbuscular mycorrhizal fungi induced alteration in poplar root system morphology. Plant and Soil 145: 207214.
  • Jarrel WM, Beverley RB. 1981. The dilution effect in plant nutrition studies. In: BradyNC, ed. Advances in Agronomy, vol. 34. New York : Academic Press, 197224.
  • Lachica M, Aguilar A, Yañez J. 1973. Analisis foliar. Métodos utilizados en la Estación Experimental del Zaidín. Anales de Edafología y Agrobiología 32: 10331047.
  • O'Gara F, Dowling DN, Boesten B. 1994. Molecular ecology of rhizosphere micro-organisms. Germany : VCH Weinheim.
  • Phillips JM, Hayman DS. 1970. Improved procedures for clearing roots and staining parasitic and vesicular-arbuscular mycorrhizal fungi for rapid assessment of infection. Transactions of the British Mycological Society 55: 159161.
  • Sanjuán J, Olivares J. 1991. Multicopy plasmids carrying the Klebsiella pneumoniae nifA gene enhance Rhizobium meliloti nodulation competitiveness on alfalfa. Molecular Plant-Microbe Interactions 4: 365369.
  • Schellenbaum L, Berta G, Ravolanirina F, Tisserant B, Gianinazzi S, Fitter AH. 1991. Influence of endomycorrhizal infection on root morphology in a micropropagated woody plant species (Vitis vinifera L.). Annals of Botany 68: 135141.
  • Tobar RM, Azcón-Aguilar C, Sanjuán J, Barea JM. 1996. Impact of a genetically modified Rhizobium strain with improved nodulation competitiveness ability on the early stages of arbuscular mycorrhiza formation. Applied Soil Ecology (in press).
  • Walker C. 1992. Systematics and taxonomy of the arbuscular endomycorrhizal fungi (Glomales): a possible way forward. Agronomie 12: 887897.