Role of Cytokinins in Plant Growth Promotion by Rhizosphere Bacteria

  • Ines E. de Garcia Salamone
  • Russell K. Hynes
  • Louise M. Nelson


Plant growth regulators (PGRs) are organic substances that influence the physiology and development of plants at very low concentrations. Cytokinins are one of the five major groups of PGRs or phytohormones and regulate cytokinesis in plant cells. Soil microorganisms are capable of synthesizing PGRs such as cytokinins in pure culture, soil and in association with plant tissues. This chapter reviews the structure and function of cytokinins in plant tissues and their production by plant growth promoting rhizobacteria (PGPR). A role for microbially-produced cytokinins in plant growth and development is proposed. Cytokinin production by PGPR is an innovative alternative to enhance plant growth and may be a sustainable approach to improve the yield and quality of agricultural crops. However further research is necessary to understand the principles underlying cytokinin production by rhizobacteria and to develop cytokinin-producing inoculants for practical application by growers.

Key words

cytokinins phytohormones plant growth regulators PGPR rhizobacteria 


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Copyright information

© Springer 2005

Authors and Affiliations

  • Ines E. de Garcia Salamone
    • 1
  • Russell K. Hynes
    • 2
  • Louise M. Nelson
    • 3
  1. 1.Department of Applied Biology and Foods, Faculty of AgronomyUniversity of Buenos AiresArgentina
  2. 2.Agriculture Agri-Food CanadaSaskatoonCanada
  3. 3.Department of BiologyUniversity of British Columbia OkanaganKelownaCanada

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