Biology and Fertility of Soils

, Volume 40, Issue 3, pp 188–193 | Cite as

Mitigation of salt stress in wheat seedlings by a gfp-tagged Azospirillum lipoferum

  • Macario Bacilio
  • Hilda Rodriguez
  • Manuel Moreno
  • Juan-Pablo Hernandez
  • Yoav Bashan
Original Paper


Root colonization and mitigation of NaCl stress on wheat seedlings were studied by inoculating seeds with Azospirillum lipoferum JA4∷ngfp15 tagged with the green fluorescent protein gene (gfp). Colonization of wheat roots under 80 and 160 mM NaCl stress was similar to root colonization with this bacterial species under non-saline conditions, that is, single cells and small aggregates were mainly located in the root hair zone. These salt concentrations had significant inhibitory effects on development of seedlings, but not on growth in culture of gfp-A. lipoferum JA4∷ngfp15. Reduced plant growth (height and dry weight of leaves and roots) under continuous irrigation with 160 mM NaCl was ameliorated by bacterial inoculation with gfp-A. lipoferum JA4∷ngfp15. Inoculation of plants subjected to continuous irrigation with 80 mM NaCl or to a single application of either NaCl concentration (80 or 160 mM NaCl) did not mitigate salt stress. This study indicates that, under high NaCl concentration, inoculation with modified A. lipoferum reduced the deleterious effects of NaCl; colonization patterns on roots were unaffected and the genetic marker did not induce undesirable effects on the interaction between the bacterium and the plants.


Azospirillum gfp Plant growth-promoting bacteria PGPR Salt stress mitigation 



We thank the following members of CIB (Mexico): Maria del Carmen Rodriguez for assisting in image analysis, Manuel Transviña for conductivity measurements, Baudilio Acosta for Na+ analysis, Ira Fogel for editing the English text, and Luz de-Bashan for technical aspects of the manuscript. Erick Cabrera (ATL Olympus, Mexico) enhanced the digital images. H.R. was a recipient of a “Catedra Patrimonial” fellowship from Consejo Nacional de Ciencia y Tecnologia of Mexico (CONACYT grant EX-000580). Wild-type strain Azospirillum lipoferum JA4 was donated by V.L.D. Baldani, CNPBS, Rio de Janeiro, Brazil. This work was partially supported by CONACYT (grant U39520-Z) of Mexico and the Bashan Foundation, USA. Yoav Bashan participated in this study in memory of the late Messrs Avner and Uzi Bashan from Israel.


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Copyright information

© Springer-Verlag 2004

Authors and Affiliations

  • Macario Bacilio
    • 1
  • Hilda Rodriguez
    • 1
    • 2
  • Manuel Moreno
    • 1
  • Juan-Pablo Hernandez
    • 1
  • Yoav Bashan
    • 1
  1. 1.Environmental Microbiology GroupCenter for Biological Research of the Northwest (CIB)La PazMexico
  2. 2.Cuban Research Institute on Sugarcane By-ProductsHavanaCuba

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