Abstract
In vitro gluconic acid formation and phosphate solubilization from sparingly soluble phosphorus sources by two strains of the plant growth-promoting bacteria A. brasilense (Cd and 8-I) and one strain of A. lipoferum JA4 were studied. Strains of A. brasilense were capable of producing gluconic acid when grown in sparingly soluble calcium phosphate medium when their usual fructose carbon source is amended with glucose. At the same time, there is a reduction in pH of the medium and release of soluble phosphate. To a greater extent, gluconic acid production and pH reduction were observed for A. lipoferum JA4. For the three strains, clearing halos were detected on solid medium plates with calcium phosphate. This is the first report of in vitro gluconic acid production and direct phosphate solubilization by A. brasilense and the first report of P solubilization by A. lipoferum. This adds to the very broad spectrum of plant growth-promoting abilities of this genus.
References
Amooaghaie R, Mostajeran A, Emtiazi G (2002) The effect of compatible and incompatible Azospirillum brasilense strains on proton efflux of intact wheat roots. Plant Soil 243:155–160
Bashan Y (1990) Short exposure to Azospirillum brasilense Cd inoculation enhanced proton efflux in intact wheat roots. Can J Microbiol 36:419–425
Bashan Y, Holguin G, Lifshitz R (1993) Isolation and characterization of plant growth-promoting rhizobacteria. In: Glick BR, Thompson JE (eds) Methods in plant molecular biology and biotechnology. CRC, Boca Raton, Fla., pp 331–345
Bashan Y, Holguin G, de-Bashan LE (2004) Azospirillum-plant relationships: agricultural, physiological, molecular and environmental advances (1997–2003). Can J Microbiol 50, 521–577
Bergey’s Manual of Systematic Bacteriology (1989) Staley JT, Bryant MP, Pfennig N, Holt JG (eds). Lippincott Williams and Wilkins, Philadelphia, Pa.
Carrillo AE, Li CY, Bashan Y (2002) Increased acidification in the rhizosphere of cactus seedlings induced by Azospirillum brasilense. Naturwissenschaften 89:428–432
Chabot R, Antoun H, Cescas MP (1996) Growth promotion of maize and lettuce by phosphate-solubilizing Rhizobium legominosarum biovar. phaseoli. Plant Soil 184:311–321
Chang TT, Li CY (1998) Weathering of limestone, marble, and calcium phosphate by ectomycorrhizal fungal and associated microorganisms. Taiwan J For Sci 13:85–90
Chen PS Jr, Torribara TY, Warner H (1956) Microdetermination of phosphorous. Anal Chem 28:1756–1758
Deubel A, Gransee A, Merbach W (2000) Transformation of organic rhizodepositions by rhizosphere bacteria and its influence on the availability of tertiary calcium phosphate. J Plant Nutr Soil Sci 163:387–392
Goebel EM, Krieg NR (1984) Fructose catabolism in Azospirillum brasilense and Azospirillum lipoferum. J Bacteriol 159:86–92
Hartmann A, Zimmer W (1994) Physiology of Azospirillum. In: Okon Y (ed) Azospirillum/plant associations. CRC, Boca Raton, Fla., pp 15–39
Illmer P, Schinner F (1995) Solubilization of inorganic calcium phosphate-solubilization mechanisms. Soil Biol Biochem 27:257–263
Illmer P, Barbato A, Schinner F (1995) Solubilization of hardy-soluble AIPO4 with P-solubilizing microorganisms. Soil Biol Biochem 27:265–270
Janzen RA, McGill WB (1995) Community-level interactions control proliferation of Azospirillum brasilense Cd in microcosms. Soil Biol Biochem 27:189–196
Puente ME, Bashan Y, Li CY, Lebsky VK (2004) Microbial populations and activities in the rhizoplane of rock-weathering desert plants. I. Root colonization and weathering of igneous rocks. Plant Biol 6:629–642
Raven JA, Franco AA, Jesus EL de, Jacob-Neto J (1990) Proton extrusion and organic acid synthesis in nitrogen fixing symbioses involving vascular plants. New Phytol 114:369–390
Rodelas B, Salmeron V, Martinez-Toledo MV, Gonzalez-Lopez J (1994) Production of amino acids by Azospirillum brasilense in chemically-defined medium amended with malate, gluconate or fructose for use as a nitrogen-fixation bacterial fertilizer inoculum. Soil Biol Biochem 26:301–303
Rodriguez H, Fraga R (1999) Phosphate solubilizing bacteria and their role in plant growth promotion. Biotechnol Adv 17:319–339
Rodriguez H, Gonzalez T, Selman G (2000) Expression of a mineral phosphate solubilizing gene from Erwinia herbicola in two rhizobacterial strains. J Biotechnol 84:155–161
Seshadri S, Muthukumarasamy R, Lakshminarasimhan C, Ignacimuthu S (2000) Solubilization of inorganic phosphates by Azospirillum halopraeferans. Curr Sci 79:565–567
Shah S, Rao KK, Desai A (1993) Production of catecholate type of siderophores by Azospirillum lipoferum M. Indian J Exp Biol 31:41–44
Westby CA, Cutshall DS, Vigil GV (1983) Metabolism of various carbon sources by Azospirillum brasilense. J Bacteriol 156:1369–1372
Acknowledgements
Yoav Bashan participated in this study in memory of the late Messrs Avner and Uzi Bashan from Israel. We thank Delfa Redondo from ICIDCA for HPLC analysis, Juan-Pablo Hernandez of CIB for statistical analysis and drawing graphs, and Ira Fogel of CIB for editing the English text. This work was partially supported by Consejo Nacional de Ciencia y Tecnologia of Mexico (CONACYT Grant U39520-Z) and by the Bashan Foundation, USA.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Rodriguez, H., Gonzalez, T., Goire, I. et al. Gluconic acid production and phosphate solubilization by the plant growth-promoting bacterium Azospirillum spp.. Naturwissenschaften 91, 552–555 (2004). https://doi.org/10.1007/s00114-004-0566-0
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00114-004-0566-0