ISSN 2756-3413
African Journal of Virology Research ISSN 3421-7347 Vol. 1 (11), pp. 123-126, November, 2007. © International Scholars Journals
Full Length Research Paper
A study of the IAA synthesis capacity of Rhizobium isolates
*Sachdev Singh, Banerji Latif and Gopal Sivasankar
Department of Microbiology, Faculty of Science, Babasaheb Bhimrao Ambedkar Bihar University, Bihar, India.
*Corresponding author: E-mail: [email protected]
Accepted 09 May, 2007
Abstract
Rhizobium isolates from root (Sesbania procumbens) and stem nodules (S. rostrata and S. procumbens) of Sesbania species were shown to produce indole-3-acetic acid (IAA) in culture supplemented with L-tryptophan. Production of IAA was maximal after 72 h of incubation when the bacteria reached stationary phase of growth. The cultural requirements were optimized for maximum IAA production. The effect of carbon (1%) and nitrogen sources (0.1%) revealed that glucose and potassium nitrate were best promoters for IAA production over controls. The effect of different concentrations of EDTA revealed that 0.2 gml-1 EDTA increased IAA production. Among the three isolates, maximum amount of IAA was produced by the Rhizobium isolate from S. procumbens. The IAA from this isolate was extracted, purified and identified by thin layer chromatography.
Key words: Rhizobium species, Indole acetic acid, Sesbania species, Rhizobium-legume symbiosis.