1. Ahmad F, Ahmad I, Khan MS (2005) Indole acetic acid production by the indigenous isolates of Azotobacter and fluorescent Pseudomonas in the presence and absence of tryptophan. Turk J Biol 29:29–34
2. Bais HP, Weir TL, Perry LG, Gilroy S, Vivanco JM (2006) The role of root exudates in rhizosphere interactions with plants and other organisms. Annu Rev Plant Biol 57:234–266
3. Banerjee M, Yesmin L (2002) Sulfur-oxidizing plant growth promoting Rhizobacteria for enhanced canola performance. US Patent
4. Barea JM, Andrade G, Bianciotto V, Dowling D, Lokhrke S, Bonfante P, O’gara F, Azcon-Aguilar C (1998) Impact on arbuscular mycorrhiza formation of Pseudomonas strains used as inoculants for biocontrol of soil-borne fungal plant pathogens. Appl Environ Microbiol 64:2304–2307
5. Barea JM, Azcon R, Azcon-Aguilar C (2004) Mycorrhizal fungi and PGPR. In: Werner D, Hampp R, Varma A, Abbott L (eds) Plant surface microbiology. Springer, Berlin, pp 351–362