Siderophore productions of isolates were determined by the Chrome Azurole S (CAS) method of Schwyn and Neilands (1987).The production of siderophore was indicated by a change in color of the medium from blue to orange. Phosphate solubilizing activity of isolates was evaluated on Sperber medium: 0.5 g L-1 yeast extract,0.1 g L-1 CaCl2, 0.25 g L-1 MgSO4-7H2O, 2.5 g L-1 Ca3(PO4)2,10 g L-1 glucose, 15 g L-1 agar.
The productions of indole acetic acid (IAA) by the isolates were determined following the method of Bric et al. (1991). A 48 hold test bacterial culture grown on NGA-plate was inoculated into nutrient broth supplied with 3 mM tryptophan and incubated at 28 C for 48 h. Bacterial cells were centrifuged at 3000 rpm for 30 min.
(2004). The test strains were streaked onto the center of an NGApate and incubated overnight at 28 C.