Laboratory and Green house Assays of Phospate Solubilizing Rhizobacteria to Improve Growth of Falcataria moluccana Seedling

Phosphate solubilizing bacteria (PSB) play an important role as plant growth promoting, through phosphate solubilization and IAA hormone production. This study was aimed at screening P solubilizing bacteria from post-tin mining soils, and examining their activity in promoting Falcataria moluccana seedling growth. The methods include inorganic phosphate and organic phosphates solubilization characterization in solid and liquid media, and inoculation of PSB isolates into seeds of F. moluccana in laboratory and greenhouse assays. A total 11 isolates exhibited P solubilization (organic and inorganic phosphates) activity and IAA production. Highest inorganic phosphate solubilization was exhibited by Bacillus sp. strain P6 (9.749 μg/mL at 72 h). In addition, Enterobacter cloacae strain P2 and Bacillus sp. strain P6 produced highest seed vigor index (SVI) and seed germination, respectively. Inoculation of E. cloacae strain P2 to the seedlings of F. moluccana also increased dry weight (42.63 mg), enchanced P content of the seedling (2.26 mg/g) and available P (52.65 mg/g) in rhizosphere soil.Keywords: Falcataria moluccana, IAA, P solubilization, rhizobacteria, rhizosphere International Journal of Agricultural Technology 2017 Vol. 13(5): 699-714 Available online http://www.ijat-aatsea.com ISSN 1686-9141