Produksi IAA Dan Pelarutan Fosfat Secara In-Vitro Oleh Bakteri Penambat Nitrogen Yang Diisolasi Dari Tanah Sawah Cilacap

A total of twenty one nitrogen fixing bacteria (Azotobacter, Rhizobium , Azospirillum) were isolated from different location of Cilacap by dilution plate technique. These isolates were screened in vitro for their ability to dissolve and mineralization of inorganic phosphate Ca3(PO4)2 and organic phosphate respectively, and tested for the production of Indole Acetic Acid (IAA). All isolates were capable to solubilize Ca3 (PO4)2 in solid medium with various solubilization index ranged from 1.14-1.50 and 0.26 ug/ml to 4.79 ug/ml in liquid medium. All isolates also produces acid and alkaline phosphatase about 0.07-0.173 ug/ml p-nitrophenol/hour and 0.06-0.45 ug/ml p-nitrophenol/hour respectively. IAA production by 21 isolates nitrogen fixing bacteria after 3 days incubation in the range of 0.23-8.95 ug/ml. Prosiding Seminar Nasional Biodiversitas: Studi, Pemanfaatan dan Konservasi Keanekaragaman Hayati Nusantara dalam Bidang Kesehatan. Surakarta, 7 Februari 2014.