UJI POTENSI KELARUTAN BATUAN FOSFAT OLEH BAKTERI PELARUT FOSFAT ASAL TANAH GAMBUT DI RIAU

Abstract

Phosphate (P) is a macro nutrient needed by plant. In peat soil, P element usually becomes inorganic phosphate in mineralization process by the help of phosphate solubilizing microbes (PSM). Inoculation of phosphate solubilizing bacteria (PSB) into soil could be served as alternative biofertilizer. The purpose of this study was to examine the potential of 198 PSB which were isolated from peat soil in Bukit Batu and Kampar Peninsula, Riau Province in solubilizing rock phosphate. The ability of bacteria in rock phosphate solubilizing was determined quantitatively. A number of 198 PSB isolates which were inoculated to modified liquid pikovskaya’s medium consists of rock phosphate were categorized high, medium and low. The result of median value test on modified liquid pikovskaya’s medium which consists of rock phosphate reveals that 56 (28,28%) PSB isolates were categorized high with P concentration ≥1,17 mg/l