UJI POTENSI BAKTERI INDIGENUS TANAH GAMBUT DI CAGAR BIOSFER GIAM SIAK KECIL-BUKIT BATU SEBAGAI AGEN BIOFERTILIZER

Abstract

Giam Siak Kecil – Bukit Batu (GSK-BB) Biosphere Reserves is one of peat swamp forest located in Siak and Bengkalis, Riau Province which is habitat for many soil bacterias. Soil bacteria is known with its ability to release phosphorus (P) or provide nitrogen (N) for plant. The group functional of these bacteria can be used for biofertilizer agents. So far, the collection of peat soil bacteria isolated from GSK-BB Biosphere Reserves has not known their potential as biofertilizer agent. The bacteria potential assay was conducted by using a spot method using pikovskaya agar for phosphate solubilizing bacteria and yeast extract mannitol agar for nitrogen fixing bacteria. The number of isolates analyzed was 64 isolates. Based on the solubility index, isolate P410-51 showed the highest phosphatase activity with a value 8.6 and isolate HP4 10-2 showed the highest nitrogen fixing ability with the ratio clear zone diameter/colony diameter (Z/K) value was 4.11. Seventeen phosphate solubilizing bacteria and two nitrogen fixing bacteria were qualitatively potential in solubilizing organic phosphate and nitrogen fixation respectively. Those isolates can be employed as a component of biofertilizer.