POTENSI BAKTERI INDIGENOUS RHIZOSFER TANAMAN BAWANG MERAH DALAM MENGHASILKAN SULFAT PADA TANAH VERTISOL DI BREBES, INDONESIA

This study aims to obtain the best indigenous bacteria in increasing sulfate levels vertisol soil through oxidation process of sulfur sulfate. The was conducted polybags with media a screen house, Bulakelor Village, Keanggungan District, Brebes Regency. experiment arranged using completely randomized design (CRD) two factors. first factor is type bacteria: Control (B0); Bacillus sp (B1); Burkholderia cepacia (B2); Klebsiella aerogenes (B3) and variicola (B4) second incubation time: 3 (H3); 6 (H6); 9 (H9); 12 (H12) days. Each treatment repeated four times. Observation variables were (colorimetric method) increased (calculation method). Observational data analyzed F test if there significant difference, it continued Duncan's 95% confidence level (α = 5%). application sulfur-oxidizing can increase availability soil. administration an period days by 69.11% better than other treatments.