The Potential of Exopolysaccharide Bacterial Isolate from the Rhizosphere of Potato as Nitrogen Fixation

This study aims to examine the potential of exopolysaccharide (EPS) bacteria isolated from potato rizosphere to nitrogen fixation. The soil samples were taken from three different altitudes of 1000 m, 1300 m and 1500 m above sea level in Malino Tinggi Moncong districts, Gowa regency, South Sulawesi. Soil samples were cultured on ATCC No.14 medium to 10-8 further EPS bacteria cultured on Mac Concay medium for grouping of gram-negative bacteria. There are 15 isolates capable of fixing the free nitrogen cultured on Burk medium categorized based on percentage of growth ability obtained by 4 isolates (26.67 %) have strong growth ability (+++), 6 (40 %) isolates have medium growth ability (++) and 5 isolates (33.33 %) had weak growth ability (+). Isolate producer of eksopolisakarida bacteria that has the ability to grow strong with the highest percentage of total nitrogen found in P3T63 isolates of 1.42 % followed by P3A49 of 1.15 % and P3A50 of 0.92 %.