KAJIAN KANDUNGAN NITRAT (NO3-) TANAH DENGAN APLIKASI BEBERAPA BAKTERI PENAMBAT NITROGEN
Nitrate is one of the major nutrients for growth of plants and algae. Nitrate is very soluble in water and is very unstable so it becomes unavailable. The main source of nitrate comes from soil erosion, fertilizer, waste and nitrogen (N) accumulation. N uptake is done either by symbiotic or non-symbiotic bacteri. The Faculty of Agriculture of UBT has 14 rhizobacterial isolates capable of digesting N, but it is not yet known how much it can absorb N in the from of nitrates that such rhizobacteria can provide. This study aimed to determine the extent of the ability of 14 N-bonding bacterial isolates to provide nitrate (NO3-). This research used a complete randomized design that consisted of 16 treatmenst and 2 replicates. The treatments were K0 (soil without treatmen), K1 (Nutrient Broth) P1 (B1(17)) P2 (B1(19)), P3 (B3(10)), P4 (B4(15)), P5 (B3(12)), P6 (B3(16)), P7 (B3(19)) P8 (B3(9)), P9 (B4(12)), P10 (B4(5)), P11 (B5(13)), P12 (B5(15)), P13 (B5(19)) dan P14 (B5(9)). At P1 to P14 treatments the soil was irrigated whit nitogen-fixing bacterial isolates suspension at a densityof 108 cfu/mL. The treatment of K0 was soil without the addition of Nutrient Broth (NB) and bacterial whereas K1 was soil added with 100 mL organic Nutrient Broth (NB). The soil was then incubated for 21 dasy. The parameters of this study were soil pH analysis and soil nitrate (NO3-) analysis.The results showed that the bacterial isolate was able to provide N in the from of nitrates ranging from 35,06 ppm to 45,42 ppm and bacterial isolate B3(12), was able to provide N of 45,42 ppm. The results of soil pH parameters showed that the isolates with the highest pH score was isolate B3(10) , (P3) with pH acore of 4,69 the lowest pH was of 4,20 obtained from isolates B4(12), (P9).