CULTURE MEDIA 23 



Medium 50 



Sodium Ammonium Phosphate Solution 

 Sodium ammonium phosphate (Na(NH4)HP04- 



4H2O) 3.4 gm. 



Potassium chloride (KCl) 2.0 gm. 



Magnesium sulphate (MgS04-7H20) 0.5 gm. 



Ferrous sulphate (FeS04-7H20) trace 



Magnesium carbonate (MgCOs) excess 



Distilled water 1,000.0 cc. 



To prevent a loss of ammonia do not add the MgCOs until 

 after sterilization 



Medium 51 



Sodium Nitrite Solution^ 



Sodium nitrite (NaN02) 1.0 gm. 



Sodium carbonate (Na2C03) 1.0 gm. 



Dipotassium phosphate (K2HPO4) 0.5 gm. 



Sodium chloride (NaCl) 0.5 gm. 



Magnesium sulphate (MgS04-7H20) 0.3 gm. 



Ferrous sulphate (FeS04-7H20) trace 



Distilled water 1,000 . cc. 



1 Fred, E. B., and A. Davenport, Soil Sci., 11: 389-404, 1921. 



Medium 52 

 Medium for Oxidation of Ammonia and Nitrite to Nitrate 



Ammonium sulphate ((NH4)2S04) 2.0 gm. 



Dipotassium phosphate (K2HPO4) 1.0 gm. 



Magnesium sulphate (MgS04-7H20) 0.5 gm. 



Sodium chloride (NaCl) 2.0 gm. 



Ferrous sulphate (FeS04-7H20) trace 



Calcium carbonate 5.0 gm. 



Tap water 1,000.0 cc. 



Add the calcium carbonate after sterilization. 



Medium 53 

 Washed Agar for Nitrifying Bacteria 



Agar (washed)2 25.0 gm. 



Water 1,000.0 cc. 



2 Allow the agar to wash in running water for 5 to 7 days, and dry at 60°C. 



