A collection of nine investigations for students enabling them to follow those transformations occurring in the soil which result in the recycling of nitrogen and the maintenance of fertility. Experiments include:. Nitrogen fixation by Azotobacter and Rhizobium. Hydrolysis of proteins - gelatine - casein - blood protein. Deamination of peptone. Oxidation of ammonia and nitrite. Denitrification of Nitrate. The kit contains:. Mannitol Salts Medium. Nutrient Gelatine. Peptone Water. Agricultural Dried Blood. Glucose Yeast Extract. Nutrient Casein Agar. Crystal Violet Solution. Nitrate Formation Medium. Nitrate Broth Medium. Ammonium Test Strips. Nitrate Test Strips. Full instructions. Additional materials required (not included):. Petri Dishes. Air dried soil. Pipettes. Sterile inoculating loop. Test Tubes (sterilised). Parafilm. Cotton Wool. Glass Microscope Slides.