Science & Mathematics » Biology » Nitrogen-fixing Rhizobium?

Nitrogen-fixing Rhizobium?

To isolate a nitrogen-fixing Rhizobium species a sample is taken from the rhizosphere of a leguminated alfalfa-plant. The sample is suspended in a liquid medium that contains all necessary macroelements and growth factors except nitrogen. The culture is placed in a shaking incubator to make sure that it received enough oxygen- however, no growth does take place, why?

2 Answers2