Simple Spectroscopic Determination of Nitrate, Nitrite, and Ammonium in Arabidopsis thaliana.

Plants use nitrate, nitrite, and ammonium as inorganic nitrogen (N) sources. These N compounds are included in plant tissues at various concentrations depending on the balance between their uptake and assimilation. Thus, the contents of nitrate, nitrite, and ammonium are physiological indicators of plant N economy. Here, we describe a protocol for measurement of these inorganic N species in A. thaliana shoots or roots.