Effect of a varied potassium nutrition on the uptake and incorporation of labelled nitrate by young tobacco plants (Nicotiana tabacum L.)

In young tobacco plants the N turnover was studied with labelled N in relation to the K nutritional status of the plants. Plants well supplied with K showed a higher percentage of labelled N in the nitrate fraction and in the protein fraction compared with the plants of lower K status. In the latter, however, the percentage of labelled N in the soluble amino‐acid fraction was higher. The experimental data support the assumption that K particularly favours the incorporation of amino acids into proteins.