Effect of mineral nutrition on metabolic change induced in crop plant roots (III)

The previous work (1) with the bleeding sap from taro plants grown in soil culture showed that the diurnal periodicity in exudation process with the roots was not affected by the growth stage, nutirtion, temperature,, or light regime, although the amplitude and the period were altered by potassium deficiency. In the light of recent results in extensive studies on the exudation process in bleeding roots (2,3,4), one of the outstanding problems which remain to be clarified will be the effect of potassium deficiency on the periodicity in the exudation with plant roots. In this work, therefore, the effect of potassium deficiency on the diurnal periodicity in amino-N content of bleeding sap was examined with taro plants grown in solution culture at varying ammonium sulphate application.