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

Abstract

Abstract In the previous work concerning the effect of potassium nutrition on glycolysis in sweet potato roots (1), monoiodoacetic acid (MIA) and sodium fluoride (NaF) inhibited more strongly respiration in younger roots and root tip parts, and yet a potassium deficiency enhanced its inhibition. The inhibition of MIA, which inhibits triose phosphate dehydrogenase (2), may indicate the importance of the EMP pathway and the Krebs cycle (3,4). The inhibition of NaF, which in higher concentrations inhibits enolase (2), may suggest the importance of the metabolism following phosphoglycerate → phosphoenolpyruvate or the Krebs cycle (3,4). It is of interest, therefore, to elucidate the role of the Krebs cycle in respiration in sweet potato roots, and what significance potassium nutrition has in the Krebs cycle operation. This paper deals with experiments bearing on respiration in roots of sweet potato plants grown at varying degrees of potassium application, especially in the presence of various inhibitors and /...