Physiological and biochemical changes in young maize plants under iron deficiency: 2. Catalase, peroxidase, and nitrate reductase activities in leaves

Abstract

Young maize plants, grown hydroponically, were supplied with different amounts (7.5,0.75,0.15, 0.075, and 0 mg Fe/L) of iron (Fe). At 14, 21, and 28 days, in vitro activities of catalase, peroxidase and nitrate reductase in leaves were determined. Strong and complete Fe deficiency resulted in decreased enzyme activities. Under moderate Fe deficiency—often a restoration of the normal activity after an initial reduction—was observed. The rapidity and the degree of reaction to Fe deficiency depended on the enzyme. The ratio peroxydase/catalase activity can not be applied as a reliable tool for diagnosis of Fe deficiency.