Effect of photorespiratory inhibitors onin vivonitrate reduction in the leaves of barley and maize

摘要

The effects of photorespiratory inhibitors, alpha;-hydroxypyridinemethanesulphonate, isonicotinyl hydrazide, and amino-oxyacetate, onin vivonitrate reduction in the leaves of barley (C3) and maize (C4) were studied. The inhibitors had a pronounced effect on enzyme activity in the leaves of barley but not of maize. Photorespiratory substrates, glycolate and glycine, enhanced nitrate reduction in the leaves of barley. The enhancement was reversed by the inhibitors. It is proposed that glycine oxidation supports nitrate reduction in C3plants but not in C4plants.