Occurrence of a stable nitrate reductase in Actinidia spp.

Abstract Following development of an in vitro assay, a NADH/NADPH bispecific nitrate reductase stable for at least a month at 4°C, and thermostable at temperatures to at least 60°C, has been identified in crude and partially‐purified extracts of leaves and roots of kiwifruit (Actinidia deliciosa). Stability characteristics were not confined to kiwifruit, but were found to extend to other members of the genus also.