Biochemical changes in stored potato tubers with different rest periods

Abstract

Summary Ribonuclease, desoxyribonuclease, acid phosphatase, apyrase, α-amylase, peroxidase, and phenol oxidase activities were investigated in the eyes and parenchyma of stored potato tubers of cv. Baca and Bern with different rest periods as well as effect of storage temperature and isopropyl phenycarbamates on on enzyme activity. From deep rest until sprouting a distinct increase in enzyme activity was found, especially of hydrolases. In the eyes of the tubers with shorter rest period (cv. Bern), almost all investigated enzymes were more active, particulary in the rest period. Isopropyl phenylcarbamates inhibited the increase of most enzyme activity in the external parts of the tubers and in the ageing eyes. The low storage temperature increased the activity of hydrolytic enzymes and of peroxidase during the first months of storage.