Changes in sucrose synthetase and sucrose phosphate synthetase activities during storage of potatoes

Abstract

Sucrose synthetase in potatoes decreased sharply after harvest and remained low during warm storage. The activity increased slowly when the tubers were placed in cold storage and continued to increase after 30 weeks. Sucrose phosphate synthetase also decreased in warm-stored Norchip tubers, but it increased in Kennebec tubers. It increased quite rapidly in both varieties during the first few weeks of cold storage and then essentially leveled off. Both enzymes decreased during reconditioning of cold-stored tubers, but they tended to increase in Kennebec potatoes after prolonged reconditioning. Sucrose phosphate synthetase was much higher than sucrose synthetase in all stored tubers.