Cytokinins Affect Respiration, Ethylene Production, and Chlorophyll Retention of Packaged Broccoli Florets

Abstract

Broccoli (Brassica oleracea L. var. italica `Citation') florets were treated postharvest with either benzyladenine or trans-zeatin at either 10 or 50 ppm before packaging in perforated polyethylene bags and storage at 16C. The most pronounced effects were observed with benzyladenine at 50 ppm. Compared to controls, respiration rate was reduced 50% and ethylene production increased 40% throughout the first 4 days of storage. Total chlorophyll content had dropped 60% in controls, but was unchanged in cytokinin-treated florets, which had a 90% longer shelf life than controls. These effects depended on the amount of cytokinin applied and were of greater magnitude with benzyladenine than with zeatin.