Changes in activities of superoxide dismutase, catalase and peroxidase during senescence of gladiolus florets

摘要

Treatments with sodium benzoate and n-propyl gallate, as free radical scavengers, slightly delayed the wilting of perianths in detached gladiolus (Gladiolus grandiflorus cv. Fujinoyuki) florets. Superoxide dismutase (SOD) activity of the perianths sharply decreased within 2 days after their full unfolding (DAU), when they commenced to wilt. The decrease of SOD activity was alleviated by treatments with 300μM cycloheximide (CHI), which prevented perianths from wilting. The specific activity of perianth catalase (CAT) did not markedly change, but CAT activity per perianth decreased concomitantly with wilting. CHI slightly decreased the specific activity of CAT. Perianth peroxidase (POD) activity sharply increased 1 DAU. This increase was almost completely suppressed by CHI treatments. These results indicate that free radicals are involved with the decline of SOD activity, increase in POD activity, and in the wilting process of gladiolus perianths.