Gibberellin retards chlorophyll degradation during senescence of Paris polyphylla

Chlorophyll (Chl) degradation was found to be related to the endogenous gibberellin (GA) content in shoots during senescence in the perennial plant Paris polyphylla var. yunnanensis (Franch.). Treatment with gibberellic acid (GA3) significantly increased the content of endogenous GAs (GA4 + GA7), retarded the senescence of shoots, and the degradation of proteins and Chl. Chlorophyllase, Mg-dechelation and peroxidase activities increased more in control plants than in those treated with GA3. GA3 treatment also protected lipoxygenase activity, which decreased significantly in control plants.