Abstract: The effect of treatmentwith 50 mg·kg^{- 1} GA₃ solution for 30 min on lignification and endogenous hormone levels in postharvest bamboo (Phyllostachys praecox f. preveynalis) shoots were investigated. Results showed that the activities of phenylalanine ammonia lyase ( PAL) , cinnamate 4-hydroxylase (C₄H) and peroxidase ( POD) increased initially and declined later during the 30 days storage at 2 ℃. The lignin content and firmness continuously increased, but edible rate decreased gradually. The contents of GA₃ and IAA declined continuously, where as ABA content increased firstly and then declined. The activities of PAL, C₄H and POD were correlated with the rate of ABA /GA₃. Exogenous GA₃ treatment increased endogenous level of GA₃ content and decreased the rate ofABA /GA₃ aswell as inhibited the increase of PAL, C₄H and POD activities in bamboo shoots. The firmness and lignin content in GA₃ treated bamboo shoot were lower than those of control, while the edible rate was higher than that of control. It is suggested that GA₃ treatment retarded lignification through decreasing the rate of ABA /GA₃ in postharvest bamboo shoots.

Key words: Bamboo shoot, GA₃ , Hormone, Lignification