Abstract: This study investigated the change 6-phosphogluconate dehydrogenase and succinic dehydrogenase and in the contents ofmetabolic substances in the activity of key enzymes for respiratorymetabolic pathway hexosephosphate isomerase, 6-zwischenferment, in the Japanese aralia (Aralia elata) seed dormancy-breaking p rocess under alternating temperature. Results showed that, after the seed was soaked in a 200 mg·L ^{- 1} GA₃ acetone solution for 12 hours, the α-amylase activity and the soluble sugar content in the seed increased significantly and reached the maximum on the 12 th day, whereas the soluble p rotein content decreased steadily since the initiation of stratification, down to the lowest point on the 12 th day. In the after ripening
process, the Japanese aralia seed mainly relied on glycolysis and tricarboxylic acid cycle for its energy supply through oxidation, the activity of key enzymes in phosphopentase pathway reached the maximum on the 8 th day, in GA₃ and stratification alternating treatment proceess, suggesting that the activation of this pathway also played a vital role in breaking the dormancy of the seed.

Key words: Aralia elata, After-ripening, GA₃, Stratification, Metabolic control