Keywords: 
• gibberellin acid（GA₃） /
• mango /
• color /
• enzyme activity

Abstract: Mango fruits of mango variety ‘Hongguifei’with 80% maturity were collected from the mango trees aged 15 years old,and spray treated with gibberellic acid（ GA₃） solution at different concentrations of 0,0. 3,0. 5,1. 0,2. 0,3. 0 g·L^-1to observe their change in fruit color and its related enzyme activities.. The results showed that with storage,the mango fruits treated with GA₃ at different concentrations increased gradually in decay index,color a*value,carotenoid content,anthocyanin content,and activities of chlorophyll enzyme,phenylalanine ammonia lyase（ PAL） and chalcone isomerase（ CHI）,and declined gradually in the content of chlorophyll,and the fruit peel changed from dark to light green,and gradually to red or yellow. Compared to the control the treatment of GA₃ inhibited the change of color in the fruit peel at the concentrations of 0. 3,0. 5 or 1. 0 g·L^-1and evidently at 2. 0 or 3. 0 g·L^-1,but the latter had poor impact on the fruit appearance and flavor of the ripening mango fruit. Considering the overall effect of the treatments and the fruit appearance it is better to treat the mango fruits with GA₃ at a concentration of 1 g·L^-1. According to the preservation effect and exterior quality,1. 0 g·L^-1GA₃ solution was the appropriate for mango fruits.