Study on the physiological characteristics and ethylene production during plum fruit ripening and softening

Taking ethylene biosynthesis as a clue,changes of firmness,TSS and TA content,ethylene production,ACC and MACC content,the activity of ACC oxidase and ACC synthase were determined and the effect of ethylene on plum fruit ripening and softening were discussed.The results showed that firmness and TA content decreased and TSS increased during plum fruit ripening and softening.In the start-up stage of softening,ethylene production as well as ACC oxidase and ACC synthase activity increased slowly and linear correlations can be seen among them.The peak of ethylene appeared in the later stage of softening.The study proved that ethylene was not the promoter for plum softening,and other factors for promoting plum softening still existed.