Abstract:The study used seeds of Paeonia rockii treated with different concentrations of gibberellic acid (GA3) to investigate the effects of rooting and the variation of nutritious substances, enzyme activity and endogenous hormones content during different rooting stages to provide a basis for clarifying the mechanism of seed germination. The results showed that: (1) GA3 treatment could effectively promote the rooting of seeds. 300 mg/L GA3 treatment was the best to promote rooting with the highest rooting rates of 71.00% and made the first seed rooting time shorter 14.67 days than control treatment. (2) Compared with the control, GA3 treatment could promote hydrolysis of the starch, soluble sugar accumulation and soluble protein consumption of seeds in the first 15 days. It also could accelerate improvement of activity of peroxidase (POD) in the first 30 days. (3) During sand stratification process, abscisic acid (ABA) content decreased gradually, gibberellic acid (GA), zeatin riboside (ZR) and indole3acetic acid (IAA) contents increased first and then decreased. Compared with the control, GA3 treatment could increase the contents of GA, ZR and IAA which significantly improve dormancy breaking. The study found that GA3 treatment can regulate the contents of endogenous hormones, POD activity and the transformation of nutrients, thus seeds of Paeonia rockii can break dormancy and germinate in advance.