Abstract: Glycine soja often grow in shrub-shaded environments, but the mechanisms for adapting to shading have not been reported. Gibberellins (GAs) are a group of hormones that regulates shade avoidance. In order to study the effects of GA3 on the shade avoidance of Glycine soja, the phenotype of Glycine soja under white light and shad⁃ing after GA3 and GA synthesis inhibitor (paclobutrazol, PAC) application were analyzed. Expression of genes regu⁃lating photosynthetic pigment biosynthesis, GsCAO, and photosynthetic electron transport, GsPSAE and GsPSAG,were analyzed. The results indicated that photosynthetic pigment content of shading Glycine soja after PAC pretreatmentwas significantly higher than that of the control, while GA3 pre-treatment were opposite. chlorophyll fluo⁃rescence parameters suggested that PAC pre-treatment could enhance the shade-resistant while GA3 pre-treatment would make Glycine soja more sensitive to shade. Further research demonstrated that the expression of photosynthet⁃ic pigment biosynthesis gene GsCAO, photosynthetic electron transport genes GsPSAE and GsPSAG had an effect on enhanced shade-resistant of Glycine soja.

Key words: Glycine soja, shade, gibberellin (GA3), paclobutrazol (PAC), photosynthetic pigment gene