Abstract: In this paper,sweet sorghum and grain sorghum were used to analysis soluble sugar content,sugar content,fructose content and SS,SPS activity.The results showed that soluble sugar content and fructose content of stems in　the sweet sorghum are higher than in the grain sorghum at ripening period,sucrose content of stems in sweet sorghum is higher than grain sorghum at milky stage.The change of the activities of sucrose phosphate synthase (SPS) in the two types of sorghums follows a similar trend.The activities of SPS of stems significantly increased in the grain sorghum from the milky period to ripening period.The activities of sucrose synthase (SS) of stems in the grain sorghum is rising during whole growth period.The activities of SS of stems reached maximum in sweet sorghum at milky stage,obviously higher than the grain sorghum.Correlation analysis of sugar content and activities of sugar metabolism enzymes revealed that the efficiency of SPS synthesize sugar in sweet sorghum is higher than grain sorghum.The activities of SS and the fructose content in stems are obviously different in the two types of sorghums,the mode of action of SS is different.

Key words: Grain Sorghum, Sweet sorghum, SS, SPS, Sucrose, Fructose, Correlation analysis

CLC Number: 

• S514.01