Sucrose synthase is a key enzyme in sucrose metabolism.In this study,we investigated the function of SUS family in Arabidopsis by using reverse genetics method.AtSUS3 was silenced in mRNA level by RNA interference technology.Using pure transgenic lines,we observed plants bolting rate,analyzed SUS,SPS,INV and CesA activity,detected soluble carbohydrate content and tested expression pattern of glycometabolism genes.(1)Comparison to wild plant,transgenic lines promote early bolting on an average of 2~3 d and ahead of time to complete bolting about 3~4 d.(2)Growth days after flowering (DAF) have significant impact on sucrose and glucose contents,but the impact on the fructose content does not significantly.5 DAF,the glucose content of the wild-type and transgenic line SUS3-15 is significantly higher than that of transgenic line SUS3-2.15 DAF,the glucose content of the transgenic lines is significantly lower than wild-type.(3)The growth days after flowering have a significant impact on SuSy,SPS and INV activities.With time extending,SuSy activity in the wild-type is significantly lower than that in the transgenic lines,but the SPS and INV activities are opposite.(4)We also detected that interfering AtSUS3 has different degrees impact to mRNA expression pattern in other sucrolysis genes.In 5 DAF transgenic siliques,the expression of AtCesA1,AtCesA7 and AtCINV1 are higher than that in wild siliques.In 15 DAF transgenic siliques,the expression of AtCesA1 and AtCesA7 are also higher than that in wild siliques,but the expression of AtCINV and AtCwINV are lower than that in wild siliques.These results indicated that transgenic plants have not developed anormally in normal culture conditions after AtSUS3 with RNA interference.It might be promote whole SuS activity to improve by other homologue SuSy genes and sucrolysis genes expression lever increase.All these reasons might facilitate siliques maturation.