Effects of Different Carbon Sources on Callus Growth and Accumulation of Triterpenoids in Birch(Betula platyphylla Suk.)

The fresh weight of birch callus in callus induction media supplement with 10-50 g·L~(-1)of sucrose, glucose and fructose showed an upward trend during the second subculture,20-30 g·L~(-1)sugar were optimum for increase of fresh weight in birch callus.The contents of triterpenoid increased during 0-15 or 20 d,and then decreasd during 15 or 20-25 d in callus induction media supplement of 10-50 g·L~(-1)glucose and fructose,but triterpenoid content showed increase trend when media were supplemented 10-50 g·L~(-1)sucrose.30 g·L~(-1) glucose,fructose and sucrose were suitable for triterpenoid accumulation.