After the dormancy in whole winter, the stem color would be changed into fulvous. 3 single lines with over 1% steroid sapogenin have been selected from those lines with near 1% steroid sapogenin.

• 利用筛选出皂苷配基含量接近1%25的材料，选育出皂苷配基含量超过1%25的单株品系3个。