Studies on Original Plant of Traditional Chinese Drug "Bai Zhi" (Radix Angelicae Dahuricae)and Its Closely Related Wild Plants Ⅳ.Discussion on Original Plant and Cultivation History of Traditional Chinese Drug "Bai Zhi" and Evolution Studies on Original Plant of Traditional Chinese Drug "Bai Zhi"(Radix Angelicae Dahuricae)and Its Closely Related Wild Plants Ⅱ.Karyological and Pollen Morphological Studies on "Bai Zhi" and Closely Related Wild Plants Studies on Original Plant of Traditional Chinese Drug "Bai Zhi"(Radix Angelicae Dahuricae ) and Its Closely Related Wild Plants Ⅰ. Morphological and Anatomical Studies on "Bai Zhi" and Closely Re lated Wild Plants Studies on Original Plant of Traditional Chinese Drug "Bai Zhi" (Radix Angelicae Dahuricae)and Its Closely Related Wild Plants Ⅲ.Comparson of Coumarins of"Bai Zhi"with Those of Closely Related Wild Plants Optimization of extraction technology for Asteris Radix et Rhizoma in Zibai Zhisou Capsules with orthogonal test