Study on the Suitable Harvest Period of Gastrodia elata Bl. in Tonghai Based on Principal Component Analysis

• WANG Haixiang, 
• DU Chunjiang, 
• WEI Qin, 
• HOU Ying, 
• XU Juan, 
• YANG Meng, 
• LIU Xiangyi, 
• SU Weigeng