CAI, ZHUO-YU, Key Laboratory of Plant Resources Conservation and Sustainable Utilization & Guangdong Provincial Key Laboratory of Applied Botany; South China Botanical Garden; Chinese Academy of Sciences; Guangzhou 510650; Guangdong; China; Conservation Biology; Core Botanical Gardens; Chinese Academy of Sciences; Guangzhou 510650; Guangdong; China; University of Chinese Academy of Sciences; Beijing 100049; China, China