1 State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry and Northeast Forestry University, Beijing 100091, China; 2 Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China; 3 Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Yunnan 666303, China; 4 State Key Laboratory of Subtropical Silviculture, College of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou, Zhejiang 311300, China; 5 Department of Ecology and Environmental Science, UPSC, Umeå University, SE-90187 Umeå, Sweden *Authors for correspondence. Yan‐Jing Liu. E‐mail: yan.jing.liu@163.com; Qing‐Yin Zeng. E‐mail: qingyin.zeng@caf.ac.cn