1 Key Laboratory of Poyang Lake Environment and Resource Utilization Ministry of Education, School of Life Sciences, Nanchang University, Nanchang 330031, China; 2 Forestry College, Jiangxi Agricultural University, Nanchang 330045, China; 3 State Key Laboratory of Systematic and Evolutionary Botany, Chinese Academy of Sciences, Beijing 100093, China; 4 School of Ecology, Sun Yat‐Sen University, Guangzhou 510275, China; 5 Jiangxi Academy of Forest, Nanchang 330013, China †These authors contributed equally to this work. *Author for correspondence. E‐mail: xiangxg2010@163.com and xiangxg2018@ncu.edu.cn