1. Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Danzhou City, Hainan Province, P. R. China
2. Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, P. R. China
3. Danzhou Investigation & Experiment Station of Tropical Crops, Ministry of Agriculture and Rural Affairs, Danzhou City, Hainan Province, P. R. China