Consultants HONG Mengmin, Institute of Plant Physiology & Ecology, Chinese Academy of Sciences, Shanghai, China LU Yonggen, South China Agricultural University, Guangzhou, China MIN Shaokai, China National Rice Research Institute, Hangzhou, China YUAN Longping, China National Hybrid Rice Research and Developmental Center, Changsha, China ZHAI Huqu, Chinese Academy of Agricultural Sciences, Beijing, China