1 College of Sciences, China Agricultural University, Beijing, People's Republic of China.
2 Risk Assessment Laboratory for Bee Product Quality and Safety of Ministry of Agriculture, Institute of Agricultural Research, Chinese Academy of Agricultural Sciences, Beijing, 100093, People's Republic of China.
3 Plant Protection Station, Beijing, People's Republic of China.
4 Institute of Agricultural Research, Taian, Shandong, People's Republic of China.
5 College of Sciences, China Agricultural University, Beijing, People's Republic of China. Electronic address: wangchengju@cau.edu.cn.