1. Laboratory of Mass Spectrometry, College of Chemistry, Central China Normal University, Key Laboratory of Pesticides and Chemical Biology, Ministry of Education, Wuhan, Hubei 430079, P. R. China
2. Guangdong Key Laboratory for Crop Germplasm Resources Prevention and Utilization, Agro-Biological Gene Research Center, Guangdong Academy of Agricultural Sciences, Guangzhou, Guangdong 510640, P. R. China
3. Center for Instrumental Analysis, College of Life Science and Technology, State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi University, Nanning, Guangxi 530004, P. R. China