Abstract: 【Aim】The aim of the study is to test the validity of the VspI-, StyI- or StuI-based cleaved amplified polymorphic sequence (CAPS) markers of mitochondrial cytochrome oxidase I gene (mtCOI) for identification of Bemisia tabaci cryptic species Q and B. 【Methods】In this study, the mtCOI fragments from B. tabaci from China and abroad were sequenced and used to identify cryptic species. Based on the analyses of mtCOI sequences of 464 and 98 individuals from cryptic species Q and B, respectively, the restriction endonuclease enzyme VspI-, StyI-, or StuI-based CAPS markers was used to differentiate cryptic species Q and B for assessing its utility. The mtCOI sequences of B. tabaci cryptic species Q and B in GenBank were downloaded and the distribution of the recognition sites of VspI-,StyI-, and StuI- was analyzed. 【Results】The results showed that the individuals from China and abroad could be differentiated by using VspI-based CAPS markers effectively, but not by StyI- or StuI-based CAPS markers. The mtCOI sequence analysis showed that VspI-, StyI- or StuI-based CAPS markers could not differentiate cryptic species Q and B. 【Conclusion】VspI-, StyI- or StuI-based CAPS markers has limitations in identifying cryptic species Q from B.

Key words: Bemisia tabaci, cryptic species, mtCOI gene, cleaved amplified polymorphic sequence (CAPS), cryptic species identification