Abstract: The sweetpotato whitefly, Bemisia tabaci (Gennadius), is a species complex that is considered an important agricultural pest because of its diversity in biotypes, capacity to transmit viruses, high resistance to chemicals and rapid physiological development. Its biotype status in Jiangsu, Guangdong and Yunnan provinces was determined by using mitochondrial DNA COI markers and correlated with their host plants and locations. Results indicated that, in Guangdong and Yunnan, the local unresolved biotypes and the already known biotypes of B. tabaci (B and Q) coexist, the former is relatively more dependent on its host plants than the invasive biotypes. No Q biotype of B. tabaci has been found in Guangdong and no local biotype has been found in Jiangsu in this study. Multitudinous host plants and the inherent polyphagous characteristics enhance the wide invasion of B and Q biotypes in different counties.

Key words: Bemisia tabaci, biotype, host plant, geographical location, China