Abstract: Our earlier study showed that Bemisia tabaci biotype Q in Shandong, China, originated from the Western Mediterranean rather than the Eastern Mediterranean. To uncover the invasion mechanism of biotype Q, we analyzed the genetic diversity of the Q-biotype populations from the Eastern Mediterranean using the mtCOI gene and 6 highly polymorphic microsatellite loci, and compared the diversity to that of the Western Mediterranean Q-biotype populations. The results showed that the genetic diversity indices of the populations from this region were as high as those from the Western Mediterranean, and did not exhibit a significant difference. However, genetic heterogeneity existed within the populations in the two regions. The comparison of the genetic structure of populations, in native ranges and with different invasiveness, will be helpful to further reveal the physiological and ecological mechanisms of the invading alien populations.

Key words:  Bemisia tabaci biotype Q, biological invasion, genetic diversity, mtCOI, microsatellites, Mediterranean region