Abstract: Many species in the family Tephritidae are quarantine pests worldwide. Usually, identification of the tephritid fruit flies is mainly based on external morphological characteristics of adults. In this research, the immatures (including egg, larva and pupa) and adult debris (including leg, wing, head, thorax and abdomen) of Bactrocera dorsalis (Hendel) were used to develop a rapid identification technique for tephritid fruit flies based on DNA barcoding technology. The other four tephritid fruit fly species, i.e., B. correcta, B. cucurbitae, B. tau and B. minax, were used to verify the feasibility of the fruit fly identification technique developed. The results showed that the nucleotide sequence identity of the partial COⅠ gene between the immatures or adult debris of B. dorsalis and the target gene from GenBank database is 99.51%-99.84%, while between other four tephritid fruit fly species and the target gene from GenBank database it is 100%, 100%, 99.81%-99.83% and 100%, respectively. Neighbor-joining tree was established based on the analysis of COⅠ gene sequences. The target species and the corresponding species in the database cluster in the same branches. All bootstrap values of the original divergence within one species are 100%. The intra- and inter-species genetic distances were calculated with MEGA version 5.0 software using the Kimera 2-Parameter model. The intraspecies genetic distances are 0.0000-0.0041, with an average of 0.0019. The interspecies genetic distances are 0.0597-0.2363, with an average of 0.1693. There is no overlap between intra- and inter-species genetic distances. The results indicated that the developed DNA barcoding identification techniques based on the partial COⅠ gene can provide a rapid and accurate method for identification of immatures or adult debris of tephritid fruit fly species.

Key words:  Bactrocera dorsalis, DNA barcoding, fruit fly, immature, adult debris, mtDNA COⅠ gene, identification