Abstract:
Objective Mitochondrial genome and phylogeny of Bactrocera (B.) tuberculata were studied for advancement on the molecular markers design, species identification, and evolutionary genetics relating to the destructive fruit fly.
Methods High-throughput sequencing was applied to determine, assemble, join, and annotate the complete genome of B. (B.) tuberculata mitochondria. With the sequences on selected 20 species published on NCBI, the phylogeny of fruit flies was analyzed using the maximum likelihood method (ML).
Results The total mitochondrial genome sequence was 15 854 bp long containing 13 protein coding genes, 22 tRNA genes, 2 rRNA genes, and one non-coding control gene with 73.2% A+T. There were 3 755 codons in the 13 protein-coding genes. Of the 22 amino acid codons in the protein, UUA (leucine) had the highest frequency (N) of 387 and relative codon (RSCU) of 3.79. Aside from the phenylalanine (F) and threonine (T) that lacked pseuduracine (T) rings and the serine (S1) without a dihydrouracil DHU ring, the secondary structures of the remaining 19 tRNA genes shaped typically like a canonical cloverleaf. And the 22 genes had 178 mismatched G-U base pairs. Based on the mitochondrial analysis, the phylogeny of B. (B.) tuberculate, B. (B.) dorsalis, and B. (B.) carambolae were closely related and in the same branch as other subgenera. The result agreed with what was revealed by the morphological observation.
Conclusion For the first time, the complete mitochondrial genome of B. (B.) tuberculata was obtained with a GenBank accession number of MW 892726. The information secured on the structure and nucleotide composition of the mitochondria and the phylogenetic relation with other subgenera would aid further studies on the species identification, evolutionary biology, and pest control of the devastating pest.