LIFE STAGE INDEPENDENT IDENTIFICATION OF FRUIT FLIES (DIPTERA: TEPHRITIDAE) USING 28S RDNA SEQUENCES

Abstract

With well over 500 species, Bactrocera is one of the most species-rich clades within the dipteran family Tephritidae, the true fruit flies. In quarantine and plant protection activities, their immature stages are metwith and diagnosis of these is important. For this purpose molecular diagnosis becomes handy, because it is independent of sex, color morphs and life stages. Alignment of the sequences of 28S rDNA from various life stages of the four species of Bactrocera shows that the molecular identification is independent of life stages and polymorphism of the target species. This study evaluated the utility of 28S rDNA for the quick and accurate species diagnosis of eggs, larvae, pupae and adults of all the Bactrocera spp. studied. The phylogram for the Bactrocera spp. suggests that B. tau is phylogenetically distant from the rest of the three species viz. B. dorsalis, B. zonata and B. correcta, which was supported by 100% bootstrap value. Moreover B. dorsalis, B. zonata and B. correcta had maximum sequence identity (98%) with very few variable sites in the 28S rDNA sequences. Even though, 28S rDNA region will have high reliability for species identification in these species studied and it was never reported before. This study indubitably proved the utility of 28S rDNA for the quick and accurate species diagnosis of egg, larva, pupa and adult of B. zonata Saunders, B. tau Walker and B. dorsalis Hendel.