An analysis of morphological and genetic diversity of mango fruit flies in Pakistan

Fruit flies of genus Bactrocera are important insect pests of commercially cultivated mangos in Pakistan limiting its successful production in the country. Despite the economic risk, the genetic diversity and population dynamics of this pest have remained unexplored. This study aimed to morphologically identify Bactrocera species infesting Mango in major production areas of the country and to confirm the results with insect DNA barcode techniques. Infested mango fruits from the crop of 2022, were collected from 46 locations of 11major production districts of Punjab and Sindh provinces, and first-generation flies were obtained in the laboratory. All 10,653 first generation flies were morphologically identified as two species of Bactrocera; dorsalis and zonata showing geography-based relative abundance in the two provinces; Punjab and Sindh. Morphological identification was confirmed by mitochondrial cytochrome oxidase gene subunit I (mt-COI) based DNA barcoding. Genetic analysis of mtCOI gene region of 61 selected specimens by the presence of two definite clusters and reliable intraspecific distances validated the results of morphological identification. This study by morphological identification of a large number of fruit fly specimens from the fields across Pakistan validated by insect DNA barcode reports two species of Bactrocera infesting mango in the country.