Cytochrome b gene as a potential DNA barcoding marker in ecoraces of tropical Tasar silkworm Antheraea mylitta Drury

"Background: Tropical Tasar silkworm Antheraea mylitta Drury plays a very crucial role in the economic development of the country employing around 9.76 million people in rural and semi-urban areas. Since the population of this species has spread over many states with varying environmental factors, the population has been isolated into many pockets, specifically adapted to that niche, and are called as “ecoraces”. Even though phenotypically these ecoraces may look similar to some level but the intra-generic genotypic variability between them is correlated to the economically important yield traits of their cocoons. The purpose of our study was to evaluate the effectiveness of Cytochrome b (Cyt b) gene of mitochondrial genome as a potential DNA barcoding marker for identification of these ecoraces as to are they really ecoraces, and attempts to establish the first country report of DNA barcode reference library of this silkworm species.
Methods and results: DNA was extracted from pupae of pure ecoraces collected from core ecozones. PCR amplicon was bead purified and further subjected to Sanger Sequencing. The parsimony tree was also created using the MEGA 11 software. The genetic distance, gene flow and relation among the ecoraces was evaluated. The conserved regions of Cyt b gene were identified along with the documentation of the mode and tempo of nucleotide variation and evolution.
Conclusion: The present study confirms the efficiency of Cyt b gene as a potential DNA marker for identification of ecoraces of Tasar silkworm and is the first country report on barcoding of A. mylitta Drury. Apart from being used as an early-warning system for ecological degradation, this knowledge will help in assessing the evolutionary relationship of these economically important ecoraces and identify their position in the process of evolution aiding in the assessment of conservation priorities."