Identification of two stem borers, Sesamia nonagrioides (Lep.: Noctuidae) and S. cretica by DNA barcoding

Two species of the genus Sesamia, Sesamia nonagrioides (Lefèbvre, 1827) and S. cretica Lederer, 1857, have been reported as agricultural pests in Iran. DNA barcoding was used to confirm morphological identifications and achieve a reliable and rapid species identification of these pests when the expertise is limited. Specimens were sampled from host plants of maize, sugarcane and rice in Khuzestan and Fars provinces and identified by classical taxonomy. The COI region was amplified from extracted DNA by appropriate primers and sequenced. The sequences were aligned and barcode gap, nucleotide divergence were calculated. Genetic distances between sequences of the two mentioned species and five closely related Sesamia species were evaluated based on a Neighbour-joining tree, using the Kimura 2-parameter distance model. Results could make a satisfactory species delineation and approved morphological identifications for S. nonagrioides and S. cretica. It is recommended to use these results for a rapid and precise species identification of these two species both in the immature and adults stages.