PCR and isothermal-based molecular identification of the stored-product psocid pest Lepinotus reticulatus (Psocoptera: Trogiidae)

Psocids of the genera Liposcelis and Lepinotus (Psocoptera) are well known small, soft-bodied stored-product pests that are difficult to identify using morphological characteristics, particularly the immature stages. Methods for quick, sensitive, and accurate identification of stored-product psocid species belonging to these genera are required for identification, discrimination, pest management, and inspection, and quarantine of imported grain. A specific primer set, RetCO1F/RetCO1R, was designed by targeting consensus sequences from multiple alignments of the CO1 gene of Lepinotus reticulatus for use in end point PCR, SYBR Green qPCR, and HDA. Lepinotus and Liposcelis species were tested to confirm the primer specificity. The described primer set allowed accurate identification of L. reticulatus, producing an amplicon of 119 bp in the three described assays. The primer set yielded a detection limit as low as 10 pg, 100 fg, and 1 ng using end point PCR, SYBR Green real time PCR, and HDA, respectively. All tests are accurate, rapid, sensitive, and useful for L. reticulatus identification and have multiple applications including biosecurity and forensic entomology.

► We develop a specific primer set for identification of Lepinotus reticulatus. ► We use CO1 gene to design the specific primer set. ► Assays show no cross reactivity with other Lepinotus and Liposcelis species. ► We use three techniques: real time PCR, end point PCR, and HDA. ► This is the first report of molecular identification of Lepinotus reticulatus.