DNA Barcoding

Almost 1 million species of insects have been described. Accurate species identification is important to scientific research and insect management. Taxonomic identifications can be laborious and time consuming. They depend on proper preservation of the specimen. Identification to species often requires a taxonomic expert who has the time and the motivation to identify the insect of interest. Can new technology help identification of insects?

DNA barcoding is a technique for collecting short pieces of DNA that are diagnostic for a species. A good DNA barcode can be relatively easily produced from a small amount of insect tissue. Good barcodes unique identify a species and distinguish it from closely related species.

Once a barcode sequence that identifies a species is established, the sequence is placed in a library where it can be openly accessed by computer for a variety of studies. Every cell of every animal and plant contains DNA. Once barcodes are available, is not necessary to preserve the entire organism in order to identify it. The unique DNA barcode can be obtained from tissue samples or even excreted materials such as insect frass. DNA barcoding offers the potential of using the dust at the bottom of a grain bin to identify the species present in the grain, or to collect insect frass from a wood boring insect to determine what species of insect is boring into a tree. We can detect what plants and animals some insects are eating by DNA fingerprints of their gut content.

Along with the barcode library, new technologies that streamline DNA extraction from the sample and read the barcode from the DNA are being developed. Most of the tasks can be automated to the point that a scientists can enter a tissue sample to the system and get a computer printout of the barcode out the other end.

These advances are improving our ability to study ecological interactions. Scientists are working collectively across the globe to build better research tools that expand the quality and quantity of work that can be done. This research effort will probably lead to new areas of research that have not yet been imagined.

Wood boring insects can be identified by DNA barcodes of their frass