Sweetpotato virus manifests in such low concentrations that classic detection methods are not reliable. Currently to identify sweetpotato viruses researchers must graft sweetpotato to a very susceptible host plant and wait for symptoms to manifest. This process can take a minimum of four months.
The International Potato Center (CIP for its acronym in Spanish) and Fera UK have been working over the past five years to develop a new tool that can eliminate the need for time and labor intensive detection methods. “The ClonDiag-array Tube is very sensitive,” says Dr. Jan Kreuze, CIP plant virologist. “CIP has been working extensively to identify all strains of sweetpotato virus, based on that knowledge we can amplify nucleic sweetpotato acids and use it to test for all known viruses.”
Still in the validation phase, this new technology promises to reduce the time of virus detection from four months or more to as little as three days. Tests can be done directly from the sweetpotato plant eliminating the need for grafting. Costs savings are significant. Current methods average $150 a sample while the ClonDiag-array Tube, at a price tag of $70 per sample, reduces cost by more than half.
Once a sample is ready for reading, virus detection will appear in the form of blue dots at the bottom of the tube. A photograph taken with a smartphone can be loaded into the companion app that provides detailed information of detected pathogens within seconds.
“This technology proves particularly beneficial when moving sweetpotato germplasm from country to country,” says Kreuze. Strict international standards for transporting germplasm are in place to help stave off the introduction of new pathogens that could potentially decimate a crop system. Current methods require lengthy quarantine while samples are tested for viruses. “Quarantine can take anywhere from six months to more than a year,” says Kreuze. “With results in as little as three days we are opening up the possibilities for researchers to access sweetpotato germplasm at a faster pace.”