A $2.7 million grant will help Northwest researchers determine whether insects causing zebra chip disease in potatoes come from outside the region or already live here.
The USDA Specialty Crops Research Initiative recently awarded the grant to Washington State University researchers, who will work with scientists from Oregon and Idaho.
Zebra chip causes infected potatoes to develop brown stripes that are most apparent when fried. The striped sections easily burn, leaving a bitter flavor, according to WSU.
WSU entomologist Bill Snyder said one group of psyllids enters the Northwest on weather fronts from elsewhere in the country. The other group is already in the area, surviving the winter on nightshade and related weeds.
Not knowing whether the local or distant psyllids are spreading the disease makes it difficult for farmers to predict whether they’ll have a bad or good zebra chip year, Snyder said.
“They don’t really know how to manage it, either, since they don’t know where the bad insects are coming from,” he said.
Snyder hopes to develop good prediction models to give farmers “real-time” information about the risk of seeing the insects turn up on their land.
If the local ones are causing the problem, researchers could monitor the weeds they use to survive the winter and report population increases, Snyder said. If outside psyllids are the culprit, the industry would monitor weather patterns and predict conditions for movement.
It’s also possible both psyllids are causing the disease, Snyder said.
“We just have known so little about the local psyllids,” he said. “A couple years ago, people thought there wasn’t even such a thing.”
The local psyllids may have been around for hundreds or thousands of years, Snyder said. They are different genetically from the ones entering the area.
The grant allows the researchers to expand the work that’s already been done across the region, he said.
“People already sample for psyllids in the different states throughout the year,” he said. “Now we’ll have one network for all three states and everyone will be readily sharing information.”
Project team leaders will meet with industry leaders and arrange to work in fields in upcoming weeks, Snyder said.
The project is slated to last five years. Snyder plans to have the first working risk prediction models within three years.