PARMA, Idaho — Researchers have confirmed they can use machines that capture airborne spores to detect some of Idaho’s most devastating crop diseases before symptoms surface in fields.
They also demonstrated they can analyze samples in Parma and relay results to industry within 24 hours of receiving them.
University of Idaho plant pathologist James Woodhall is leading the effort to set up an extensive network of spore samplers throughout Idaho to give growers advance warning of the arrival of harmful pathogens.
Woodhall and a team of UI researchers conducted their initial trials with the spore samplers this growing season, operating three machines stationed at the university’s research and extension centers in Parma, Kimberly and Aberdeen.
Woodhall said the samplers suck spores into a different vial each day, with a capacity to collect samples for eight days before vials must be changed. The samples will be sent by overnight mail to Parma, where Woodhall will use a diagnostic approach known as real-time polymerase chain reaction to test for up to 12 pathogens affecting several crops. Results will then be emailed to industry sources — and eventually posted on a web page that will be developed for the project.
In the “dry run” conducted during the second week of September, Woodhall said testing confirmed the presence of white mold and “it looked like spore levels were increasing as we got to the end of the week.”
“It’s quite good for us to practice with a small number of spore samplers, doing this in real time,” Woodhall said.
In Parma, Woodhall said his sampler detected powdery mildew two to three weeks before the arrival of disease symptoms in sugar beets. Woodhall also demonstrated samplers can detect potato early blight, but he’s still refining the diagnostic test. Woodhall is also developing a test to detect fusarium in onions. He has received a $120,000 in USDA specialty crop block grant through the onion industry to purchase a fourth sampler for onion research.
The Northwest Potato Research Consortium contributed $16,000 to cover research and develop potato-specific primers. Andy Jensen, with the consortium, said potato growers are especially interested in research to verify whether the lack of spore detection by the samplers means it’s safe to skip spraying protectants. Jensen noted Woodhall will use untreated “sentinel” potato plots to determine if diseases may surface near a sampler, even when no spores have been captured.
Processors and fresh packing sheds within the potato industry have contributed funding toward nine additional spore samplers, which will be strategically placed in commercial fields to monitor for potato diseases next season. The Idaho Bean Commission has also financed a spore sampler to bolster the network, and UI has two more samplers on order.
Next season, Woodhall hopes to begin learning how many samplers are needed to adequately detect diseases, and how they should be distributed.
UI potato pathologist Phil Wharton was recently awarded a $200,000 specialty crop block grant to assess the relationship between spore levels, weather and potential disease severity. UI Extension seed potato specialist Kasia Duellman will help Wharton develop a website with a map of spore sampler locations, and ultimately “decision aids to help growers identify different risk levels.”
“I envision we will have something up and running by next summer that is bare bones, giving the basic information, and over time it will be refined,” Duellman said.