College of Agricultural and Life Sciences potato experts at the University of Idaho are reviving a task force to help growers address a flare-up of bacterial ring rot disease.
Phillip Nolte, a University of Idaho Extension seed potato specialist at Idaho Falls, says the disease is reaching levels not seen in a decade. Mainly a threat to the appearance and storage of spuds, bacterial ring rot is not associated with any human health concerns.
"It's a cyclic thing," says Nolte. "We last saw problems in 2002, and there was an earlier flare-up in the mid-1990s."
Growers then controlled the disease and largely eliminated it by setting up their sanitation practices while cutting seed during spring planting and thoroughly cleaning and disinfecting all equipment and storages between crops," he adds.
The same practices will control the current outbreak, he believes.
The task force, which he leads, will help the potato industry, state and UI experts assist growers in tackling the disease and prevent the problem from becoming worse, he says.
Early monitoring shows that infection rates are heavy in some fields, but more monitoring is needed to determine the regional impact. Harvest will provide the most detailed information on the extent of the disease.
In cases where monitoring shows a significant problem with bacterial ring rot, Nolte says growers should delay harvesting until later in the season. That's because infected potatoes will rot in the soil and fewer will have to be sorted out before storage.
The cyclic nature of bacterial ring rot's appearance has much to do with relaxed vigilance by both seed potato producers and commercial growers, Nolte says. "After it appears, everyone is very aware and aggressive in their sanitation programs. Then we don't see bacterial ring rot for several years and people get complacent."
The disease is spread to healthy tubers when a contaminated potato leaves inoculum seed cuttings and handling equipment. It can remain viable in dried bacterial slime and in dried potato sap on equipment and storage surfaces for many years if not properly disinfected.