The recent detection of a bacterium deadly to vegetable crops has prompted the Wisconsin Department of Agriculture to examine geraniums in greenhouses across the state.
Recent detection of the bacteria Ralstonia solanacearum, which has been plaguing geraniums in area greenhouses, has local potato farmers concerned. The bacterium is the agent in the Brown Rot and poses a threat to vegetable crops.
The bacteria was first was introduced to Wisconsin from infected geranium clippings imported from Kenya. One strain of the bacteria can cause the destruction of potato crops by inhibiting water movement within the plant.
“While there are many strains of the Ralstonia solanacearum bacteria, laboratory tests confirmed that geraniums in one greenhouse were infected with the strain which is extremely destructive to potatoes, tobacco, peppers, tomatoes and eggplant,” said Nick Neher of the Department of Agriculture.
With Wisconsin ranking number three in potato growing, officials say prevention of the disease is critical to the state’s agricultural industries.
“If the bacterium gets into a potato crop it will cause the plants to die as well as becoming an export barrier,” said Jane Larson, public information specialist for the Department of Agriculture. “Neither potatoes nor seeds could be shipped out of the state.”
Inspectors from the Department of Agriculture and the United States Department of Agriculture’s Animal and Plant Health Inspection Service have been testing the infected geranium plants, and precautions have been made to prevent the further spread of the disease.
“All the infected plants have been removed and destroyed,” Larson said. “The greenhouses are being disinfected.”
Brian Hudelson of the University of Wisconsin’s Plant Pathology Department played a key role in first identifying the presence of the bacteria in Wisconsin.
Hudelson studied a similar case in 1999 when imported geranium plants from Guatemala were found infected with a strain of the bacteria.
“Ralstonia solanacearum can be transferred through ground water or gardening tools,” Hudelson said. “This particular race of the bacteria is more adapted to colder temperatures than usual races which are mostly found in warm climates.”
Hudelson said that despite the low temperatures outside, the bacteria might be able to survive within storage, resulting in the production of infected seeds.
The Wisconsin farming community has shown some response to the threat of the Brown Rot disease. In the next three days the Wisconsin Potato and Vegetable Growers Association will hold a convention in which research and information on current agricultural issues will be presented.
“Information will be given about the bacteria,” said Tamas Houlihan spokesperson for the WPVGA. “It has thus far not been a major concern, but we’ll be more knowledgeable after this week.”
In the meantime the USDA and the Wisconsin Department of Agriculture is continuing research in order to develop more effective processes of preventing the spread of Ralstonia solanacearum.
“We don’t have a lot of experience with this organism, so we have a lot of questions,” Hudelson said.
