When rotting, wilted ginger was reported to the Minnesota Department of Agriculture by specialty growers in central Minnesota in July 2024, UMN-PLPA researcher Milo Chiu and faculty member Devanshi Khokhani were ready to solve the case. Testing the samples, Chiu and Khokhani found Ralstonia pseudosolanacearum (Rps), a bacterial disease common in tropical growing regions like Hawai’i.
Chiu and Khokhani’s sequencing confirms the first outbreak of Rps in the mainland United States, and the Rps strain they found groups with isolates from recent bacterial wilt outbreaks in the Netherlands and Peru, suggesting that infected ginger seeds may be the common source of a number of outbreaks. More commonly a warm-weather pathogen, Rps is not able to survive the Minnesota winter’s cold temperatures, but farmers and gardeners should be aware that preliminary assays show that the UMN Rps isolate can infect nightshade crops such as tomatoes.
Further research in the Khokhani lab is investigating the ability of Ralstonia species to impact other crops, and the increased impact the disease could have in a changing climate.
This research received funding from MITPPC, the Minnesota Invasive Terrestrial Plants & Pests Center.