University of Minnesota researchers found 14 previously unreported species of Phytophthora in the state. These devastating water molds are known for causing extensive damage and economic losses to nurseries, forest stands and landscapes worldwide.
The researchers, whose findings were recently published in the Canadian Journal of Plant Pathology, surveyed Minnesota nurseries, forest systems and waterways in order to describe which species are present in Minnesota and where they occur.
Funding for this project was provided by the University of Minnesota's Minnesota Invasive Terrestrial Plants and Pests Center, supported by the Minnesota Environment and Natural Resources Trust Fund as recommended by the Legislative-Citizen Commission on Minnesota Resources.
"This research is incredibly important to protect the urban and natural forest systems in Minnesota. As we've learned from other devastating forest pathogens, early detection is the key to mitigating large economic losses," said lead author Nickolas Rajtar, a post-doctoral associate in the College of Food, Agricultural and Natural Resource Sciences.
The researchers found:
- During the sampling years of 2020-2023, 22 species of Phytophthora were detected around the state, including 14 species that were previously unreported in Minnesota.
- Nursery material coming from other states has the potential to carry pathogens, specifically Phytophthora. The growing season for Minnesota nurseries is limited, and many of the nurseries in the state ship in material from other states.
- There has been little to no research on the Phytophthora species found in forests or waterways in Minnesota. Traditionally, forests and waterways are often overlooked as avenues for Phytophthora detection.
"The genus of Phytophthora translates to 'plant destroyer' in Greek. With over 5,000 hosts, including trees, crops and ornamental plants, Phytophthora causes some of the world's most destructive plant diseases such as sudden oak death as well as the root rot, decline and mortality of many woody species," said co-author Robert Blanchette, a professor in the College of Food, Agricultural and Natural Resource Sciences.
Next, the researchers plan to test the pathogenicity of the newly detected Phytophthora species to better understand how easily they can spread disease to various hosts. They will also continue to monitor for new species in nurseries, forest systems and waterways in Minnesota.
About the College of Food, Agricultural and Natural Resource Sciences
The University of Minnesota's College of Food, Agricultural and Natural Resource Sciences strives to inspire minds, nourish people, and sustainably enhance the natural environment. CFANS has a legacy of innovation, bringing discoveries to life through science and educating the next generation of leaders. Every day, students, faculty, and researchers use science to address the grand challenges of the world today and in the future. CFANS offers an unparalleled expanse of experiential learning opportunities for students and the community, with 12 academic departments, 10 research and outreach centers across the state, the Minnesota Landscape Arboretum, the Bell Museum, and dozens of interdisciplinary centers. Learn more at cfans.umn.edu.
About the Minnesota Invasive Terrestrial Plants and Pests Center
The Minnesota Invasive Terrestrial Plants and Pests Center was founded by the Minnesota Legislature to research the prevention, detection and control of terrestrial invasive species. MITPPC researchers use transformative science to prevent and minimize the threats posed by land-based invasive plants, pathogens, and pests. Founded in 2015, MITPPC is the only research center of its kind in the country, and the center's work to protect the state's native prairies, forests, wetlands, and agricultural resources benefits all of Minnesota and beyond. MITPPC receives program support from the Minnesota Environment and Natural Resources Trust Fund as recommended by the Legislative-Citizen Commission on Minnesota Resources. Learn more at mitppc.umn.edu.
