Isolates of Phytophthora Sojae


Characterized isolates of Phytophthora sojae, a pathogen of soybean


Executive Summary:

Isolates of Phytophthora sojae were collected in Michigan for pathotype structure characterization and identification of EC50 (effective concentration to inhibit mycelial growth by 50%) for common seed treatment fungicides.



Phytophthora sojae is a pathogen of soybean that causes stem and root rot, resulting in major crop losses in most soybean growing regions. Current management techniques include fungicide seed treatments, however long-term use of fungicides can result in fungicide resistance. Understanding the pathotype structure and fungicide sensitivity of Phytophthora sojae can inform long-term fungicide and soybean variety selection and development.


Description of Technology:

Isolates of Phytophthora sojae were collected in Michigan to understand the local pathotype structure and common seed treatment fungicide sensitivity. Pathotype structure was characterized and the isolates were challenged with common seed treatment fungicides, including ethaboxam, mefenoxam, oxathiapiprolin, and pyraclostrobin, to identify the effective concentration to inhibit mycelial growth by 50% (EC50). These characterized isolates are maintained on V8 medium.


Key Benefits

  • Phytophthora sojae isolates for Michigan- and Midwest-based soybean research
  • Isolates are characterized for pathotype structure and common seed fungicide sensitivity



Research on Phytophthora sojae infection in soybean


Related publications:

Phytophthora sojae Pathotype Distribution and Fungicide Sensitivity in Michigan. McCoy et al., Plant Disease. 2022.


Protection Status: None


Tech ID: TEC2021-0068


Patent Information:


For Information, Contact:

Julia Miller
AgBio Technology Manager
Michigan State University