General Information

Phytophthora rot is caused by an oomycete (fungus-like organism), Phytophthora sojae and can cause seed rots, pre- and post-emergence damping off early in the season although infection can occur at any stage of development in soybean. Symptoms include mushy and water-soaked stems and stunted or wilted seedlings. Infection is favored by wet conditions after planting, but is more common in warmer soils (57 to 77 °F) than Pythium species.

  • Resistant cultivars
  • Seed treatments containing metalaxyl or mefenoxam. Links to Seed Treatment Fungicide Efficacy Table – mobile version or pdf
  • Improved drainage and tillage may also help manage disease when warranted

Phytophthora root rot

Phytophthora root rot 2

Phytophthora root rot (oomycete: Phytophthora sojae)