Alyssa Koehler, University of Delaware
Erin Sparks, University of Delaware

In conjunction with extreme spring rains, changes in farming practices such as reduced tillage, a push for earlier planting dates, and “green bridges'' from cover crops have led to a rise in maize seedling disease incidence and subsequent death. Pathogen surveys have identified Pythium species as one source of disease and an emerging threat to maize production. Economic impacts of Pythium can include increased production costs associated with replanting and season long reductions in plant vigor that lower yield potential due to smaller ears or completely barren plants. Patterns of Pythium infection are sporadic and there are no management strategies to combat Pythium once symptoms are observed, making it difficult for growers to overcome this threat. Improved management relies on filling knowledge gaps of Pythium distribution and abundance in field soil relative to climatic variability and quantifying the impacts to plant growth and mechanics. The objectives of this project are to 1) Characterize load and distribution of Pythium spp. in field soil; 2) Quantify the impact of Pythium infection on maize root-type specific growth; 3) Assess Pythium impact on plant mechanics. Through this research-only project, we will address the increased invasiveness of Pythium and provide a foundational understanding of Pythium pathogenesis. Improved understanding of host responses will provide a basis for developing mitigation strategies for Pythium-related crop losses to increase yield, productivity, and economic potential for maize producers.