An assay to reliably achieve Tar Spot symptoms on corn in a controlled environment

Tar Spot continues to threaten U.S. corn production (Telenko et al., 2022). A reliable assay under controlled conditions is needed to study the epidemiology and management of Tar Spot. Researchers have reported controlled environment infections, but incidence and severity were low and the ability to screen germplasm has not yet been reported. In this paper, we describe a controlled environment assay that reliably achieves Tar Spot symptoms on corn plants allowing differentiation of susceptible and resistant germplasm.