Description

Southern corn rust (SCR) is caused by the obligate fungal pathogen, Puccinia polysora (Ppoly) and causes substantial loss in corn yield worldwide (Sun et al., 2021). The spores of Ppoly are not able to overwinter in the Northern Plains so disease is introduced via wind-borne spores traveling up from the south. The first case of southern rust in North Dakota was reported in 2020 (Halvorson et al., 2021).

Tar spot, also caused by an obligate fungal pathogen, was first detected in the United States in 2015. The causative pathogen, Phyllachora maydis (Pmay) may overwinter in colder regions but there is still not conclusive evidence of this (Kleczewski et al., 2019). Tar spot can affect the plant’s ability to take in sunlight, thereby affecting yields (Drewitz, 2022).

This project was funded by the National Predictive Modeling Tool Initiative.

References

Sun, Q., Li, L., Guo, F., Zhang, K., Dong, J., Luo, Y., and Ma, Z. (2021) Southern corn rust caused by Puccinia polysora Underw: a review, Phytopathology Research 3, 25.

Halvorson, J., Kim, Y., Gill, U., and Friskop, A. (2021) First report of the southern corn rust pathogen Puccinia polysora on Zea mays in North Dakota, Canadian Journal of Plant Pathology 43, S352-S357.

Kleczewski, N. M., Donnelly, J., and Higgins, R. (2019) Phyllachora maydis, Causal Agent of Tar Spot on Corn, Can Overwinter in Northern Illinois, Plant Health Progress 20, 178-178.

Drewitz, K. (2022) Tar Spot in Corn, University of Minnesota.