Tar Spot: An Understudied Disease Threatening Corn Production in the Americas

Tar spot of corn has been a major foliar disease in several Latin American countries since 1904. In 2015, tar spot was first documented in the United States and has led to yield losses of approximately 4.5 million t annually. Tar spot is caused by an obligate pathogen, Phyllachora maydis, and thus requires a living host to grow and reproduce. Due to its obligate nature, biological and epidemiological studies are limited and impact of disease in corn production has been understudied. Here we present the current literature and gaps in knowledge of tar spot of corn in the Americas, its etiology, distribution, impact and management strategies as a resource for understanding the pathosystem. This review is intended to guide current and future research and aid in the development of more effective management strategies for this disease.This is a manuscript of an article published as Valle-Torres, J., T. J. Ross, D. Plewa, M. C. Avellaneda, J. Check, M. I. Chilvers, A. P. Cruz et al. "Tar spot: An understudied disease threatening corn production in the Americas." Plant disease 104, no. 10 (2020): 2541-2550. doi:10.1094/PDIS-02-20-0449-FE. Posted with permission