Uncovering the environmental conditions required for Phyllachora maydis infection and tar spot development on corn in the United States for use as predictive models for future epidemics

Richard W Webster; Camila Nicolli; Tom W Allen; Mandy D Bish; Kaitlyn Bissonnette; Jill C Check; Martin I Chilvers; Maíra R Duffeck; Nathan Kleczewski; Jane Marian Luis; Brian D Mueller; Pierce A Paul; Paul P Price; Alison E Robertson; Tiffanna J Ross; Clarice Schmidt; Roger Schmidt; Teryl Schmidt; Sujoung Shim; Darcy E P Telenko; Kiersten Wise; Damon L Smith

doi:10.1038/s41598-023-44338-6

Uncovering the environmental conditions required for Phyllachora maydis infection and tar spot development on corn in the United States for use as predictive models for future epidemics

Sci Rep. 2023 Oct 10;13(1):17064. doi: 10.1038/s41598-023-44338-6.

Authors

Richard W Webster^#¹, Camila Nicolli^#², Tom W Allen³, Mandy D Bish⁴, Kaitlyn Bissonnette⁴, Jill C Check⁵, Martin I Chilvers⁵, Maíra R Duffeck⁶, Nathan Kleczewski⁷, Jane Marian Luis⁶, Brian D Mueller², Pierce A Paul⁶, Paul P Price⁸, Alison E Robertson⁹, Tiffanna J Ross¹⁰, Clarice Schmidt⁹, Roger Schmidt¹¹, Teryl Schmidt², Sujoung Shim¹⁰, Darcy E P Telenko¹⁰, Kiersten Wise¹², Damon L Smith¹³

Affiliations

¹ Department of Plant Pathology, North Dakota State University, Fargo, ND, 58108, USA.
² Department of Plant Pathology, University of Wisconsin-Madison, Madison, WI, 53706, USA.
³ Delta Research and Extension Center, Mississippi State University, Stoneville, MS, 38776, USA.
⁴ Division of Plant Science and Technology, University of Missouri, Columbia, MO, 65211, USA.
⁵ Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI, 48824, USA.
⁶ Department of Plant Pathology, The Ohio State University, Wooster, OH, 44691, USA.
⁷ Department of Crop Sciences, University of Illinois, Urbana, IL, 61801, USA.
⁸ Macon Ridge Research Station, LSU AgCenter, Winnsboro, LA, 71295, USA.
⁹ Department of Plant Pathology, Entomology, and Microbiology, Iowa State University, Ames, IA, 50011, USA.
¹⁰ Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, 47907, USA.
¹¹ Nutrient and Pest Management Program, University of Wisconsin-Madison, Madison, WI, 53706, USA.
¹² Department of Plant Pathology, University of Kentucky, Princeton, KY, 42445, USA.
¹³ Department of Plant Pathology, University of Wisconsin-Madison, Madison, WI, 53706, USA. damon.smith@wisc.edu.

^# Contributed equally.

Abstract

Phyllachora maydis is a fungal pathogen causing tar spot of corn (Zea mays L.), a new and emerging, yield-limiting disease in the United States. Since being first reported in Illinois and Indiana in 2015, P. maydis can now be found across much of the corn growing regions of the United States. Knowledge of the epidemiology of P. maydis is limited but could be useful in developing tar spot prediction tools. The research presented here aims to elucidate the environmental conditions necessary for the development of tar spot in the field and the creation of predictive models to anticipate future tar spot epidemics. Extended periods (30-day windowpanes) of moderate mean ambient temperature (18-23 °C) were most significant for explaining the development of tar spot. Shorter periods (14- to 21-day windowpanes) of moisture (relative humidity, dew point, number of hours with predicted leaf wetness) were negatively correlated with tar spot development. These weather variables were used to develop multiple logistic regression models, an ensembled model, and two machine learning models for the prediction of tar spot development. This work has improved the understanding of P. maydis epidemiology and provided the foundation for the development of a predictive tool for anticipating future tar spot epidemics.

Publication types

Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

Illinois / epidemiology
Phyllachorales
Plant Diseases* / microbiology
United States / epidemiology
Zea mays* / microbiology

Supplementary concepts

Phyllachora maydis