TarSpot1-(1).jpg

Concerted Battle with Tar Spot of Corn Continues

While seed choices are limited, plant pathologists urge growers to attempt to select hybrids for tar spot resistance and be ready to make fungicide applications at the first sign of the disease in their fields.

Corn producers in a growing number of states are preparing for a fight with tar spot, a fast-spreading, elusive fungal disease capable of devastating yield losses

Infestations of the fungus Phyllachora maydis, which originated in Central and South America, have spread quickly since first discovered in 2015 in 7 counties of northwest Indiana and 10 counties in north-central Illinois. In 2018 the disease began cutting yields in Indiana and other states as it continued to spread rapidly to surrounding states. Today it is present with confirmed or probable cases in 14 U.S. states and fields in Ontario, Canada. 

“For a disease which only turned up in the U.S. in 2015, it has spread remarkably fast,” says Steve Goodwin, USDA-ARS plant pathologist in West Lafayette, Ind. “I heard recently Iowa is the first state in the country to report it in all of its counties.

“Because of the original outbreak being near to the Great Lakes, everyone thought it would be limited to the cooler regions there, but that was wrong,” Goodwin says. “According to university Extension plant pathologists across the affected regions, the main driver is moisture rather than temperature. Infections have not been as severe in droughty areas, but are seen in beautiful-looking corn that hasn’t suffered from any other problems. And then it can come in hard and fast.”

Purdue University Extension plant pathologist Darcy Telenko has been working with Indiana and other area producers on tar spot since its first appearance and agrees moisture is a…

To view the content, please subscribe or login.
 Premium content is for our Digital-only and Premium subscribers. A Print-only subscription doesn't qualify. Please purchase/upgrade a subscription with the Digital product to get access to all No-Till Farmer content and archives online. Learn more about the different versions and what is included.

Dan crummett 0618

Dan Crummett

Dan Crummett has more than 35 years in regional and national agricultural journalism including editing state farm magazines, web-based machinery reporting and has an interest in no-till and conservation tillage. He holds B.S. and M.S. degrees from Oklahoma State Univ.

Top Articles

Current Issue

Cover_CTG_0822.jpg

No-Till Farmer

Get full access NOW to the most comprehensive, powerful and easy-to-use online resource for no-tillage practices. Just one good idea will pay for your subscription hundreds of times over.

Subscribe Now

View More

Must Read Free Eguides

Download these helpful knowledge building tools

View More
Top Directory Listings