Southern rust shows in ICIA corn results

Corn got off to a good start but met challenges halfway through the 2025 growing season in Iowa.

Results from the Iowa Crop Improvement Association yield trials showed the effects, with the result being “more of an average year,” said Ryan Budnik, ICIA executive director.

“We had one of the biggest starts to a season headed to an overwhelming bumper crop, and all of a suddenly midway through it was like a spigot shut off and disease grew,” Budnik said. “Southern rust took a hit on our yield especially where fungicide was not sprayed.”

Variability popped up again in this year’s corn crop.

“A lot of it was in the same locations as last year,” Budnik said.

Disease pressure and where rain fell - or didn’t - compounded situations, he said.

“The Nevada site didn’t get fungicide sprayed and it took a whammy on yield,” he said.

The central Iowa spot, planted May 8 and harvested Sept. 30, averaged 185.1 bushels per acre, ICIA reported.

Overall, ICIA’s central district averaged about 193 bu./acre.

“Rains were falling perfectly early and then stopped,” Budnik said. “Southern Rust took over and you could see how fast the corn dried down.”