By Matt Reese
There is no question that 2019 has been a tough year for corn production in many parts of Ohio. Planting conditions were far from ideal and for most of the fields in the state the crop got a late start.
“From what I’ve seen in my travels, we all have battled with late planted corn, but in the past 4 to 6 weeks the corn has grown rapidly with the heat we’ve had. Most places around Ohio have decent moisture, though some places are hurting some. Overall things look pretty good. The crop has been growing fast,” said Brad Miller, CCA, Technical Agronomist for DEKALB and Asgrow in northern Ohio. “Corn has experienced a rapid accumulation of heat units, but I’m afraid with the late start we are going to see a little slower dry down after black layer. At black layer we are probably going to be seeing greater than 30% grain moisture levels and it will take a little longer for dry down. My hope is that we have a long open fall harvest season. We don’t want a short window for harvest.”
With the late planting season and high moisture levels early in the growing season, the potential for disease issues has also been a significant concern for much of Ohio’s corn crop.
“As far as disease goes, we are seeing some gray leaf spot. I think there was benefit from foliar fungicides, even with the later planting dates this year,” Miller said. “There is a saying in Ohio — don’t give up on a growing crop. I think we can take a disappointing start and turn it into a successful finish.”
Because of the disease issues, resistant hybrids have shown some advantages this year in terms of potential overall profitability.
“Our DEKALB Disease Shield hybrids are looking phenomenal. To be a Disease Shield hybrid, it has to have above average tolerance to gray leaf spot, northern corn leaf blight, southern rust, anthracnose stalk rot, and Goss’s wilt,” Miller said. “Products that are performing really well this year are DEKALB DKC55-53, DKC58-35, DKC61-98, and DKC64-34 RIB Brand Blends. Those four from early to late maturity are looking phenomenal this year.”
Even with genetic disease resistance, fungicides may still be a benefit.
“These products all have good natural tolerance to those five diseases, but it doesn’t mean they have zero response to fungicides. In those situations we can see benefit to fungicides from a plant health perspective as far as protecting that yield potential,” Miller said. “With fungicides you are reducing ethylene production in the plant. When a plant gets under any type of stress, ethylene production goes up and that is what triggers the plant to start to mature. That is one benefit you can see with a fungicide application even in the absence of disease.”
Dry weather in many parts of the state since July slowed the fungal diseases to some degree, but those diseases had a long, wet spring to multiply in fields, said Pierce Paul, a specialist in corn and small grain diseases with Ohio State’s College of Food, Agricultural, and Environmental Sciences (CFAES). He said gray leaf spot disease is the the most common corn disease across the Corn Belt, and northern corn leaf blight and tar spot, a new disease in Ohio, were also potential threats for corn this year.
Tar spot was detected for the first time in Ohio in 2018. The symptoms are raised circular, brown to black lesions scattered across both surfaces of the leaf. It is favored by moderate temperatures, high relative humidity, and extended periods of leaf wetness, and is often more severe in no-till, continuous-corn fields.
This article was contributed by Ohio Country Journal for DEKALB.