Published on Monday, June 22, 2015
In her fourth week of scouting central Indiana fields, sales intern Christy Kettler has been noticing some additional stressors to corn plants currently in the V5 growth stage. See her report below to learn more about the stink bug damage and yellow leaves she has been seeing, as well as her trap findings and what you can expect in the coming weeks.
Stink Bug Damage and Yellow Leaves for Indiana Corn
Christy Kettler | Sales Intern | Central Indiana
June 15- June 19, 2015
Stink bugs have made their way into many corn fields in Indiana. Stink bug damage appears as round or elongated holes in a straight line across the leaf, usually in corn around the V5 growth stage. These insects feed on leaf fluids by inserting their tubular mouth in the plant matter. Stink bugs can cause destruction of tissue, loss of entire leaf ends, or some deformities. These can lead to limited leaf area and reduced photosynthesis. Along with this concern is the concept that the plant is setting its number of rows of kernels on its ears at this stage. Any significant stress to the plant during V5-V6 stages can reduce yield.
Stink bug damage in corn at V5 stage.
In wet conditions with temperature variations, this damage can lead to infection in a corn plant. I found this situation on a central Indiana farm this week. It appeared as white smut or wart type growths on the leaves and stalks. The plants that were infected will more than likely not grow through this condition and cause a loss in yield.
Infection in corn plant at V5 stage.
Most corn around the state is still showing a yellow color due to excess water and difficulty with nutrient uptake. In poorly drained soils, these plants are now facing a stunted growth and may fall behind other areas of the field. The corn will look inconsistent through the field from many angles. The pattern is likely to follow tile lines, soils types, or elevation changes. Most soybeans have appeared to handle the wet conditions with temperature swings better than corn and have only suffered a slight population decrease on average.
The traps throughout north central Indiana have turned up fairly light. I have found two black cutworm moths, 10 European corn borer moths, and 23 unidentifiable moths. These 23 moths appear to be of no threat to the crop, but keep watch for egg masses and insect feeding in fields. Check Purdue Entomology and Agronomy updates for more information.
Look for my findings again next week!
If you have any questions about these findings or would like more information, please reach out to myself or your seed advisor.
Author: Denny Cobb
Categories: Agronomy, N Indiana
Tags: Beck's Hybrids, corn, Indiana, Agronomy, Beck's, Denny Cobb, Scouting, Christy Kettler, stink bug, crop damage, corn damage, yellow corn leaves