Much of the corn in the South is being harvested now, and it has been a year filled with Northern corn leaf blight and Southern rust, two diseases growers need to stay ahead of to reach the crop's highest yield potential this year.
"The current weather patterns coupled with associated delays in harvest are likely to result in increased levels of mycotoxins from infection by specific fungi," reports Bob Kemerait, University of Georgia Cooperative Extension plant pathologist, this week.
For growers with late-planted, irrigated corn with the potential for high yields, he said, it is important to protect corn with a fungicide against Southern corn rust and Northern corn leaf blight. "I believe that 'VT/first tassel' is an appropriate time to begin fungicide applications on corn planted in the spring, tassel is likely late in many cases for late-planted corn," he said. "I would tend to focus on the V5-V6 growth stages based upon current studies we have in the field. We have a number of good fungicides labeled on corn."
Asian soybean rust
Asian soybean rust has been found across the Coastal Plain in kudzu and in soybean fields in south Georgia. Soybean rust is also confirmed to be progressing across much of Alabama, approaching the border with central-western Georgia. "Bottom line is that weather conditions are excellent for development and spread of rust and the crop is at susceptible growth stages," he says.
Any soybean growers with beans that have reached the late-bloom-early pod development stages R2-R3 should strongly consider applying a fungicide to the crop. "Fungicides are typically being applied with dimilin and boron, and I have not heard of any problems adding an insecticide for kudzu bugs to the mix," he said.
For more information on Asian soybean rust and its spread this year, go to www.sbrusa.net.