Fungicide Use in Corn
PHOTO COURTESY OF BASFAerial application has been the main application technique for applying a fungicide between the VT and R2 stage of corn growth. “Photosynthesis is the driving engine for energy production in plants,” said Jennifer Holland, Ph.D., technical market specialist, BASF. “An increase in net photosynthesis means the plant has the ability to create more energy for use in the reproductive stages, which can lead to higher yield potential.”
There are “three pillars of plant health,” which can be affected by a fungicide, and the three are disease control, growth efficiency and stress tolerance.
Growth efficiency relates to benefiting the corn plant’s utilization of nitrogen fertilizer, and stress tolerance means the plant won’t be weakened and lower photosynthesis, according to Holland.
BASF reported, “In the study, conducted under water-stressed conditions, plants treated with a fungicide were nearly 30 percent more efficient at net photosynthesis than the untreated plants. The fungicide-treated plants were able to handle stress better than untreated plants, which can lead to higher yield potential.”
Syngenta also recently reported that corn treated with its fungicide, Quilt Xcel, during 2012 better tolerated drought. The company provided its version of what is going on to help the plant tolerate the heat and lack of water. The fungicide was “shown to reduce stomatal conductance, or the passing of water through the plant stomates, the natural openings in plants that allow exchange of water and gasses. This improves a plant’s water use efficiency. As plants regulate water loss more efficiently, soil moisture is conserved and plants are better equipped to tolerate periods of hot, dry weather.”
Syngenta also said its long-term evaluation of corn receiving the late-season fungicide application shows plants stay green longer, have corn ears that grow bigger, experience extended grain fill and have stronger stalks.
In fields infected with gray leaf spot or southern rust, Bradley has also looked at a late-season fungicide application reducing stalk rot. Again, in general, if disease pressure justified a fungicide application, then stalk rot problems could be reduced compared to untreated disease infected corn plants. But hybrids resistant to the diseases were less likely to show much improvement in stalk quality, he explained to the Crop Management Conference crowd in Columbia, Mo.