Walking into a field of corn and finding spots and lesions on the leaves can be an alarming experience. Leaf damage can be caused by many factors, including environmental stress, mechanical injury, chemicals and disease pathogens.
Correctly identifying the source of leaf damage is key to determining your options for protecting the yield potential of your corn crop.
While a majority of foliar diseases are caused by fungus and can be mitigated with fungicide, bacterial diseases that enter the plant through wounds caused by insects or weather damage cannot be treated. Spraying the wrong product, such as a fungicide, on a bacterial disease, is a waste of money and resources.
For accurate identification of disease, laboratory culturing and microscopic examination may be required. Your local Channel Seedsman will monitor for corn disease outbreaks as part of the vegetative stage of the Channel Field Check Up Series.
Timing and placement of fungicide control products should be considered with economics, yield potential, disease pressure and weather patterns in mind.
Yield potential depends on the corn plant’s ability to create energy from photosynthesis, and the leaves directly surrounding the ear are primary contributors. Keeping those leaves free from damaging foliar disease is vital.
When environmental conditions indicate susceptibility to high disease pressure, preemptive fungicide applications, made throughout the corn canopy prior to the spread of disease, can help protect yield potential.
Proper identification of disease pathogens and understanding your environment and potential exposure are necessary when making management decisions for your farm.
A good place to start is by selecting products that are tolerant to the pathogens that frequently occur in your area. For next year’s crop, consider the new Channel Protexus corn products that provide tolerance to five yield-robbing corn diseases.