Sara Muri, AgWeb Crops Online Editor
Have you checked your cornfields lately? Are all the stalks standing tall? If not, they could be suffering from stalk rot, a corn disease that causes weak stalks.
Gary Bergstrom, plant pathology professor at Cornell University, says this is the time of year farmers should begin looking for signs of stalk rot.
Bergstrom says the pathogenic microorganisms that cause stalk rot are always present in corn fields. But, it requires additional stress on the corn plants to cause the disease to populate.
"Those areas with very dry conditions during grain development are at the most risk,” Bergstrom says.
In addition to inadequate moisture during grain fill, Bergstrom says the prevalence of insect or other disease pressure will also encourage stalk rot.
Luckily, Bergstrom says, producers in New York have seen little foliar disease.
According to information published by the University of Minnesota, farmers should annually scout their fields for stalk rot. They suggest:
- Testing 20 plant in five different parts of the field
- Using the "pinch test,” which involves squeezing the lower portion of the stem
- Using the "push test,” which involves pushing the stalk at ear height 10" to the side
If the stalks are easily compressed during the pinch test or remain bent over during the push test, it is likely a field is suffering from stalk rot.
Plant pathologists at the University of Minnesota say if 10 to 15% of the plants in a field show signs of stalk rot, early harvest should be considered.
For More Information
Dry Weather May Lead to Stalk Lodging in Corn, Ohio State University
Time to start scouting for corn stalk rot and Remember to scout for corn stalk rots, Iowa State University
View photos of stalk rot symptoms, courtesy of Purdue University
You can e-mail Sara Muri at firstname.lastname@example.org.
This article appeared in the latest issue of AgWeb's Corn eNewsletter. To sign up for a free subscription, click here.