I received a call early Tuesday about a Victoria county corn field with purple/red leaves below the ear. When I visited the field, I found what looked similar to the corn stunt we saw last year, but most of the discolored leaves were at or below the ear. Since looking at this field we have found other fields in Victoria and Calhoun county with similar symptomology.
I don’t think this is Corn Stunt since we have not been finding the corn leafhoppers. Other options include nutrient deficiency. The ears looked normal and seem to be progressing well just beginning to dent.
Leaves from this field were taken to Dr Tom Isakeit, Plant Pathologist in College Station, We should hear back from them next week.
What we did find on a few leaves appeared to be southern rust. This was confirmed by Dr Tom Isakeit in College Station. Management decisions for southern rust should be based on crop maturity and disease severity. There is no economic threshold. The key is to protect the leaves above the ear so they can continue to photosynthesize normally. 
Read more on Southern Rust here: https://agrilife.org/mid-coast-ipm/files/2025/05/southern-rust-of-corn-and-its-management-in-south-texas-1.pdf
