As of today, June 13, Southern Corn Rust has been positively identified in a field in Pulaski County.
A comprehensive list of suggested fungicides for control of Southern Corn Rust can be found on page 81 of the 2016 Corn Production Guide.
Based upon research trials conducted by the UGA Cooperative Extension, growers are most likely to see a yield benefit (and an increase in profit) from using a fungicide on field corn when:
1. Southern rust infects the crop (or in cases of severe outbreaks of northern or southern corn leaf blight) early in the season.
2. The grower has planted a variety that is susceptible to southern rust or when race of southern rust is present that is able to overcome the resistance found in a “resistant” variety.
3. The grower is able to apply the fungicide before it has spread significantly within the field.
4. The corn crop in the field has otherwise good-to-excellent yield potential.
5. Note: Severe outbreaks of northern corn leaf blight in some fields have also warranted treatment with fungicide. It is recommended that a grower consider use of a fungicide to protect a corn crop if northern corn leaf blight is affecting the crop as it reaches tasseling or the variety is known to be susceptible to this disease. A strobilurin or strobilurin-triazole combination will offer the best management of this disease when applied early enough.
As always, if you have any questions, please don’t hesitate to contact the Dooly County Extension Office.