Dr. Bob Kemerait:
“1. Which growers are at highest risk? Because the rust (which was well established in the field) was found in Coffee County, (and Colquitt Co as of yesterday, Thursday, 6/10/21) I would say any corn in the southern Coastal Plain part of the state is at risk.
2. Should we recommend spraying? If corn has not reached VT tassel or is at R6 hard dough, do not spray. If the field has been sprayed in the last 2 weeks, don’t spray. If the field is being SCOUTED and no southern rust is found, I wouldn’t spray. That’s why you pay a scout…. I would recommend spraying if 1) tassel stage or beyond, 2) irrigated with high yield potential, 3) especially in SE GA around Coffee-Jeff Davis Counties, AND 4) field is not carefully scouted.
3. Do we expect spread of the rust? Yes! Weather is favorable and we have beaucoup corn this year in the state.
4. What to spray? Single mode of action products like tebuconazole, tetraconazole, azoxystrobin and pyrscloztrobin are good products for about 2 weeks or so. Mixed mode of action products are better and last longer. Are there “best” products? Yes, but NOTHING works once rust is well established in a field of corn.”
Peanut Fungicide Info
Here is a summary of last year’s Cook Co. Peanut Fungicide Trial. Call me if you want more info or details on this trial.
