Dan Anco Clemson Peanut Notes No. 173 2026

(Updated: July 23, 2026, 2:33 p.m.)
Early phase of manganese deficiency

The following are comments from Dr. Dan Anco at Clemson:

Fungicides

With fungicide applications continuing to go out, several recent questions are included here.
Lucento has activity against both late leaf spot and white mold/stem rot; under typical pressure and application schedules, it has performed effectively so as not to require tank mixing with an additional active ingredient.
For fields where production history has been associated with increased white mold/stem rot infection pressure, how does tebuconazole perform? Work we conducted over multiple growing seasons has demonstrated tebuconazole to be a very economic product that contributes helpful control of white mold, but if local disease pressure is elevated, other options are capable of delivering a greater total amount of control per labeled application than teb is capable of providing; these include products like Excalia, Elatus, and Convoy/Umbra; Provost Silver contributes a helpful amount of control that was between that group and teb.
Elatus typically is compatible to be applied with manganese, but since there are many different nutrient products, a quick small-scale jar mix test can help confirm specific combinations with local water.
Ideally for late leaf spot disease control, our more robust preventative programs do not include extending application intervals to 3 or 4 weeks between sprays. This is based on multiple trials conducted under higher disease pressure and with common susceptible cultivars. We do sometimes face delays due to weather or other practical logistics, but if we are able to target intervals closer to two weeks, that helps move the prevention needle in our favor.

Late Season AMS Application

How late can we still apply AMS to help correct nitrogen deficiency? I do not have data looking specifically at this, but based on typical growth stages, I would think if we apply by 90 days after planting (R6), we should see benefit. Earlier application provides more time for the crop to make use of the N.

Mn

Peanut deficient with Mn green up after a supplemental foliar Mn application. When new growth is later produced, it is normal for the new growth to show deficiency symptoms again. If a second application is put out, I would still target the rate at the recommended 0.5 lb Mn. 

FarmForward Summit

Attached is an email with details for AgSouth's 2026 FarmForward Summit, a free one-day event in Charleston on July 31.


Dan Anco

Extension Peanut Specialist and Professor

Department of Plant and Environmental Sciences

Clemson University – Edisto Research and Education Center

64 Research Road

Blackville, SC 29817

630-207-4926 cell

danco@clemson.edu