Peanut planted near the end of April are near 110 to 120 DAP. Depending on cultivar maturity development and requirements in individual fields, the growing season is starting to draw to a close with harvest of earliest planted fields beginning in the coming weeks. Later plantings and longer maturing runners’ time will come later on.
For the last fungicide application, use of chlorothalonil/Bravo is still a good product to use either by itself or in a tank mix. Its broad spectrum helps to prevent new infections from increasing and, when in a tank mix, helps to buffer the mix partner from potentially insensitive LLS populations. Bravo is a protectant, so if there are subclinical infections where the lesions just haven’t yet become visible, we can still see an apparent increase in lesions after a spray. Still, near the end of the season the primary goals for LLS management are preventing defoliation to protect against yield loss and reducing lesion-load survival going into the next growing season.
If more “juice” is needed than a standard bravo, alto or topsin are two examples that can be added; there are other good combinations as well. A few questions have come up about bravo plus sulfur. I haven’t looked at that combination, but based on our data, I would recommend a sulfur and fungicide tank mix as a viable option near the end of the season. Our previous data has shown these combinations to be effective in situations where an individual fungicide may have less efficacy. We have more data looking at sulfur plus group 3 fungicides (provost or alto), with more limited but still encouraging data in combination with tebuconazole (also a group 3), or headline (group 11).
As we start pod blasting in the weeks leading up to target maturity, the general rules of thumb for percentage of pods in the orange + brown + black group are 70% for Virginias and 75 – 80% for runners. This can adjust depending on limiting field/vine conditions. Background information on pressure washer psi and turbo nozzles are included here https://www.clemson.edu/extension/agronomy/peanuts/docs/moneymaker/maturity.pdf