Dan Anco Clemson Diseases Peanut Notes No. 93 2021

— Written By
Disease Control
Dan Anco
Peanuts planted the last week of April are reaching 45 DAP this week. Fungicide programs for leaf spot should begin no later than 45 DAP and starting closer to 40 or 30 DAP can be warranted in fields with a history of challenging disease pressure, later plantings, volunteers nearby, and similar risk factors. If rains prevent timely sprays, the addition of a systemic product (Alto, Aproach Prima, Priaxor, Topsin) to the tank can help buffer a little lost time somewhat. If we can be timely, Bravo is still a great option early since the canopy penetration and coverage is that much easier when the plant is small.
If soil tests indicate a need (< 0.4 lb), the 45 DAP fungicide is usually a convenient time to get boron applied in a tank mix.
Around 45 DAP peanut are big enough to look at nodules on the taproot if canopies look yellow or we suspect inoculant did not go out in-furrow at planting. Like to see at least 15 nodules per taproot.
The usual time we think about for beginning white mold fungicide protection starts at 60 DAP. This can move up in years when we have a hotter early season. In 2019 we saw this in some fields. This year we have had some spells in the 90s already and may get more in areas in the days to come. Not all fields are “white mold fields”, but for those with known histories of white mold problems, consider including fungicides for white mold management in the 45-day spray. (Excalia, Elatus, Provost, Fontelis, Convoy, teb, and more listed in the production guide).