Crossing the border into the last week of May coming up, planting continues. The NASS report earlier this week listed the state as drought free, though some localized areas have had planting progress set back due to the rain. Warmer and likely drier conditions the week ahead should help with progress on further acres.
Aspergillus crown rot
Attached are a few pictures from the field including a couple seedlings killed by Aspergillus crown rot. The presence of black, sooty sporulation at or below the crown of the plant is a classic identifying sign of this disease. Seed quality and planting/growing conditions contribute the lion's share in influencing development of this disease. In addition to effective seed treatment, fluopyram (Velum) in-furrow can add further protection. While fluopyram is one of the active ingredients in Propulse, aspergillus crown rot is not on the label for Propulse.
Replanting
If standing water has partially drowned out an area of a field, I use a 2 plants/ft standing population as the threshold to whether or not (supplemental) replanting would be effective. Areas with less than 2 plants/ft we could consider dropping in a few inches next to the original furrow with additional seed. Most of the stands so far have looked good.
Thrips + Paraquat
For peanut planted a few weeks ago, thrips injury can start to become visible. This tends to reach its peak visible injury when the plants are about 30 days old. This overlaps with the time when paraquat/gramoxone can be applied (not greater than 28 days after cracking, ballpark 35 DAP). There can be a concern for paraquat-incited burn compounding thrips injury when the thrips injury is very severe. The presence of some thrips injury is not a cause for concern nor a sign of insecticide failure, and a good rule of thumb is whether or not the terminals have become necrotic as an indication of severe thrips injury, in which case a foliar application such as acephate would be helpful to help the plants recover before coming in with paraquat, provide the application window is viable. If black/necrotic terminals are not present, even if the leaves show wrinkling from thrips feeding, I would be comfortable with a paraquat application going out.
Peanut images 5-24-24 Dan Anco
Dan Anco
Extension Peanut Specialist and Associate Professor
Department of Plant and Environmental Sciences
Clemson University – Edisto Research and Education Center
64 Research Road
Blackville, SC 29817
630-207-4926 cell