Dan Anco Comments Clemson Peanut Notes No. 143 2024

Aspergillus Crown Rot

The first picture is from a field where Aspergillus crown rot infection is resulting in individual plants becoming infected and necrotic. The black sooty sporulation by the base of the plant at the crown is characteristic but not always present. Extended hot and dry conditions are favorable for this disease. Reducing stress through irrigation, when available, is helpful. In fields where stands are good, this usually does not result in significant loss to yield. As plants grow, it likewise becomes less of an issue.


Leaf Cupping/Binding

The second picture is from a field where a peculiar cupping/binding showed up and could be found across the field (~60 acres). Leaves otherwise did not appear to show notable signs of infection or pest injury. In this particular field, standard products were applied without "enhancer" or "booster"-type products. Dr. Barry Tillman (UF) has seen similar symptoms develop when peanut was grown in a field that was previously planted to pasture, where aminopyralid was applied to the pasture before the land was prepared to plant peanut. In that case, there was more of a rolling appearance and less binding. As further questioning continued as to whether or not the sprayer used in this field was dedicated for peanut/row crops or also used for pasture, it turned out the sprayer used in this field was also used to apply Duracor (aminopyralid + florpyrauxifen-benzyl) to pasture. Sprayer contamination/inadequate cleanout thus was concluded as the most probable cause in the presence of the available evidence.


Zorial

The third picture was shared by Drake Perrow and is injury characteristic of Zorial contamination. In the field, it appeared to be in the area of a single tank load.


Late leaf spot

The forth picture is the top and bottom side of a late leaf spot lesion from a field planted to peanut many years in a row.


Growth Stage

The final picture is of a peanut at R3 growth stage. This is when pegs are growing into pods but the majority of which have not yet formed full sized pods.


As boron and manganese applications continue to go out, tank mixtures with increasing numbers of products will benefit from a quick small-scale jar test to make sure everything will mix and stay in solution without causing problems for the sprayer. Manganese tends to be the less compatible of the two, though checking can help to verify compatibility.


Peanut images 7-11-24

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

danco@clemson.edu