Use applications of Diazinon granules. Sweet Potato Diseases Black Rot Black, sunken, roundish spots form. Black cankers form on the underground parts of stems and the disease often spreads in storage. No chemical control is listed.
Plants are yellow and wilted.
Stem cross sections show black discoloration and roots have a black ring when cut open. No chemical control is listed. This information is for educational purposes only. References to commercial products or trade names does not imply endorsement by MSU Extension or bias against those not mentioned. This information becomes public property upon publication and may be printed verbatim with credit to MSU Extension.