Sweetpotato Tip Rot Incidence Is Increased by Preharvest Applications of Ethephon and Reduced by Curing

• Published in: HortTechnology (Alexandria, Va.) Vol. 23; no. 3; pp. 288 - 293
• Main Authors: Arancibia, Ramón A., Main, Jeffrey L., Clark, Christopher A.
• Format: Journal Article
• Language: English
• Published: 01.06.2013
• ISSN: 1063-0198; 1943-7714
• DOI: 10.21273/HORTTECH.23.3.288

Tip rot, or restricted end rot, is a new sweetpotato ( Ipomoea batatas ) disease/disorder in Mississippi with unknown etiology. Since pathogen isolations have been inconsistent, a relationship of this disorder with stress is proposed. This disease/disorder is manifested as a restricted lesion at or close to the proximal end of the storage root and appears after 2 to 4 weeks in storage. In many cases, the lesion necrosis expands internally. On-farm and research station studies with preharvest foliar applications of ethephon were conducted in Mississippi to determine the potential association of tip rot with ethephon-induced stress. In addition, the effects of ethephon rate and interval between application and harvest on tip rot were investigated. After 1 to 2 months in storage, tip rot incidence was observed mostly in storage roots from ethephon-treated plants. The increase in tip rot incidence was well correlated with ethephon rate. These results suggest that preharvest applications of ethephon trigger a response that results in the tip rot disorder.