Historical multi-environment analysis of chlorpropham sprout control programs for phytosanitary assurance in U.S. fresh, export potato markets
Rabecka Hendricks, Nora Olsen, Julia Piaskowski, Harpreet Kaur, Gustatavo Texeira, Albert Adjesiwor and Jeff Miller
American Journal of Potato Research
2026-10-19
2026
Abstract
Expanding export markets may rely upon the ability to minimize phytosanitary risks associated with exported fresh market potatoes by ensuring potatoes will not sprout and develop plants. This study analyzed two historical data sets to evaluate the effect of chlorpropham (CIPC) sprout inhibition (1) on sprout development during storage and (2) on plant emergence in the field. To assess storage temperature impact on sprout development, data from 2001 to 2010 storage seasons were compared between nontreated and thermal CIPC-treated potatoes using 25 varieties stored at three temperatures (5.6 C, 7.2 C, or 8.9 C). Sprout development was evaluated approximately one month after harvest and subsequently evaluated each month for approximately seven months. Field trials, conducted in 2009, 2010, 2012, 2014 and 2015, compared emergence of (1) nontreated tubers, (2) thermal CIPC-treated (22 mg \(L^{−1}\) application) tubers, (3) CIPC-spray treated tubers (various rates), and/or (4) a combination of both CIPC applications. After 150 days in storage, CIPC-treated tubers had a 1% probability of having a sprout greater than 5 mm in length compared to 41% probability of nontreated tubers. At 8.9 C, nontreated tubers rapidly developed sprouts compared to 5.6 and 7.2 C. When CIPC was applied, storage temperature had a minimal impact on sprout development and tubers remained at the peeping stage of sprout development for most of the storage duration. The probability of emergence from tubers treated with a combination of thermal and spray CIPC remained low (2%) up to 80 days after planting, compared to 98% probability of emergence from nontreated tubers. CIPC treatments significantly reduce sprout and plant development and are a critical tool as a sprout control agent and phytosanitary tool in the global trade of fresh market potatoes.