Abstract
Finding supplementary treatments with high sprout suppression efficacy is necessary for maintaining optimum potato ( Solanum tuberosum L.) tuber quality in storage. The objective of this research was to determine the efficacy of sweet orange ( Citrus sinensis) , spearmint ( Mentha viridis) , and oregano ( Origanum vulgare ) essential oils (EOs) as sprout suppressor treatments and optimize their application methods. EOs were applied either thermally, using cv. Russet Burbank and cv. Ranger Russet tubers at different stages of dormancy, or applied via air-wicking method using mini tubers of cv. Russet Burbank. After the treatments, sprout growth of tubers was monitored and different tuber tissues were collected for biochemical analysis in the air-wicking study. Overall, thermal application of EOs was an effective method, and oregano EO exhibited higher efficacy for sprout control. When applied using an air-wick method, temporary sprout suppression until 6-weeks and lower reducing sugar content in bud tissues were observed with spearmint EO. Increase in chlorogenic acid content and activity of antioxidant enzyme was observed in primary bud tissues with oregano EO treatment, indicating a stress induction response. Overall, EO treatments impacted sugar metabolism, antioxidant enzymes, and secondary metabolites, which significantly influence the sprouting of potato tubers.