Postharvest dormancy and sprout development in potato tubers stored with apple fruit

Abstract

The potato (Solanum tuberosum) is a highly valuable starchy crop, serving as an important staple food. However, the crop postharvest quality is compromised during storage due to sprouting, which normally leads to reduced shelf-life. Thus, the aim of the study was to assess the potential of apple fruit as a biological suppressant against sprouting of potatoes. Potato tubers were collected from four commercial farms, thereafter, stored alone (control) or with apple fruit at ambient temperature (23º C) for 30 days. Analysis of variance showed that storage duration influenced the efficacy of apple treatment on tuber sprouting and dormancy. Tubers stored with apple fruits had significantly (P<0.05) reduced mass loss after 30-day storage compared to the control which showed higher mass loss, while tubers stored with apple fruits had significantly reduced sprouting compared with the control. Generally, tuber sprouting, mass loss, decay, starch content, soluble sugars and dry matter accelerated with storage duration. Control tubers for Jamba had 100% sprouting compared to tubers stored with apple fruits, with Elmar obtaining minimum sprouting of 18%. Decay percentage did not differ significantly (P>0.05) between tubers stored alone or with apple fruit while reducing sugars significantly (P<0.05) increased with an increasing storage duration in untreated tubers as compared to apple treatment. Furthermore, apple treatment had a significantly (P<0.05) reduced dry matter and starch content compared to the control in all locations except for Elmar. The study demonstrated that storing potato tubers with apple fruit at ambient temperature can be a biological anti-suppressant in potato tubers. Therefore, the method could be adopted as an alternative to synthetic ethylene gas and various chemicals used to control potato tubers sprouting during postharvest storage.