Submitted to: HortScience
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/30/2015
Publication Date: 2/5/2016
Citation: Lee, J., Mattheis, J.P., Rudell Jr, D.R. 2016. Storage temperature and 1-MCP treatment affect storage disorders and physiological attributes of ‘Royal Gala’ apples. HortScience. 51:84-93.
Interpretive Summary: Long term storage of apple fruit months after harvest allows fruit to be available over an extended time period. Factors other than edible quality can often limit apple fruit storage duration, particularly the development of browning in the flesh or peel. ‘Gala’ is a popular apple variety that is increasing in total production worldwide. Expanded production is due in part to relatively few postharvest disorders that result in browning. In recent years an increase in browning during storage has been observed, and factors influencing browning development have been examined to determine what if any part of the postharvest environment favors disorder development. Studies done at the Physiology and Pathology of Tree Fruits Research Unit identified a role for low storage temperature in disorder development that was modulated in part by inhibiting fruit ripening. The results show reducing browning related to low temperature may not be as simple as increasing storage temperature a few degrees.
Technical Abstract: ‘Royal Gala’ apples [Malus domestica (Borkh.) Mansf.] can develop postharvest disorders such as flesh browning, senescent breakdown, peeling, cracking, or shriveling during and after cold storage. The objective of this study was to examine the effects of storage temperature and a range of 1-methylcyclopropene (1-MCP) concentrations on fruit quality attributes and incidence and severity of physiological disorders during and after cold storage. Storage temperature significantly affected internal ethylene concentration (IEC), fruit circumference, and cortex color. 1-MCP treatment resulted in significant effects on fruit quality attributes and severity of physiological disorders, regardless of storage temperature. Incidence and severity of diffuse flesh breakdown, shriveling, cracking, and peeling were highest in control fruit stored but radial stem-end flesh breakdown only primarily in 1-MCP treated fruit. Incidence of radial stem-end flesh breakdown was highest following storage at 0.5 oC compared with 3 oC. 1-MCP treatment had the most influence on disorder incidence/severity or quality attributes, while treatment concentration of 1-MCP was not significant. Overall, the results indicate that 1-MCP treatment can reduce the incidence of ‘Royal Gala’ diffuse flesh breakdown but may enhance sensitivity to radial stem-end flesh breakdown, when fruit are stored at 0.5 oC or 3 oC. Incidence of diffuse flesh breakdown and radial stem-end flesh breakdown are influenced differentially by storage temperature or by 1-MCP treatment, respectively indicating they may be different disorders.