Differences in Ethylene and Fruit Quality Attributes during Storage in New Apple Cultivars

Abstract

Physiological characteristics of five new apple cultivars from the Korean apple breeding program were evaluated as a function of harvest time and storage after harvest. Internal ethylene concentration (IEC), flesh firmness, soluble solids concentration (SSC), and titratable acidity (TA) were measured in 'Summer Dream', 'Summer King', 'Green Ball', 'Picnic', and 'Hwangok' apples at harvest, during shelf life at 20°C, and one day after cold storage at 0.5°C in air. IEC increased during shelf life in 'Summer Dream', 'Summer King', and 'Green Ball' but not in 'Picnic' or 'Hwangok', regardless of harvest time. Flesh firmness decreased towards harvest time and decreased gradually with time in cold storage only in the former three cultivars. In turn, IEC increased during cold storage in the first three cultivars but not for the last two cultivars, irrespective of harvest time. Changes in SSC and TA did not consistently relate to harvest time or storage period but TA tended to decrease as IEC increased. Furthermore, IEC was negatively correlated with flesh firmness except in the 'Green Ball' cultivar but the significance level was much greater in 'Summer Dream' and 'Summer King' (p < 0.0001) than in 'Picnic' (p < 0.01) or 'Hwangok' (p < 0.05) cultivars. Flesh firmness was positively correlated with TA in the first three cultivars but not in the last two cultivars. Overall, the results indicate that cultivars for which IEC increased after harvest had reduced flesh firmness and TA after storage.

Constant storage temperature delays firmness decreasing and pectin solubilization of apple during post‐harvest storage

“…Meanwhile, the firmness decreasing level of "Golden Delicious" was severe than that of "Fuji" apple during the entire storage period, which was consistent with the reports made by Win et al (2019) and Yoo et al (2016) that low ethylene production was linked to less reduction of firmness.…”

“…Red (positive) and blue (negative) correlations between analyses of respective values at *p < .05, **p < .01. The numbers in the boxes represented the correlation coefficients This was similar to observations made in other studies (Gwanpua et al, 2013;Johnston et al, 2001;Win et al, 2019;Yoo et al 2016) where ethylene had negative correlation with firmness. In addition, the ethylene production found in "Golden Delicious" was higher than that of "Fuji" apple.…”

“…The observation was taken at 3,000× magnification (bar = 1 μm). CW, cell wall; ML, middle lamella; PM, plasma membrane cultivars (Jung & Watkins, 2014;Win et al, 2019;Yoo et al, 2016).…”

Characterization of Fruit Quality Attributes and Cell Wall Metabolism in 1-Methylcyclopropene (1-MCP)-Treated ‘Summer King’ and ‘Green Ball’ Apples During Cold Storage

“…In addition, 1-MCP significantly suppressed the IEC in both cultivars, which is mainly involved in fruit ripening, but the IEC observed in ‘Summer King’ apples was higher than that of ‘Green Ball’ apples. This discrepancy could be due to the difference between the concentration of IEC induced by the two different cultivars (Jung and Watkins, 2014; Yoo et al, 2016). Yoo et al (2016) reported that low IEC is linked to less reduction of firmness, as observed in this study.…”

“…This discrepancy could be due to the difference between the concentration of IEC induced by the two different cultivars (Jung and Watkins, 2014; Yoo et al, 2016). Yoo et al (2016) reported that low IEC is linked to less reduction of firmness, as observed in this study.…”