Storing Dudaim melon fruits (Cucumis melo var. dudaim) harvested at different stages of maturity

Authors: HATAMI, MOHSEN - University Of Tehran; KALANTARI, SLAMAK - University Of Tehran; SOLTANI, FOROUZANDEH - University Of Tehran; Beaulieu, John

Submitted to: HortTechnology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/19/2019
Publication Date: 5/20/2019
Citation: Hatami, M., Kalantari, S., Soltani, F., Beaulieu, J.C. 2019. Storing Dudaim melon fruits (Cucumis melo var. dudaim) harvested at different stages of maturity. HortTechnology. 29:3. https://doi.org/10.21273/HORTTECH04057-18.
DOI: https://doi.org/10.21273/HORTTECH04057-18

Interpretive Summary: Cucumis melo L. is one of the most important horticultural crops in Iran. One of the amazing groups of melon where less attention has been paid to C. melo var. dudaim, or Queen Anne’s Pocket melon, is also traditionally cultivated in Iran. We have demonstrated previously that the best apparent ripening indices for dudaim melons are the color change of stripes and tendril condition (yellow or dry tendril) and recommended internal ripening indices are color of fruit flesh and total soluble solids. However, there is often noted variability between and within Cucumis melon types regarding ethylene production, softening and postharvest chilling sensitivity. To the best of our knowledge, there are no publications elucidating the climacteric ethylene production in dudaim fruit. The goal of this work was to evaluate the storability, quality changes and generally postharvest behavior of different maturity stages of dudaim melon during storage. To investigate the postharvest behavior of the fruit, dudaim melons were planted and harvested at two maturity stages and harvested fruits were stored at two storage temperatures for three weeks. Various quality parameters including color, firmness, titratable acidity, pH, total soluble solids, weight loss, protein content, glucose, fructose, sucrose, maltose and ethylene production were examined during storage. The ethylene trend was an initial decrease after harvest and then increased ethylene production during storage at 13 °C. Increased ethylene production, in concert with color development at 13 °C, reaching similar qualities to ripe fruits, and the changing balance of measured mono and disaccharide sugars in the separated fruits from the plant likely indicates that ‘Zangi-Abad’ and ‘Kermanshah’ cultivars are climacteric. It was concluded that dudaim fruits can be harvested at an optimum stage of maturity, similar to known climacteric melon fruits, and then allowed to ripen at proper storage temperatures before consumption.

Technical Abstract: Dudaim (Cucumis melo Group Dudaim) is a unique member of the edible melon family (C. melo), of which few studies have been made of its postharvest physiology. In order to investigate the postharvest behavior of dudaim melon (‘Zangi-Abad’ and ‘Kermanshah’), they were planted, tagged at anthesis and harvested at two maturity stages including 21 and 28 d after anthesis (DAA). Harvested fruit were stored at 5 or 13 °C for up to 3 weeks and various quality parameters, including color, firmness, titratable acidity (TA), total soluble solids (TSS), weight loss, chilling injury, ethylene production, protein content, and glucose, fructose, sucrose and maltose, were assessed during storage. After 3 weeks of storage at 13 °C, early harvested fruit (21 DAA) had relatively similar color values (L*: lightness, a*: green–red tones, b*: blue–yellow tones) and TA compared with late-harvested fruit (28 DAA), but some quality traits, such as TSS, were not similar. Ethylene decreased initially after harvest and then started to increase during storage at 13 °C. In most treatments, glucose and fructose decreased while sucrose and maltose increased with advancing maturity. Increased ethylene production, in concert with color development at 13 °C, similar to ripe fruit, and the changing balance of measured mono and disaccharide sugars in harvested fruit likely indicates ‘Kermanshah’ is climacteric. Results for ‘Zangi-Abad’ were not as definitive. Dudaim fruit can be harvested at an optimum stage of maturity, similar to known climacteric melon fruit, and then allowed to ripen at proper storage temperatures before consumption. From the results of this study we recommend that harvest at 21 DAA and storage at a non-chilling temperature such as 13 °C are the optimal stage and temperature for long storage purposes.