Changes in carbohydrate content in zucchini fruit (Cucurbita pepo L.) under low temperature stress.

Abstract

The postharvest handling of zucchini fruit includes low-temperature storage, making cold stress unavoidable. We have investigated the changes of soluble carbohydrates under this stress and its relation with weight loss and chilling injury in zucchini fruit during postharvest storage at 4 °C and 20 °C for up to 14 days. Two varieties with different degrees of chilling tolerance were compared: Natura, the more tolerant variety, and Sinatra, the variety that suffered more severe chilling-injury symptoms and weight loss. In both varieties, total soluble carbohydrates, reducing soluble carbohydrates and polyols content was generally higher during storage at 4 °C than at 20 °C, thus these parameters are related to the physiological response of zucchini fruit to cold stress. However, the raffinose content increased in Natura and Sinatra fruits during storage at 4 °C and 20 °C, although at 20 °C the increase in raffinose was more remarkable than at 4 °C in both varieties, so that the role of raffinose could be more likely related to dehydration than to chilling susceptibility of zucchini fruit. Glucose, fructose, pinitol, and acid invertase activity registered opposite trends in both varieties against chilling, increasing in Natura and decreasing in Sinatra. The increase in acid invertase activity in Natura fruit during cold storage could contribute in part to the increase of these reducing sugars, whose metabolism could be involved in the adaptation to postharvest cold storage.

• Authors: Francisco Palma, Fátima Carvajal, Carmen Lluch, Manuel Jamilena, Dolores Garrido
• Journal: Plant science : an international journal of experimental plant biology (Plant Sci) Vol. 217-218 Pg. 78-86 (Mar 2014) ISSN: 1873-2259 [Electronic] Ireland
• PMID: 24467899 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Chemical References

• Sugar Alcohols
• Glucosyltransferases
• sucrose synthase
• beta-Fructofuranosidase

Topics

• Adaptation, Physiological
• Carbohydrate Metabolism
• Cold Temperature
• Cucurbita (metabolism)
• Fruit (metabolism)
• Glucosyltransferases (metabolism)
• Stress, Physiological
• Sugar Alcohols (metabolism)
• beta-Fructofuranosidase (metabolism)