Preharvest spraying calcium ameliorated aroma weakening and kept higher aroma-related genes expression level in postharvest 'Nanguo' pears after long-term refrigerated storage

摘要

Refrigerated storage postponed the post-ripening of 'Nanguo' pears (Pyrusussuriensis Maxim.), but the aromatic esters of the pears were apt to weaken when the fruit was transferred to room temperature. CaCl2 treatment, in which the pears were sprayed with 4% CaCl2 during the days before harvest, inhibited the appearance of aromatic weakening of the postharvest pears after long-term refrigerated storage in the study. CaCl2-treated pears presented higher respiration rate, ethylene production and aliphatic acids during ripening in shelf life at room temperature. Higher genes expression of lipoxygenase (LOX), and hydroperoxide lyase (HPL), which were associated with LOX pathway, were found in the CaCl2-treated fruit during the ripening in shelf life. The expression levels of genes ACS, ACC, PuEIN4 and PuEIN2 were up-regulated, which were related to ethylene-related pathway. These results demonstrated that the aroma weakening of 'Nanguo' pears can be effectively inhibited by CaCl2 treatment and the potential inherent mechanisms are discussed.