Nondestructive evaluation of quality changes and the optimum time for harvesting during jujube (Zizyphus jujuba Mill. cv. Changhong) fruits development.

摘要

Jujube fruit is an increasingly important fruit in the world for its high nutrients content and the harvest time is crucial for jujube fruit quality. The aim of the study was to evaluate the quality changes and the optimum time for harvesting of jujube fruit (Zizyphus jujuba Mill. cv. Changhong) by chlorophyll fluorescence. Our results showed that jujube fruit cv. Changhong displayed a double sigmoid growth curve with a very short lag phase. At the last three ripening stages (72, 80, and 88 days after petal fall), Fo, Fm, and Fv showed positive and significant correlation with DPPH radical scavenging activity, total phenolic, reducing sugar, ascorbic acid, and total flavonoid (0.729<=r<=0.920, P<0.05). However, pH, total soluble sugar and carotenoids showed negative and significant correlation with Fo, Fm, and Fv (-0.885<=r<=-0.826). The last three ripeness stages in our study were differentiated using the chlorophyll fluorescence parameters. Therefore, chlorophyll fluorescence is a helpful, nondestructive technique to evaluate the quality changes and the optimum time for harvesting of Changhong jujube.