关键词: 桃, 着色, 反光膜, 色差, 色素, 基因表达

Abstract:

This study explored the effects of applying reflective film before harvest on fruit
appearance quality of peach（Prunus persica），and discussed the influencing mechanism on fruit coloration.
Yellow outside and black inside double-layer bags were removed from fruit 12 d before harvest. Peel
color，pigment content，enzyme activity as well as the gene expression related to fruit coloration of a
well-colored and late-ripening peach cultivar Xiahui 8 with different treatments（non-bagging with
non-reflective film mulching，debagging with non-reflective film mulching，debagging with reflective film
mulching）were researched. The results showed that both debagging with non-reflective film mulching and
debagging with reflective film mulching could significantly improve red and green color difference value（a*），a*/b*（b* is yellow and blue color difference value），chroma（C），anthocyanin（Ant）content and
reduce hue angle（h），while debagging with reflective film mulching had higher Ant content than
debagging with non-reflective film mulching（P < 0.05）. The two treatments up-regulated the transcript level
of anthocyanin biosynthetic related genes（UFGT，CHS）at the beginning of the experiment，however，
the expression of DFR，LDOX and F3H were enhanced along with the testing process. A downward trend
on phenylalanine ammonia lyase（PAL）activity of non-bagging with non-reflective film mulching was
observed during the experiment，however，the peel PAL activity of the other two treatments first increased
and then decreased. What’s more，peel PAL activity of debagging with reflective film mulching was higher
than debagging with non-reflective film mulching. These results suggested that Ant synthesis in the peel
was the result of cooperation among several genes，and debagging with reflective film mulching had better
effect on promoting Ant accumulation than debagging with non-reflective film mulching.

Key words: peach, coloration, reflective film, color difference, pigment, gene expression