关键词: 桃, 乙烯, 生物合成途径, 软化, 基因表达

Abstract:

To study the expression difference of genes involved in fruit softening and ethylene biosynthetic pathways under different temperature storage，different peach cultivars of‘Xiacui’and‘Yumyeong’with stonyhard，‘Yinhualu’with soft-melting，‘Hujing Milu’with hard-melting，and‘Babygold 6’with non-melting in 8 tenth maturity were collected as test materials. The results showed that only a little ethylene production were detected after harvest with fruits of‘Yumyeong’and‘Xiacui’，under either room temperature（25 ℃）or low temperature（4 ℃）. The fruit firmness of stonyhard cultivars retain at high level under room temperature with time going on，whereas low temperature induced‘Yumyeong’fruit to soften. Real-time quantitative PCR results indicated that PpACS1 gene was highly expressed in soft-melting，hard-melting and non-melting cultivars，but extremely low in stonyhard peaches. However，PpACS2 or PpACS3 could not be detected in all five cultivars. Moreover，cold treatment induced the expression level of PpACO1 gene in‘Xiacui’and‘Yumyeong’peaches，and significantly enhanced endo-PG expression in‘Yumyeong’peaches. In conclusion，this study revealed that fruit softening of peaches with different flesh textures were closely related to ethylene biosynthesis during the storage period，which were controlled via regulating relevant gene expression levels under different storage temperatures.

Key words: Prunus persica, ethylene, biosynthetic pathway, soften, gene expression