Study on the Relationship Between Peach Fruit Softening,Cell Wall Degradation Related Glycosidase and Ethlylene Biosynthesis

【Objective】Two peach(Prumus persica) cultivars were used as materials.β-galactosidase,α-L-arabinofuranosidase and ethylene biosynthesis related enzymes were determined for analyzing the relationship between them and peach fruit softening.【Method】Firstly,through gas chromatography approach,ethylene productions were determined.Then the relevant enzyme activities were determined using conventional physical and chemical analysis methods.And then a combination of semi quantitative reverse transcriptase-PCR(RT-PCR) and real-time PCR were allowed to analyse the expression of related genes in peach.【Result】 Softening characteristics were quite different between the two peach cultivars.The results showed that ethylene production increased significantly in 'Yuhua 3' accompanied by the decline of firmness,while relatively higher firmness had been remained during 'Jianayan' peach fruit ripening.Ethylene production in 'Jianayan' peach fruit was less than 1% of that in 'Yuhua 3' peach fruit.β-galactosidase gene expression and activity had a higher level in the early stage of softening.The gene expression and activity of α-L-arabinofuranosidase were higher in the late ripening and the change of α-L-arabinofuranosidase slightly lagged behind the rapid changes of ethylene and ethylene synthetic enzymes.【Conclusion】β-galactosidase may contribute to the initiation of peach fruit softening,while α-L-arabinofuranosidase activation was closely related to the accumulation of endogenous ethylene and had more remarkably effect on mid to later fast-softening during peach ripening.