本研究以茌梨(Pyrus bretschneideri Rehd. Cv. Chili)果实为材料，分析了内切-β-1,4-葡聚糖酶（EGase）基因PbEG3和PbEG4在果实发育及成熟衰老时期的表达模式。茌梨果实中PbEG3和PbEG4的基因表达量均于发育时期呈现峰值，其中，PbEG3的基因表达量在花后70 d达到峰值0.31，花后130 d降至0.003；而PbEG4的基因表达峰值于花后110 d出现，为0.14，花后130 d降为0.005，与EGase的活性变化趋势一致。0 ℃贮藏期间，茌梨果实中PbEG3和PbEG4的基因表达量均呈下降趋势，且二者均在采收点呈现最大值，其中PbEG3于采后60 d表达量最低，之后表达量略有升高；而PbEG4在贮藏期间的表达量均较低。采后乙酰水杨酸(ASA)处理能够减少茌梨果实的失重，抑制其可溶性果胶的增加，降低EGase活性，延缓纤维素的降解，从而推迟果实的成熟衰老进程。PbEG3和PbEG4可能与茌梨果实的生长发育有关，未参与其采后衰老进程。

The expression patterns of PbEG3 and PbEG4, which encode endo-β-1,4-glucanase (EGase), were analyzed during fruit development, maturation, and senescence of the chili pear (Pyrus bretschneideri Rehd. Cv. Chili). Both PbEG3 and PbEG4 showed the highest expression during the fruit development period. The highest levels of expression of PbEG3 and PbEG4 were found to be 0.31 and 0.14, at 70 d and 110 d after anthesis, respectively. At 130 d after anthesis, the expression levels of PbEG3 and PbEG4 decreased to 0.003 and 0.005, respectively. The expression pattern of PbEG4 was found to be consistent with the enzyme activity of EGase. During storage at 0 ℃, the expression of both PbEG3 and PbEG4 exhibited a decreasing trend, and was the highest on the day of harvest. PbEG3 expression was lowest at 60 d after harvest, and then increased slightly, while PbEG4 expression was consistently low during storage. Postharvest acetylsalicylic acid (ASA) treatment decreased fruit weight loss, inhibited the increase of soluble pectin content, reduced the activity of EGase, and delayed the degradation of cellulose, thereby delaying the processes of fruit ripening and senescence. These results indicated that PbEG3 and PbEG4 might be related to the growth and development of chili pear, but not the senescence process.

国家自然科学基金项目（31201608）；国家现代农业（梨）产业技术体系建设专项（nycytx-29-06）；山东省优秀中青年科学家科研奖励基金（BS2010NY009）；山东省高等学校科技计划项目（J09LC13）