甜樱桃果实软化研究进展

Research Progress of Sweet Cherry Fruit Softening

软化是果实充分成熟的标志,软化成熟的果实具有理想的色泽、风味,并积累大量的风味物质和营养物质。甜樱桃果实软化主要发生在转色期,果肉细胞迅速膨大,细胞壁开始溶解,胞间层消失,成熟期果实中细胞壁退化更为突出,细胞质的规则结构几乎完全消失。然而过度软化降低了果实对机械损伤和病原菌侵染的抵抗能力,严重缩短货架期,增加采后损失,甜樱桃果实成熟后软化已经逐渐成为产业问题。为解析甜樱桃果实软化的机制,提高果实品质,对甜樱桃果实成熟软化过程中细胞壁结构和组分变化、细胞壁降解相关酶[果胶甲酯酶(pectin methylesterase,PME)、纤维素酶(cellulase,CL)、多聚半乳糖醛酸酶(polygalacturonase,PG)、果胶裂解酶(pectate lyases,PL)、β-半乳糖苷酶(β-ga⁃lactosidase,β-Gal)和α-L-阿拉伯呋喃糖苷酶(α-L-Arabinofuranosidase,α-L-Af)]、细胞内碳水化合物代谢及激素[脱落酸(ABA)、乙烯(ETH)、生长素(IAA)和赤霉素(GAs)]和栽培环境(温度、矿质元素和栽培管理)对甜樱桃果实软化的影响等方面进行综述,并对甜樱桃果实软化在育种和分子方向的深入研究进行展望,为提高甜樱桃果实品质和贮藏性提供理论依据。

Softening is a sign that the fruit is fully ripe.The softened and ripe fruits have ideal color and flavor,and accumulate a lot of flavor substances and nutrients.Sweet cherry fruit softening mainly occur in the color transformation stage,accompanied by rapid expansion of flesh cells,initial dissolution of cell wall,and disappearance of intermediate lamella.In the ripening stage,cell wall degradation is more prominent,and the regular structure of cytoplasm almost disappeares.However,excessive softening reduces the resistance of fruit to mechanical damage and pathogen infection,seriously shortens shelf life,and increases postharvest loss.Softening of sweet cherry fruit after ripening has become an industry problem.In order to analyze the mechanism of sweet cherry fruit softening and improve the quality of sweet cherry fruit,we reviewed the effects of cell wall structure and component changes,cell contents and turgor pressure,enzymes[pectin methylesterase(PME),cellulase(CL),polygalacturonase(PG),pectate lyases(PL),β-galactosidase(β-Gal)andα-L-Arabinofuranosidase(α-L-Af)]and hormones(ABA,ETH,IAA,GAs)related to cell wall degradation,and cultivation environment(temperature,mineral elements,cultivation and management)on sweet cherry fruit softening.Subsequently,we prospected the further research on breeding and molecular aspects of sweet cherry fruit softening.This study can provide theoretical basis for improving the quality and storability of sweet cherry fruit.