氯吡苯脲浸泡处理延缓采后芒果成熟和软化的生理机制

Physiological Mechanisms by Which Forchlorfenuron Soaking Treatment Delays Postharvest Ripening and Softening of Mango Fruit

以采后‘贵妃’芒果为试材,使用10 mg/L氯吡苯脲(forchlorfenuron,CPPU)溶液对果实浸泡处理10 min,晾干后在室温(25℃)条件下贮藏8 d,研究CPPU浸泡处理对芒果果实贮藏期间成熟与软化相关生理指标的影响。结果显示:CPPU浸泡处理明显抑制了芒果果实的呼吸作用并推迟了果肉色泽、硬度、可溶性固形物质量分数和可滴定酸质量分数的变化;CPPU浸泡处理有效抑制了果实1-氨基环丙烷-1-羧酸合成酶和1-氨基环丙烷-1-羧酸氧化酶活性,导致乙烯释放量降低;此外,CPPU浸泡处理显著抑制了果实多聚半乳糖醛酸酶、果胶甲酯酶、β-半乳糖苷酶等果胶水解酶活性变化,并较大程度抑制了果胶多糖的增溶与解聚作用,故而延缓了果实的软化进程。结论:CPPU浸泡处理能有效延缓采后芒果果实的成熟与软化,从而延长果实货架寿命。

Freshly harvested‘Guifei’mango fruit were dipped in 10 mg/L forchlorfenuron(CPPU)solution for 10 min and then taken out.After natural drying,the fruit were stored at room temperature(25℃)for 8 days to investigate the effect of CPPU on physiological indices related to fruit ripening and softening during storage.The results showed that CPPU strongly inhibited the respiration rate of mango fruit and delayed the changes in pulp color,firmness,soluble solids content(SSC),and titratable acids content(TAC).The activities of 1-aminocyclopropane-1-carboxylic acid(ACC)synthase(ACS)and ACC oxidase(ACO)were suppressed by CPPU treatment,which contributed to inhibiting ethylene production.In addition,CPPU markedly inhibited the activities of polygalacturonase(PG),pectin methylesterase(PME)andβ-galactosidase(β-Gal)to delay the solubilization and depolymerization of pectic polysaccharides,thus slowing down the softening process of mango fruit during storage.Accordingly,we concluded that that CPPU could delay fruit ripening and prolong the shelf life of postharvest mangoes.