GA3与CPPU对葡萄果锈相关物质合成及基因表达的影响

摘要

为探究葡萄的防锈措施,本研究以阳光玫瑰葡萄为试验材料,于花后14 d,用25 mg/L的GA3分别和0 mg/L、5 mg/L、10 mg/L、15 mg/L的CPPU组合处理果穗,以清水处理为对照(CK).待果实进入转色期后分别采集不同成熟阶段的葡萄果实,通过实时荧光定量PCR测定与果锈生成相关的苯丙氨酸解氨酶(PAL)基因和白藜芦醇合酶(RS)基因的表达水平,测定葡萄果皮果锈发生率、果皮中次生代谢物含量等指标.结果表明,果实成熟过程中,与对照相比,GA3+CPPU处理后,PAL和RS基因表达水平降低,PAL基因表达峰值、RS基因表达水平均与CPPU处理浓度呈负相关.与对照相比,GA3+CPPU处理显著降低了果皮中白藜芦醇、总酚和木质素含量,咖啡酸、香豆酸、丁香酸等酚酸含量随 CPPU浓度增加显著下降,儿茶素和没食子酸含量随 CPPU 处理浓度增大先升后降.GA3+CPPU处理的葡萄果皮果锈发生率明显降低.与GA3+5 mg/L CPPU处理的葡萄果实相比,GA3+10 mg/L CP-PU和GA3+15 mg/L CPPU处理的葡萄果实成熟期推迟,风味下降,商品性显著降低.因此,生产实践上用GA3+CPPU处理阳光玫瑰葡萄果穗的适宜质量浓度为25 mg/L GA3+5 mg/L CPPU.%In order to explore the russet prevention measures of grapes, table grape cultivar Shine Muscat was used as material. On the 14th day after anthesis, grape fruit clusters were treated with 25 mg/L GA3(Gibberellin A3)+0 mg/L CPPU(forchlorfenuron), 25 mg/L GA3+5 mg/L CPPU, 25 mg/L GA3+10 mg/L CPPU and 25 mg/L GA3+15 mg/L CP-PU, respectively, and treated with water as control(CK). After the fruit entered veraison, grape fruits in different stages of maturity were collected separately. The expression levels of phenylalanine ammonia lyase (PAL) gene related to the formation of fruit russet and resveratrol synthase (RS) gene were measured by real-time fluorescence quan-titative PCR. The fruit skin russet level and secondary me-tabolites content in grape peel were determined. The re-sults show that, compared with the control, the gene ex-pression level of PAL and RS after CPPU treatment were decreased during the process of fruit ripening. The expression peak value of PAL gene and the expression level of RS gene negatively correlated with the concentration of CPPU treatment. To compared with those in control, the contents of total phenol, resveratrol and lignin in pericarp of berries were significantly decreased in the treatment of GA3 and CPPU. With the increase of CPPU concentration, the content of phenolic acids such as caffeic acid, fenugreek acid and clove acid decreased significantly however, the content of catechin and gallic acid in-creased first and then decreased. The incidence of berry russet was reduced significantly under the treatment of GA3 and CPPU. Compared with that of the grape berries treated with GA3 and 5 mg/L CPPU, the maturity of the grape berries trea-ted with GA3 and 10 mg/L CPPU or 15 mg/L CPPU was delayed, the flavor was decreased and the marketability was de-creased significantly. Therefore, the optimum treatment was 25 mg/L GA3 combined with 5 mg/L CPPU.