外源油菜素内酯处理对‘美乐’葡萄果实糖代谢的影响

Effect of Exogenous Brassinolides Treatment on Sugar Metabolism of Merlot Grape Berries

以酿酒葡萄‘美乐’为试材,于花后8周对其果实喷施不同浓度(0.2、0.4、0.6 mg L^(-1))油菜素内酯(2,4-表油菜素内酯,EBR)溶液,以喷施等量蒸馏水为对照,研究EBR对果实成熟过程中糖组分、糖代谢关键酶及相关基因表达的影响。0.6 mg·L^(-1)EBR处理促进了果实发育过程中葡萄糖和果糖的积累,花后104 d分别较对照提高了16.95%和39.31%,果实成熟期酸性转化酶(AI)和蔗糖磷酸合成酶(SPS)活性均显著高于对照,果实转色至成熟过程中显著上调了细胞壁酸性转化酶基因(KvcwINV)、蔗糖转运蛋白基因(VvSUC12)、蔗糖合成酶基因(VvSS)的转录水平,花后67 d VvSS的表达量是对照的2.75倍。相关性分析表明,0.6 mg·L^(-1)EBR处理下果实中己糖含量与SS、AI活性呈显著正相关。0.6 mg·L^(-1)EBR处理提高了果实SS和AI的活性、促进了VvSS、VvcwINV以及VvSUC12的表达,从而增加了葡萄糖和果糖的含量。0.6 mg·L^(-1)EBR处理效果最好。

The purpose of this study was to explore the effect of exogenous brassinolides(2,4-Epibrassinolide,EBR)on sugar metabolism of Merlot grape berries.10-year-old grape Vitis vinifera‘Merlot’was used as the test material,and different concentrations of EBR(0.2,0.4,0.6 mg·L^(-1))solutions were sprayed in the eighth week after anthesis,with distilled water as the control.Using chemical analysis,HPLC,Enzyme-linked Immunosorbent assay,and transcription analysis to study the effects of EBR treatment on the sugar components,key sugar metabolism enzymes and related gene expression during the ripening process of‘Merlot’grapes.Compared with the control,0.6 mg·L^(-1)EBR treatment can significantly promote the accumulation of glucose and fructose in grape berries,the contents were respectively increased by 16.95%and 39.31%.At maturation,the activities of acid invertase(AI)and sucrose phosphate synthase(SPS)were significantly higher than the control.The 0.6 mg·L^(-1)EBR significantly up-regulated the transcription levels of cell wall acid invertase (Vvcw INV),sucrose transporter(Vv SUC12),and sucrose synthetase(Vv SS)during the process of grape color transformation to maturity.The expression of Vv SS gene was 2.75 times that of the control.Correlation analysis showed that hexose was significantly positively correlated with SS and AI under 0.6 mg·L^(-1)EBR treatment.0.6 mg·L^(-1)EBRtreatment improves the activity of SS and AI,and promotes the expression of Vv SS,Vvcw INV gene and sucrose transporter Vv SUC12 gene,thereby increasing the content of glucose and fructose.0.6 mg·L^(-1)EBR treatment has the best effect.