Abstract: In order to explore the effects of exogenous gibberellic acid (GA3), thidiazuron (TDZ) and their combination with different concentrations on the astringency of ‘Jumeigui’ grape berry skin. Taking ‘Jumeigui’ grape as material，grape clusters were evenly dipped with GA3 (T1: 12.5 mg/kg GA3; T2: 25 mg/kg GA3; T3: 50 mg/kg GA3), TDZ (T4: 1.25 mg/kg TDZ; T5: 2.5 mg/kg TDZ; T6: 5 mg/kg TDZ) or their combination (T7: 25 mg/kg GA3+2.5 mg/kg TDZ) during the early stage of fruit physiological drop and the early stage of the fruit enlargement. Astringent substance content was analyzed regularly. The tannin distribution of fruit was observed by paraffin section. The results showed that tannin cells in the peel treated with different concentrations of GA3 or the combination were sparsely distributed. While tannin cells in the peel treated with different concentrations of TDZ were densely distributed, with more layers and deeper colors. The content of soluble tannin, insoluble tannin, total tannin, flavonoids, and total phenol of ‘Jumeigui’ grape fruit skin treated with different concentrations of GA3 or combination were less than that of control, and the anthocyanin content was higher than that of control. However, the content of soluble tannin, insoluble tannin, total tannin, flavonoids, total phenol and anthocyanin of ‘Jumeigui’ grape fruit skin treated with different concentrations of TDZ were all higher than that of control. The result of principal component synthetic evaluation showed that the order of the astringent taste compounds of eight treatments was T6＞T4＞T5＞CK＞T7＞T2＞T3＞T1. It showed that GA3 treatments had the best effect on reducing the astringency of grape peel, and the concentration of 12.5 mg/kg GA3 treatment was the best, followed by the mixed solution treatment. TDZ treatments were not conducive to reducing the astringency of grape peel. The above results provided a theoretical basis for improving the astringency of fresh grape berries by using plant growth regulators.

Key words: ‘Jumeigui’ grape, GA3, TDZ, astringency taste compound

摘要： 为研究赤霉酸（gibberellic acid，GA3）和噻苯隆（thidiazuron，TDZ）对葡萄果皮涩味的影响，以‘巨玫瑰’葡萄为试材，在果实生理落果初期和膨果初期分别用不同浓度的GA3（T1: 12.5 mg/kg GA3; T2: 25 mg/kg GA3; T3: 50 mg/kg GA3）和TDZ（T4: 1.25 mg/kg TDZ; T5: 2.5 mg/kg TDZ; T6: 5 mg/kg TDZ）及其混合液（T7: 25 mg/kg GA3+2.5 mg/kg TDZ）浸蘸果穗，定期检测葡萄果皮中涩味物质含量的变化，并通过石蜡切片观察果皮中单宁细胞的分布情况。结果表明：不同浓度GA3及混合液处理的单宁细胞分布较少，不同浓度TDZ处理的果皮中单宁细胞分布密集，且层数较多，颜色较深；果实成熟时GA3及混合液处理的果皮中可溶性单宁、不溶性单宁、单宁总量、类黄酮和总酚的含量均低于对照，花色苷含量均高于对照；而不同浓度的TDZ处理的果皮中可溶性单宁、不溶性单宁、单宁总量、类黄酮、总酚和花色苷含量均高于对照。综合评价不同处理的涩味物质总量，结果为T6＞T4＞T5＞CK＞T7＞T2＞T3＞T1。说明GA3处理降低葡萄果皮涩味的效果最好，且以12.5 mg/kg GA3处理的效果最佳，混合液处理次之，TDZ处理不利于果实涩味的降低。上述结果为利用植物生长调节剂改善鲜食葡萄果实涩味提供理论依据。

关键词: ‘巨玫瑰’葡萄, 赤霉酸, 噻苯隆, 涩味