Effects of strigolactone and abscisic acid on the quality and antioxidant activity of grapes (Vitis vinifera L.) and wines

This study employed various methods, including recording of phenological phenomena and analysis of physicochemical indicators, to scrutinize effects of strigolactone and abscisic acid on indicators of ripeness, phenolic compounds, and antioxidant activity. 50 μM GR24 (strigolactone analog), 200 μM ABA (abscisic acid), 50 μM GR24 + 200 μM ABA, and 200 μM ABA + 10 μM TIS108 (strigolactone-biosynthesis inhibitor) were employed in E-L34 and E-L35. Samples were collected from E-L34 to E-L38. Each treatment could improve sugar contents and reduce acid contents, especially in the ABA + TIS group whose contents were 1 °brix higher and 1.11 g/L lower than the control group. Additionally, the ABA and ABA + TIS groups could significantly contribute to phenolic accumulation, especially anthocyanins which were increased by at least 1.5 mg/g at each stage. However, the ABA + GR group had some inhibitory effects on ripening. Therefore, this study can lay a foundation for precisely applying exogenous ABA and GR24.