RT Journal Article SR Electronic T1 Changes in Sugar, Anthocyanin and ABA Accumulation in Response to Cluster Thinning and Girdling in ‘Jumeigui’ Grape JF American Journal of Enology and Viticulture JO Am J Enol Vitic. FD American Society for Enology and Viticulture SP ajev.2022.22038 DO 10.5344/ajev.2022.22038 A1 Xiaojun Xi A1 Qian Zha A1 Xiangjing Yin A1 Aili Jiang YR 2022 UL http://www.ajevonline.org/content/early/2022/09/23/ajev.2022.22038.abstract AB To overcome unsatisfactory appearance and flavor in grape berries, both cluster thinning and girdling are the practices widely applied in southern China. However, the changes in sugar, anthocyanin and ABA accumulation under cluster thinning and girdling, as well as the interactive effects of these two practices were poorly understood. In present study, four treatments (control, girdling, cluster thinning, and cluster thinning + girdling) were conducted prior to veraison in ‘Jumeigui’ table grapes across two consecutive seasons. It was shown that cluster thinning significantly increased sugar and anthocyanin concentrations, whereas girdling had no positive impact on these parameters at maturity. Both cluster thinning and girdling upregulated the transcript abundance of several corresponding genes involved in sugar accumulation and anthocyanin biosynthesis. The low LA/yield proportion under girdling against that under cluster thinning might result in low sugar and anthocyanin contents even though the transcript abundance of corresponding genes was upregulated. Furthermore, cluster thinning accelerated berry ABA biosynthesis, which was strongly correlated with the transcript abundance of NCED1 and NCED2, but girdling did not. The acceleration of ABA biosynthesis in ‘Jumeigui’ berries under cluster thinning might stimulate early sugar accumulation and anthocyanin biosynthesis, and then lead to higher sugar and anthocyanin contents than that seen with girdling.