Trellis systems are selected in wine grape vineyards to mainly maximize vineyard yield and maintain berry quality. This study was conducted in 2020 and 2021 to evaluate six commonly utilized trellis systems including a vertical shoot positioning (VSP), two relaxed VSPs (VSP60 and VSP80), a single high wire (SH), a high quadrilateral (HQ), and a guyot (GY), combined with three levels of irrigation regimes based on different crop evapotranspiration (ETc) replacements, including a 25% ETc, 50% ETc, and 100% ETc. The results indicated SH yielded the most fruits and accumulated the most total soluble solids (TSS) at harvest in 2020, however, it showed the lowest TSS in the second season. In 2020, SH and HQ showed higher concentrations in most of the anthocyanin derivatives compared to the VSPs. Similar comparisons were noticed in 2021 as well. SH and HQ also accumulated more flavonols in both years compared to other trellis systems. Overall, this study provides information on the efficacy of trellis systems on grapevine yield and berry flavonoid accumulation in a currently warming climate.
Authors: Justin D. Tanner1, Runze Yu1,2, Nazareth Torres1,3, Sean M. Kacur1,4, Lauren E. Marigliano1, Maria Zumkeller1, Joseph Chris Gilmer1, Gregory A. Gambetta4, Sahap Kaan Kurtural1,*
1Department of Viticulture and Enology, University of California, Davis, 1 Shield Avenue, Davis, CA, 95616, USA
2Formal post-doctoral scholar. Current address: Department of Viticulture and Enology, California State University, Fresno, 2360 E. Barstow Avenue, 2360 E. Barstow Ave. M/S VR 89, Fresno, CA, 93740, USA
3Formal post-doctoral scholar. Current address: Advanced Fruit and Grape Growing Group, Public University of Navarra, 31006 Pamplona, Spain
4EGFV, Bordeaux Sciences Agro, INRAE, Université de Bordeaux, ISVV, Villenave d’Ornon, France
Keywords: anthocyanins, flavonols, trellis systems, water deficits, viticulture