The effect of pruning severity on quercetin and catechin content in berry skins of cv. Blaufränkisch (Vitis vinifera L.) was studied over 3 years. Different crop levels and canopy structures were obtained by retaining 8, 16, and 24 nodes per vine at pruning. | Research Article Turk J Agric For 34 (2010) 461-466 © TÜBİTAK doi: Pruning effect on content of quercetin and catechin in berry skins of cv. Blaufränkisch (Vitis vinifera L.) Zoran S. BESLIC1,*, Slavica R. TODIC2, Vele V. TESEVIC3, Milka B. JADRANIN4, Miroslav M. NOVAKOVIC5, Dejan TESIC6 1 Department of Viticulture, Faculty of Agriculture, University of Belgrade, Nemanjina 6, 11080 Zemun, SERBIA 2Department of Viticulture, Faculty of Agriculture, University of Belgrade, Nemanjina 6, 11080 Zemun, SERBIA 3University of Belgrade, Faculty of Chemistry, Studentski trg 12-16, 11000 Belgrade, SERBIA 4Institute of Chemistry, Technology and Metallurgy, Njegoseva 12, 11000 Belgrade, SERBIA 5Institute of Chemistry, Technology and Metallurgy, Njegoseva 12, 11000 Belgrade, SERBIA 6Charles Sturt University, Locked Bag 588, Wagga Wagga, 2678 NSW, AUSTRALIA Received: Abstract: The effect of pruning severity on quercetin and catechin content in berry skins of cv. Blaufränkisch (Vitis vinifera L.) was studied over 3 years. Different crop levels and canopy structures were obtained by retaining 8, 16, and 24 nodes per vine at pruning. Canopy density, which is proportionate to the shoot number per canopy volume, directly affects the intensity of photosynthetically active radiation (PAR). The quercetin content has been shown to be highly dependent on the light exposure of the berries in which it accumulates. An increase in node number linearly decreased skin catechin, and it is suggested that the decrease was caused by increased yield per vine. Key words: Bud load, canopy structure, berry skin, quercetin, catechin Introduction Phenolic compounds have an important effect on grape and wine sensory quality, as they provide the color, taste, and aroma (Morrison and Noble 1990; Mazza et al. 1999). They have an important function in wine stability during aging due to their preservative effect (Gomez-Plaza et al. 2001). Phenolic compounds also have an .
