title: Effect of irrigation regime on anthocyanin content and antioxidant activity of Vitis vinifera L. cv. Syrah grapes under semiarid conditions.
abstract: BACKGROUND
  Irrigation management is a powerful technique to control grape and wine colour. However, water deficit effects on anthocyanins are often contrasting, depending on the severity of water restriction. In addition, the effect of irrigation on the antiradical capacity of grapes has not been extensively studied. In this work the effect of water availability on anthocyanin profile and content as well as the antioxidant activity of Syrah grapes was investigated in an irrigation trial under semiarid climate conditions.
  
  
  RESULTS
  Three irrigation treatments were applied in a 15-year-old Vitis vinifera cv. Syrah vineyard, starting at berry set through harvest of 2011 and 2012: full irrigation (FI) at 100% of crop evapotranspiration (ETc), deficit irrigation (DI) at 50% of ETc and non-irrigated (NI). NI grapes were characterized by increased individual anthocyanin content. However, differences among irrigation treatments were significant only around 18-24 days after veraison, when anthocyanin accumulation was maximum. The antioxidant activity of the skin extracts was not affected by irrigation.
  
  
  CONCLUSIONS
  Irrigation proved to be an effective technique to control anthocyanin content in Syrah grapes under semiarid conditions. However, anthocyanin accumulation pattern should be considered by winemakers to appropriately select harvest time for improved wine colour.
authors.affiliation: Department of Food Science and Human Nutrition, Agricultural University of Athens, GR-11855 Athens, Greece.
authors.forename: Maria
authors.initials: M
authors.lastname: Kyraleou
authors.affiliation: Laboratory of Viticulture, School of Agriculture, Aristotle University of Thessaloniki, GR-54124 Thessaloniki, Greece.
authors.forename: Stefanos
authors.initials: S
authors.lastname: Koundouras
authors.affiliation: Department of Food Science and Human Nutrition, Agricultural University of Athens, GR-11855 Athens, Greece.
authors.forename: Stamatina
authors.initials: S
authors.lastname: Kallithraka
authors.affiliation: Laboratory of Viticulture, School of Agriculture, Aristotle University of Thessaloniki, GR-54124 Thessaloniki, Greece.
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Theodorou
authors.affiliation: Department of Food Science and Human Nutrition, Agricultural University of Athens, GR-11855 Athens, Greece.
authors.forename: Niki
authors.initials: N
authors.lastname: Proxenia
authors.affiliation: Department of Food Science and Human Nutrition, Agricultural University of Athens, GR-11855 Athens, Greece.
authors.forename: Yorgos
authors.initials: Y
authors.lastname: Kotseridis
mesh_terms: D057914:Agricultural Irrigation; D000872:Anthocyanins / Q000737:chemistry*; D000975:Antioxidants / Q000737:chemistry*; D003889:Desert Climate; D006115:Greece; D006801:Humans; D027843:Vitis / Q000737:chemistry*; D014920:Wine
chemical_list: D000872:Anthocyanins; D000975:Antioxidants
keywords: Syrah; anthocyanins; antioxidant activity; grapevine; irrigation