title: Grapevine Plasticity in Response to an Altered Microclimate: Sauvignon Blanc Modulates Specific Metabolites in Response to Increased Berry Exposure.
abstract: In this study, the metabolic and physiological impacts of an altered microclimate on quality-associated primary and secondary metabolites in grape (Vitis vinifera) 'Sauvignon Blanc' berries was determined in a high-altitude vineyard. The leaf and lateral shoot removal in the bunch zones altered the microclimate by increasing the exposure of the berries. The physical parameters (berry diameter and weight), primary metabolites (sugars and organic acids), as well as bunch temperature and leaf water potential were predominantly not affected by the treatment. The increased exposure led to higher levels of specific carotenoids and volatile terpenoids in the exposed berries, with earlier berry stages reacting distinctly from the later developmental stages. Plastic/nonplastic metabolite responses could be further classified to identify metabolites that were developmentally controlled and/or responded to the treatment in a predictable fashion (assessed over two consecutive vintages). The study demonstrates that grapevine berries exhibit a degree of plasticity within their secondary metabolites and respond physiologically to the increased exposure by increasing metabolites with potential antioxidant activity. Taken together, the data provide evidence that the underlying physiological responses relate to the maintenance of stress pathways by modulating antioxidant molecules in the berries.
authors.affiliation: Institute for Wine Biotechnology, Department of Viticulture and Oenology, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa.
authors.forename: Philip R
authors.identifier: http://orcid.org/0000-0002-6488-4859
authors.initials: PR
authors.lastname: Young
authors.affiliation: Institute for Wine Biotechnology, Department of Viticulture and Oenology, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa.
authors.forename: Hans A
authors.identifier: http://orcid.org/0000-0002-6822-9157
authors.initials: HA
authors.lastname: Eyeghe-Bickong
authors.affiliation: Institute for Wine Biotechnology, Department of Viticulture and Oenology, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa.
authors.forename: Kari
authors.initials: K
authors.lastname: du Plessis
authors.affiliation: Institute for Wine Biotechnology, Department of Viticulture and Oenology, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa.
authors.forename: Erik
authors.identifier: http://orcid.org/0000-0001-6320-2492
authors.initials: E
authors.lastname: Alexandersson
authors.affiliation: Institute for Wine Biotechnology, Department of Viticulture and Oenology, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa.
authors.forename: Dan A
authors.initials: DA
authors.lastname: Jacobson
authors.affiliation: Institute for Wine Biotechnology, Department of Viticulture and Oenology, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa.
authors.forename: Zelmari
authors.identifier: http://orcid.org/0000-0003-2776-955X
authors.initials: Z
authors.lastname: Coetzee
authors.affiliation: Institute for Wine Biotechnology, Department of Viticulture and Oenology, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa.
authors.forename: Alain
authors.identifier: http://orcid.org/0000-0003-0376-9301
authors.initials: A
authors.lastname: Deloire
authors.affiliation: Institute for Wine Biotechnology, Department of Viticulture and Oenology, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa mav@sun.ac.za.
authors.forename: Melané A
authors.identifier: http://orcid.org/0000-0001-6656-9353
authors.initials: MA
authors.lastname: Vivier
mesh_terms: D050260:Carbohydrate Metabolism; D002338:Carotenoids / Q000378:metabolism; D002734:Chlorophyll / Q000378:metabolism; D005638:Fruit / Q000254:growth & development / Q000378:metabolism; D017343:Genes, Plant; D008293:Malates / Q000378:metabolism; D053858:Metabolic Networks and Pathways / Q000235:genetics; D008834:Microclimate; D008954:Models, Biological; D018515:Plant Leaves / Q000378:metabolism; D013644:Tartrates / Q000378:metabolism; D013729:Terpenes / Q000378:metabolism; D027843:Vitis / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D014920:Wine; D024341:Xanthophylls / Q000378:metabolism
chemical_list: D008293:Malates; D013644:Tartrates; D013729:Terpenes; D024341:Xanthophylls; D002734:Chlorophyll; D002338:Carotenoids; C030298:malic acid; C029768:tartaric acid