Canopy Architecture and Sun Exposure Influence Berry Cluster–Water Relations in the Grapevine Variety Muscat of Alexandria
Olfa Zarrouk,
Clara Pinto,
Maria Victoria Alarcón,
Alicia Flores-Roco,
Leonardo Santos,
Teresa S. David,
Sara Amancio,
Carlos M. Lopes,
Luisa C. Carvalho
Affiliations
Olfa Zarrouk
LEAF—Linking Landscape, Environment, Agriculture and Food Research Center, Associate Laboratory TERRA, School of Agriculture, University of Lisbon, Tapada da Ajuda, 1349-017 Lisboa, Portugal
Clara Pinto
INIAV—Instituto Nacional de Investigação Agrária e Veterinária, I.P. Avenida da República, Quinta do Marquês, 2780-159 Oeiras, Portugal
Maria Victoria Alarcón
Area of Agronomy of Woody and Horticultural Crops, Centro de Investigaciones Científicas y Tecnológicas de Extremadura (CICYTEX), 06187 Badajoz, Spain
Alicia Flores-Roco
Area of Agronomy of Woody and Horticultural Crops, Centro de Investigaciones Científicas y Tecnológicas de Extremadura (CICYTEX), 06187 Badajoz, Spain
Leonardo Santos
LEAF—Linking Landscape, Environment, Agriculture and Food Research Center, Associate Laboratory TERRA, School of Agriculture, University of Lisbon, Tapada da Ajuda, 1349-017 Lisboa, Portugal
Teresa S. David
INIAV—Instituto Nacional de Investigação Agrária e Veterinária, I.P. Avenida da República, Quinta do Marquês, 2780-159 Oeiras, Portugal
Sara Amancio
LEAF—Linking Landscape, Environment, Agriculture and Food Research Center, Associate Laboratory TERRA, School of Agriculture, University of Lisbon, Tapada da Ajuda, 1349-017 Lisboa, Portugal
Carlos M. Lopes
LEAF—Linking Landscape, Environment, Agriculture and Food Research Center, Associate Laboratory TERRA, School of Agriculture, University of Lisbon, Tapada da Ajuda, 1349-017 Lisboa, Portugal
Luisa C. Carvalho
LEAF—Linking Landscape, Environment, Agriculture and Food Research Center, Associate Laboratory TERRA, School of Agriculture, University of Lisbon, Tapada da Ajuda, 1349-017 Lisboa, Portugal
Climate-change-related increases in the frequency and intensity of heatwaves affect viticulture, leading to losses in yield and grape quality. We assessed whether canopy-architecture manipulation mitigates the effects of summer stress in a Mediterranean vineyard. The Vitis vinifera L variety Muscat of Alexandria plants were monitored during 2019–2020. Two canopy shoot-positioning treatments were applied: vertical shoot positioning (VSP) and modulated shoot positioning (MSP). In MSP, the west-side upper foliage was released to promote partial shoot leaning, shading the clusters. Clusters were sampled at pea size (PS), veraison (VER), and full maturation (FM). Measurements included rachis anatomy and hydraulic conductance (Kh) and aquaporins (AQP) and stress-related genes expression in cluster tissues. The results show significant seasonal and interannual differences in Kh and vascular anatomy. At VER, the Kh of the rachis and rachis+pedicel and the xylem diameter decreased but were unaffected by treatments. The phloem–xylem ratio was either increased (2019) or reduced (2020) in MSP compared to VSP. Most AQPs were down-regulated at FM in pedicels and up-regulated at VER in pulp. A potential maturation shift in MSP was observed and confirmed by the up-regulation of several stress-related genes in all tissues. The study pinpoints the role of canopy architecture in berry–water relations and stress response during ripening.
