Among the different strategies to cope with the negative impacts of climate change on viticulture, the exploitation of genetic diversity is one of the most promising to adapt to new conditions and maintain wine production and quality. One of the biggest concerns in the context of climate change is to improve water use efficiency (WUE). In this way, the use of genotypes that present a better response to drought and high WUE is a key issue. In this work, physiological performance analysis was conducted to compare the water deficit stress (WDS) responses of local and widespread grapevines cultivars. Leaf gas exchange, water use efficiency (WUE) at different levels (leaf and long-term WUE (∆13C)), leaf osmotic adjustment and other water relations parameters were determined in plants under well-watered and WDS conditions alongside assessment of the levels of foliar hormones concentrations. Results denote that local cultivars displayed better physiological performance under WDS as compared to the widely-distributed ones. he results corroborate the hypothesis that better stomatal control allows increasing leaf WUE under drought as occurred in the local Callet cv.; but the minority local cultivar Escursac cv. showed high WUE under both treatments. In this case, high WUE can be related to maintaining higher photosynthetic activity under drought. The different mechanisms underlying the better performance under WDS and high WUE of minority local cultivars are discussed.
Authors: Josefina Bota1, Elena Baraza1, Miquel Capó1, Josep Cifre1, Maria Jose Clemente1, Enrico Cretazzo2, Miquel Llompart1, and Miquel Ribas-Carbó1
1Grup de Recerca en Biologia de les Plantes en Condicions Mediterranies, INAGEA, Departament de Biologia, Universitat de les Illes Balears, Palma de Mallorca, Spain
2 Instituto Andaluz de Investigación y Formación Agraria, Pesquera, Alimentaria y de la Producción Ecológica (IFAPA), centro Rancho de la Merced, Jerez de la Frontera, Spain
Keywords: water deficit stress, genetic variability, local cultivars, water use efficiency, Vitis vinifera