Drought responses of grapevine cultivars under different environments
Using grapevine genetic diversity is one of the strategies to adapt viticulture to climate change. In this sense, assessing the plasticity of cultivars in their responses to environmental conditions is essential. For this purpose, the drought tolerance of Grenache, Tempranillo and Semillon cultivars grafted onto SO4 was evaluated at two experimental vineyards, one located in Valencia (Spain) and the other in Bordeaux (France). This was done by assessing gas exchange parameters, water relations and leaf hydraulic traits at the end of the season. On the one hand, inter-cultivar differences in those traits were confirmed, besides being fairly consistent between environments. On the other hand, for similar pre-dawn water potential among cultivars and environments, midday water potentials and gas exchange rates were lower in Valencia than in Bordeaux. This seems to be related to the higher vapor pressure deficit values in the former, even though leaf turgor loss point was 1 MPa lower in Valencia leaves than in Bordeaux. The leaves of the cultivars from the vineyard in Valencia showed a lower stomatal density and higher modulus of elasticity than their counterparts in Bordeaux. Moreover, both, leaf gas exchange rates and carbon isotope discrimination in grapes revealed that water use efficiency was higher in Valencia than in Bordeaux. Overall, differences among cultivars were milder than across environments, highlighting the high phenotypic plasticity of grapevine cultivars. This points to the importance of plant acclimatization processes in their responses to drought.
Issue: ICGWS 2023
1 EGFV, Bordeaux Sciences Agro, INRAE, Université de Bordeaux, ISVV, F-33882, Bordeaux (France).
2 Grupo de investigación de Biología de las Plantas en Condiciones Mediterráneas-Universidad de las Islas Baleares (PlantMed-UIB), Cra. de Valldemossa, km 7.5, 07122, Palma (Spain).
3 Instituto Valenciano de Investigaciones Agrarias, Centro para el Desarrollo Agricultura Sostenible, 46113, Moncada, Valencia (Spain).
4 Instituto Tecnológico de Viticultura y Enología, Servicio de Producción Ecológica, Innovación y Tecnología, Requena, Valencia (Spain).
5 CSIC, Departamento de Ecología y Cambio Global, Centro de Investigación sobre Desertificación (CSIC-UV-GV), Carretera CV‑315, km 10.7, 46113, Moncada, Valencia (Spain).