Drought tolerance in grapevine (Vitis vinifera cv. Chardonnay) clones

Abstract

Viticulture’s global significance enhances the concerns arising from the impending climate changes, with recently studies emphasizing prolonged drought periods. In grapevine drought stress can negatively impact key physiological traits, affecting both yield and quality across major wine growing regions. A way of dealing with these issues lies on the spontaneous somatic mutations that give rise to intra-varietal diversity, a pool of genotypic, morphological and physiological diversity within a single variety. Three clones belonging to the Chardonnay variety were studied. The two-year-old graftings were grown in the greenhouse and transferred to the phenotyper room with controlled conditions where two treatments were applied: “control” with daily watering and “drought” with water deficit for 14 days plus a recovery period of four days. During the experiment, phenotypical measurements and sampling for isotopic analysis were done weekly.

The results from the experiment aim to reveal differences in grapevine clones’ tolerance to water deficit, highlighting variations in physiological responses and water use efficiency. Phenotypic changes, including reductions in plant height and leaf count, are seen among studied clones, with some showing faster post-drought recovery. Further results, from autonomous and continuous sources, regarding phenotypical traits are forthcoming. The study hopes to provide valuable insights into the role of intra-varietal diversity in grapevine drought resilience. The identification of clones with superior stress tolerance will be critical for developing sustainable viticultural practices in response to climate change; by leveraging natural genetic variability, the findings will aid the identification of materials and improve viticulture management.