干旱区生态环境知识资源中心

Background and Aims: Improving water-use efficiency (WUE) is desirable for future grapevine growth and grape production, especially in Mediterranean areas where water is predicted to be limiting. Understanding the genetic variability in WUE is important to identify the most appropriate cultivars to be used in semi-arid areas. Most previous studies have focused at leaf-level WUE, while information on whole-plant level is scarce. This study explored the genetic variability of grapevine in whole-plant WUE (WUEWP) to determine whether several leaf WUE (WUEl) indicators are suitable as proxies of WUEWP. Methods and Results: Three similar experiments were performed to compare WUE in up to eight different grapevine cultivars under irrigation and water-stress treatments. Although WUEl and WUEWP varied with cultivar and treatment, WUEl was not a reliable parameter to predict WUEWP. Conclusions: Large variability in WUEWP between grapevine cultivars was observed, although this variability was not described by leaf-level indicators of WUE. Significance of the Study: This study showed that the large variability existing for WUEWP in different cultivars offers an potential method for selecting the more suitable cultivars to grow in water-scarce viticulture areas, although WUEl is not reliable for estimating WUEWP.