Intercropping grapevine with rosemary: A promising alternative to conventional agriculture in the current frame of global change

The Mediterranean region is well known for its long history of viticulture and the use of herbs and spices in its cuisine. Given the increasing focus on intercropping as a sustainable agricultural approach to maximize land use efficiency or improve soil fertility amid global change, we conducted a study to assess the feasibility of intercropping grapevine (Vitis vinifera L. cv. Merlot) with rosemary (Salvia rosmarinus Spenn.) in a Mediterranean vineyard. The trial was established in a 22-year-old vineyard, where rows of rosemary plants were cultivated between grapevine rows one year prior to the evaluation. To test intercropping feasibility and the abiotic stress effects on the harvest of rosemary, two sampling dates were set to monitor grape maturation (veraison and harvest) and rosemary quality in terms of antioxidant contents and composition, so that both crops were simultaneously analyzed under typical Mediterranean conditions, using both physiological and quality parameters. Results showed that intercropping with young rosemary plants did not affect grapevine physiology state, and observed differences in the two samplings were due to environmental stress only, indicating a positive coexistence between these crops in the context of global change. Regarding grape quality, variations in total soluble sugars, titratable acidity, and phenolic compounds were influenced by ripening during the summer, but not by intercropping, thus maintaining fruit quality. Rosemary contained high levels of antioxidants and exhibited strong antioxidant activity, particularly during mid-August (coinciding with vintage), indicating its potential as a valuable source of natural antioxidants for dietary intake, including phenolic diterpenes, vitamin C, and vitamin E. In conclusion, intercropping grapevines with rosemary did not negatively impact plant physiological performance or grape quality, promoting the production of two high-quality products with significant added value in the food sector under current stressful Mediterranean climatic conditions.