Grapevine leaf ionome is shaped by soil factors and plant age

The concept of terroir relates the sensory attributes of wines attributable to the environmental conditions of the grapevines, and therefore it represents an important descriptor of the connection between wines and their origins. In ongoing efforts to improve the monitoring and geochemical fingerprinting of grapevine products, knowledge of the variability of grapevine elemental compositions, and factors that have strong influences on this, can significantly improve the traceability of wines to their origins. Here, we demonstrate a strong connection of grapevine elemental composition to the micro-location of the individual vineyard, with an important contribution from the biotic soil factors. The differences in measured leaf elements appear to be more closely connected to the grapevine age than to the viticultural practice (biological vs. conventional). Soil microbial communities have a substantial impact on grapevine leaf elements, with differences seen between fungi and bacteria. Bacteria appear to be more closely related to the environment in vineyards than fungi, with changes in their interplay reflected in the elemental composition of the grapevines. Nevertheless, both microbial groups explain 15% to 17% of the variation in the grapevine leaf elements, making the soil fungal and bacterial communities critical factors in the terroir concept.