Abstract
The 87 Sr/ 86 Sr ratio is an effective geographical tracer for horticultural products. In plants this ratio reflects closely the characteristics of the growing area. However, information about the variability of this parameter when measured in different plant species or cultivars is still scarce. In this work, we have tested the hypothesis that, when plants are growing in the same environment, their 87 Sr/ 86 Sr ratio is independent from the plant species or cultivar. For this, four to six vegetable species were collected from two fields in different locations in South Tyrol (Italy), together with the corresponding soils. Additionally, within a single apple orchard located in the same area, apple leaves were collected from trees of five cultivars. The 87 Sr/ 86 Sr ratio was measured applying an established and validated method. In general, vegetable species growing in the same field had similar 87 Sr/ 86 Sr ratios and showed a lower variability compared to their corresponding soils, while a significant difference was found comparing the 87 Sr/ 86 Sr ratios of the two vegetable fields. Apple leaves sampled from different tree cultivars also did not show a significant difference in their 87 Sr/ 86 Sr ratio. We concluded that the 87 Sr/ 86 Sr ratio in vegetables and apple trees was affected by the soil, but not significantly by the type of species or cultivar. Therefore, within limited areas, the results of the 87 Sr/ 86 Sr ratio analysis based on samples of a certain species/cultivar can be extended to other similar plants growing in the same site.