Genetic and geochemical signatures to prevent frauds and counterfeit of high-quality asparagus and pistachio

•DNA fingerprint, 87Sr/86Sr ratio and geochemical profiling were applied for PDO signature.•Microsatellites were useful in varietal identification and discrimination.•87Sr/86Sr ratio of soil bioavailable Sr is useful to trace geographical origin.•Geochemical profiling improves the discrimination power of Sr isotopic signature.•Geochemical profiles were more homogeneous in soils than in plants.

A fingerprinting strategy based on genetic (simple sequence repeat) and geochemical (multielement and 87Sr/86Sr ratio) analysis was tested to prove the geographical origin of high-quality Italian products “White Asparagus from Bassano del Grappa” and “Green Pistachio from Bronte”. Genetic analysis generated many polymorphic alleles and different specific amplified fragments in both agriproducts. In addition, a core set of markers was defined. According to variability within production soils and products, potential candidate elements linking asparagus (Zn, P, Cr, Mg, B, K) and pistachio (Mn, P, Cr, Mg, Ti, B, K, Sc, S) to the production areas were identified. The Sr isotopic signature was an excellent marker when Italian asparagus was compared with literature data for Hungarian and Peruvian asparagus. This work reinforces the use of Sr isotope composition in the soil bioavailable fraction, as assessed by 1 mol/L NH4NO3, to distinguish white asparagus and pistachio originating from different geographical areas.