关键词: 马铃薯；矿质元素；稳定同位素

Abstract: In order to investigate the feasibility of identifying the geographical origin of potato based on mineral elements and stable isotopes, we determined the mineral element contents and stable isotope ratios of representative potato samples collected from five main potato-producing areas of China, Inner Mongolia, Heilongjiang, Xinjiang, Sichuan and Guangdong provinces. The results of principal component analysis (PCA), cluster analysis (CA) and discriminant analysis (DA) indicated that 8 fingerprint minerals, including sodium, aluminum, phosphorus, manganese, cobalt, nickel, copper and cadmium, were selected by stepwise method, and in the cross-validation, the correct discrimination rate was 89.3% for these minerals. δ13C and δ15N values could basically distinguish between samples from Inner Mongolia and those from Heilongjiang, Xinjiang and Guangdong. The discriminative accuracy of the model established based on δ13C and δ15N was 82.0%. Based on the fingerprint minerals combined with the stable isotopes, the initial correctness rate for the different geographical origins was 94.7%, and the correctness rate in cross-validation was 93.2%, both of which were higher than those obtained based on either of them alone, indicating good discrimination results. The results obtained in this study show that the combination of mineral elements and stable isotopes allows effective and accurate discrimination of the geographical origin of potato and therefore provides an effective method for geographical origin traceability.

Key words: potato; mineral element; stable isotope