Abstract: In order to explore the contents and distribution of metal elements in buckwheat, the contents of nine metal elements (Fe, Mn, Zn, Cu, Ca, Mg, Mo, Cd and Se) were determined by atomic absorption spectrometry, and the distribution of these metal elements was analyzed by principal component analysis and cluster analysis. Four principal factors accounted for 73.64% of total variances. The cumulative contribution rate of the first factor and the second factor to total variances was 44.41%, which suggested that copper, magnesium, molybdenum and cadmium were the characteristic elements in buckwheat. Cluster analysis showed that twenty-eight buckwheat samples could be classified as two groups, which could identify the genuineness of Fagopyrum Mill to some extent. Therefore, buckwheat was a good dietary source of essential trace metals for humans as well as trace metals such as Mg and Mo. The results of cluster analysis based on the contents of metal elements in buckwheat also can provide a reference for the classification of buckwheat species.

Key words: buckwheat, metal element, principal component analysis, cluster analysis, dietary resource