Interelement correlations detectable in plant samples based on data from reference materials and highly accurate research samples

Summary

A correlation analysis of 45 elements from various plant standard reference materials provided a number of highly correlated element pairs (r≤0.9) leading to the expectation of an interelement interaction. For the elements Fe³⁺, Al³⁺, Sc³⁺ and the lanthanides, these high correlations may be attributed to the similar ionic radius of the hydrated ions or the same charge. The highly correlated occurrence of some macroelements such as P and N reflects the close association of the two elements, particularly during protein biosynthesis. Of the alkali metals, K, and the alkaline earth metals Ca, Mg and, to some extent, also Sr display high correlations amongst themselves and with the macronutrients N and P. In correlating the transition elements with each other and with the micro- and macroelements, it was only possible to find a few high correlation coefficients; only the two element pairs Co/Mo and Cr/Co display high correlation coefficients. One of the reasons for this is probably the inaccuracy of the data material. It was not possible to confirm the highly negatively correlated element pairs reported in earlier work. It was not even possible to determine a clear negative trend for typical pairs of antagonists such as Al/Ca or Mn/Ca. The highest negative correlation was found for the B/Sb element pair at r=−0.75.