Electron microprobe and neutron activation analysis for the determination of elemental distribution in hollow heart potato tubers

Electron microprobe and neutron activation analysis were used to evaluate the distribution of elements within potato tubers having the physiological disorder hollow heart. Both methods of analysis correlated well for all elements tested. In hollow heart tubers, there were significantly higher Ca⁺⁺ levels in the stem end than in the bud end; however, a Ca⁺⁺ gradient in the control was not evident. The stem to bud end ratios for Ca⁺⁺ were highest in the hollow heart tubers. A Cl^- gradient from stem to bud end was obvious in both the hollow heart and control tubers. In the control tubers, K⁺ was highest in the bud end and lowest in the stem end. There was no K⁺ gradient in hollow heart tubers, but in the area adjacent to the hollow it was higher than at both ends.