Distribution of selenium in different biochemical fractions and raw darkening degree of potato (Solanum tuberosum L.) tubers supplemented with selenate.

Effects of Se fertilization on potato processing quality, possible changes in Se concentration and form in tubers during storage, and retransfer of Se from seed tubers were examined. Potato plants were grown at five selenate (SeO4(2-)) concentrations. Tubers were harvested 16 weeks after planting and were stored at 3-4 degrees C prior to analysis. The results showed that the Se concentration did not decrease during storage for 1-12 months. In tubers, 49-65% of total Se was allocated in protein fraction, which is less than found in plant leaves in a previous study. The next-generation tubers produced by the Se-enriched seed tubers had increased Se concentrations, which evidenced the relocation of Se from the seed tubers. At low levels, Se improved the processing quality of potato tubers by diminishing and retarding their raw darkening. The value of Se-enriched potato tubers as a Se source in the human diet was discussed.