Selenium uptake, translocation, subcellular distribution and speciation in winter wheat in responses to phosphorus application combined with three kinds of selenium fertilizer

Abstract

Background Selenium (Se) deficiency caused a series of health disorders in human beings, and Se concentration in the edible parts of crops can be improved by altering exogenous Se species. However, the uptake, transport, subcellular distribution and metabolism of selenite, selenate and SeMet influenced by phosphorus (P) has not been well characterized. Results The resulted showed that increasing P supply enhanced photosynthesis and then increase the dry matter weight of shoots at selenite and SeMet, and appropriate P combined with selenite increased the dry matter weight of roots by enhancing root growth. At selenite, increasing P supply significantly decreased the concentration and accumulation of Se in roots and shoots. P1 decreased the Se migration coefficient, which could be attributed to the inhibited distribution of Se in root cell wall but increased distribution of Se in root soluble fraction, as well as the promoted proportion of SeMet and MeSeCys in roots. At selenate, P0.1 and P1 significantly increased the Se concentration and distribution in shoots and Se migration coefficient, which could be attributed to the enhanced proportion of Se(IV) in roots but decreased proportion of SeMet in roots. At SeMet, increasing P supply significantly decreased Se concentration in shoots and roots, but increased the proportion of SeCys in roots. Conclusion Compared with selenite or SeMet, appropriate P combined with selenite could promote plant growth, reduce Se uptake, alter Se subcellular distribution and speciation, and then affect the Se bioavailability in wheat.