Effects of Nitrogen Application on Selenium Uptake, Translocation and Distribution in Winter Wheat

Abstract

In order to better understand the effects of nitrogen application on accumulation, translocation and distribution of selenium in winter wheat and to provide theoretical reference for reasonable nitrogen application and increasing selenium content of grains. A pot experiment was carried out under greenhouse conditions with Se1 (0.74 mg·kg-1) or Se2 (2.60 mg·kg-1) levels of selenium, and each Se treatment was supplied with N1 (100 mg·kg-1) or N2 (200 mg·kg-1) levels of nitrogen, respectively. Selenium concentrations and biomass amounts of different parts of wheat were determined at jointing and maturity stage. The results showed that grain yield increased with increasing nitrogen levels by 13.2% and 24.0% in Se1 and Se2 treatment, respectively. Regardless of N rate, Se concentration of wheat increased with raising Se amended rate (P<0.01). Increasing nitrogen application could promote Se uptake of root and thus increase the selenium concentration of wheat grains and leaves, which was greater in Se1 treatment than in Se2 treatments. Se concentrations in wheat grain increased by 22.6% and 12.1% with the increasing N application rate in low and high Se treatment, respectively. The distribution ratios of Se in each organ ranked the same as BCFs, following the order of leaf > grain > glume > root. Increasing N fertilization increased the distribution ratio of Se in grains by 11.1% and 25.9% in low and high selenate treatments, respectively. High nitrogen fertilization could promote uptake and translocation of Se in wheat under low Se conditions, and improve Se use efficiency as well in the agricultural production.