Effects of different concentrations of Se6+ on selenium absorption,transportation, and distribution of citrus seedlings (C. junos cv. Ziyang xiangcheng)

Different concentrations of selenium (Se⁶⁺) were added in order to detect the rules of Se absorption, transportation, and distribution in seedlings of Ziyang xiangcheng. After two months of treatments, seedling growth parameters, Se concentrations in different parts, and rhizosphere microbial counts were detected. We found 1–8 mg Se⁶⁺/L treatments promoted plant growth, especially at 2 mg/L. The seedling Se concentrations were also improved with the increase of Se dose. Both Se concentrations and total Se content were the largest in leaves, followed by roots and stems. The counts of bacteria and fungi were maximized at the dose of 2 mg Se⁶⁺/L. With the increase of Se dose, Se transaction factors were reduced. Moreover, bioconcentration factors (BCFs) viz BCF_root/soil and BCF_stem/soil were maximized at the dose of 2 mg/L Se⁶⁺. These results indicated that the optimized growth Se content is at the dose of 2 mg Se⁶⁺/L.