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Many higher plants are beneficial from silicon (Si) or/and selenium (Se) via root absorption pathway when grown on adversity conditions.However,the present researches on mechanisms of stress alleviation by foliar addition of Si or/and Se are still rarely reported.In this study,we examined the discrepant resistance mechanisms on absorption,compartmentation and translocation of cadmium (Cd) within a leaf vegetable cultivar named Brassica campestris L.ssp.chinensis var.utilis through foliar addition of Si or/and Se exposed to low-and-high Cd stress.The results showed that plant growth was significantly stimulated by foliar addition of Si or/and Se according to the increased plant tissue biomass at high-dose Cd exposure.Additionally,the total Cd accumulation in whole plants were greatly increased after the foliar addition of Si or/and Se when exposed to high Cd stress,this may be due to the elevated Cd accumulation in plant roots.Moreover,the foliar addition of Si alone or combined with Se markedly inhibited the Cd concentrations in plant shoots and the translocation ability of Cd from roots to shoots (TF) at both two dose Cd treatments,which might be explained as the lower Cd concentrations and its proportions in symplast and apoplast,the higher Cd concentrations in cell walls of plant roots,and the lower Cd concentrations in xylem,while no significant changes of these indexes were observed at the treatment of Se alone.As a whole,these findings demonstrate that the induced resistance to Cd by foliar Si addition may be responsible for inhibition of Cd absorption and its translocation to plant shoots,and reinforcing its compartmentation onto root cell walls,while other resistance mechanisms may be employed by foliar Se addition.