Soil and foliar applications of silicon(Si)and selenium(Se)fertilizers can inhibit the transfer of heavy metals from the soil to crops.However,it remains unclear how Si and Se affect the bioavailability of cadmium(Cd)...Soil and foliar applications of silicon(Si)and selenium(Se)fertilizers can inhibit the transfer of heavy metals from the soil to crops.However,it remains unclear how Si and Se affect the bioavailability of cadmium(Cd)and lead(Pb)in soil and thereby their transfer to rice in Cd and Pb-polluted fields.In this study,seven treatments were set up in a field experiment conducted in a nonferrous metal mining area in Tongling City,Anhui Province,China:no Si/Se fertilization control(CK),basal Si/Se fertilization(Si-1/Se-1),basal and topdressing Si/Se fertilization(Si-2/Se-2),and basal,topdressing,and foliar Si/Se fertilization(Si-3/Se-3).The results indicated that compared to CK,rice yield increased by 3.94%-14.56%in the other treatments,with the most significant increase observed in Si-3 and Se-3.Additionally,the Cd content in brown rice decreased by 15.42%-51.55%,while Pb content decreased by 16.49%-47.18%.In all treatments except Si-1,both metal contents decreased to below the limits specified in China's food safety standard(GB 2762-2022).Furthermore,they impeded the translocation of these metals to the brown rice,thereby effectively diminishing metal accumulation in rice grain.The effect of Se fertilizer was better than Si fertilizer in decreasing the bioconcentration factors of Cd and Pb and inhibiting their translocation to brown rice.At the same time,the applications of Si and Se increased the Si and Se contents of rice aboveground parts,respectively,and the Se content of brown rice in Se-3 increased by 77.56%,meeting the Se enrichment standard(GB/T 22499-2008).The contents of diethylenetriamine pentaacetic acid-extractable Cd and Pb in soil decreased in all Si/Se treatments by 25.53%and 22.37%in Se-3,respectively.All Si/Se treatments reduced the acid-exchangeable and reducible Cd and Pb in soil and transformed them into the more stable oxidizable and residual fractions.This study revealed that the bioavailability of Cd and Pb in soil and their translocation to brown rice were significantly reduced by the basal application combined with topdressing and foliar application of Si and Se fertilizers.展开更多
基金supported by the Key Research and Development Program of Anhui Province,China(No.2022m07020004)the Natural Resources Science and Technology Project of Anhui Province,China(No.2022-k-8).
文摘Soil and foliar applications of silicon(Si)and selenium(Se)fertilizers can inhibit the transfer of heavy metals from the soil to crops.However,it remains unclear how Si and Se affect the bioavailability of cadmium(Cd)and lead(Pb)in soil and thereby their transfer to rice in Cd and Pb-polluted fields.In this study,seven treatments were set up in a field experiment conducted in a nonferrous metal mining area in Tongling City,Anhui Province,China:no Si/Se fertilization control(CK),basal Si/Se fertilization(Si-1/Se-1),basal and topdressing Si/Se fertilization(Si-2/Se-2),and basal,topdressing,and foliar Si/Se fertilization(Si-3/Se-3).The results indicated that compared to CK,rice yield increased by 3.94%-14.56%in the other treatments,with the most significant increase observed in Si-3 and Se-3.Additionally,the Cd content in brown rice decreased by 15.42%-51.55%,while Pb content decreased by 16.49%-47.18%.In all treatments except Si-1,both metal contents decreased to below the limits specified in China's food safety standard(GB 2762-2022).Furthermore,they impeded the translocation of these metals to the brown rice,thereby effectively diminishing metal accumulation in rice grain.The effect of Se fertilizer was better than Si fertilizer in decreasing the bioconcentration factors of Cd and Pb and inhibiting their translocation to brown rice.At the same time,the applications of Si and Se increased the Si and Se contents of rice aboveground parts,respectively,and the Se content of brown rice in Se-3 increased by 77.56%,meeting the Se enrichment standard(GB/T 22499-2008).The contents of diethylenetriamine pentaacetic acid-extractable Cd and Pb in soil decreased in all Si/Se treatments by 25.53%and 22.37%in Se-3,respectively.All Si/Se treatments reduced the acid-exchangeable and reducible Cd and Pb in soil and transformed them into the more stable oxidizable and residual fractions.This study revealed that the bioavailability of Cd and Pb in soil and their translocation to brown rice were significantly reduced by the basal application combined with topdressing and foliar application of Si and Se fertilizers.
