To investigate the effects of different silicon fertilizer treatments on cadmium(Cd)accumulation in various organs of rice plants,the study conducted a field experiment with the conventional rice Zhuxiang 19 and three-line hybrid rice Yixiangyou 2115 as experimental materials.Five treatments were set up under a total silicon application rate(SiO2)of 3 000 kg/hm2:CK(no silicon application),Si1(one-time silicon application at the transplanting stage),Si2(split silicon application at the transplanting,jointing,and heading stages in a ratio of 5∶2∶3),Si3(split silicon application at the jointing and heading stages in a ratio of 4∶6),and Si4(split silicon application at the jointing and heading stages in a ratio of 6∶4).The results showed that all silicon application treatments reduced the Cd contents in various aboveground organs of rice at the jointing,heading,and maturity stages;Cd accumulations in various aboveground organs at the heading and maturity stages;Cd transport coefficients from roots to various aboveground organs(stems,leaves,rice husks,branches,and brown rice)and from various aboveground organs(stems,leaves,rice husks,and branches)to brown rice;and Cd enrichment indexes of various organs(roots,stems,leaves,rice husks,branches,and brown rice).Among the various silicon application treatments,Si2 treatment showed better effects in reducing Cd.Under Si2 treatment,the Cd contents in brown rice of Zhuxiang 19 and Yixiangyou 2115 were significantly lower than those under CK,with reductions of 47.6%and 48.0%,respectively;the Cd contents in roots,stems,leaves,panicles,and branches at the heading stage were 4.0%and 3.6%,29.0%and 31.3%,38.8%and 43.0%,29.9%and 31.9%,and 28.6%and 31.8%lower than those under CK,respectively;the Cd contents in roots,stems,leaves,rice husks,and branches at the maturity stage were 8.4%and 10.6%,30.4%and 33.5%,36.2%and 37.1%,28.2%and 31.8%,and 34.1%and 36.8%lower than those under CK,respectively;the Cd enrichment indexes of roots,stems,leaves,rice husks,branches,and brown rice were 7.6%and 8.7%,13.6%and 17.6%,27.8%and 30.4%,28.6%and 29.4%,25.0%and 26.3%,and 47.1%and 50.0%lower than those under CK,respectively.In addition,the decreases in the Cd transport coefficients from rice husks,branches,leaves,and stems to brown rice under Si2 treatment were also the greatest among various silicon application treatments.In conclusion,split silicon application at the transplanting,jointing,and heading stages in a ratio of 5∶2∶3 has a relatively better effect in reducing Cd.