矿物硅肥与微生物菌剂对水稻吸收积累镉的影响

Effects of mineral silicon fertilizer and microbial agent on uptake and accumulation of cadmium by rice

采用室外盆栽试验和田间随机区组试验相结合的方法,研究基施矿物硅肥、微生物菌剂、矿物硅肥与微生物菌剂组配施用,对湖南地区晚稻成熟期内各部位中Cd的含量及产量的影响。结果表明,在盆栽试验中,与CK相比,微生物菌剂处理对水稻根部、茎鞘、谷壳和糙米中Cd含量的抑制效果最佳,降低幅度分别为46.19%、52.46%、38.39%和55.31%,而矿物硅肥处理对叶片中Cd含量的抑制效果最佳,降低幅度为54.39%;在田间随机区组试验中,与CK相比,矿物硅肥处理对水稻根部、茎鞘和叶片中Cd含量的抑制效果最佳,降低幅度分别为73.91%、71.28%和76.77%,而微生物菌剂处理对谷壳和糙米中Cd含量的抑制效果最佳,降低幅度分别为65.52%和69.57%。对于轻度污染土壤,施用三种改良剂后,糙米中Cd含量明显降低,分别为0.09、0.07、0.12 mg·kg^(-1),均能达到国家食品卫生标准(Cd<0.2 mg·kg^(-1));水稻产量方面,施用改良剂均能使水稻增产,其中以矿物硅肥+微生物菌剂组配处理的效果最为显著,在盆栽试验和田间随机区组试验中,分别比对照增产28.06%和31.1%。

In pot and field experiments, the effects of base mineral silicon fertilizer and microbial agent alone and in combination on the concentrations of Cd in different parts and the yield of late rice were investigated during maturation period in Hunan region. Results showed that the microbial agent was more effective in reducing Cd accumulation in rice than mineral silicon fertilizer was. The Cd content in roots,leaves, sheaths and chaffs was 46.19%, 52.46%, 38.39% and 52.46% lower in microbial agent treatment than in CK, respectively. The mineral silicon fertilizer was more useful for reducing Cd content in the leaves, with 54.39% Cd reduction compared with CK in the pot experiment. In the field experiment, the mineral silicon fertilizer was the most effective in inhibiting Cd accumulation in roots, leaf sheaths and blades of rice among the three treatments, with a 73.91%, 71.28%, and 76.77% reduction in Cd content as compared with CK, respectively,while in microbial agent treatment the Cd content in chaff and brown rice reduced by 65.52% and 69.57%, respectively, compared with CK.In slightly contaminated soil, three treatments significantly reduced Cd content in brown rice, which was 0.09 mg·kg-1, 0.07 mg·kg-1, and0.12 mg·kg-1in silicon fertilizer, microbial agent and their combination, respectively, meeting the national food health standards（Cd〈0.2mg·kg-1）. The yields of the rice were significantly increased by three treatments, with greatest yield increase found in combined silicon fertilizer and microbial agent treatment, in which there were 31.1% and 28.06% yield increases in the pot and field experiments, respectively,as compared with the CK.