The pot experiment was conducted to study the effects of combined chelator EDTA, EDDS, AES, IDSA and AM on heavy metals uptake by maize(Zea mays L.). Modified BCR three-step method was employed to analyze the speciations of mycorrhizo-sphere heavy metals in the soil. AES and IDSA treatment significantly improved the shoot heavy metals uptake, especially for Cd and Cu, Cd concentration was 6.2 and 6.3 times, Cu concentration was 21.8 and 7.7 times than that of control. Cd concentration of AM&EDDS was 6.4-fold of EDDS treatment, increased by 120.7% compared to single AM addition. In comparison with AES treatment, Pb concentration of AM&AES treatment was increased by 71.5%, so was 32.0%of AM&IDSA compared to IDSA treat-ment. Compared AM&AES, AM&IDSA with single AM treatment, Zn concentration was increased by 134.1%and 21.8%, Cu and Pb concentration of former was respectively 8.4 and 3.3, 11.9 and 8.7 times than that of latter. Chelator addition also enhanced root heavy metal concentration obviously, Pb concentration of EDTA treatment was 5.0 times that of control, Cu concentration of AES and IDSA treatment was increased by 229.1% and 131.0%. The roots Cd concentration of combined AM and chelator decreased compared to single chelator treatment, the trend was opposite to shoots. Zn concentration of AM&EDDS was increased by 48.6%than EDDS treatment, so was 24.6%of AM&AES compared to AES treatment. Zn concentration of AM&EDTA, AM&EDDS and AM&AES treatment were increased by 70.0%, 90.9%and 51.3%compared to AM treatment, Cu concentration of former was 2.6, 1.8 and 4.0 times than latter, so was 4.5, 4.2 and 2.8 times of Pb concentration. Mycorrhizosphere soil Zn, Cu, Pb bound relative content was significantly higher than non-rhizosphere. The results showed that new chelator AES and IDSA were significantly effec-tive for heavy metals uptake and accumulate by maize. Combing chelator with AM mycorrhizal enhance the absorption and accumu-lation of heavy metals by maize than single AM or chelator treatment, reinforce the effect of phytoextraction. AM mycorrhizal changed the speciations of heavy metals in the rhizosphere soil, making them transferred from loose combination state to tighten, reducing the bioavailability of heavy metals and the poison of excessive heavy metal to the host plant.%通过温室根箱盆栽试验研究4种螯合剂EDTA、EDDS、AES和IDSA与AM菌根单一或联合对植物吸收重金属的影响，并通过改进的BCR三步法分析了玉米Zea mays L.菌根根际重金属的化学形态变化。AES和IDSA处理显著提高了玉米地上部重金属的吸收，对Cd、Cu的作用最为显著，Cd质量分数是对照的6.2倍和6.3倍，Cu质量分数是对照的21.8倍和7.7倍。AM&EDDS处理Cd的质量分数是EDDS处理的6.4倍，较单一AM处理增加了120.7%；AM&AES处理的Pb质量分数较之AES处理增加了71.5%，AM&IDSA较之IDSA处理亦增加了32.0%。AM&AES、AM&IDSA处理较之单一AM处理，Zn质量分数增加了134.1%和21.8%，Cu质量分数前者是后者的8.4倍和3.3倍，Pb质量分数前者是后者的11.9倍和8.7倍。添加螯合剂处理较之对照亦显著提高了玉米根部重金属的质量分数（P<0.05），其中EDTA处理Pb质量分数是对照的5.0倍，AES和IDSA处理Cu质量分数增加了229.1%和131.0%。AM与螯合剂联合处理后，玉米根部Cd质量分数较之单一螯合剂处理降低，与地上部呈相反趋势；AM&EDDS处理较之EDDS处理，Zn质量分数增加了48.6%，AM&AES与AES处理对比亦增加了24.6%；AM&EDTA、AM&EDDS和AM&AES较之AM处理玉米根部Zn质量分数分别增加了70.0%、90.9%和51.3%，Cu质量分数前者是后者的2.6倍、1.8倍、4.0倍， Pb质量分数前者是后者的4.5倍、4.2倍和2.8倍。AM处理下根际土壤Zn、Cu、Pb结合态相对含量明显高于非根际。结果表明，新型螯合剂AES和IDSA对玉米地上部和根部重金属的吸收积累有较明显的促进作用；螯合剂和AM菌根联合提高了单一接种AM菌根或者添加螯合剂时玉米对重金属的吸收积累量，强化了植物提取的效果；AM菌根改变了根际土壤中重金属的形态，菌根的存在使得重金属的形态由松结合态向紧结合态转移，降低了重金属的生物有效性及过量重金属对宿主植物的毒害。
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