中文摘要：

以菲和芘为多环芳烃（PAHs）代表物，紫花苜蓿（Medicagosativa L．）为宿主植物，研究了丛枝菌根（AM）对土壤中PAHs降解的影响。供试5种丛枝菌根真菌（AMF）为Glomus mosseae、Glomus etunicatum、Glomus versiforme、Glomus constrictum和Glomus intraradices。土样中菲和芘的起始浓度分别为0-170．6mg·kg^-1和66．06mg·kg^-1。结果表明，PAHs污染土壤中，AMF对紫花苜蓿的侵染状况良好。20～60d，供试5种AMF对土壤中菲的修复效率均在91％以上。与有植物无AMF对照相比，接种AMF后土壤中菲和芘的残留浓度明显降低，其中Glomus mosseae、Glomus verbiforme、Glomus constrictum对菲和芘降解的促进效果最好。AM作用下，紫花苜蓿吸收积累对菲、芘降解的贡献率小于1．4％；而接种AMF明显提高了土壤微生物的数量和活性，这应是AM促进土壤中菲、芘降解的一个重要机理。

英文摘要：

Effect of Arbuscular mycorrhizae （AM） on degradation of phenanthrene and pyrene as representatives of PAHs in soils was investigated taking alfalfa （Medicagosativa L.） as the host plant. Five arbuscular mycorrhizal fungi （AMF） including Glomus mosseae, Glomus etunicatum, Glomus versiforme, Glomus constrictum, and Glomus intraradices were experimented. The initial concentrations of phenanthrene and pyrene in soils were 0- 170.6 mg·kg^-1 and 66.06 mg·kg^-1, respectively. In 20-60 days, more than 91% of phenanthrene was removed from soils using AM system. The residual concentrations of tested PAHs were significantly lower in soils with AMF-inoculation than those without AMF. And Glomus mosseae, Glomus versiforme, and Glomus constrictum were of the best AMF for the promotion of PAH degradation in soils. One notes that plant accumulation of tested PAHs contributed less than 1.4% to the degradation of these chemicals in soils. However, the presence of AMF significantly promoted the microbial activities in soils, and consequently enhanced the degradation of PAHs in soils, which would be a predominant mechanism of the promoted degradation of PAHs in soils by AM.