功能内生细菌Pn2在植物体内定殖对植物吸收积累PAHs的影响
毕业论文关键词：多环芳烃；功能内生细菌；定殖；降解
Effects of plant endophytic bacteria Pn2 on plant uptake of PAHs in plants
Abstract: In this study, we investigated the effects of the endophytic bacteria Pn2 on the absorption of phenanthrene (100 mg • kg-1) and pyrene (50 mg • kg-1) in the ryegrass.The results showed that the inoculation of endophytic bacteria Pn2 could effectively increase the biomass of plant aerial parts and reduce the accumulation of phenanthrene and pyrene in the soil roots and stems and leaves, thus alleviating the risk of plant PAHs pollution to avoid the organic pollution provides a theoretical basis. In this study, we chosen greenhouse experiments to investigate the colonization of PAH-degrading endophytic bacterium Massilia sp.Pn2 in plants and the influence of strain Pn2 on the uptake and degradation of PAHs by plants. The concentration of phenanthrene and pyrene in the soil are 100 and 50 mg•kg-1. The Biomass of ryegrass are increased by 18.31% and 30.53% in the endophyte-inoculated soil. About 74.20%－75.08% and 50.65%－51.75% phenanthrene and pyrene are disappeared in the soil after 30 days. The concentration of phenanthrene in the root and shoot are 39.20 and 5.50 mg•kg-1 in the endophyte-inoculated soil and the concentration of pyrene in the root and shoot are 78.25 and 8.94 mg•kg-1 in the endophyte-inoculated soil, which is higher than the ryegrass planted in the soil without endophyte-inoculated. Otherwise, the accumulation of phenanthrene and pyrene in the root and shoot are reduced by 11.00%、15.15% and 7.76%、16.67% in the endophyte-inoculated soil.
Key words: Polycyclic aromatic hydrocarbons (PAHs); Endophytic bacteria; Colonization; Degradation
目 录
摘要1
关键词1
Abstract1
Key words1
引言1
1 实验材料与方法2
1.1 实验材料 2
1.1.1 化学试剂和几个培养基2
1.1.2 准备供试植物和菌株3
1.2 实验方法 3
1.2.1 温室盆栽实验3
1.3 实验分析方法 3
1.3.1 测定植物的生物量3
1.3.2 测定功能内生细菌的定殖数量3
1.3.3 土壤和植物体内PAHs含量的测量3
1.4 数据处理分析 4
2 实验结果与分析4
2.1 对植物生物量的影响4
2.2 接种功能内生细菌Pn2对植物吸收降解PAHs的影响4
2.3 对土壤中PAHs的降解效果5
3 实验结果的讨论 6
3.1功能内生细菌的促生长作用6
3.2 菌株Pn2对植物吸收代谢PAHs的影响 6
4 展望6
致谢7
参考文献7
植物内生细菌Pn2在植物体内定殖对植物吸收PAHs的影响
多环芳烃(Polycyclic aromatic hydrocarbons, PAHs)是由多个苯环组成的，在自然界中持续存在的一种有机污染物，并具有致癌、致畸、致突变的“三致”作用[1]。PAHs具有很强的疏水性、自然状态下很难降解、常常在泥土中大量的积累，当多环芳烃被植物吸收并大量积累后，容易通过食物链富集，人们食用了富集大量多环芳烃的动植物后，人体体内会大量积累，超量的多环芳烃会严重危害人体健康[2-4]。因此，如何减轻植物体内的PAHs污染风险，更好的保障农产品的质量与安全成了近年来环境学者努力的方向。