作　　者： ; ; ; ;

机构地区： 湖南城市学院建筑与城市规划学院

出　　处： 《西北植物学报》 2016年第10期2030-2037,共8页

摘　　要： 为探讨镉（Cd）胁迫条件下蒌蒿对促生细菌（PGPB）的响应机制,以芽孢杆菌T3（Bacillus sp.）菌株为对象,通过盆栽试验,研究不同Cd处理水平下芽孢杆菌T3菌株对蒌蒿生长、生理、Cd富集转运以及根际微生物的影响。结果表明：（1）在Cd胁迫条件下,芽孢杆菌T3菌株可显著促进蒌蒿地上部、地下部及总干物质的积累,但对株高和根冠比的影响不明显。（2）芽孢杆菌T3菌株能显著促进Cd胁迫条件下蒌蒿对Cd的富集与转运,相比单一Cd胁迫,蒌蒿地上部生物富集系数（BCF）增加了8.3%-29.3%,地下部BCF减少了6.6%-11.1%,同时转运系数（TF）增加了20.8%-38.3%。（3）在Cd胁迫和芽孢杆菌T3菌株的共同作用下,蒌蒿叶绿素a、叶绿素b和总叶绿素含量明显增加。（4）芽孢杆菌T3菌株使Cd胁迫条件下蒌蒿体内丙二醛（MDA）含量显著减少,超氧化物歧化酶（SOD）、过氧化物酶（POD）和过氧化氢酶（CAT）活性明显增加,可有效抵御由Cd胁迫所产生的氧化伤害。（5）芽孢杆菌T3菌株能显著增加Cd胁迫条件下蒌蒿根际土壤细菌、放线菌数量及微生物总量,可减少蒌蒿根际土壤真菌的数量,但与对照差异不显著。研究表明,在Cd胁迫条件下芽孢杆菌T3菌株对蒌蒿生长、生理和根际土壤微生物环境可产生积极影响,可增强蒌蒿植物对Cd胁迫环境的适应性,从而提高其对Cd的耐受能力。 To explore response mechanism of Artemisia selengensis on plant growth-promoting bacteria （PGPB） under cadmium stress, this study examined the effects of strain T3 on growth, physiology charac- teristics, cadmium concentration and translocation and rhizosphere microorganisms of A. selengensis under different concentrations of cadmium by pot experiment. The results indicated that （1） Bacillus sp. T3 could distinctly promote the accumulation of shoot, root and total dry weight, but had no significant differ ence in plant height and root-shoot ratio of A. selengensis under cadmium stress. （2） Bacillus sp. T3 coulddistinctly increase A. selengensis to cadmium concentration and translocation, bioconcentration factors （BCF） of cadmium in shoot increased by 8.35-29.3%, translocation factors（TF） increased by 20.8%- 38.3%, but BCF in root reduced by 6.6%-11.1% compared with the single cadmium stress. （3） Under the joint action of cadmium stress and Bacillus sp. T3, A. selengensis chlorophyll a, chlorophyll b and to- tal chlorophyll contents significantly enhanced compared with the single cadmium stress. （4） Bacillus sp. T3 could significantly enhance the activities of superoxide dismutase（SOD）, peroxidase（POD） and catalase （CAT）, whereas significantly reduced the malondialdehyde（MDA） content of A. selengensis. Therefore it could effectively strengthen A. selengensis to resist oxidation damage produced by cadmium stress. （5） Under cadmium stress, Bacillus sp. T3 could significantly improve the number of bacteria, actinomyces and the total number of microorganisms of A. selengensis rhizosphere soil, but could not distinctly reduce the number of fungi compared with CK. The study suggested that Bacillus sp. T3 was conducive to im- prove growth, physiology and rhizosphere microorganisms environment of A. selengensis and then strengthen A. selengensis adaptability to cadmium stress environment as well as tolerance.

关 键 词： 促生细菌 镉胁迫 蒌蒿 生长生理 根际微生物

领　　域： [生物学]