金属抗性促生菌对玉米的生长和累积镉的影响  

Effects of Metal-Resistant Plant Growth Promoting Bacteria on Growth and Cadmium Accumulation of Corn

作　　者：唐飞[1] 陈亚刚[1] 龙新宪[1] 

机构地区：[1]华南农业大学资源环境学院,广州510642

出　　处：《农业环境科学学报》2013年第10期1941-1949,共9页Journal of Agro-Environment Science

基　　金：国家自然科学基金(40973055);国家自然科学-广东省联合基金(U0833004)

摘　　要：在LB培养基中添加不同浓度Cd2+后,促生菌Ⅳ8R3、Ⅱ2R3不仅能正常生长繁殖,而且具有较强吸附、积累Cd的能力。在不同Cd污染水平的土壤上,单独接种促生菌Ⅳ8R3或Ⅱ2R3均显著促进了第一季玉米的生长,但在Cd添加量为1 mg·kg-1或5 mg·kg-1的土壤上,同时接种Ⅳ8R3+Ⅱ2R3反而抑制了玉米的生长;然而,单独或同时接种促生菌Ⅳ8R3或Ⅱ2R3对第二季玉米的生长均没有产生显著影响。接种促生菌Ⅳ8R3、Ⅱ2R3在一定程度上可以升高土壤pH和降低土壤有效Cd含量,在Cd污染水平较高的土壤表现更为显著。当土壤Cd含量较高时(Cd添加量为5、10 mg·kg-1),单独或同时接种菌株Ⅱ2R3、Ⅳ8R3能显著抑制玉米对Cd的吸收或向地上部转运,地上部Cd含量显著降低;而当土壤Cd含量较低时(对照土壤和Cd添加量为1 mg·kg-1的土壤),单独或同时接种Ⅱ2R3、Ⅳ8R3反而促进了玉米对Cd的吸收。Plant growth promoting bacteria（PGPB ） might play a certain role in phytoremediation. A greenhouse experiment was carried out to study plant growth and Cd uptake of corn inoculated with two Cd-resistant PGPB, 112R3 and 1VsR3, in soils spiked with Cd at O, l, 5 mg kg-l and 10 mg kg-1. Strains 2R3 and IV 8R3 not only grew well in Luria broth （ LB ） media added with different concentrations of Cd, but al- so accumulated Cd from the medium. In the first season, corn growth was promoted by individual inoculation of strains ~ 2R3 or 1VsR3, but inhibited by simultaneous inoculation in soils with 1 mg-kg-j Cd or 5 rag＂ kg-1 Cd addition. In the second season, however, all inoculation treatments had no significant effects on corn growth. Compared to the control, all inoculations increased Cd uptake by corn in soils with low Cd levels（ 1 mg-kg-1 Cd addition）, while decreased Cd absorption and transportation in corn in high Cd soils（5 mg kg-1 or lO mg kg-1 Cd ad- dition）. To some extent, inoculation of the strains I12R3 and IVsR3 increased soil pH, but decreased soil bioavailable Cd. Our results indicate that inoculation with metal-resistant PGPB to heavy Cd-contaminatcd soils promotes plant growth and inhibits the uptake and transportation of Cd in corn.

关 键 词：镉 金属抗性促生菌 玉米 

分 类 号：X53[环境科学与工程—环境工程]