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采用CDM培养基对湖南锡矿山Sb矿区周边重金属污染土壤中耐Sb、促生细菌进行分离、筛选。结合细菌形态、生理生化检测、16S rRNA基因序列分析等方法确定其分类地位,并开展Sb(Ⅲ)耐受性、Sb(Ⅲ)吸附性、Sb(Ⅲ)氧化性、促生特性的测定、不同pH和盐度适应性研究,以及利用盆栽试验研究菌株在不同浓度锑处理下对油菜生长的影响。结果表明:从Sb污染土壤中共筛选出4株具有较强耐Sb、促生细菌,初步鉴定其分别属于Pseudomonas、Ensifer、Raoultella和Stenotrophomonas属,编号分别为XKS-1、XKS-2、NXH-2和NXH-3。4株菌对Sb(Ⅲ)的最低抑制浓度均在25 mmol·L~(-1)以上,且具有一定吸附和氧化Sb(Ⅲ)的能力。4株菌均可分泌IAA和铁载体;pH和盐度对4株细菌生长的影响存在较大差异。盆栽实验结果表明,在低浓度Sb和中等浓度Sb的胁迫条件下,与未加菌的对照植株相比,4株细菌分别使油菜株高、根长、叶绿素a和叶绿素b含量分别增加4%~26%、13%~32%、23%~35%和5%~32%;在高Sb浓度下,4株细菌对油菜上述指标没有显著增加作用。研究结果说明:4株耐Sb、促生菌株对环境的适应性较强,在Sb污染矿区土壤修复中具有潜在的应用价值。
CDM medium was used to separate and screen anti-Sb and protozoal bacteria in the heavy metal-contaminated soils around the Sb mine in Hunan Province. The taxonomic status of Sb (Ⅲ), Sb (Ⅲ), Sb (Ⅲ), and the growth-promoting properties were determined with the method of bacterial morphology, physiological and biochemical detection and 16S rRNA gene sequence analysis. Different pH and salinity adaptability studies, and the use of pot experiments to study the strains of antimony in different concentrations of rape on the growth. The results showed that four strains with strong resistance to Sb and growth-promoting bacteria were screened from Sb-contaminated soils, and were identified as Pseudomonas, Ensifer, Raoultella and Stenotrophomonas respectively, and the numbers were XKS-1, XKS-2 and NXH-2 And NXH-3.4 against Sb (Ⅲ) were above 25 mmol·L -1, and had the ability to adsorb and oxidize Sb (Ⅲ). All four strains could secrete IAA and iron carrier. The effects of pH and salinity on the growth of four strains were quite different. The results of pot experiment showed that the four strains of bacteria increased the plant height, root length, chlorophyll a and chlorophyll b content by 4%, respectively, under the stress of low concentration of Sb and medium concentration of Sb, ~ 26%, 13% -32%, 23% -35% and 5% -32%, respectively. Under the high Sb concentration, the four strains had no significant effect on the above indexes of rapeseed. The results showed that four strains of anti-Sb and progeny strains had strong adaptability to the environment and had potential application value in soil remediation of Sb contaminated area.