摘要
为发掘耐受重金属的微生物资源和高效阻控重金属向蔬菜转移的修复生物材料,从生长于南京某矿区周边菜地的辣椒(Capsicum annuum)和圣女果(Lycopersicon esculentum)根际土壤中筛选耐重金属芽孢杆菌,研究其促生特性和阻控辣椒果实吸收Cd、Pb的作用。本研究筛选到7株耐Cd、Pb并具有分泌胞外多糖、吲哚乙酸和铁载体的芽孢杆菌,分别属于Bacillus megaterium、B.aryabhattai、B.velezensis和Lysinibacillus fusiformis。菌株在24 h时对溶液中Cd的去除率范围为30%~39%,对Pb的去除率在4.3%~25.6%。菌株L11、L15和L44能够显著促进辣椒生长,6株芽孢杆菌能显著降低辣椒果实中Cd和Pb含量。接种菌株B.megaterium L44使辣椒果实中Cd、Pb含量比不接菌对照分别降低39.1%和81.3%,Cd、Pb含量分别降低至0.07 mg·kg^(-1)和0.20 mg·kg^(-1)。研究表明B.megaterium L44是一株能够阻控辣椒果实积累铅镉的植物促生芽孢杆菌,具有阻控蔬菜吸收重金属、用于蔬菜农田安全生产的潜在应用价值。
In order to identify agents for reducing the accumulation of heavy metals in vegetables grown in contaminated soils, heavy metaltolerant spore-forming bacteria were isolated from the rhizosphere of Capsicum annuum and Lycopersicon esculentum grown on farmland near mines in Nanjing, China, and the effects of the isolated bacteria on the growth and Cd and Pb uptake of pepper plants were assessed.Seven heavy metal-tolerant spore-forming bacterial strains were isolated and found to possess a variety of plant growth-promoting properties, such as phosphate solubilization and the production of indole acetic acid（IAA）, siderophores, and polysaccharides. The bacteria were identified as Bacillus megaterium, B. aryabhattai, B. velezensis, and Lysinibacillus fusiformis, based on 16 S r RNA gene sequences and phylogenetic analysis. The bacteria reduced the concentrations of water-soluble Cd and Pb in the solution by 30%-39% and 4.3%-25.6%, re-spectively, and strains L11, L15, and L44（B. megaterium）significantly promoted plant growth and reduced fruit concentrations of Cd and Pb. Furthermore, the lowest Cd（0.07 mg·kg^-1）and Pb（0.2 mg·kg^-1）levels were observed in the fruits of peppers inoculated with B.megaterium L44, which significantly reduced the heavy metals by 39.1% and 81.3%, respectively. Therefore, B. megaterium L44 is a more efficient agent for reducing the heavy metal levels of vegetables grown in contaminated soil.
作者
杨丽
燕传明
贺卓
盛下放
何琳燕
YANG Li;YAN Chuan-ming;HE Zhuo;SHENG Xia-fang;HE Lin-yan(Key Laboratory of Agricultural and Environmental Microbiology,Ministry of Agriculture,College of Life Sciences,Nanjing Agricultural University,Nanjing 210095,China)
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2018年第6期1086-1093,共8页
Journal of Agro-Environment Science
基金
国家自然科学基金项目(41471273)
关键词
芽孢杆菌
辣椒
镉
铅
阻控剂
Bacillus
pepper
cadmium
lead
immobilizing agent
