摘要
对四川广元烟草主产区三个种植基地的烟草根际固氮菌进行筛选,分离出28株具有固氮活性的菌株。经扩增r DNA限制性酶切片段分析法(ARDRA)初步分类,共获得5个操作分类单元(OTU),并由16S rDNA序列进行了分析鉴定。结果表明不同分类单元分别是:苏云金芽孢杆菌、枯草芽孢杆菌、甲基营养型芽孢杆菌、巨大芽孢杆菌和炭疽杆菌。优化了N7菌株(巨大芽孢杆菌)培养条件,确定其最佳碳源为蔗糖,最适宜初始pH值为7.5,最适温度为30℃。
Twenty eight diazotrophs were isolated from rhizosphere soil samples from Guangyuan tobacco growing area, Sichuan province. These diazotrophs were isolated by using free nitrogen medium. Amplified r DNA restriction analysis(ARDRA)showed that all strains isolated could be classified into 5 Operational Taxonomic Units(OUT). Different OUTs was identified by 16 S r DNA sequencing, and those were identified as Bacillus: Bacillus thuringiensis; Bacillus subtilis; Bacillus methylotrophicus; Bacillus megaterium and Bacillus anthracis. The batch culture conditions of isolate N7(Bacillus megaterium) were optimized via adjusting carbon sources, temperature and p H values. It was found that sucrose is the best carbon source, and the best initial p H value is 7.5, and the best temperature is 30℃.
出处
《中国烟草学报》
EI
CAS
CSCD
北大核心
2015年第1期89-94,共6页
Acta Tabacaria Sinica
基金
北京高等学校青年英才计划项目(No.YETP0394)
关键词
烟草
固氮菌
筛选
16s
RDNA
优化培养
tobacco
nitrogen-fixing bacteria
screening
16S rDNA
optimization