草业科学2017，Vol.34Issue(12)：2454-2463,10.DOI:10.11829/j.issn.1001-0629.2017-0055
3株分离自高寒草甸根际芽孢杆菌的分子鉴定及其生物活性
Molecular identification and biological activity of three Bacillus strains isolated from an alpine meadow rhizosphere in Qinghai Province
摘要
Abstract
For the purpose of restoring degraded vegetation and improving the aboveground biomass of grass-land,the biological activity of three strains of Bacillus spp.bio-control agents were isolated and screened. Three strains isolated from an alpine meadow (Kobresia pygmaea)rhizosphere in Huangnan Autonomous Pre-fecture,Qinghai Province,were identified by 16S rDNA and gyrB partial sequence analyses.Antagonistic ac-tivity of strains to pathogenic fungi were determined by the flat confrontation test,and the growth-promoting activities of strains were checked by soaking plant seeds in strain suspension (106 cfu·mL-1 of cell concentra-tion).In addition,cellulose-degrading activities of strains were checked with carboxymethylcellulose (CMC) plate test,Gram staining,and 3,5-dinitrosalicylic acid (DNS)methods;moreover,cellulase coding genes of the strains were amplified and analyzed.The results showed that the isolate of HNC3 was identified as Bacillus pumilus,and isolates of HNC8 and HNC11 were identified as B.thuringiensis.The three strains presented distinct antagonistic activity to Fusarium graminearum S and Fusarium oxysporum (inhibition zone diameter ≥ 11 mm).Furthermore,the strains showed obvious germination and growth-promoting activity af-ter soaking the wheat seeds in Bacillus suspension.The effect of the isolate of HNC3 on the growth of wheat seedlings was significant;the rate of bud and root length growth increased by 55% and 80%,respectively.The cellulase activity of the isolate of HNC3 reached 367.51 U·mL-1 ,and its cellulase coding genes could be am-plified including lichenase (blg1S),mannosidase (ManSig),and xylanase (xynD,xynB).The three Bacillus strains used as bio-control agents all showed antagonistic,plant growth-promoting,and cellulose-degrading ac-tivities,which present future research opportunities into the potential of their application in the recovery of plateau grassland vegetation,as well as in the field of ecological animal husbandry.关键词
高寒草甸/生防芽孢杆菌/分子鉴定/催芽促生Key words
alpine meadow/Bacillus bio-control agent/molecular identification/plant growth promotion分类
农业科技引用本文复制引用
吴晓晖,谢永丽,Renato D'Ovidio,张英,芦光新,辛总秀,Stefania Masci..3株分离自高寒草甸根际芽孢杆菌的分子鉴定及其生物活性[J].草业科学,2017,34(12):2454-2463,10.基金项目
青海省科技厅应用(基础)研究项目(2015-ZJ-732) （基础）
青海省科技厅国际合作项目(2013-H-805) （2013-H-805）
国家自然基金项目(31660543) （31660543）
