土壤微生物中向日葵核盘菌抗性资源的挖掘及分子鉴定
Mining and Molecular Identification of Resistant Resources of Sclerotinia(Sclerotinia sclerotiorum) of Sunflower in Soil Microorganisms

为从不同来源土壤中筛选对向日葵菌核病具有较强拮抗能力的拮抗菌株，并进行分子鉴定，分别用PDA、MDA培养基培养核盘菌(Sclerotinia sclerotiorum)菌丝。结果表明，PDA培养基核盘菌菌丝生长较快，MDA培养基核盘菌菌核形成数量较多。从采集到的5个土壤样品中共分离到微生物单株26株，经过筛选，获得3株具有较好拮抗效果的细菌菌株，分别命名为BMD1、BMD2和BMD3。通过Blast对16S rDNA序列对比分析并结合构建系统发育树分析表明，BMD1与Bacillus subtilis（X60646）亲缘关系较近，序列相似度高于99%；BMD2与BMD3有2个碱基差异，二者同Bacillus pumilus（AB098578）、Bacillus altitudinis （AJ831842）、Bacillus stratosphericus（AJ831841）和Bacillus aerophilus（AJ831844）处于系统发育树同一分枝。
PDA and MDA medium were used to culture mycelium of Sclerotinia(Sclerotinia sclerotiorum). The result showed that mycelium of Sclerotinia(Sclerotinia sclerotiorum) grew faster in PDA medium and had larger quantities of Sclerotinia(Sclerotinia sclerotiorum)formation in MDA medium. 26 microbial strains were isolated from 5 soil samples，and 3 antagonistic strains （BMD1, BMD2, BMD3）had better antagonistic effect after screening, BMD1 had close relationship with Bacillus subtilis (X60646) after comparative analysis of 16S rDNA sequences by BLAST combined with phylogenetic tree， which sequence similarity was higher than 99%. There were two bases difference between BMD2 and BMD3, and both of them were the same branch with Bacillus pumilus (AB098578), Bacillus altitudinis (AJ831842), Bacillus stratosphericus (AJ831841) and Bacillus aerophilus (AJ831844) in phylogenetic tree.