溶杆菌种群多样性及其典型种菌次生代谢产物生物学特性研究

Lysobacter spp. is a new-type, potential useful biocontrol resources. Previous research showed that several Lysobacter strains were efficiently controlled soil-borne diseases and yield increase effects of many important crops, such as cruciferous vegetables and Amorphophallus Konjac crops. However, not only the Lysobacter spp population diversity and ecological characteristics, but also the interaction between ecological factors and the population density were remains unknown. Based on the existing research, this proposal will investigate the population diversity and distribution of Lysobacter spp. Initially, the new Lysobacter strain resouces was excavated by using further isolation and identification method. After monitoring the population changes of Lysobacter spp. combined with real-time fluorescence quantitative PCR, the regular pattern of dominant species distribution will be elucidated, which were quantified by the soil physical and chemical characteristics, vegetation type in different ecological region of low latitude plateau. Typical Lysobacter strains with growth-promoting and disease-preventing effect were screened and obtained through field evalution method. Meanwhile, the active secondary metabolites from Lysobacter typical strain will be further analyzed. The research also studied the effects of typical strains and its active compounds on the pathogen population variation and soil microbiology diversity by using ecological research methods. Therefore, the research will elucidate the ecological effect and mechanism action of Lysobacter agents and its active compounds on the growth-promoting and root rot disease-preventing of Panax notoginseng.The research achivement has great significance for understanding the ecological mechanism of Lysobacter populations and practical application value of microbial resources in biological control of soil-borne disease.

溶杆菌种群是一类新型和有应用潜力的生防菌资源，研究证实溶杆菌种群对蔬菜、魔芋等多种重要经济作物具有防病、增产效果，但溶杆菌种群的多样性、生态学特点及其与环境因子的互作未知。 本项目拟在已有的溶杆菌菌株鉴定研究基础上，通过尽一步系统分离、鉴定溶杆菌种群，研究溶杆菌种群多样性及其分布规律，挖掘新的溶杆菌菌种资源；结合实时荧光PCR定量监测溶杆菌种群变化，分析低纬高原生态环境下土壤理化特性、植被类型对溶杆菌种群分布的影响规律。通过田间试验筛选具有促生和防病作用的代表菌株，对其次生代谢产物活性组分进行深入研究；利用生态学研究手段，研究代表种菌及其活性组分对病菌种群消长和根际微生物多样性的影响，解析溶杆菌及其活性组分对三七生长和根腐病调控的生态效应和作用机理，这对解析溶杆菌种群的生态学特征具有重要的科学意义，也为其应用防治病害具有重要的实践应用价值。

该项目利用传统微生物、分子生物学和现代化学和生态学技术开展系统研究，取得了一系列创新性成果：1）发掘了溶杆菌属不同种的微生物资源，分析了溶杆菌种群遗传多样性、优势种群及其分布特点；建立了土壤中溶杆菌属、抗生素溶杆菌特异性Q-PCR检测技术体系；2）多种途径解析了溶杆菌属典型种的次生代谢产物种类，弄清了抗生素溶杆菌产吩嗪类化合物的种类及其生物活性；3）试验证实抗生素溶杆菌、辣椒溶杆菌代表菌株具有广谱抑菌、促进三七等作物生长和防控三七根腐病、十字花科蔬菜根肿病等作物土传病害，优化了抗生素溶杆菌高产吩嗪的发酵培养成分和发酵条件和探索了溶杆菌生防种子包衣剂的配方比例和实际施用技术，发酵生产抗生素溶杆菌生防菌剂，配制了溶杆菌组合，为今后开发此类生物农药，示范应用于三七生态种植，具有重要的应用价值；研究期间共发表论文12篇，其中SCI论文5篇，项目参加人员1 人获得“云南省中青年学术带头人”称号，培养博士研究生1名，硕士研究生3名；申报国家发明专利8项，其中授权3项，受理5项。