农药对三七土壤放线菌群落结构及其功能的影响

Sanqi (Panax notoginseng), an endemic species in China, is a valuable Chinese Traditional Medicine. Excessive chemical pesticides, especially fungicides are applied to control the damaging and disastrous diseases, causing pesticide residues in medicinal materials, soil pollution, and microbial imbalances. Actinbacterial flora, plays important roles in the micro-ecology of soil and the health-keeping of Panax notoginseng. However, there is no report about the affection of pesticides on the actinobacterial community and their ecological functions. In this proposal, culture-independent (based on the next-generation sequencing techniques like MiSeq, and bioinformatic analysis) and culture-dependent approaches will be employed to investigate the affection of pesticides on the actinobacterial community and their ecological functions. The changes will be analyzed by the data collected after applying the selected fungicides which are widely applied in cultivation of notoginseng. The obtained results will be helpful in selecting fungicides, investigating the ecological functions of actinobacterial flora, and interpreting the relationship among pesticides, actinobateria flora and replanting obstacles in notoginseng cultivation. The culturable actinobacterial isolates will be screened as biocontrol agents (BCAs) for controlling the notoginseng phytodiseases.

三七为我国特有的名贵中药，但严重病虫害需大量地使用农药而致农残超标，污染环境及破坏土壤微生态平衡。放线菌在土壤微生物生态和三七健康生长过程中起着重要作用，但施用农药对三七土壤放线菌及其生态功能的影响研究尚缺。本项目选取5种常用的杀菌剂，以控制施药的方式，采用免培养技术（MiSeq高通量测序、生物信息学分析）和纯培养技术研究农药处理后三七土壤中放线菌群落组成以及功能基因构成，分析农药影响下的土壤中放线菌群落结构及其功能在三七生长过程中的变化趋势。研究结果有助于揭示农药在三七种植土壤中对放线菌群落及功能的影响，了解放线菌在三七生长过程中的生态功能，探索农药、放线菌生态功能与三七连作障碍的关系；为开发防治三七病害的生防放线菌剂及生物农药提供菌种资源；为三七种植上合理使用化学农药提供指导。

三七为我国特有的名贵中药，但严重病虫害需大量地使用农药而致农残超标，污染环境及破坏土壤微生态平衡。放线菌在土壤微生物生态和三七健康生长过程中起着重要作用，在本项目经费的支持下，我们通过免培养（高通量测序）的方法对五种农药处理三七土壤中放线菌群落结构和功能基因的组成进行分析，弄清了施加五种农药对三七土壤放线菌群落和功能的影响；从三七土壤分离得到1000 余株放线菌，筛选出70多株具有拮抗三七根腐病原菌活性的菌株，从活性菌株中获得3个放线菌新物种，已生效发表2个；从2株链霉菌和1株拟无枝菌酸菌中分离得到7个具有抑制三七根腐病原真菌活性的新化合物；发表SCI论文6篇，培养硕士生4名。这些研究成果为开发防治三七病害的生防放线菌剂及生物农药提供菌种资源；为三七种植上合理使用化学农药提供指导。