三七土壤及内生放线菌的多样性与动态特征

Radix notoginseng [Sanqi, Panax notogiseng (Burk.) F.H.Chen] and relative preparations have been widely used in clinical, however the quality has been affected by replanting obstacle, chemical pesicides and fertilizers. Soil and endophytic actinobacteria are closely relative to the live conditions and the growth of P. notoginseng. Little information in the relationship between P. notoginseng and actinobacteria is known. In this proposal, we will investigate diversity, community structure of soil actinobacteria, endophytic actinobacteria, and their dynamics with seasons. Main research will be focus on: a) improving isoaltion methods to collect the soil and endophytic actinobacterial isolates; b) investigating the community structures and dynamics of soil and endophytic actinobacteria associated with P. notoginseng by culture-dependent and culture-independent approaches; c) screening antagonistic actinobacterial strains against the pathogens of P. notoginseng; d) studying the possible factors affecting actinobacterial diversity. For the specific aims, we try to obtain 300-500 actinbacterial strains, interpret the actinobacterial community structure, select some antagonists to plant diseases, publish 3-5 SCI articles. We hope to interpret the relationship between the diversity, community structure of actinobacteria and the plant growth and diseases. Our finds will supply foundations for the green planting of P. notoginseng.

三七及其制剂在临床上广泛使用，但三七的质量受到了农药、化肥污染及连作障碍等因素的严重影响。土壤放线菌和植物内生放线菌与三七的生长和生存环境存在着密不可分的关系，但这方面的研究尚缺。本项目将在前期的工作基础上，深入研究三七土壤及内生放线菌的多样性、群落结构及其随时间变化的规律。主要研究内容：1、完善分离方法，建立三七种植土壤及植物内生放线菌的资源库；2、利用纯培养和免培养的方法，研究三七的土壤和植物内生放线菌的群落结构及其随时间变化；3、筛选具有拮抗三七病害的活性放线菌菌株4、初步探索影响土壤和内生放线菌多样性及群落结构的可能影响因素。通过本项目研究，将获得300－500株放线菌菌株、解释放线菌多样性及群落结构、筛选出5－10株具有抗三七病害的活性菌株、发表SCI论文3－5篇。最终希望揭示土壤及内生放线菌的多样性及结构组成与三七植物生长与病害发生等关系，为绿色三七的种植提供基础。

三七及其制剂在临床上广泛使用，但三七的质量受到了农药、化肥污染及连作障碍等因素的严重影响。在本项目经费的支持下，我们通过免培养（高通量测序）的方法对不同年限及不同生长期三七土壤和内生放线菌多样性和群落组成进行分析，弄清了三七连作过程中的放线菌群落结构组成随连作年限和季节的变化规律，推测地域不同和肥料、农药使用差别可能影响三七土壤中放线菌群落结构；从三七土壤和根内分离得到1300余株放线菌，筛选出100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5个放线菌新物种，已生效发表2个；采用活性追踪方法，从一株链霉菌中分离得到3个吩嗪类新化合物；通过活性菌株田间定殖能力及其对三七病原菌尖镰孢抑制作用评估，目前获得了1株具有防治三七病害的生防菌株；发表SCI论文3篇，培养硕士生6名。这些研究成果为三七的合理种植与管理提供指导，同时为开发适于三七种植的放线菌肥料及微生物农药提供菌种资源。