马铃薯内生炭角菌与马铃薯早疫病病原菌的化学相互作用研究

Potato early blight is one of serious diseases causing heavy reduction of potato production. Therefore, it is demanded to develop environment-friendly and specific agents to prevent potato from early blight. Endophytic Xylaria sp. from potato has selective inhibition on early blight pathogen Alternaria solani. Chemical research on Xylaria sp. resulted in the isolation and identification of 16 new cytochalasins (including one new skeleton) and 5 new lactones. In the co-culture experiment of Xylaria sp. and A. solani, they showed traits of chemcial interaction. Xylaria sp. was induced by A. solani to produce two types of unknown secondary metabolites, and increased the production of some metabolites. This project is planning to utilize technologies including MALDI-imaging-MS to investigate the chemical crosstalk between these two strains, in order to discover and obtain compounds active on A. solani. Afterwards, the anti potato early blight effect of Xylaria sp. and active compounds will be evaluated. This project aims to build the foundation to develop new anti potato early blight bio-control agent, and to enrich the knowledge on the relationship between endophytic fungi, host plant and pathogens.

马铃薯早疫病是普遍发生并造成马铃薯大量减产的主要病害之一。针对该病害开发环境友好和作用专一的农药是目前重要需求。Xylaria sp.是一株马铃薯内生炭角菌，对马铃薯早疫病病原菌茄链格孢具有选择性抑制作用。前期研究从Xylaria sp.发酵物中分离鉴定了16个新的细胞松弛素类化合物（包括一种新骨架）和5个新的内酯。Xylaria sp.与茄链格孢共培养时显示出明显的化学相互作用特征，能够被茄链格孢诱导产生两类未知的次生代谢产物，其他部分成分含量也发生了明显变化。本项目拟通过MALDI影像质谱等技术研究两株菌之间的化学交流，从中发现和分离鉴定抗茄链格孢活性小分子，并评估Xylaria sp.及其活性成分防治马铃薯早疫病的能力。为开发新的抗马铃薯早疫病的生物农药打下前期基础，并进一步丰富对植物内生真菌—病原菌—宿主植物之间化学相互作用的认识。

马铃薯早疫病是普遍发生并造成马铃薯大量减产的主要病害之一。针对该病害开发环境友好和作用专一的农药是目前重要需求。本项目前期发现马铃薯内生长柄炭角菌Xylaria longipes能够选择性抑制马铃薯早疫病病原菌茄链格孢具有选择性抑制作用，随后采用OSMAC策略和基因挖掘技术对对象菌的次生代谢产物进行了系统的研究，分离鉴定了100余个包括细胞松弛素、大环内酯、环肽在内的代谢产物，包括四种骨架新颖的细胞松弛素类化合物。项目对对象菌、病原菌和马铃薯进行了共培养、接种等研究，利用MALDI影像质谱技术和代谢组学分析发现了大环内酯类化合物可能参与了它们之间的化学交流。单体化合物的活性测试发现了细胞松弛素类化合物具有较强的逆转真菌耐药的作用。项目利用对象菌的生物制剂对马铃薯幼苗进行接种，发现其能够显著提升植株对病原菌的抵抗力。基于本项目目前已经发表了SCI论文8篇，培养了2名硕士研究生毕业，参与了2次学术交流汇报，并有一篇专利正在准备之中。