莲子草假隔链格孢菌2个特异致病毒素的基因鉴定及其作用机理研究

Alternanthera philoxeroides, commonly known as alligatorweed, has become one of the most serious invasive species in China. The study of host-specific and non-host-specific phytotoxins would facilitate the development of a commercial product. Previous studies showed that: Nimbya alternantherae has the putative host specific phytotoxin NaPKS1 and non-host specific phytotoxin NaPKS9, which might be the toxin vulculic acid previously discovered. NaPKS1 and NaPKS9 may play pathogenic roles at different stages, and furthermore the corresponding host response genes are quite different. On this basis, our project intends to clone and conduct heterologous expression of NaPKS1 and NaPKS9 to identify the gene products and their properties. We will also verify the relationship of the toxin and pathogenicity by gene knockout to identify the possible interaction mechanisms. Our study will provide useful information for managing alligatorweed, and insights into phytotoxins for biological control and phytopathology.

空心莲子草是我国杂草防治乃至有害生物治理的重点目标之一，传统防治方法难以奏效。对其生防真菌莲子草假隔链格孢菌的寄主专化性和非专化性毒素的研究将有利于开发新型的高效低毒药剂。前期研究表明：该菌具有潜在的寄主专化性毒素NaPKS1和非专化性毒素NaPKS9；其中NaPKS9可能是前期获得的vulculic acid；此外，NaPKS1和NaPKS9可能在不同阶段中发挥致病作用，且对应时间段的寄主反应基因有较大差异。在此基础上，本项目拟进一步对NaPKS1和NaPKS9进行基因克隆及异源真核表达，以确定基因产物及其专化性，拟进行基因敲除以验证该产物与致病的关系，找出可能的互作机理。为空心莲子草的防治提供切实可行的方法；并为植物病害的防治以及有害生物的防治提供参考。

空心莲子草是我国杂草防治乃至有害生物治理的重点目标之一，传统防治方法难以奏效。对其生防真菌莲子草假隔链格孢菌的致病相关基因的研究将有利于开发新型的高效低毒药剂。本研究测定了莲子草假隔链格孢菌NA2的全基因组序列，克隆获得NaPKS1,NaPKS9,g2057和g9900等四个致病相关基因，将其进行真核表达并纯化，对空心莲子草进行离体和活体接种，出现不同程度的致病作用。将NaPKS1和NaPKS9基因敲除后，菌株降低了致病力。本研究为空心莲子草的防治提供切实可行的方法；并为植物病害的防治以及有害生物的防治提供参考。