第58届Intel ISEF中国参赛项目：蘑菇的一种新奇菌丝附属结构

云南省昆明市云南师范大学附属中学  高 二  方淋

学科：微生物学

    研究发现毛头鬼伞对线虫有较好的致死作用，而致死功能与其菌丝体上产生的一种新奇附属结构密切相关。通过本项研究，深入认识附属结构，为线虫生防奠定基础。采用光学和扫描电镜观察，发现新奇附属结构是由许多触手般的管状结构组成，命名为刺状小球，系担子菌附属结构中尚未报道过的一个新类群。功能研究发现，刺状小球通过管状突起刺伤线虫体壁，造成线虫内容物外泄，最终杀死线虫。室内条件下，刺状小球10分钟对线虫的致死率达95.5%，如何将刺状小球应用于田间线虫生防？刺状小球对线虫是单纯的机械作用还是有其它因素参与？均有待于进一步研究。

Magic of Mushroom, Coprinus Comatus Damages Nematode with Spiny Balls and Produces Toxins to Immobilize Nematode

Microbiology

Can you image a mushroom can attack nematode? But that is true. Earlier we reported a unique fungal structure called spiny ball on vegetative hyphae of Coprinus comatus contributed to immobilize nematodes. In this study, we showed that purified spiny balls immobilize and kill free-living nematode Panagrellus redivivus Goodey in high efficiency. Scanning electron microscopy studies illustrated that the spiny structure damaged the nematode cuticle, suggesting the presence of mechanical force in the process of immobilizing the nematode. Severe injury on nematode cuticle caused leakage of inner material of the nematode. When these structures were ground with liquid nitrogen, the efficacy against nematodes was lost, indicating the shape and the complete structure of the spiny ball are indispensable for its function. Moreover, extracting the structure with organic solvents never lowered their activity against P. redivivus, and the extracts showed no obvious effect on the nematode. We also investigated whether C. comatus was able to produce toxins which would aid in the immobilization of nematodes. Here we presented the identification of 7 toxins isolated from C. comatus which could immobilize the nematodes P. redivivus and Meloidogyne incognita (Kofoid & White) Chitwood. The structure of the toxins was identified with NMR, MS, IR, and UV spectrum data. Two compounds were revealed as novel compounds. The toxins found in C. comatus are O-containing heterocyclic compounds.