基于根表真菌群落与病原菌鉴定探究‘宁杞 5 号’枸杞 根腐病的发生机制.

【Objective】 This paper is to compare the composition of rhizoplane fungal communities in susceptible strain ‘Ningqi-5’ between the healthy and diseased plants in the two planting areas (QXBZ and QTBZ), as well as the isolated rot root fungi. It is also to clarify the pathogens causing root rot disease in ‘Ningqi-5’, and to explore the reasons for the root rot disease in ‘Ningqi-5’.【Method】High-throughput technology was applied to investigate the compositional characteristics of the rhizoplane fungal community. Tissue isolation method was to isolate the rot-root fungi the decayed roots of Lycium barbarum. They were taxonomically identified based on the morphological characteristics and the sequences of ITS and EF-1α gene fragments. The pathogenicity bythe rotten-root fungi was verified based on Koch's law.【Result】 The root rhizoplane fungal community composition differed significantly between the healthy and diseased plants of ‘Ningqi-5’ in both planting areas, showing the increase in relative abundance of Fusarium and decrease in relative abundance of Mortierella in the diseased plants, accompanying with the increase of unknown taxa like Fusicolla and Pseudogymnoascus. While the fungal community structure on the rhizoplane of the healthy plants in both planting areas tended to be consistent. The 36 strains isolated from the rotten rot of QXBZ were classified as Fusarium oxysporum, F. solani, Earliella scabrosa, Rhizoctonia solani, and Penicillium pimiteouiense. The 29 strains isolated from the rotten rot of QTBZ were classified as F. oxysporum, F. solani, E. scabrosa, Clonostachys rosea, P. pimiteouiense, F. andiyazi and Acremonium persicinum. Isolation frequency of F. solani was the highest in both planting areas, followed by F. oxysporum. Based on the artificial infection test, F. solani, F. oxysporum, R. solani, and F. andiyazi were identified as the pathogens of ‘Ningqi-5’ root rot disease, among which F. andiyazi was a newly discovered pathogen of L. barbarum root rot.【Conclusion】In this study, it is clarified that the occurrence of ‘Ningqi-5’ root rot disease is mainly closely related to the changes in the structure of the root rhizoplane fungal community and pathogens. F. solani, F. oxysporum, F. andiyazi, and R. Solani are the pathogens of ‘Ningqi-5’ root rot disease. [ABSTRACT FROM AUTHOR]