新疆野果林苹果腐烂病病原菌鉴定及药用植物内生细菌对其抑菌效果

【背景】药用植物内生细菌能产生与寄主植物相同或相似的化合物及一些新的次级代谢产物等，具有促进宿主植物生长、抵抗病虫害、降解有毒有害化合物等作用。【目的】进一步提高苹果腐烂病生物防治的效率，丰富新疆药用植物内生细菌拮抗功能菌株的资源库。【方法】从新疆伊犁新源县和塔城额敏县野果林中采集带腐烂病病斑的果树枝条，分离鉴定苹果腐烂病病原菌，并采用平板对峙法从药用植物内生细菌中筛选对苹果腐烂病具有抑制作用的拮抗菌株。【结果】从两地共分离获得234株分离株，筛选鉴定出25株Valsa malicola和2株Valsa mali；同时，筛选出92株具有抑菌效果的内生细菌菌株，其中70株来自甘草植物内生细菌。【结论】药用植物甘草中富含较为丰富的抗苹果腐烂病病原菌的微生物菌株资源。本研究在新疆野果林苹果腐烂病的生物防治及药用植物内生细菌的开发利用等方面具有重要意义。

Identification of pathogens causing apple Valsa canker in Xinjiang wild apple forests and antifungal effect of endophytic bacteria from medicinal plants on the pathogens

Background] Endophytic bacteria of medicinal plants can produce the same or similar compounds as host plants and new secondary metabolites, which can promote the growth of the host, resist diseases and insect pests, and degrade toxic and harmful compounds. Objective] To further improve the biocontrol efficiency of apple Valsa canker, and enrich the resource pool of antagonistic strains of endophytic bacteria from medicinal plants in Xinjiang. Methods] The pathogens of apple Valsa canker were isolated and identified from the branches with disease spots of the apple plants in the wild apple forests of Xinyuan County (Yili area) and Emin County (Tacheng area) in Xinjiang. The endophytic bacteria of medicinal plants, which had the ability against the pathogen of apple canker, were screened by plate confrontation method. Results] A total of 234 strains of pathogenic fungi were isolated from Xinyuan county and Emin county, including 25 strains of Valsa malicola and 2 strains of V. mali. In addition, 92 strains of endophytic bacteria with antifungal effect were screened out, among which 70 strains were from Glycyrrhiza uralensis. Conclusion] The medicinal plant G. uralensis is rich in microbial resources against apple Valsa canker. This study is of great significance for the biocontrol of apple Valsa canker in Xinjiang wild apple forests and the development and utilization of endophytic bacteria in medicinal plants.