四株昭通乌天麻共生蜜环菌的生理生化特征及其分子鉴定

目的 对4株昭通乌天麻（Gastrodia elata）共生蜜环菌（Armillaria mella）的生理生化活性进行研究，并鉴定其分类地位。方法 通过测定不同碳源和氮源对蜜环菌生长的影响以及胞外酶活性，掌握该蜜环菌生理生化特性，再结合rDNA-IGS序列分析方法进行鉴定。结果 不同蜜环菌需要不同的碳源、氮源；3种胞外酶活性中木聚糖酶活性最大，其次是羧甲基纤维素酶，漆酶活性最小；供试蜜环菌与云南、贵州地区天麻共生蜜环菌以及猪苓共生蜜环菌的亲缘关系比较远。结论 蜜环菌能否作为天麻共生菌与其分类地位无关。

The physiological and biochemical properties and molecular identification of Armillaria mella in symbiosis with Gastrodia elata from Zhaotong

Abstract: Objective To explore the physiological and biochemical activities of 4 strains of Armillaria mella in symbiosis with Zhaotong Gastrodia elata, and its taxonomic status. Methods The influence of different carbon and nitrogen sources on the growth of Armillaria mella as well as the activities of its extracellular enzymes were tested. Identification of the bacteria was performed by using rDNA-IGS sequencing method. Results The optimal carbon source and nitrogen source were different for these strains of Armillaria mella. The activity of xylanase was the highest among three extracellular enzymes, followed by carboxymethyl cellulase, and that of laccase was the lowest. The tested strains of Armillaria mella did not show close genetic relationships with the Armillaria mella strains in symbiosis with Gastrodia elata in Yunnan and Guizhou regions, neither the Armillaria mella strains in symbiosis with Polyporus umbellatus. Conclusion The taxonomic status of Armillaria mella can not be used to confirm its symbiotic relationship with Gastrodia elata.