Bergero R, Perotto S, Girlanda M, Vidano G, Luppi A M
Dipartimento di Biologia Vegetale, University of Torino,Centro di Studio sulla Micologia del Terreno-CNR, Viale Mattioli 25, 10125-Torino, Italy.
Mol Ecol. 2000 Oct;9(10):1639-49. doi: 10.1046/j.1365-294x.2000.01059.x.
Mycorrhiza samples of neighbouring Quercus ilex and Erica arborea plants collected in a postcutting habitat were processed to see whether plants differing in mycorrhizal status harbour the same root endophytes. Three experiments were performed in parallel: (i) isolation, identification and molecular characterization of fungi from surface-sterilized roots of both plant species; (ii) re-inoculation of fungal isolates on axenic E. arborea and Q. ilex seedlings; (iii) direct inoculation of field-collected Q. ilex ectomycorrhizas onto E. arborea seedlings. About 70 and 150 fungal isolates were obtained from roots of Q. ilex and E. arborea, respectively. Among them, Oidiodendron species and five cultural morphotypes of sterile isolates formed typical ericoid mycorrhizas on E. arborea in vitro. Fungi with such mycorrhizal ability were derived from both host plants. Isolates belonging to one of these morphotypes (sd9) also exhibited an unusual pattern of colonization, with an additional extracellular hyphal net. Ericoid mycorrhizas were also readily obtained by direct inoculation of E. arborea seedlings with Q. ilex ectomycorrhizal tips. Polymerase chain-restriction fragment length polymorphism and random amplified polymorphic DNA analyses of the shared sterile morphotypes demonstrate, in the case of sd9, the occurrence of the same genet on the two host plants. These results indicate that ericoid mycorrhizal fungi associate with ectomycorrhizal roots, and the ecological significance of this finding is discussed.
对在采伐后栖息地采集的邻近冬青栎和树状欧石楠植物的菌根样本进行处理，以观察菌根状态不同的植物是否含有相同的根内生菌。同时进行了三个实验：(i) 从两种植物表面消毒的根中分离、鉴定和分子表征真菌；(ii) 将真菌分离物重新接种到无菌的树状欧石楠和冬青栎幼苗上；(iii) 将田间采集的冬青栎外生菌根直接接种到树状欧石楠幼苗上。分别从冬青栎和树状欧石楠的根中获得了约70个和150个真菌分离物。其中，奥氏多孢菌属物种和五种无菌分离物的培养形态型在体外对树状欧石楠形成了典型的石楠类菌根。具有这种菌根能力的真菌来自两种寄主植物。属于这些形态型之一（sd9）的分离物也表现出一种不寻常的定殖模式，带有额外的细胞外菌丝网。通过将冬青栎外生菌根尖端直接接种到树状欧石楠幼苗上，也很容易获得石楠类菌根。对共享的无菌形态型进行聚合酶链反应-限制性片段长度多态性和随机扩增多态性DNA分析表明，在sd9的情况下，两种寄主植物上存在相同的基因。这些结果表明石楠类菌根真菌与外生菌根根相关联，并讨论了这一发现的生态意义。
