Sebacinales form ectendomycorrhizas with Cavendishia nobilis, a member of the Andean clade of Ericaceae, in the mountain rain forest of southern Ecuador
Sebacinales form ectendomycorrhizas with Cavendishia nobilis, a member of the Andean clade of Ericaceae, in the mountain rain forest of southern Ecuador
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DOI：
10.1111/j.1469-8137.2005.01583.x
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发表时间：
2006-01-01
期刊：
影响因子：
9.4
通讯作者：
Kottke, I
中科院分区：
文献类型：
--
作者：
Setaro, S;Weiss, M;Kottke, I
新铁杉Cavendishianobilis var.头状菌是杜鹃花科特有的一种半附生植物，生长在厄瓜多尔南部的热带山地雨林中。在海拔1850~2300m之间采集了20个个体的菌根。用透射电子显微镜详细研究了共生关系，并基于核糖体大亚基编码的核rDNA(NucLSU)进行了系统发育分析。显微镜和超微结构研究表明，同一真菌的膨胀菌丝形成了菌丝鞘，细菌丝穿透细胞间，皮层细胞定植。这些结构是由膜菌和子囊菌形成的。分子系统发育分析共鉴定出七类菌根真菌，分别属于塞巴菌目。这是首次在蛇床亚科中获得外生菌根的证据。子囊菌nucLSU序列属于乳酸菌的成员。黄曲霉的外生菌根是迄今为止未被描述的外生菌根中的一个特殊的菌根亚类。我们提出了一个术语‘洞穴状菌根’。这个亚类很可能是杜鹃花科安第斯支系特有的。
Cavendishia nobilis var. capitata is an endemic member of the Ericaceae growing as a hemiepiphyte in the tropical mountain rain forest of southern Ecuador.Mycorrhizas were collected from 20 individuals along an altitudinal gradient between 1850 and 2300 m. Transmission electron microscopy was used to study the symbiotic association in detail, and phylogenetic analyses based on nuclear rDNA coding for the ribosomal large subunit (nucLSU) were carried out to identify the associated mycorrhizal fungi.Microscopic and ultrastructural investigations showed the formation of a hyphal sheath, intercellular penetration of fine hyphae and colonization of the cortical cells by swollen hyphae of the same fungus. These structures were formed by hymenomycetes and ascomycetes. Molecular phylogenetic analysis detected seven groups of mycorrhizal fungi belonging to the Sebacinales. This is the first study to obtain evidence of ectendomycorrhizas in the Vaccinioideae. The ascomycetous nucLSU sequences belonged to members of the Leotiomycetes.The ectendomycorrhiza of C. nobilis with Sebacinales is discussed as a specific, hitherto undescribed mycorrhizal subcategory of ectomycorrhizas. We propose the term 'cavendishioid mycorrhiza'. This subcategory is most likely specific for the Andean clade of Ericaceae.