Artigo
Narrow Fungal Mycorrhizal Diversity in a Population of the Orchid Coppensia doniana
Registro en:
Biotropica. Malden: Wiley-blackwell, v. 44, n. 1, p. 114-122, 2012.
0006-3606
10.1111/j.1744-7429.2011.00769.x
WOS:000298944400015
Autor
Valadares, Rafael B. [UNESP]
Pereira, Marlon C.
Otero, Joel T.
Cardoso, Elke J. [UNESP]
Resumen
In nature, orchids are fully dependent on mycorrhizal fungi to germinate their seeds. These fungi can penetrate root cells and form pelotons, hyphal coils responsible for providing simple sugars for the orchid embryo. During the achlorophyllous seedling stage, orchids depend on fungi; and some species remain dependent through life, while others establish photosynthesis but, to varying degrees, remain facultatively dependent or responsive to fungal colonization as adults. The aim of this study was to identify how many clades of fungi can establish mycorrhizal associations with Coppensia doniana, a widespread orchid in Campos do Jordao (Brazil) and to demonstrate how morphological features can be useful to group and identify these fungi. Plants were collected during the dry season of 2009 near Campos do Jordao State Park. Fungi were isolated by transferring root segments containing pelotons to media. Three main clades of fungi were formed by either qualitative or quantitative morphological data. We identified these fungi as two morphotypes of Ceratorhiza (anamorphic stage of Ceratobasidium) and one uninucleate Rhizoctonia. The internal transcribed spacer (ITS) sequencing data corroborated the morphological features showing the same three clades; all isolates showed a high similarity with Ceratobasidium ITS sequences in GenBank. Thus, it was possible to demonstrate a high affinity between this orchid species of Oncidiinae and Ceratobasidium. Morphological data associated with multivariate statistics proved to be a useful tool in multilevel taxonomy of these orchid-associated fungi. Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Sao Paulo State Univ, Dept Soil Sci, Coll Agr Luiz Queiroz ESALQ, Sao Paulo, Brazil Fed Univ Vicosa UFV, Biol Sci & Hlth Inst, Rio Paranaiba, Brazil Univ Nacl Colombia, Inst Estudios Ambientales, Dept Ciencias Biol, UNAL Palmira,Sede Palmira, Bogota, Colombia Sao Paulo State Univ, Dept Soil Sci, Coll Agr Luiz Queiroz ESALQ, Sao Paulo, Brazil