Avaliação de caracteres anatômicos do eixo da inflorescência de representantes das seções neotropicais de Bulbophyllum Thouars (Orchidaceae, Asparagales)

• Autor(a) principal: Araújo, Giselle Bezerra de [UNESP]
• Data de Publicação: 2017
• Tipo de documento: Trabalho de conclusão de curso
• Idioma: por
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/156427; http://www.athena.biblioteca.unesp.br/exlibris/bd/capelo/2018-04-26/000897690.pdf
• topic: Anatomia vegetal; Orquídea; Epiderme

Bulbophyllum (Orchidaceae) is a genus with pantropical distribution and is considered the second largest of the angiosperms. The morphological and anatomical studies of its reproductive and vegetative organs are still incipient, but they already demonstrate applicability of the character set in both infrageneric and specific delimitation. Based on this context, the objective of the present study was to verify anatomical characters of the inflorescence axis (scape and rachis) of representatives of the six neotropical sections of Bulbophyllum, looking for the evaluation of anatomical evidences that can be used in the delimitation of the taxa studied. We sampled one species of B. sect. Bulbophyllaria, seven species of B. sect. Didactyle, one species of B. sect. Furvescens, six species of B. sect. Micranthae, seven species of B. sect. Napelli, and three species of B. sect. Xiphizusa; as outgroup, for comparison, B. falcatum, B. lobbii and Dendrobium kingianum were analyzed. For the analysis of the anatomical characters, usual techniques of light microscopy were used, followed by photodocumentation and micrometric scale projection. All species studied of Bulbophyllum present floral scape and rachis with great similarity and homogeneity in their anatomical characters, such as: uniseriate epidermis; stomata with suprastomatic chamber; secretory trichomes located in depression in the epidermis; idioblasts with helical thickening or with raphides, present in both the cortex and the medulla; continuous and uniseriate endodermis; atactostelic vascular cylinder formed by collateral vascular bundles. Our analysis also allowed us to identify two species with exclusive anatomical characteristics, among the twenty three species belonging to the six neotropical sections of the genus here analysed: B. rupicolum (B. sect. Micranthae), which has scapes with papillose epidermis, and B. weddellii (B. sect. Didactyle), which has mixed idioblasts (with helical...