Anatomia caulinar de espécies epífitas de Cactaceae, subfamília Cactoideae

Abstract

Este estudo teve o objetivo de caracterizar anatomicamente o caule de sete espécies epífitas da família Cactaceae: Epiphyllum phyllanthus, Hatiora salicornioides, Lepismium cruciforme, L. warmingianum, Rhipsalis baccifera, R. cereuscula e R. sulcata, ocorrentes em um fragmento de Floresta Estacional Semidecidual do município de Maringá, noroeste do Paraná. A maioria apresentou caule recoberto por cutícula espessa, por vezes com uma camada epicuticular adjacente. Os estômatos são do tipo paralelocítico, freqüentemente localizados em depressões da epiderme. Subjacentes, estão de 1 a 3 estratos de hipoderme colenquimática e uma grande proporção de tecido cortical, contendo células mucilaginosas e idioblastos cristalíferos. O cilindro central tem os feixes vasculares orientados concentricamente, sempre com calota de fibras no pólo floemático, encerrando uma medula que pode ser ou não lignificada. Grãos de amido e substâncias lipídicas são as principais reservas destas plantas.

Morpho-anatomical variations during stem development in some epiphytic Cactaceae1

“…Although the authors cited their analysis of adult and young individuals, they did not describe any variations of these features during plant development. However, in the present study, Hatiora salicornioides always shows epidermal cells with wavy anticlinal walls in both primary and terminal stem segments, not square, as described by Dettke and Milaneze-Gutierre (2008). These results reveal that this feature is variable in some species and must therefore be identified by developmental studies in different populations.…”

“…Dettke and Milaneze-Gutierre (2008) described the hypodermis in seven epiphyte species of Cactaceae, including Hatiora salicornioides and Epiphyllum phyllanthus, but cited the non-collenchymatous thin-walled cells only in E. phyllanthus. According to Dettke and Milaneze-Gutierre (2008), the other species, including H. salicornioides, have annular thickness of the primary cell walls in more developed stem regions, whose observed in Rhipsalis floccosa (Fig. 3a, arrowhead).…”

“…Anatomical characters have been informative taxonomically in epiphyte species of Cactaceae (Terrazas and Arias 2003, Calvente et al 2008, Dettke and Milaneze-Gutierre 2008 such as the epidermis in surface view and transverse section, occurrence of collenchymatous hypodermis, cap fibers in the phloematic region or a sclerenchyma ring around the stele, and, finally, organization of the secondary xylem. However, few studies have examined different stages of development.…”

Structural features of species of Asteraceae that arouse discussions about adaptation to seasonally dry environments of the Neotropics

“…In addition to this feature, the aquifer cells in the palisade parenchyma of P. purpurascens, which also occur in W. trichostephia, and the aquifer potential of the hypodermis of P. gardneri, have been poorly studied in plants of different Neotropical arid and semi-arid environments. These structures, being associated with water storage and transport, promote anatomical differences resulting from physiological adaptations at different levels, in addition to maintaining water potential in leaves and acting on water balance and photosynthesis (Fahn & Cutler 1992;Dettke & Milaneze-Gutierre 2008;Rossatto & Kolb 2010).…”

Morfoanatomia vegetativa de Opuntia brasiliensis (Willd) Haw / Vegetative morphology and anatomy of Opuntia brasiliensis (Willd) Haw

“…Os estudos anatômicos com Cactaceae buscavam inicialmente identificar as relações estruturais com o metabolismo fotossintético MAUSETH;PLEMONS-RODRIGUEZ, 1998), porém pesquisas de caracterização morfológica e anatômica têm sido realizadas com sucesso na descrição e taxonomia das espécies (ROCHA; AGRA, 2002;HAYASHI, 2005;CALVENTE et al, 2008;DETTKE;MILANESE-GUTIERRE, 2008;FUENTES-PÉREZ;FAIGÓN et al, 2011). Entretanto, a maioria dos estudos enfatiza a comparação de órgãos de diferentes espécies, sem descrever a estrutura completa do vegetal.…”