Anatomia metodologia Arruda

Revista Brasil. Bot., V.28, n.3, p.589-601, jul.-set. 2005

Anatomia dos órgãos vegetativos de Cactaceae da caatinga pernambucana1
EMILIA ARRUDA2,4, GLADYS FLÁVIA MELO-DE-PINNA2 e MARCCUS ALVES3
(recebido: 4 de março de 2004; aceito: 25 de agosto de 2005)

ABSTRACT – (Anatomy of the vegetative organs of Cactaceae of the caatinga from Pernambuco). Root and cladode transections of five species of Cactaceae from a “caatinga” of Pernambuco (Harrisia adscendens (Gürke) Britton & Rose; Melocactus × horridus Wedermann; M. zenhtneri (Britton & Rose) Luetzelb.; Tacinga inamoena (Schumann) Taylor & Stuppy, and T. palmadora
(Britton & Rose) Taylor & Stuppy), were analyzed to verify diagnostic and adaptative features. The sections were stained with safranin and astrablue and mounted in glycerine. The surveys did not show great differences in the roots inner structure among studied species. In the secondary xylem of the roots broad pericyclic rays occur, representing an important adaptative character in xerophytes. The cladodes present the following diagnostic and adaptative features: type of spines; type and position of stomata; hypodermis structure; presence of crystals in epidermis and hypodermis; type and position of mucilaginous structures; general aspects of the vascular system; occurrence of cortical and medular vascular bundles; and presence of storage parenchyma.
The results of this work show that the studied species are typical cacti presenting anatomical features, which can be responsible for the success of these plants in adverse environments as the “caatinga”.
Key words - anatomy, caatinga, Cactaceae, taxonomy
RESUMO – (Anatomia dos órgãos vegetativos de Cactaceae da caatinga pernambucana). Secções de raízes e cladódios de cinco espécies de Cactaceae ocorrentes em uma região de caatinga de Pernambuco (Harrisia adscendens (Gürke) Britton &
Rose; Melocactus × horridus Wedermann Notizbl.; M. zenhtneri (Britton & Rose) Luetzelb.; Tacinga inamoena (Schumann)
Taylor &