Anatomia foliar e análise morfométrica das fibras de Astrocaryum murumuru var. murumuru Mart. (Arecaceae).

Abstract

The objective of this work was to study the foliar anatomy and analyze morphometically the leaf fibers of Astrocaryum murumuni var. murwnuru Mart. (Arecaceae) in order to better understand the leaf structure of this species. The data generated by this investigation will be useful to taxonomic, ecological, and physiological studies involving this species and will lay the groundwork for future physical-mechanical analyses of its leaf fibers. The plant material used in this study was collected ffom the Combu Island, Belém municipality, Pará. Standard plant anatomical techniques were utilized, the fibers were measured digitally, and the data analyzed statistically using Biostat 3.0. The leaves of .4. murumuni are characterized by a hypostomatic lamina with subepidennal tetracitic stomata. The outer tissue is comprised of a unistratified epideiTnis overlying a hypodennal layer. The epicutical wax is thick and trichomes are filiform with persistent bases. The mesophyll is dorsiventral, within which are dispersed vascular bundles and fíber bundles, the latter enclosed by hat-shaped silica-bodies, which are also associated with the vascular bundles and the abaxially prominent main vein. Neighboring the midrid are inflated expansion cells. The rachis and petiole have similar anatomical organization. The epidermis is papillose and within the parenchyma are dispersed numerous vascular bundles, the marginal ones being completely enclosed within a fíbrous sheath. The fibers are translucent, rarely undulate, and are thick to very thick. Fibers differed in size at the 5% levei according to the Kruskall Wallis test and have morphometric characteristics favorable to the production of paper.