Morfoanatomia e tecnologia para produção de mudas e indicação de uso da madeira de Pseudobombax munguba Dungad (Malvaceae – Bombacoideae).

Abstract

Pseudobombax munguba (Mart.) Dugand., is a deciduous tree that can exceed 40 m in height, predominant in the floodplain forests of the Amazon, the paina produced by the fruits and the bark of the stem are traditionally required in the manufacture of upholstery and handcrafted utensils , respectively. The present work aims to describe and analyze the morphometry of fruits and seeds, post-seminal development, as well as the sensitivity of the seeds in the desiccation process; the anatomical characteristics of the secondary xylem and the basic density of the species in a várzea forest fragment of the Federal Rural University of Amazônia, in the municipality of Belém, Pará. In the fruits and seeds, external and internal details were observed, according to the specialized literature ; the biometry of the fruits recorded in cm and the seeds in mm; for post-seminal development, 300 seeds were seeded in plastic containers containing sand and tanned sawdust (1: 1). In the control (100 fresh seeds) and in the seeds 200 seeds desiccated for 24 and 48 hours, the percentage of germination, normal and abnormal seedlings, dead seeds, average germination time, and germination days were quantified . For the anatomy of the wood, the macro and microscopic characterization of the cellular elements, the verification of substances by the cytochemical analysis, basic density by the hydrostatic balance method; in the qualification of wood for paper or energy production, the coefficients of stiffness and flexibility, wall fiber fraction, Runkel index, and percentages of fiber, vessels, axial parenchyma and rays were evaluated. P. munguba presents septic fruit capsule, length and diameter ranged from 15.74 to 33.8 cm; 7.09 to 9.9 cm, respectively. Seeds pyriform, with length and diameter of 3.6 to 5.2 mm, 3 to 4 mm, respectively. Epigene-foliaceous germination, occurring in three days after sowing, with significant increase in hypocotyl and epicotyl length as a function of time. The young plant with palmaticomposed metaphyls was observed 180 days after sowing. The reduction of water content from 7.4% to 4.7% did not statistically affect the percentage of germination, showing that the seeds are dispersed with low water content. As for wood, the species has porosity in semiporous rings, large and solitary vessels (47.5%), diffuse apotracheal parenchyma (23.4%) in aggregates; non-stratified rays (25.4%); fibers (3.7%) long, uncrowded thin-walled fibers; low basic density (0.18 g.cm-3); coefficient of stiffness of 62.7% and 77% of flexibility, 37.3% of wall fraction and 0.67 of Runkel index. These results show that the species presents a rapid establishment as a young plant, and its seeds are susceptible to storage; and wood is promising as an alternative source of raw material for the production of paper.