Aspectos morfoanatômicos de sementes e plântulas de Ochroma Lagopus Swartz - Malvaceae

Abstract

Ochroma lagopus Swartz (Malvaceae) is commonly known as pau-debalsa and occurs naturally from southern Mexico to Bolivia. In Brazil is common in the state of Amazonas. It is a tree species and its main importance is related to the use of their wood in the manufacturing of boats and rafts and with potential for use for reforestation in the region. The objective is describe and illustrate morfoanatomics aspects of seed of pau-de-balsa. The work began with the collection of fruit and trees in the Estação Experimental de Silvicultura Tropical, do Instituto Nacional de Pesquisas da Amazônia INPA, Manaus/AM. The study was conducted morphology of the Laboratório de Botânica Agroflorestal (LABAF) da Universidade Federal do Amazonas and anatomical analysis in laboratory anatomy, no Núcleo de Microscopia e Microanálise (NMM) and the Laboratory of Micorrhyzum / BIOAGRO da Universidade Federal de Viçosa (MG). Been made measurements of length, width, thickness and moisture content. The parameters were observed morphological external and internal seed for morphological description, the use of techniques for light microscopy, and scanning electron microscopy to characterize anatomical, and employee test histochemical with Sudan Red B, Nile Blue, Lugol, Floroglucine, Xilidine Pounceau, Astra Blue and Basic Fuchsin, Rutênio Red and Ferric chloride. Ochroma lagopus contains 8,8% of moisture content. The seed is estenospérmic, albuminose, axial invaginated plicate embryo, foliaceous cotyledons. The tegument is formed by cells expanded arranged in palisading. The endosperm and the embryo cells have thin walls with varying shape and size. In the histochemical analysis of the tegument the tests gave positive responses to polysaccharides, lignin and phenolic compounds and endosperm and the embryo to proteins, lipids and starch.