ANATOMY AND MORPHOLOGY OF BRAZIL NUT KERNELS AND SEEDLINGS

Abstract

The studies in plant propagation require basic knowledge about the seed and their transformation until seedlings formation. The knowledge of anatomic and morphologic characteristics of seeds and seedlings may contribute to the germination process understanding. The objective of this work was to describe anatomic and morphologic aspects of kernels and seedlings of brazil nut, characterizing the tissues responsible to the germinating structures differentiation. The kernels, before and 45 days after sowing, and seedling were removed from the seedbed and submmited to usual botanical techniques to make slides and to tissue analysis. The kernel or embryo of brazil nut is chiefly composed of parenquimatic tissues delimited by a meristematic ring. The tissues are covered by an epidermic layer and a lignified pellicle. The epicotyl and primary root appear with the diferentiation of pre-exintent meristematic tissues preferencially in the epycotil and radicular pole. The anatomic structure of embryo explain in part the slow germinative process in this tree species and are correlacted with the success of the dispersal process in natural condiction.