Caracterização morfológica de embriões por imagens de raios x e relação com a massa e a qualidade fisiológica de sementes de Tecoma stans L. Juss. ex Kunth (Bignoniaceae)

Abstract

The images obtained by X-ray have been used to analyze seed quality since the 1950s and recently have gained prominence because it is a fast, accurate and non-destructive method. Thus the objective of this study was to evaluate the morphological characteristics of the embryo structure of Tecoma stans L. Juss. ex Kunth seeds with different mass, making use of X-ray images and correlating these images with seed germination and seedling morphological aspects. To obtain embryo images, seven classes of seed mass were used with thirty seeds in each class that were X-rayed. The embryos of each class of seed mass were separated according to their morphological characteristics in four categories (embryos without defect, embryos with small defect, deformed embryos and seeds without embryo). The seeds were placed to germinate (radicle protrusion) and after ten days the normal seedling number was observed in each class of seed mass. Most of the seeds in the 1st and 2nd classes of seed mass, that were lighter, had seeds with embryo deformity or seeds without embryo. Almost all or all the seeds with the highest mass (classes 3rd to 7th) had seeds with embryos without defect. Almost all the seeds with embryos without defect germinated, buts not all gave origin to normal seedlings.