Anatomy of stems, leaves, roots and the embryo of Garcinia brasiliensis Mart. - Clusiaceae

Abstract

Studies concerning the structure of plant embryos are very important in different areas of study such as plant systematics and evolution or the handling of native species. This work aims at evaluating the anatomy of the embryo and vegetative organs of Garcinia brasiliensis in order contribute to taxonomical, ecological, handling studies of this species. Some seeds were stored for anatomical analysis of the embryo and some were germinated to obtain young plants for anatomical analysis of the vegetative organs. Plants were cultivated in growth chamber for 120 d. Seeds and young plants were both fixed in a solution of formaldehyde, acetic acid, and 70% ethanol and usual plant microtechnique methods were employed. Slides were photomicrographed and a quantitative analysis of tissues was performed using UTHSCSA-Imagetool software. Histochemical analysis was performed for the detection of starch, lipids, alkaloids, and phenolic compounds. The G. brasiliensis embryo has rudimentary cotyledons and the reserves are stored in the hypocotyl-radicle axis. Most of the reserves are starch grains, stored in ground meristem cells, which contain a few oleossomes and alkaloids in the cell walls. The young plant leaves show dorsiventral and hypostomatous properties, including a one-seriated epidermis and a thick cuticle. In the midrib vascular bundle, the phloem is organized around the xylem vessels. The primary stem has a one-seriated epidermis and angular collenchyma. Adventitious roots are polyarch and show a one-seriated epidermis and endodermis. The anatomy of embryos and young plants of G. brasiliensis is similar to that of other Clusiaceae species.