Contributions to the embryology of Agave (Asparagaceae)

Abstract

The genus Agave belongs to the Asparagaceae family, and comprises about 290 species, mostly native to arid and semi-arid regions. Many species are cultivated for ornamental purposes or as a source of various raw materials, demonstrating a high capacity for vegetative propagation through the formation of bulbils. The few embryological studies with species of the genus showed interspecific variation in certain characters, such as the type of embryo sac development, and pointed to embryo sac malformation as one of the causes of low seed formation. In this project, the development of the anther and ovule of Agave species will be studied to better understand reproductive aspects and identify whether there are errors during sporogenesis that explain the low fertility and the significant investment in the formation of bulbils. For this purpose, flowers at different developmental stages will be anatomically analyzed through serial cross sections. The samples will be embedded in historesin and sectioned on a rotatory microtome. The sections will subsequently be stained and mounted on permanent slides with Entellan, which will be analyzed under light microscope. The results will be documented with images obtained using an image-capturing device coupled to a microscope and will be fundamental to support studies of reproductive biology, seed propagation and genetic improvement, given the economic importance of the species under investigation.