Flower structure, anatomy, and sexuality of Chrysophyllum gonocarpum (Sapotaceae).

The Sapotaceae are a significant component of the humid forests of the Neotropics and have many species of economic interest. Chrysophyllum gonocarpum is one of them and its edible fruits have currently acquired a high commercial value. Since there are no studies that cover its floral anatomy and elucidate its sexual system, the objective of the present study is to describe these aspects based on field observations and a detailed anatomical analysis of their flowers.

Anther structure and pollen development in species of Rubiaceae and anatomical evidence of pathway to morphological dioecy.

we conducted anatomical analysis of anthers with the aim to establish the differences in the development pattern of microsporophytes and microgametophytes between perfect and imperfect flowers in the tribe Gardenieae (Rubiaceae). The species studied were: Tocoyena formosa (monoecious with perfect flowers), Cordiera concolor, Genipa americana, Randia calycina, and Randia heteromera (dioecious with imperfect flowers). Flowers in successive stages of development were collected and fixed.

Anatomy and development of the edible fruits of Cordiera concolor (Rubiaceae).

A comprehensive study on the fruit anatomy and development of Cordiera concolor was carried out to establish the origin of the gelatinous tissue surrounding the seeds at maturity. Cordiera currently belongs to tribe Cordiereae, forming part of the species-rich lineage called Gardenieae complex. Most genera of Gardenieae complex has many-seeded fleshy fruits, with seeds usually imbedded in a pulp, which historically was considered of a placental nature.

Embryology of some flowers of the Gardenieae complex (Rubiaceae).

Different breeding systems occur in the Gardenieae complex (Rubiaceae), from homoecy to dioecy which is present in two tribes, Gardenieae and Cordiereae. As part of a broad project focused on the reproductive anatomy of the species of these two tribes, we described the structural and functional differences of the gynoecium in the different floral morphs and determined the degree of gynoecium development in the staminate flowers. We conducted a comparative anatomical study focused on the gynoecium of one homoecious species (Tocoyena formosa, with perfect flowers) and three dioecious species (Genipa americana, Randia calycina, and Randia heteromera) of Gardenieae and one dioecious species (Cordiera concolor) of Cordiereae.

Androecium anatomy of Isertia laevis, a polysporangiate species of Rubiaceae.

In this study, we performed an anatomical analysis of the polysporangiate anthers and the development of pollen in Isertia laevis (Rubiaceae) with the aim to elucidate the internal structure of these atypical anthers. For this purpose, flowers in successive stages of development were dissected and the anthers were processed for conventional anatomical analysis. The material was examined using light microscopy and scanning electron microscopy.