Floral developmental insights into two species of Erythrina (Fabaceae: Papilionoideae: Phaseoleae) pollinated by hummingbirds and passerines.

Erythrina is a Pantropical bird-pollinated genus of Fabaceae. Thus, its flowers are usually large, showy, red or yellowish, offering nectar as the principal resource. There are two main interaction systems with birds in Erythrina: in one, the inflorescences are erect and the flowers are horizontal, offering no landing platform; in the other, the inflorescences are horizontal and the flower parts are more exposed.

Floral Development of Rhamnaceae and Origin of Its Unique Floral Features.

Rhamnaceae flowers have a peculiar morphology, including keeled sepals, one stamen whorl closely related to the petals, and a broad perigynous hypanthium that supports a voluminous nectary. In the present investigation, we detailed the flower development of five Rhamnaceae species to understand the origin of such specific floral characteristics. Floral buds and flowers were processed for surface and histological analyses.

Heteromorphic stamens are differentially attractive in (Fabaceae).

The division of labour hypothesis between stamens has explained the evolution of divergent functions between dimorphic stamens in the same flower. However, little is known about whether the distinct type of stamens differs in attractiveness to pollinators. Therefore, we investigate whether the two types of stamens commonly found in have different visual and olfactory attractants.

Connective modifications and origin of stamen diversity in Melastomataceae.

The androecium of Melastomataceae presents notable modifications in its merosity, morphology between whorls and in prolonged connectives and appendages. We carried out a comparative study of six Melastomataceae species to shed light on the developmental processes that originate such stamen diversity. The development of stamens was studied using scanning electron microscopy and histological observations.

The ontogenetic bases for variation in ovary position in Melastomataceae.

Premise Of The Study: Although the ovary position is considered a stable character in angiosperms, Melastomataceae species have perigynous flowers in which the ovary varies from superior to inferior. Thus, we investigated the ontogenetic process involved in variation of the ovary position in Melastomataceae. We focused on histogenesis of the floral apex in search of developmental patterns for each type of ovary position.