Desenvolvimento do fruto de Caryocar brasiliense e sua importância na sistemática e evolução de Malpighiales

Abstract

The features of the fruit are of great importance in the Caryocar systematics, including giving the name of the genus which is derived from the Greek Karyon, which means nut and the Latin Caro refer to the flesh, referring to its drupes. Despite its importance, the fruit of Caryocar is poorly known, and the origin of its layers was not appropriately studied. Thus, as (i) studies based on molecular characters have been insufficient to suggest hypotheses about Caryocaraceae kinship relations. Moreover, that (ii) the reproductive organs of the order Malpighiales are unknown or poorly known. Besides that (iii) your knowledge may be relevant to clarifying kinship relations in the order. The present work realized a more detailed study of the Caryocaraceae fruit, describing the development of the Caryocar brasiliense pericarp and detailing the origin of its layers. For this, anthesis, post-anthesis flowers, and fruits were processed according to usual techniques of cut and coloring on the histological resin. Our results showed that Caryocar has a large number of vascular bundle beyond the standard found for angiosperms with one dorsal vascular bundle and two ventral vascular bundles for each carpel. The atypical ovary vascularization found in Caryocaraceae is also found in Putranjivaceae and suggests an approximation of the two families. Concerning the fruit, the Caryocar brasiliense pyrene comes from the mesocarp and not from the endocarp, as described previously. Caryocar brasiliense showed some similarities to Malpighiaceae drupes and schizocarps. Our results, too, suggest that fruit development may help solve Malpighiales relations, an order of such a complex relation.