Paulino Juliana Villela, Prenner Gerhard, Mansano Vidal Freitas, Teixeira Simone Pádua
Universidade de São Paulo (USP), Faculdade de Filosofia Ciências e Letras de Ribeirão Preto, Pós-Graduação em Biologia Comparada, Av. Bandeirantes 3.900, Ribeirão Preto 14040-901, SP, Brazil.
Am J Bot. 2014 Apr;101(4):572-86. doi: 10.3732/ajb.1300355. Epub 2014 Apr 3.
Apocarpy (i.e., free carpels) is considered to be the basal condition for ovary development in angiosperms. Yet it only occurs in 10% of angiosperm species, of which another 10% are monocarpellate. Most legume flowers are monocarpellate. Species with polycarpellate gynoecia occur in about 15 genera with most representatives in Mimosoideae. In the present study, we analyze legumes with polycarpellate flowers with the aim of improving our understanding of gynoecium evolution.
Flowers of nine legume species from five genera were analyzed using a scanning electron microscope (SEM).
In Leguminosae, carpels usually form as individual primordia or protuberances. Inga congesta differs slightly from this pattern in that the central apex bulges outward before the formation of individual carpel primordia. While legumes usually develop entirely plicate carpels, flowers of Acacia celastrifolia and Inga bella show an intermediate type of carpel morphology with a distal plicate zone and a small proximal ascidiate zone. Carpels in Inga congesta and Archidendron glabrum are sometimes slightly fused at the ovary base. The orientation of carpel clefts seems to reflect the floral symmetry. They are directed to the floral center in mimosoids and caesalpinioids, whereas in Swartzia dipetala carpel clefts are oriented to the adaxial side.
Polycarpelly arose at least seven times independently in Leguminosae. The polycarpellate condition appears to be correlated with polyandry, and in most instances, it is accompanied by a profound change in floral organization from a closed to an open system.
心皮离生（即离生心皮）被认为是被子植物子房发育的基本状态。然而，它仅出现在10%的被子植物物种中，其中另外10%是单心皮的。大多数豆科植物的花是单心皮的。具有多心皮雌蕊群的物种大约出现在15个属中，大多数代表物种在含羞草亚科。在本研究中，我们分析了具有多心皮花的豆科植物，目的是增进我们对雌蕊群进化的理解。
使用扫描电子显微镜（SEM）分析了来自五个属的九种豆科植物的花。
在豆科中，心皮通常作为单个原基或突起形成。密集印加豆与这种模式略有不同，在于在单个心皮原基形成之前，中央顶端向外凸出。虽然豆科植物通常发育出完全具褶的心皮，但南洋楹和美丽印加豆的花表现出一种中间类型的心皮形态，具有远端具褶区和小的近端囊状区。密集印加豆和秃轴耳豆的心皮在子房基部有时会稍有融合。心皮裂缝的方向似乎反映了花的对称性。它们在含羞草亚科和云实亚科中指向花的中心，而在二瓣黑黄檀中，心皮裂缝指向近轴面。
多心皮现象在豆科中至少独立出现了七次。多心皮状态似乎与多雄蕊现象相关，并且在大多数情况下，它伴随着花的结构从封闭系统到开放系统的深刻变化。
