Fig. 2.

Inflorescence architectures and schematic representations of LFY and UFO expression patterns in different inflorescence types. (A) Schematics of common inflorescence morphologies observed in angiosperms. (B) The raceme of Arabidopsis thaliana. The apical meristem is an indeterminate inflorescence meristem (IM) with determinate floral meristems (FM) arising in the axils of the bracts (br). (C) The cyme of Petunia hybrida. The sympodial meristem (SIM1) is converted into an FM, and the uppermost lateral meristem takes over as a sympodial meristem (SIM2). The SIM2 is in turn converted to an FM with its uppermost lateral meristem taking over as the next SIM. s, sepal. (D) The panicle of Oryza sativa. The IM is indeterminate, forming primary branch meristems (PBMs) on its flanks, which themselves form secondary branch meristems (SBM; shown in the right-hand inset). (E) The capitulum of Gerbera hybrida. The IM forms multiple FMs on a flattened head-like structure. Outer FMs may form bilaterally symmetrical ray florets (RF) or smaller ray florets (i.e. trans florets, TF), and inner FMs form radially symmetrical disc florets (DF). The whole structure is subtended by a ring of bracts, known as involucral bracts (ibr). Blue regions correspond to LFY expression, yellow regions correspond to UFO expression, green regions correspond to LFY+UFO expression and grey regions correspond to TFL expression. All images taken by the authors.