Cracking the omega code: hydraulic architecture of the cycad leaf axis.

ABSTRACT: Background and Aims:The leaf axis of members of the order Cycadales ('cycads') has long been recognized by its configuration of independent vascular bundles that, in transverse section, resemble the Greek letter omega (hence the 'omega pattern'). This provides a useful diagnostic character for the order, especially when applied to paleobotany. The function of this pattern has never been elucidated. Here we provide a three-dimensional analysis and explain the pattern in terms of the hydraulic architecture of the pinnately compound cycad leaf. Methods:The genus Cycas was used as a simple model, because each leaflet is supplied by a single vascular bundle. Sequential sectioning was conducted throughout the leaf axis and photographed with a digital camera. Photographs were registered and conve

SUBMITTER: Tomlinson PB 

PROVIDER: S-EPMC5838846 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature