Figure 5.

Morphometric analysis of ivy and grapevine leaves. (a) An example of leaf outlines analysed from a shoot of common ivy (H. helix). Shoot tip and base are indicated. (b) Principal components (PCs) representing asymmetric shape variance using elliptical Fourier descriptors (EFDs). Negative PC standard deviation values are of opposite asymmetric orientation compared to positive values. Per cent asymmetric shape variance explained by each PC is provided. (c) An example of leaf outlines analysed from a grapevine shoot (specifically, Vitis xdoaniana, for which each of the nine leaf pairs have an opposite orientation, see table 3). The analysable leaf pairs for a shoot equals n − 1, where n = total leaf number. In this study, 20 different Vitis and Ampelopsis (a closely related genus to Vitis) species and hybrids were analysed. (d) PCs representing shape variance in 17 Procrustes-adjusted homologous landmarks. Note that almost all asymmetric shape variance is restricted to PC4, explaining 10.5% of total shape variance, which is analysed in table 3.