Fig. 3.

Multivariate analysis (PLS by means of partial least squares projections) of glucosinolates (GSLs) in the leaves. GSLs were measured in plants from three wild cabbage populations KIM (blue symbols), OH (green symbols) and WIN (yellow–red symbols) originating in Dorset, England that were grown in a common garden and of which leaves were sampled in September 2006 (light coloured symbols) and in May and August of the following year (darker coloured symbols). The score plot a visualises the structure of the samples according to the first two latent variables. R²X[1] and R²X[2] depict the variance fraction explained by the latent variables. The ellipse in the score plots defines the Hotelling’s T2 confidence region and provides a 95% confidence interval for the observations. The loading plot b defines the orientation of the PC planes with the original variables. The full names of the GSL compounds are given in Fig. 1 and the “Glucosinolate analysis” section. tot aliphat totals of aliphatic GSLs, tot indole total of indole GSLs, total grand totals of GSLs, % aliphat percentage aliphatic of total. Model statistics for foliar GSLs with three significant components: R²X = 0.74, Q² = 0.49. (Color figure online)