The relationship between days to 50% of total germination and seed properties. (a) Seed volume, (b) GA concentration, (c) GA:ABA ratio, and (d) crude fat in the seed kernel. Each point indicates an introduced (blue) or native population (green). Seed sources, collection times and number of replicates were given in Supplementary Tables S1 and S2. The r and P values are from Pearson correlations. The solid line represents a significant linear correlation.