Figure 2.

Development stages of the S. marianum achene defined according to their morphological characteristic. (a) Six achene developmental stages were defined. For the developmental stages 4, 5 and 6 achenes were manually dissected to allow the visualization of both seed and pericarp. The capitula morphology corresponding to each defined achene developmental stage is presented. Note that the capitula morphology is not predictive of the fruit developmental stage (see text for explanations). (b) Morphological features of achene maturation during time such as achene, seed, and pericarp length, dry weight (DW) and day of flowering (DAF). Each value represents means ± SD of n = 10 independent sampling. Different letters indicate significant differences at p < 0.05.