Silene seeds from the colection of Ana Juan (University of Alicante, Spain)

.Composed images containing 20 seeds of each species for the comparison with geometric models (Model 1 to Model 8).

The images containing twenty seeds were used for calculation of J index. J index is

defined by:

J index= (area S)/ (area T) ×100.

Where S is the area shared between the seed and the model and T, the total area occupied by both figures. J index ranges between 0 and 100, reaching maximum values when the geometric model and the seed image areas coincide. A high value of J index, i.e. high similarity with a given model, means a precise definition of seed shape for a particular species. A good adjust to the model is considered when J index values were superior to 90.

Area calculation was done by superimposing the model on each seed image in groups of 20 seeds, searching a maximum adjustment between the shapes of the seeds and the geometric model. Two files are provided for each composition: 1) A file (JPG format) with the geometric models in black, that is useful to obtain total area (T) with the software ImageJ; and 2) Another file in JPG format with the geometric models in white, useful to obtain the values of area shared between the geometric figure and the seed image (S) in ImageJ. Image composition with seeds and models was done in Corel PHOTO-PAINT X7, and area quantification in ImageJ. Figure 1 illustrates examples of the adjustment between seed images and the geometric models with indication of the areas measured for the calculation of the J index.