Seed Morphology in Species from the Silene mollissima Aggregate (Caryophyllaceae) by Comparison with Geometric Models

Abstract

The description of seed shape by comparison with geometric models allows shape quantification, providing the means for an accurate comparison between different species or populations. Geometric models described for the lateral and dorsal views of the seeds of Silene species are applied to the quantification of the shape in the seeds belonging to twenty populations of the eleven taxa of S. mollissima aggregate. Cardioid models LM1, LM5 and LM6 adjust differentially to the lateral views of the seeds, while models DM1, DM5 and DM6 are applied to the dorsal views of the seeds. Quantification of the lateral view of seeds with LM5 results in two groups of species of different geographic origin. The seeds more resembling DM5 include S. andryalifolia, S. badaroi, S. gazulensis, S. hifacensis and S. tomentosa, i.e., the taxa with a continental distribution from southern Spain to northern Italy; in contrast, the group of seeds with lower similarity to DM5 includes those from species in northern Africa and the Mediterranean Tyrrhenian islands: S. auricolifolia, S. hicesiae, S. ichnusae, S. mollissima, S. oenotriae and S. velutina. The description of the seed shape based on geometric models contributes to investigating the relationships between related species and constitutes a promising technique for taxonomy.

Comparison of Seed Images with Geometric Models, an Approach to the Morphology of Silene (Caryophyllaceae)

“…As a new morphological approach, we have described the lateral and dorsal views of Silene seeds comparing the seed contour with algebraically defined geometric figures, such as the cardioid, modified cardioid, or diverse ellipses. We provided a J index, a numerical value indicating the percentage of similarity between a defined seed silhouette and a given geometric figure, taken as a model [14][15][16][17][18]. The comparison of lateral seed…”

The Outline of Seed Silhouettes: A Morphological Approach to Silene (Caryophyllaceae)

“…[ 1 , 2 ]. An important proportion of the Silene species belong to the Northern Hemisphere, with regions of high diversity in the Mediterranean area [ 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 ], Iran and western Asia [ 11 , 12 , 13 ]. Other species have been described from India and the Himalayas [ 14 ], and even from China [ 15 ].…”

“…The shape of lateral seed views, with the hilum oriented towards one side, has often been termed as reniform, and it could be more precisely defined as “cardioid related”, based on the quantification by comparison with models derived from the cardioid curve. A variable degree of opening of the central side, corresponding to the proximity of the hilum, revealed different shapes that can be compared with algebraically defined geometric models derived from the cardioid [ 7 , 29 , 30 , 31 , 32 ]. In their dorsal views, the seeds may be convex or show concavities.…”

“…The proposed description of the lateral and dorsal views of Silene seeds was based on the consideration of the seed silhouettes as geometric figures. In relation to general seed shape, it allowed for comparing the seed outline with algebraically defined geometric figures providing a quantity, J index, that indicates the percentage of similarity of the seed silhouette with a given geometric figure taken as a model [ 7 , 29 , 30 , 31 , 32 ]. Related to seed coat ornamentation, and working specifically with seed silhouettes, we have analyzed recently 100 populations belonging to 49 species of Silene , one of Atocion and two of Viscaria [ 31 ].…”

10th Anniversary of Plants—Recent Advances and Further Perspectives

“…The biology and ecology of plant secondary metabolites, their identification, and biological and therapeutic activity from different aspects of the phytochemistry of edible, aromatic, medicinal, or potentially medicinal plants are represented in a significant number of articles [3,8,[35][36][37][38][39][40][41][42][43][44][45][46][47][48][49], as well as review papers [9,50,51]. The morphology and systematics of plants, as well as taxonomic methods, are also the subject of significant articles [52][53][54][55][56] and one review paper [57]. A similar number of papers are devoted to the scientific and practical aspects of ecology and the environment, comprising several articles [4,[58][59][60][61] and one review [62].…”