Curvature Analysis in Seed Surface of SEM Images of Silene Species from Türkiye

Abstract

Recently, based on light microscopy images, the tubercle structure on the seed surface of 100 Silene species was quantitatively described, including tubercle width, height, and curvature associated with general morphometric data. Curvature measures the rate of change of the tangent vector in a curve and can be calculated by the following methods described for Arabidopsis roots. Here, we apply curvature measurements to the SEM images of 40 Silene species from Türkiye, demonstrating that a quantitative analysis of tubercles can be made based on SEM images with similar results to optical photographs. The association of morphometric tubercle data allows for classification into six groups, five of them corresponding to described shapes: rugose (two groups), echinate, mammillate, and papillose, and a sixth group of tubercles plane on top. The curvature values vary between 20 and 200 mm−1 and differ among the morphological tubercle types described. The correlation of curvature values with other general measurements and morphological seed characteristics is investigated. Tubercle quantification not only is a useful tool for Silene taxonomy, but also provides the basis for the analysis of the genetic control and developmental effects on tubercle structure and shape in the seed surface.