The seeds micromorphology and morphometry of certain Dactylorhiza (Orchidaceae) species distributed in Turkey

In this study, we examined the seeds of 7 Dactylorhiza taxa (D. nieschalkiorum and D. osmanica var. osmanica) of which 2 are endemic to Turkey (D. euxina var. euxina, D. iberica, D. romana subsp. romana, D. saccifera, D. urvilleana) in terms of morphological, micromorphological and morphometric properties. We analyzed the seeds using standard procedures of light microscopy and electron microscopy (SEM). The seeds collected from different localities were examined in terms of 22 characters, such as seed shape and size, length/width ratio, embryo volume, seed/embryo volume, percent air space, position of the embryo and seed surface features were analyzed. Furthermore, the morphometric measurements showed that some diagnostic characters could be important for these taxa. As a result of the study, the dendograms were formed based on the numerical analysis and important differences were determined in terms of examined characters among taxa. The characters of the seeds of genus Dactylorhiza are characteristic even in species level. The seed properties identified would help researchers on genus-related problems.