Seed micromorphology of Orchis Tourn. ex L. (Orchidaceae) and allied genera growing in Edirne province, Turkey

Abstract. In this study, the seed micromorphologies of eight taxa of Anacamptis, Neotinea and Orchis growing around Edirne province (Turkey) were investigated using light microscopy and scanning electron microscopy (SEM). Slides prepared with glycerin jelly were used for measurements under the light microscope and fine details of seed testae characteristics were observed with SEM. Seeds of the investigated orchid taxa are fusiform shaped and of different shades of brown. Their lengths and widths are different among the taxa and range between 0.263–0.640 mm and 0.118–0.208 mm, respectively. Testa surfaces of Orchis mascula subsp. mascula, Orchis purpurea subsp. purpurea and Orchis simia subsp. simia, are smooth while those of Anacamptis coriophora, Anacamptis laxiflora subsp. laxiflora, Anacamptis morio subsp. morio, Anacamptis papilionacea and Neotinea tridentata subsp. tridentata are reticulate. An identification key based on seed morphologies and sizes is suggested for the first time, including testae structures of orchids growing in Edirne province. The overall results of the study showed that morphological structures of orchid’s seeds could be used as diagnostic characters in identification.