Micromorphological studies on nutlets of some onosma l. (boraginaceae) species from Turkey

Abstract

In this study, the nutlet micromorphology of 9 taxa of Turkish Onosma species viz., O. sericeum Willd., O. cassium Boiss., O. rutilum Hub.-Mor., O. sieheanum Hayek, O. albo-roseum Fisch. & Mey. ssp. albo-roseum var. albo-roseum, O. inexspectatum Teppner, O. auriculatum Aucher ex DC., O. heterophylum Griseb and O. thracicum Velen. was examined using both light and scanning electron microscopy. According to surface ornemantations, three main types, reticulate, rugose and elongated, and 2 subtypes (rugose and rugose-reticulate) were defined and illustrated. Nutlet morphology of the examined specimens exhibits some variation in size and shape. Nutlet size ranges between 2-7 x 1.5-5 mm. Nutlets are ovoid, broadly ovoid oblong-ovoid and bipyrimidate.