Development of Male and Female Reproduction Organs in ‎Moldavian Dragonhead, Dracocephalum moldavica L. (Lamiaceae)‎

Due to its great medicinal value, the Moldavian dragonhead, belonging to Lamiaceae, is naturally distributed in Europe, Siberia, and Central Asia and planted in different Iranian provinces. This research studied the development of male/female reproductive organs. Flowers and buds in different stages of development were fixed and preserved in order to prepare microtome sections using appropriate solutions and embed them in paraffin. Hematoxylin-eosin was used to stain the slices. Based on the results, despite the relative simultaneity of the formation of stamen primordium and carpel, stamens develop faster than ovules. Nurses’ cells in secretory and plasmodium types are rectangular, spindle-shaped, and often mononuclear or more. The microspore’s tetrads had tetrahedral ornamentations, and mature pollen grains were hexacolpate with reticulate ornamentation of the exine. The ovules were anatropous, unitegmic, and tenuinucellate. The functional megaspore has a micropillar position, and the embryo sac development belongs to the Polygonum type.