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Abstract
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Flower development is a mystery which provides a useful means for understanding cell differentiation and genetic mechanisms needed for organogenesis. The aim of this research was reproductive organ development in Verbascum pseudodigitalis, as a medicinal plant, that is necessary for understanding its reproduction and survival. In this study, microsporogenesis, megasporogenesis and gametophyte development of V. pseudodigitalis belonging to Scrophulariaceae were investigated. The flower was collected at different developmental stages, fixed in FAA, embedded in paraffin wax and sliced using a microtome after dehydration and then stained. The developmental stage of generative organs was studied and photographed using an alight microscope. The results showed that stamens are five, filaments usually woolly, young anthers wall development followed the dicotyledonous type and anther is tetrasporangiate witch composed of an epidermal, an endothecium, a middle layer and then tapetum layer. In this species the endothecium is fibrillar, and the tapetum cells possess in all developmental stages characteristics of the secretory type. Tapetum layer cells have a long stability and are binucleate. Pollen grains were radially symmetrical, tricolpate and the microspore tetrads have a tetrahedral and tetragonal arrangement .The ovary is superior, bicarpelly, syncarpous whit a large number of ovules arising on a swollen axile placenta. The ovule is anatropous unitegmic and crassinucellate. Development of the embryo sac conforms to the Polygonum type
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