The Study of Reproductive Organs Development in Scrophularia striata Boiss

Flower development is a mystery which provides a useful means for understanding cell differentiation and genetic mechanisms needed for organogenesis. In this study، the development of reproductive organs of Scrophularia striata was investigated. The flowers were collected at different developmental stages، fixed in FAA، embedding in the paraffin wax and sliced using microtome after dehydration and then stained. Developmental stages of generative organs were studied and photographed using a light monitoring microscope. The results indicated that after evolution of vegetative meristem to reproductive meristem، bract and sepals primordium quickly formed. Primordium formation and evolution of petals and staminal were simultaneous. Evolution of sporogensis meristematic mass is done at the final stage. Ovaries، eggs، style and stigma had a rapid developmental stage. The anthers wall development was of tetrasporangiate type. The microspore''s tetrads had tetrahedral ornamentations and mature pollen grains were of ellipse shape and tricolpate. Nurse’s cells have a long stability layer and are often mononuclear. The megaspore''s tetrads had liner ornamentations. The ovules were of anatropous and placentation axis. Investigation showed that each flower has five sepals، five gamopetalus، four stamens، and dilocular gamocarpous pistil. The embryo sac development is of polygonum type.