Cell and Tissue Journal

Abstract Aim: 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. Material and Methods: 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. Results: 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. Conclusion: Investigation showed that each flower has five sepals, five gamopetalus, four stamens, and dilocular gamocarpous pistil. The embryo sac development is of polygonum type.

Abstract Aim: Since applied and molecular studies are increasing in Ranunculaceae, the study and understanding of the flower development in the familyis necessary. In this research ovule developmental stages in Adonis flammea were studied.
Material and Methods: The young flowers and buds were sampled in different developmental stages, fixed in FAA₇₀ and kept in 70% ethanol. Samples were embedded in paraffin after dehydration and sliced using microtome. Staining was carried out with PAS and Hematoxylin. Prepared slides of different developmental stages were studied using light microscope and are photographed.
Results: Results showed that ova in A. flammea are anatropous, bitegumic and crassinucellate. Micropylar channel was constructed with inner integument. Megasporocyte produces both linear and nonlinear arrangement of tetrads after meiosis. Embryo sac development follows to the Polygonum type. Antipodal cells are persistent that degenerate at the cellular endosperm stage. Cytoplasmic connections of embryonic sac cells, degeneration of some ova, consciously abortion of ovules and embryo were also observed.
Conclusion: The patterns of ovule and embryo sac development are accordance with the Angiosperms and Polygonum type. But antipodal cells persistence, nucellar cap formation, cytoplasmic connections between embryo sac cells, fertilization failure and embryotocia in some ova are characters of the studied species that can due to genetical or environmental factors.