Cell and Tissue Journal

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.

Abstract Aim: Study of gynoecium and female gametophye is important in botany and plant taxonomy. This research was done for studying the developmental stages of ovule in Ranunculus arvensis and comparing with other reported taxa in this family.
Material and methods: Flowers and young buds were collected in different developmental stages, fixed in FAA₇₀ and stored in 70% ethanol. Specimens were sliced using microtome after dehydration and embedding in the paraffin wax and stained. Developmental stages of ovule and embryo sac were studied and photographed using a light monitoring microscope.
Results: Results showed that the ovule is anatropous, unitegumic with 4 or 5 layers and full-nucellus. Embryo sac development is followed monospori and polygonum type. Increasing of antipodal cells and in some cases increasing of synergids were observed. Also their nuclei were polyploid. Archeosporial cells were surrounded by callosic wall after their formation.
Megaspore's tetrads had linear and T-shaped ornamentations. Embryo sac was large with irregular shape and considerably grows longitudinal in its maturation step.
Discussion: Results showed that although the overall pattern of ovule development in the studied species is similar to previous reports, but the tetrad arrangement, increasing of antipodal and synergid cells, and the presence of Hypostase, Postament and Nucellar Cap is the specific characteristic for this species.