تکوین اندام زایشی ماده در گلابی (Pyrus communis L.)

This study provides a detailed examination of the female reproductive organ development in pear (Pyrus communis L.). Samples were collected, fixed in FAA solution, embedded in paraffin, and sectioned using a microtome. Results revealed that pear inflorescence is a corymb, the gynoecium is syncarpous, and the style is solid.The ovules are anatropous, bitegmic, and crassinucellate, with the embryo sac of the Polygonum type. During early development, the archesporial cell differentiates into a megaspore mother cell, and the megaspore tetrad forms in a linear arrangement. Only the chalazal megaspore becomes functional and proceeds through megagametogenesis to form a mature embryo sac consisting of seven cells and eight nuclei. Additionally, the presence of a hypostase at the chalazal pole and a funicular obturator in the ovules was observed, both playing a crucial role in embryo sac nourishment and pollen tube growth. Embryogenesis in pear follows the Asterad type, characterized by an initial T-shaped division of the zygote, followed by the development of a dicotyledonous embryo. By understanding the developmental timing and structure of the ovule and embryo sac, our study provides useful insights for optimizing pollination timing and improving reproductive success, which can ultimately enhance fruit set and guide breeding programs.