The functional
megaspore undergoes three successive mitoses resulting in the formation of an 8- nucleate embryo sac of the Polygonum type.
Megaspores were considered to have germinated when an apical globular green structure with a crown of rhizoids was observed (Wunder et al., 2009).
This single haploid
megaspore undergoes three consecutive mitotic divisions to produce two, then four, and finally eight haploid nuclei within a single cell in the ovule.
megaspore A haploid spore (N) that will develop into a female gametophyte.
Twenty-five
megaspores were placed in each glass vial (4.5 x 10 cm) with 25 mL of the culture medium, with four repetitions for each treatment.
Sporangium wall pigmented with brown;
megaspores with short ridges, wart-like projections (tuberculate to papillate) or almost smooth; plant terrestrial or amphibious in wet clay soils or on rock outcrops.
However, not all seed-fertile triploid Musa accessions generate a high frequency of 2n
megaspores (Ortiz, 1995).
The inner integument initiates first, and then the outer integument develops into a small protuberance at the
megaspore mother cell stage.
Twenty five
megaspores were placed in each glass vial (4.5 x 10 cm) with 25 mL of the solution and there were six repetitions for each treatment.
megasporocyte:
Megaspore mother cell; this diploid cell undergoes meiosis to produce four haploid
megaspores in the ovules of angiosperms.
and ultrastructure of
megaspores and microspores of Isoetes savatieri
However, in most ovules, shortly after megasporogenesis from one to seven nucellar cells in the area adjacent to the functional
megaspore enlarged and their nuclei became prominent.