Morphological and histological studies of ovary development

Morpho-histological changes are followed before and after pollination. The two twin carpels of white color and same size are carried by the same petal. The third large carpel is carried by the third petal. After pollination, the color of the carpels initially white turns to green. The dissection of the carpels, makes it possible to see that the three ovules are coloured in pink, but one is more coloured than the two others. Only the carpel containing a strongly colored ovule develops into a fruit. The other two degenerate by a deposit of polyphenols. A histological study followed the regression of the twin carpels and the formation of the embryonic sac of the third carpel. This work shows the change in color of the ovule from its natural translucent state to a pink coloration, corresponding to the increase in mitotic intensity of the nucellus cells. The change from pink to white of the fertilized ovum that, after forming the embryo sac, transforms into a seed.