Axial placentation is observed in:

Placentation is the arrangement of ovules within the ovary. Placenta is the tissue that nourish the ovules inside the ovary.

Axile placentation:

When the placenta is axial and the ovules are attached to it in a multilocular ovary, the placentaion is said to be axile, as in China rose, tomato and lemon. This is also seen in Solanaceae family (like Petunia, potato, etc.) and Liliaceae family (like onion)