Vivipary is the phenomenon of giving birth to young ones in advanced stage of development. It occurs in mangroove plants, where seeds cannot germinate on the ground because of the excessive salt content and lack of oxygen in marsly habitat.
(a) The embryo of the seed continues growth while the latter is attached to the parent plant.
(b) Hypocotyl elongates and pushes the radicle out of the seed and the fruit.
(c) The seeding becomes heavy. As a result, it breaks it connection with the fruit and falls down in the salt rich muddy water in such a position that the plumule remains outside the saltish water while the tip of the radicle gets fixed in the mud. This protects the plumule.
(d) The radicle quickly forms new roots and establishes
the seedling as a new plant.