The tuber begins its growth with the swelling of the seedling hypocotyl. Later, the cavities are formed when cork-generating meristems arise in the inner parenchymatous tissue forming a cork-like wall, cutting off carious shaped and sized enclosures.
The tuber's growth begins with the swelling of the hypocotyl, followed by the formation of cavities as cork-producing meristems develop in the parenchymatous tissue to create a cork-like wall that isolates irregular spaces.