The Origin, Development and Germination of Bulbils in Two Dioscorea Species

Abstract
The origin, development and germination of aerial bulbils of Dioscorea alata and D. bulbifera are described and the significance of the primary nodal complex (PNC) in bulbil ontogeny discussed. Further evidence is provided for the view that the PNC, or its initial, is the site of renewed growth in Dioscorea species.