In Amorphophallus and Colocasia $(Ariods)$ an extremely enlarged underground vertical stem meant for vegetative reproduction and storage is
Tuber
Corm
Bulb
Rhizome
Indian telegraph plant $(Desmodium\,\, gyrans)$ belongs to
A disc like reduced stem is found in
Coma that is useful for seed dispersal in Calotropis is
Nodulated roots occur in