Tuberous root

A tuberous root is a modified lateral root, enlarged to function as a storage organ. It is thus different in origin but similar in function and coarse appearance to a tuber. Examples of plants with notable tuberous roots include the sweet potato (the most popular tuberous root), cassava and Dahlia.It is a structure used to perenniallize the plant so in can survive from one year to the next.

The thickened roots are storage organs that differ from true tubers. The massive enlargement of secondary roots typically represented by sweet potato ("Ipomoea batatas"), have the internal and external cell structures of typical roots. True tubers have the cell structure of stems, while in root tubers there are no node and internodes or reduced leaves. One end called the proximal end has crown tissue that produces buds that grow in stems and foliage. The other end called the distal end normal produces unmodified roots. In true tubers the order is reversed with the distal end producing stems. Tuberous roots are biennial in duration, the first year the parent plants produces the stem tubers and in the fall the plant dies, the next year the stem tubers produce a new plant and are consumed in the production of new roots and stems and flowering, the remaining tissue dies while the plants generates new stem tubers for the next year.

Plants with root tubers are propagated in late summer to late winter by digging up the tubers and separating them, making sure that each piece has some crown tissue and replanting.

ee also

* Taproot
* Stem tuber