Primary roots of Dracontium eminate
from the flattened apex of the tuber and grow downward in all directions,
completely surrounding the tuber (
Fig. 9-12 ). Secondary roots start below the tuber apex and are subdivided
into many smaller roots. The strong and often contractile root system functions
not only in water- and nutrient-absorbtion, but also serves to support the
plant. The roots hold the tuber in a position that facilitates the formation
of the hollow spaces above and below the tuber. The tuber naturally assumes
a deeper position when the roots dry out after each growing season.