noun, plural: haustoria
In certain parasitic angiosperms, haustorium refers to the knob-like root structure that is used to penetrate into the host plant. It serves as a feeding organ for absorbing nutrients and water from the host plant. It may be regarded as an adventitious root or a type of an aerial root that grows into the tissues of a host plant. They are also referred to as sucking roots. It penetrates the cell wall of the host plant and then draw nourishment from the space in between the cell wall and plasma membrane.1 This is exemplified by the haustorial roots of mistletoe.
Word origin: Latin haustor (“drain, drink or suck”) + -ium
- sucking root
- parasitic root
- haustorial (adjective)
1Szabo, L. (July 3, 2001). "Hidden robbers: The role of fungal haustoria in parasitism of plants". PNAS. 98 (14): 7654–7655.