Allorizic

Allorizic

In botany, the term allorrizic or allorizic refers to a root system or apparatus, typical of dicotyledons and gymnosperms, in which the main root remains vital for the entire duration of the plant, and can present itself with different structures.
a) – tap-shaped, where the main root grows continuously (secondary growth) penetrating the soil deeply reaching up to 10 times the size of the epigeal part of the plant.
b) – in collated form, where the second order roots grow to the size of the main root, arranging themselves in bundles (beech, apple, castor) and often the whole system develops more in width than in depth (poplar, potato).
The term allorrizic is opposed to that of omorrizic or homorizic.