Beitrag zur Wuchsform und Biologie der Gefäßpflanzen des hercynischen Raumes: 8. Armoracia rusticana G. Gaertn., B. Mey. & Scherb. (Meerrettich; Brassicaceae)

Abstract

Barniske, A.-M., Heklau, H., Jäger, E. J.: Growth form and biology of Hercynian vascular plants. 8.
Armoracia rusticana G. Gaertn., B. Mey. & Scherb. (horseradish, Brassicaceae). - Hercynia N. F. 49
(2016): 1 – 25.

Horseradish was studied with special emphasis on its enigmatic origin, affinity, variation, dispersal (by
detached roots only), ecology (soil, plant communities), worldwide distribution and climatic envelope;
morphology (seedling, structure and sequence of leaves, heterophylly indicating its origin on sites
flooded in spring: long petiolate rosette leaves with very large blade, small pinnatisect leaves at the base
of the flowering stem, further up lanceolate leaves, the uppermost sessile), brochidodromous nervature,
hydathodes, seasonal development of shoots, leaf rhythm, inflorescence, sterile fruits, flower galls, root
system, regenerative root sprouting after damage), life history (germination, clonality, flower initiation,
flower visitors, demand of cold, shoot innovation), anatomy (aequifacial, amphistomatic, subsucculent
structure of rosette leaves; anisocytic stomata apparates, structure of petiole as reason of its bending
strength, root system and structure). The dispersal is only by root cuttings (or by roots teared off), not by
root suckers in intact plants. The petiolate rosette leaves are developed on one ramet only in the year(s)
before flowering. The reason of sterility is not a consequence of hybridization or of self-incompatibility
alone, but of a whole complex of irregularities in the progamic and postzygotic phase.