Regeneration of bog liverworts



Leafy liverworts of many species regenerate in slabs cut at various depths from peat cores from two widely different sites. Two patterns are recognizable. Species such as Calypogeia fissa (L.) Raddi, Lophocolea spp., Lophozia ventricosa (Dicks.) Dum., Barbilophozia floerkii (Web. & Mohr) Loeske and Riccardia latifrons (Lindb.) Lindb., which lack underground axes, regenerate most abundantly at the surface but not below 9 cm depth. Other species such as Kurzia pauciflora (Dicks.) Grolle, K. sylvatica (Evans) Grolle, Odontoschisma sphagni (Dicks.) Dum., O. denudatum (Mart.) Dum., Cladopodiella fluitans (Nees) Buch, Cephalozia bicuspidata (L.) Dum. and C. connivens (Dicks.) Lindb. which have underground axes, may regenerate poorly at the surface, much better down to 12 cm or so, and arc still found at 24–30 cm depth. These patterns were found in cores from a live Sphagnum-covered surface and from a much older cut peat surface recently recolonized by liverworts. These results suggest that regeneration is mainly from underground axes rather than from spores or gemmae. The biomass of the underground axes seems to be large. All the axes have fungal associates, and it possible that they are partially saprophytic or parasitic.