Regeneration of protonema with multiple dna content from isolated protoplasts of the mossFunaria hygrometrica

Summary Protoplasts can only be produced from chloronema and the youngest cells of caulonema. After formation of cell walls on a plasmolytic medium protoplasts develop into protonemas on a regular Knop-medium. 6–11 % of the regenerating protonemas however are smaller than the control and show an equally irregular growth, one protonema out of 200 remains exceptionally small. Cytofluorometry with fluorochrome Hoechst 33258 proves the smaller prctonemas to have a higher DNA content than the control with highest frequencies appearing at the 2 C and 4 C level. These protonemas therefore derive from diploid or tetraploid protonema cells.