M4 medium was used for prothallus root induction and sporophyte
(plantlet) formation. Prothallus cultures in M4 medium were
maintained in a 25 C incubator with a photoperiod of 12 h of
white light (15 wm2
). Chlorophyll was produced in the outermost
cells of the prothallus after 3 months. These outermost cells appeared
to be slightly green and tiny green gemmae differentiated
from the top of the prothallus branch. Four months later, a green
sporophyte (plantlet) with roots had developed as shown in Fig.
2C. Prothallus also differentiated into sporophytes when prothallus
cultures were placed in darkness. These sporophytes, however, did
not produce chlorophyll.