. Explant sterilization and in vitro propagation
The in vitro initiated cultures of Ph. squarrosus provided by
E. Wellmann were first placed on M1 medium. When the resulting
prothalli or calli were large enough to handle, they were transferred
to M2 medium and then transferred from time-to-time as
their increase in size warranted change to larger tubes and fresh
medium or transferred into liquid medium for suspension culture
initiation.