ABSTRACT
Considerable work has been done on chemical regulation of sexual reproduction in bryophytes grown in vitro. Although the conditions of growth in axenic cultures are in some ways far from natural, it is hoped that ultimately the data obtained in artificial conditions will be helpful in understanding the way sexual reproduction is regulated in vivo. Among the chief chemical factors whose effect has been investigated on the induction of gametangia are growth regulators, sugars, chelating agents, and nitrogenous substances. The parameters taken into consideration are the time of gametangial formation, percentage of fertile gametophytes, and number of antheridia and archegonia produced per thallus/ gametophore. High auxin levels inhibit growth in the majority of the investigated liverworts and mosses. In some bryophytes auxins prove inhibitory at all levels, whereas in others they stimulate the growth at low concentrations.
