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A green‐pigmented callus of the moss, Sphagnum imbricatum Hornsch. ex. Russ., was induced and a chlorophyllous cell suspension culture was established using a modified Murashige and Skoog's medium without plant hormones. Cell growth in the light in the presence of glucose started after a short lag and was exponential for 12 days. The chlorophyll level was about 15 μg (mg cell dry weight)−1 and photosynthetic activity ca 20 to 50 μmol O2 (mg chlorophyll)−1h−1. Cell growth in the light was negligible in the absence of glucose under ordinary air, but photoautotrophic growth was possible under elevated CO2 concentrations. In the dark, the moss cells grew heterotrophically and continued to synthesize chlorophyll, although at a much reduced rate. The suspension‐cultured cells redifferentiated protonemata and shoots when transferred to solid Knop's medium. In contrast to the callus cells, which could not assimilate nitrate, redifferentiated plantlets could use nitrate as the sole nitrogen source.

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ABSTRACT:The electrolytic polymerization of tetrahydrofuran (THF) was carried out in bulk by using tetrabutylammonium perchlorate as an electrolyte. Poly-THF was obtained from the anolyte. The yield of the polymer increased with the reaction time and leveled off at about 70%. The molecular weight of the polymer increased proportionally to the yield of the polymer as was observed in the living polymer system. About two moles of hydroxyl end group were determined per mole of the polymer. In the polarographic measurement, THF gives no oxidation wave. From the results obtained an initiation mechanism is proposed, involving the perchlorate radical and proton. The presence of radical species is indicated by the electrolytic copolymerization of methyl methacrylate and acrylonitrile.KEY WORDS Electrolytic Polymerization/Tetrahydrofuran/Initiation/ Perchlorate Radical(Polytetrahydrofuran/ Although many reports on the electrolytic polymerization of vinyl monomers have been published, there have been few studies concerning ring-opening polymerization of cyclic monomers by the electrochemical process 1 • In respect of cyclic monomers, the electrolytic polymerization of tetrahydrofuran (THF) has been studied in our laborator/ and by Heins, 3 but the mechanism of the polymerization has not yet been clarified. We wish to report, in this paper, some results of the electrolytic polymerization of THF and discuss the mechanism of the reaction in detail.