GROWTH, DEVELOPMENT AND GEMMA FORMATION IN THE LIVERWORT SCAPANIA NEMOROSA AS INFLUENCED BY L‐ARGININE, L‐HISTIDINE AND L‐GLUTAMIC ACID

New procedures of aseptic bryophyte culture which permitted the alteration of the culture medium during the life cycle were used to investigate development and gemma differentiation in Scapania nemorosa from the aspect of organic nutrition. Cultures started from gemmae (asexual reproductive structures) were treated with l ‐arginine, l ‐histidine and l ‐glutamic acid upon reaching each of 3 developmental stages: Cell Mass stage, Juvenile stage, and Early Adult stage. Ten weeks after each treatment, quantitative determinations of growth and gemma formation, as well as a qualitative appraisal of the effect of treatment on development, were made on representative cultures. In addition, an amino acid analysis was made of young plants which had not produced gemmae, of older plants which had produced gemmae, and of gemmae. The results of the culture experiments indicate that all 3 amino acids are stimulatory to production of gemmae and that the degree to which this is so is contingent on the ontogenetic stage treated. Moreover, the qualitative data, in conjunction with the amino acid analysis, indicate that each compound influences gemma formation in a somewhat different manner.