Promotion of Pylaisiella selwynii growth and gametophore formation by octopine and cytokinin

Growth, branching and gametophore formation by protonema developing from spores of the moss Pylaisiella selwynii were promoted by octopine, an unusual amino acid found in crown gall tumors. Cytokinin (0.01 μ M ) in combination with octopine (0.1 μ M to 1 m M ) increased the number of gametophores formed and decreased the time required for their development. The combined effect of these two compounds was similar to that obtained with virulent agrobacteria. At higher cytokinin concentrations, protonemal buds formed abnormal masses of cells rather than normal gametophores. Common amino acids and auxins, alone or in combination with cytokinin, had relatively little effect on the development of the moss.