Mitotic Abnormalities in the Root Meristem and Ovular Tissue of Clivia miniata Regel. and the Seasonal Variation of their Occurrences

Sticky chromosome bridges and chromosome breaks in the ana- and telophase have been found in the root tips and the ovular tissue of Clivia miniata growing in the greenhouse and outdoor.2. The occurrence of these irregularities was frequent in the root meristem fixed in summer, but infrequent in the material fixed in winter.It is most probable that there is a seasonal variation of frequency in the occurrence of aberrant cells.3. The patterns of abnormalities in the ovular tissue are different from those in the root meristem.4. It is suggested from the present data obtained that both the external conditions enclosing the plant, especially temperature, and cellular metabolic conditions caused by the heritable internal factor are responsible for the aberrations.5. Various degrees of pollen sterility have been observed. Mitotic divisions in the shoot meristem were quite normal.