Further Studies on the Effect of Colchicine upon the Mitosis of the Stamen Hair in Tradescantia
1949 年 15 巻 1-2 号 p. 88-95
詳細
1949 年 15 巻 1-2 号 p. 88-95
1. When the stamen hair of Tradescantia is cultivated in an agar plate containing colchicine the whole process of c-mitosis can be observed. By observation of material in the living state, the time required for c-mitosis was measured. The minimum time required, when 0.05% colchicine was used, was 430 minutes (about 2.8 times as much time as required for normal mitosis), and with the 0.1% treatment, 343 minutes (about 2.2 times as much as normal mitosis).
2. The increased duration required for c-mitosis as compared with normal mitosis is due to the greatly increased duration of the intactness or staying period of the chromosomes (about 8-10 times as much as that of normal mitosis). The increase of time necessary for the formation of chromosomes and uncoiling namely the time required for the prophase and telophase was not considerable.
3. The time required for c-mitosis varies according to the concentration of colchicine. In explanation the author's hypothesis of the submicroscopic structure of the achromatic figure was introduced and the mechanism of colchicine functions discussed.
