Abstract
As the result of a low-temperature treatment (0°C) of Trillium kamtschaticum through full cycle of meiosis, the following facts were obtained.
Interstitial chiasma frequency was seen to increase remarkably at metaphase I, and the rate of increase was in proportion to the arm length among individual chromosome arms.
As for the chromosomal aberrations observed at metaphase I, there was a frequent appearance of univalents, fragments and chiasma breakages. The bridges appeared at anaphase I were apparently caused by chiasma breakages.
The increase of interstitial chiasmata, and the relationships between the frequency of chiasma breakages and that of the appearance of bridges are explained on the basis of Matsuura's Neo-two-plane theory.
