Research into biological effects of 12C6+ ions with 46.6 MeV/u on four kinds of plant seeds

The biological effects of 46.6 MeV/u 12C6+ ions on four kinds of plant seeds were studied at HIRFL of Institute of Modern Physics, Academia Sinica. The results indicate that serious injuries were presented not only on external features of the seeds but also internal cells due to the bombardment and penetration of the ions. The heavy ions can significantly inhibit germination and growth of the seeds and can affect physiological functions. In root tip cells of irradiated seeds, a great variety of chromosomal aberrations were observed and the aberration frequencies were greatly higher than that of the corresponding controls. Serious damages of some organelles were induced by the ions. Damaged DNA can be repaired to some extent. Median lethal doses and inactivation cross-sections of the four kinds of plant seeds are determined and the differences of radiation sensitivity between different seeds are found. The correlations of organelle damages with abnormal physiological processes and the repairing process of damaged DNA are discussed