Chromatid Aberrations Induced by π⁻ Mesons in Vicia Faba Root Meristem Cells

Summary

Chromatid aberrations were induced in Vicia faba root meristem cells by 31, 92, and 117 rads of π⁻ mesons at the peak of the depth–dose distribution. The irradiation was carried out under both aerobic and anoxic conditions. The yields of various types of aberrations were obtained in cells at 4-hour intervals up to 24 hours after irradiation. A rough estimate of the oxygen enhancement ratio indicated it was 1·8. In cells irradiated at the peak of the depth–dose distribution the aberrations were not distributed among cells according to random expectations. Too many cells had no aberrations and too many had multiple aberrations. This is a reflection of the way in which energy is dissipated when a π⁻ meson stops and produces stars in the medium.