STUDIES ON THE CYTOGENETIC AND GENETIC EFFECTS OF FLUORIDE ON BARLEY.: I. A COMPARATIVE STUDY OF THE EFFECTS OF SODIUM FLUORIDE AND HYDROFLUORIC ACID ON SEEDLING ROOT TIPS

Abstract

The effects of sodium fluoride and hydrofluoric acid on barley were determined and compared following treatments of seedling root tips at three different concentrations (1 × 10−2M, 1 × 10−4M, 1 × 10−6M) and for six different durations (12, 24, 36, 48, 60, and 72 hr). Treatment with a 1 × 10−2M concentration of either sodium fluoride or hydrofluoric acid markedly slowed the rate of seedling growth. However, no inhibition of growth was observed following treatment with a 1 × −4M or a 1 × 10−6M concentration of either agent. Chromosomal aberrations were induced and mitosis was inhibited by each of the three different concentrations of both sodium fluoride and hydrofluoric acid. The sodium fluoride treatments induced a higher frequency of chromosomal aberrations than did the hydrofluoric acid treatments, possibly due to differences in pH and in the total available fluoride ions. These treatments produced bridges, fragments, chromosome gaps, binucleate cells and micronuclei.