Effects of auxin and cytokinin on induction of sister chromatid exchanges in cultured cells of wheat (Triticum aestivum L.)

Summary In order to know the mutagenic effects of synthetic auxins (NAA, 2,4-D, and 2,4,5-T) and a cytokinin (kinetin) in vitro, sister chromatid exchanges (SCEs) were analyzed in cultured cells of a hexaploid wheat (Triticum aestivum L.). In the MS medium supplemented with 2.0 mg/l 2,4-D, the mean number of SCEs per cell was 15.2, and per pg of DNA, 0.42. No significant effect was found in the treatments of NAA or 2,4-D at concentrations of 0.5–10.0 mg/l, whereas more than 2.0 mg/l of 2,4,5-T induced dramatic increases of SCEs. Kinetin itself had no significant effect on SCE induction, but there was a tendency that SCEs induced by 2,4,5-T were suppressed by kinetin.