Reversible Inhibition of Cell Division and Enlargement in Plant Tissues by 2, 6-Diaminopurine.

Abstract

2,6-Diaminopurine (DAP) inhibits cell division in tobacco stem callus and habituated callus cultures and prevents bud formation in the stem cultures. It reduces cell enlargement in tobacco pith cultures and in etiolated pea stem or Avena coleoptile segments. Adenine, arginine, guanine, hypo-xanthine, and xanthine were tested in attempts to reverse the inhibition by DAP of callus growth and bud formation in tobacco stem segments. Adenine was very effective and slight reversal was obtained with guanine and hypoxanthine. Reversal of the DAP inhibition of tobacco pith cell enlargement was obtained with adenine and guanine, but adenlne was more effective. No other compounds were tested on this tissue. Reversal of the DAP inhibition of etiolated pea stem segment elongation was attempted only with adenine, adenosine, and adenylic acid. All 3 compounds gave partial reversal. The results indicate the participation of purines, particularly adenine, in both cell enlargement and division in plants.