Galactose inhibition of auxin‐induced cell elongation in oat coleoptile segments

Abstract

Auxin‐induced cell elongation in oat coleoptile segments was inhibited by galactose; removal of galactose restored growth. Galactose did not appear to affect the following factors which modify cell elongation: auxin uptake, auxin metabolism, osmotic concentration of cell sap, uptake of tritium‐labeled water, auxin‐induced wall loosening as measured by a decrease in the minimum stress‐relaxation time and auxininduced glucan degradation. Galactose markedly prevented incorporation of [14C]‐glucose into cellulosic and non‐cellulosic fractions of the cell wall. It was concluded that galactose inhibited auxin‐induced long‐term elongation of oat coleoptile segments by interfering with cell wall synthesis.