Effects of D-galactose on the ultrastructure of bentgrass root apices

Abstract

To study the effects of growth-inhibitory concentrations of D-galactose on the morphology and function of organelles, thin sections of galactose-treated, KMnO4-fixed bentgrass (Agrostis palustris L.) root apices were examined in the electron microscope. Inhibitory effects were noted on root cap mucilage formation, cell plate formation, cell wall accretion, and the organelles associated with these processes such as the dictyosomes and the endoplasmic reticulum. These studies suggest that D-galactose inhibits root elongation by not only suppressing the synthesis of cell wall precursors—as evidenced by apparent reduction in the activity of the dictyosomes and root cap mucilage formation—but also the cellular processes involved in cell wall accretion and the formation of the cell plate.