Mucilage on the Root Surface and Root Hairs of Sorghum: Heterogeneity in Structure, Manner of Production and Site of Accumulation

Abstract

Small drops of a mucilaginous character near the tip of root hairs were seen by light microscopy in several species of Sorghum and the Sorghum hybrid Vidan. Electron microscopy revealed that the drops are formed from at least two distinct substances, both apparently secreted from the endoplasmic reticulum. In addition, a patchy, fibrillar mucilaginous layer, also with at least two components, was found on the cell wall of the root hairs and on the outer wall of ordinary root epidermal cells. Golgi bodies as well as mitochondria take part in its production. As a rule, the mucilaginous patches are colonized by bacteria.