Lectins as Cytochemical Probes of the Developing Wheat Grain. IV. Demonstration of Mucilage Containing L-Fucose Associated With Roots in Ungerminated Grain

Abstract

Fluorescein-labelled lectins from Ulex europaeus and Lotus tetragonolobus, each with a specific binding affinity for L-fucose, reacted with carbohydrate material in the root cap and surrounding the roots in the embryos of developing wheat grains. The reactions were completely inhibited by preincubation of the lectins with L-fucose and were observed throughout development of the grain from 6 days post-anthesis to physiological maturity 29 days later. These findings provide the first demonstration of the location of L-fucose in the wheat grain. Although a lectin-reactive slime or mucilage containing L-fucose has been studied by others in the roots of germinated cereal grains, particularly maize, our results demonstrate that such a mucilage already occurs around the roots prior to germination.