The Occurrence of a Previously Unobserved Polysaccharide in Immature Infected Cells of Root Nodules of Trifolium Ambiguum M. Bieb. And Other Members of the Trifolieae

Abstract

A type of ineffective nodulation is described in which the bacteroids in the nodule cells fail to mature, and in which the infected host cells accumulate watersoluble polysaccharide between protoplast and cell wall. Ineffectiveness of this kind is characteristic of nodules· on Trifolium ambiguum M. Bieb. produced by unadapted strains of bacteria, or produced by adapted strains on a small proportion of plants. It is also found when strains effective with T. ambiguum nodulate subterranean or white clover. The polysaccharide in the peripheries of infected cells is readily seen by phase-contrast observation, provided the sections are not hydrated after removal of wax, but it is not visible by ordinary staining procedures.