Ultrastructural studies on the bacterium associated with the ratoon stunting disease of sugarcane

Abstract

The bacterium associated with ratoon stunting disease of sugar-cane was studied in thin sections of agar-embedded pellets of fibrovascular extracts, and in situ in the xylem of sugar-cane. The bacterium often possessed a single large lamellar mesosome, and the cell wall was smooth in outline and of the Gram-positive type. It lacked the acidic mucopolysaccharide capsule which was observed in several species of plant pathogenic coryneform bacteria. The bacterium was seen in the lumen and the pits of the xylem vessels and sometimes appeared to be in the xylem cell wall.