Visualization of Tobacco Mosaic Virus Within Infected Cells

Summary

Electron micrographs of sections cut through tobacco leaves infected with tobacco mosaic indicate that the virus is often present in fibrous masses associated with chloroplasts which are severely affected. Virus can clearly be seen in the cytoplasm of the diseased cells sometimes as single filaments. The nuclei seem unaltered by the infective process and have appeared free of virus. The great length of these filaments, much in excess of 2800A, indicates an end-to-end arrangement of the rods in situ.