Infection of tobacco leaf epidermal protoplasts with tobacco mosaic virus.

Protoplasts from the epidermal cells of tobacco leaves were prepared and inoculated with tobacco mosaic virus. Up to 50% of the protoplasts became infected and, within 3 days, contained an average of 5 x 10(5) virus particles per protoplast. Hexagonal crystalline inclusions were observed in many of the infected protoplasts.