Virus and Bacterial Galls

Abstract

Viruses give rise to diverse growth abnormalities in plants, such as leaf curling, leaf crinkling, fasciation, bunching, etiolation, swelling, etc. in addition to various other structural and functional disturbances. Whether any of the growth abnormalities should be included under galls depends partly on the limitations of the customary definitions of galls and partly on the vagueness of our concept of virus. It does not seem to have been satisfactorily decided whether a virus is an organism in the ordinary sense or only a giant proteid molecule.