Lysis of bacterial colony in culture is seen by which -

Bacteriophage: A bacteriophage is a type of virus that infects bacteria. Word "bacteriophage" means "bacteria eater," because bacteriophages destroy their host cells. . Lytic phages can kill the bacteria hence causing lysis in culture medium This propey can also be used in treatment of bacterial infection, such as post-burn and wound infections. (Phage therapy)