Similarly, some nematodes, the microscopic roundworms in the soil, may carry viruses to a healthy plant when feeding with their sharp, hollow stylets. Once inside a host cell, the virus removes its protein coat and begins to make numerous copies of itself. Everything a virus needs to copy itself comes from the plant's cell. The first copies can be completed in as little as 10 hours. The copied virus then begins to move to new cells via tiny cellular strands called plasmodesmata, which form a network throughout the plant.
Viruses produce special proteins that help modify the plasmodesmata for easier passage to new cells.
Like something in a science fiction movie, viruses move through these minute passageways from cell to cell. Once viruses reach the living phloem cells, which make up the vascular tissue that transports food, they can spread quite rapidly until the entire plant may be infected. Any part of the plant, including the leaves, tubers, fruits, or even the seeds within the fruits, may contain the insidious virus. The implications for propagation are serious. Any part taken from a virus-infected plant may itself be infected.