Looks like tobacco mosaic virus. This infects many plants and usually a MJ plant will outgrow the effects of this virus if the plant isn't too small. The virus can spread easily from plant to plant making your host plant not suitable for cloning.
Tomatoes, squash and several similiar type plants are a prime carrier of this virus. Once this virus is loose within your grow it is very hard to control without isolating infecting plants from others and making sure that you keep tools, hands and anything else that comes into contact with the affective plants clean before touching other plants.
Hope this helps and the best of luck to your grow