An article at Wikipedia describes color changes that viruses have produced in tulips (without any human intention). And another article (elsewhere on the web) describes viruses that were designed to fight diseases in people. This makes me wonder:
Would it be possible to design a virus to produce certain coloration in tulips -- for example, if I want tulips to have white petals with blue streaks? Would this create a new strain of tulips that propagate that coloration without further human interference?