The “common” rose literature on PNRSV transmission through rose seeds appears to be based on field observation type experiments in warm climates where the virus may be mainly in the roots and/or on field based experiments that utilized too small a sample size to statistically detect low transmission rates. See my summary at:
http://home.roadrunner.com/~kuska/rose%20virus%20and%20pollen.htm
The following paper illustrates the type of detailed experiment that scientists are now capable of performing that should settle the specific question of PNRSV transfer in roses:
http://jgv.sgmjournals.org/cgi/content/abstract/vir.0.009647-0v1
(Only the abstract is available free to the general public.)
In the full paper their last concluding paragraph is:
" Taking all of our data into account, we suggest that PNRSV is most probably transmitted by apricot seeds through gametes and not indirectly from the testa."
Link: jgv.sgmjournals.org/cgi/content/abstract/vir.0.009647-0v1